| 1. |
- Alfirevic, Ana, et al.
(författare)
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In silico analysis of HLA associations with drug-induced liver injury : use of a HLA-genotyped DNA archive from healthy volunteers
- 2012
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Ingår i: Genome Medicine. - : BioMed Central. - 1756-994X. ; 4:6
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Drug-induced liver injury (DILI) is one of the most common adverse reactions leading to product withdrawal post-marketing. Recently, genome-wide association studies have identified a number of human leukocyte antigen (HLA) alleles associated with DILI; however, the cellular and chemical mechanisms are not fully understood.METHODS: To study these mechanisms, we established an HLA-typed cell archive from 400 healthy volunteers. In addition, we utilized HLA genotype data from more than four million individuals from publicly accessible repositories such as the Allele Frequency Net Database, Major Histocompatibility Complex Database and Immune Epitope Database to study the HLA alleles associated with DILI. We utilized novel in silico strategies to examine HLA haplotype relationships among the alleles associated with DILI by using bioinformatics tools such as NetMHCpan, PyPop, GraphViz, PHYLIP and TreeView.RESULTS: We demonstrated that many of the alleles that have been associated with liver injury induced by structurally diverse drugs (flucloxacillin, co-amoxiclav, ximelagatran, lapatinib, lumiracoxib) reside on common HLA haplotypes, which were present in populations of diverse ethnicity.CONCLUSIONS: Our bioinformatic analysis indicates that there may be a connection between the different HLA alleles associated with DILI caused by therapeutically and structurally different drugs, possibly through peptide binding of one of the HLA alleles that defines the causal haplotype. Further functional work, together with next-generation sequencing techniques, will be needed to define the causal alleles associated with DILI.
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| 2. |
- Assenhöj, Maria, et al.
(författare)
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Protein interaction, monocyte toxicity and immunogenic properties of cerium oxide crystals with 5% or 14% gadolinium, cobalt oxide and iron oxide nanoparticles–an interdisciplinary approach
- 2021
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Ingår i: Nanotoxicology. - : Taylor and Francis Ltd.. - 1743-5390 .- 1743-5404. ; 15:8, s. 1035-1038
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Tidskriftsartikel (refereegranskat)abstract
- Metal oxide nanoparticles are widely used in both consumer products and medical applications, but the knowledge regarding exposure-related health effects is limited. However, it is challenging to investigate nanoparticle interaction processes with biological systems. The overall aim of this project was to improve the possibility to predict exposure-related health effects of metal oxide nanoparticles through interdisciplinary collaboration by combining workflows from the pharmaceutical industry, nanomaterial sciences, and occupational medicine. Specific aims were to investigate nanoparticle-protein interactions and possible adverse immune reactions. Four different metal oxide nanoparticles; CeOx nanocrystals with 5% or 14% Gd, Co3O4, and Fe2O3, were characterized by dynamic light scattering and high-resolution transmission electron microscopy. Nanoparticle-binding proteins were identified and screened for HLA-binding peptides in silico. Monocyte interaction with nanoparticle–protein complexes was assessed in vitro. Herein, for the first time, immunogenic properties of nanoparticle-binding proteins have been characterized. The present study indicates that especially Co3O4-protein complexes can induce both ‘danger signals’, verified by the production of inflammatory cytokines and simultaneously bind autologous proteins, which can be presented as immunogenic epitopes by MHC class II. The clinical relevance of these findings should be further evaluated to investigate the role of metal oxide nanoparticles in the development of autoimmune disease. The general workflow identified experimental difficulties, such as nanoparticle aggregate formation and a lack of protein-free buffers suitable for particle characterization, protein analyses, as well as for cell studies. This confirms the importance of future interdisciplinary collaborations. © 2021 The Author(s).
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| 3. |
- Cederbrant, Karin, et al.
(författare)
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Characterization of mercuric mercury (Hg2+)-induced lymphoblasts from patients with mercury allergy and from healthy subjects
- 2000
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Ingår i: Clinical and Experimental Immunology. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 121:1, s. 23-30
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Tidskriftsartikel (refereegranskat)abstract
- Hg2+ induces lymphocyte proliferation when added to cell cultures from both healthy and mercury-allergic subjects. Consequently, when measuring DNA synthesis a possible Hg2+-specific response, resulting from proliferating memory cells, cannot be discriminated from a non-allergic response. The mechanism behind this non-allergic response is unknown but a superantigenic effect of Hg2+ has been suggested. In this study, five mercury-allergic patients, with oral lichen planus (OLP) lesions adjacent to dental amalgam and a positive patch test to Hg0, and five healthy subjects without amalgam were examined. The immunophenotype and the T cell receptor Vβ (TCR Vβ) repertoire of Hg2+-induced lymphoblasts as well as the expression of the lymphocyte activation markers CD23 and CD134 were analysed for possible differences between healthy and allergic subjects. The mechanism of Hg2+-induced proliferation was examined by comparing the TCR Vβ expression of Hg- and staphylococcal enterotoxin B (SEB)-activated lymphoblasts, the latter used as a positive superantigen control. It was not possible to discriminate between mercury-allergic and healthy subjects using the immunophenotype or the TCR Vβ profile of the Hg2+-induced lymphoblasts or the expression of CD23 and CD134. However, Hg2+-induced CD4+ lymphoblasts showed a skewing towards Vβ2. This relative increase in Vβ2 was only detected in the CD4+ but not in the CD8+ lymphoblast population. In conclusion, Hg2+ induced a proliferation-dependent skewing towards CD4+ but not CD8+ lymphocytes expressing Vβ2. In this respect Hg2+ differs from the classical bacterial superantigen SEB, which also stimulates unique TCR Vβ families among CD8+ cells.
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| 4. |
- Cederbrant, Karin, et al.
(författare)
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Characterization of primary recall in vitro lymphocyte responses to bacampicillin in allergic subjects
- 2000
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Ingår i: Clinical and Experimental Allergy. - : Wiley. - 0954-7894 .- 1365-2222. ; 30:10, s. 1450-1459
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundAntigen-specific cell lines or clones are often used as models of drug-specific allergy. However, cloning procedures are time consuming, and the repeated antigen stimulation cycles as well as the addition of various growth enhancers may affect the in vivo relevance of these systems.ObjectiveUsing bacampicillin-allergic subjects, we wanted to investigate the applicability of primary recall in vitro lymphocyte responses to characterize type I and type IV allergy. The sensitivity and specificity of LTT (Lymphocyte transformation test), when used as an in vitro diagnostic tool, were also assessed.MethodsA total of 39 patients with symptoms of type I (rhinitis) or type IV (allergic contact dermatitis, ACD) allergy following occupational exposure to bacampicillin, were included. Ten individuals without penicillin allergy or occupational exposure to bacampicillin served as controls. All subjects were LTT tested. Four patients with rhinitis and two patients with ACD were available for studying the immunophenotype and the TCR-Vβ repertoire of bacampicillin induced lymphoblasts as well as the cytokine profiles and expression of the activation markers CD23 and CD134 in primary PBMC cultures.ResultsLTT was positive in 87% and at least one of the skin tests was positive in 85% of the patients with allergic symptoms. 69% of the patients with type I allergies were patch test-positive. Results from LTT and skin test correlated in 87% of the cases. The combined sensitivity of LTT and skin tests was 92%. The specificity of LTT was 90% in healthy controls. Bacampicillin induced lymphoblasts were mainly CD4 + in both ACD and rhinitis patients. The TCR-Vβ profiles of the predominant CD4 + lymphoblasts were heterogeneous with individual skewing towards Vβ2, Vβ3, Vβ5.1 and/or Vβ14. An increased expression of IFNγ was detected in bacampicillin treated PBMC cultures from the ACD but not from rhinitis patients. IL-5 was detected in bacampicillin exposed PBMC cultures from all patients but not from healthy controls. This Th2 environment could also be verified by CD23 and CD134 expression.ConclusionLTT and skin tests are equally sensitive in identifying bacampicillin allergic subjects. When the two tests are combined, the sensitivity increases. The patch test is useful not only for detection of type IV but also for the identification of type I allergies. When using primary PBMC cultures, IFNγ is the most suitable cytokine to discriminate between type I and type IV allergy. IL-5 can possibly be used as a general marker for bacampicillin induced allergy. Thus, primary cell cultures may be considered as an alternative to T-cell lines or clones for the study of drug induced allergy.
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| 5. |
- Cederbrant, Karin, et al.
(författare)
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Cytokine production, lymphocyte proliferation and T-cell receptor Vbeta expression in primary peripheral blood mononuclear cell cultures from nickel-allergic individuals
- 2003
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Ingår i: International Archives of Allergy and Immunology. - : S. Karger AG. - 1018-2438 .- 1423-0097. ; 132:4, s. 373-379
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Tidskriftsartikel (refereegranskat)abstract
- Background: Clinical history and patch test constitute the two cornerstones in the diagnosis of nickel (Ni) allergy. Due to technical and interpretative limits of the patch test, the in vitro lymphocyte transformation test (LTT) has been developed for confirming contact allergy, however, most studies show an overlap in lymphocyte proliferation between Ni-allergic and nonallergic subjects using the LTT. The aim of this study was to see if the secretion of cytokines, especially interleukin (IL)-10 and IL-17, or the use of T-cell receptor (TCR) V▀ families in Ni-stimulated primary peripheral blood mononuclear cell (PBMC) cultures might be more useful for discriminating between allergic and nonallergic subjects. Methods: Ni2+-stimulated primary PBMC cultures derived from female subjects diagnosed as Ni-allergic (n = 5) or nonallergic (n = 5) on the basis of a positive or negative patch test were assessed for cell proliferation by tritiated thymidine incorporation and for production of interferon-?, IL-4, IL-10 and IL-17 in the culture supernatant by ELISA. The immunophenotype and TCR-V▀ family affiliation of the Ni2+-induced lymphoblasts were determined by flow cytometry. Results: Lymphocytes from Ni-allergic individuals challenged with a high and a low concentration of Ni showed significantly higher cell proliferation than lymphocytes from nonallergic individuals, but all subjects showed a positive LTT result (stimulation index>2). We found a significantly higher release of IL-10 in Ni2+-treated cultures from Ni-allergic compared with nonallergic subjects that provided better separation between individuals in the two groups than did lymphocyte proliferation. The proliferating lymphoblasts were predominantly CD4+, and in 2 of the 5 Ni-allergic subjects, but in none of the 5 nonallergic subjects, the CD4+ lymphoblasts showed a dominance of TCR-V▀17. Conclusions: Determination of IL-10 production in primary PBMC cultures is a potentially promising in vitro method for discrimination of Ni allergy in females, as compared with cell proliferation. Copyright ⌐ 2003 S. Karger AG, Basel.
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| 6. |
- Cederbrant, Karin, et al.
(författare)
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IL-10 production in primary PBMC cultures : an in vitro marker for nickel allergy?
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Nickel (Ni) is one of the most known contact allergens and at present, patch test and clinical history constitute the two cornerstones in the diagnostic procedure. Since the patch test is inherited with in vivo provocation and subjective interpretation of the test result, a non-invasive in vitro method with objective interpretation of the test result has long been searched for. Unfortunately, in vitro diagnosis of Ni- allergy is hampered by the fact that Ni2+ is able to trigger in vitro proliferative responses in lymphocytes from both Ni-allergic and non-allergic subjects. This constitutes a problem when LTT (lymphocyte transformation test), the most frequently used in vitro test as a complement in the diagnosis of contact allergy, is considered for Ni allergy. However, other parameters in the in vitro response might be more useful. In this study, Ni2+-stimulated primary PBMC-cultures derived from Ni-allergic and non-allergic subjects were assessed for IFN-γ, IL-4, IL-10 and IL-17. Also, Ni2+ induced lymphoblasts from such cultures were characterized by their immunophenotype and T-cell receptor Vß-affiliation.We found a significantly higher release of IL-10 in Ni2+ treated cultures from allergic than from non-allergic subjects. The Ni2+-induced lymphoblasts from both groups were predominantly CD4+. Two of the allergic patients (n=5) showed a skewing towards TCR-Vß17, a Vß family earlier associated with Ni-allergy. A significant increase in CD134 and CD23 expression indicated that Ni2+ activates B-cells in vitro. In conclusion, IL-10 seems to be a promising marker for Ni-allergy using primary PBMC cultures. Further, flow cytometric screening of Ni2+ induced lymphoblasts can detect expanded TCR-Vß families that may be used for preparation of Ni-specific T cell clones.
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| 7. |
- Cederbrant, Karin, et al.
(författare)
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In vitro Lymphocyte Proliferation as Compared to Patch Test Using Gold, Palladium and Nickel
- 1997
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Ingår i: International Archives of Allergy and Immunology. - : S. Karger AG. - 1018-2438 .- 1423-0097. ; 112:3, s. 212-217
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Tidskriftsartikel (refereegranskat)abstract
- Background: A conventional lymphocyte transformation test (LTT) was compared to the commercially available MELISA® (memory lymphocyte immuno-stimulation assay), a lymphoproliferative assay that has been suggested to be a valuable instrument for the diagnosis of metal allergy. Sensitivity and specificity of the two assays were calculated using a patch test as a reference method.Methods: 34 patients were patch-tested for gold sodium thiosulfate, palladium chloride and nickel sulfate, and the lymphocyte proliferation to these metals was tested in vitro using mononuclear cells from peripheral blood.Results: No significant differences regarding sensitivity and specificity were found between MELISA and conventional LTT. The sensitivity varied between 55 and 95% and the specificity between 17 and 79%.Conclusions: The low specificity of the two in vitro assays suggests that they are not useful for diagnosis of contact allergy to the metals gold, palladium and nickel, since a large number of false-positive results will be obtained.
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| 8. |
- Cederbrant, Karin, et al.
(författare)
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In vitro Lymphoproliferative Assays with HgCl2 Cannot Identify Patients with Systemic Symptoms Attributed to Dental Amalgam
- 1999
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Ingår i: Journal of Dental Research. - : SAGE Publications. - 0022-0345 .- 1544-0591. ; 78:8, s. 1450-1458
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Tidskriftsartikel (refereegranskat)abstract
- Dental amalgam is suspected, by some exposed individuals, to cause various systemic psychological, sensory, and neurological symptoms. Since not all amalgam-bearers experience such reactions, an individual characteristic—for example, a susceptible immune system—might explain these conditions. In vitro lymphocyte proliferation is a valuable tool in the diagnosis of allergy. With HgCl2 as the antigen, however, the test is hampered, because Hg2+ can cause unspecific lymphocyte proliferation, optimal at 1.4 to 9.5 μg HgCl2/mL. Recently, the use of suboptimal HgCl2 concentrations (≤ 0.5 μg/mL) has been suggested to circumvent these problems. The main aim of this study was to investigate whether patients with systemic symptoms alleged to result from the presence of dental amalgam differ from healthy controls, with reference to in vitro lymphoproliferative responses to HgCl2 ≤ 0.5 μg/mL. Three different test protocols—lymphocyte transformation test (LTT) in micro- and macro-cultures, and the memory lymphocyte immunostimulation assay (MELISA®)—were used. Other immune parameters—such as a standard patch test for dental materials, the number of T- and B-lymphocytes, monocytes, granulocytes, and NK cells in peripheral blood, allergic symptoms, and predisposition-were also investigated. Twenty-three amalgam patients, 30 healthy blood donors with amalgam, ten healthy subjects without amalgam, and nine patients with oral lichen planus (OLP) adjacent to dental amalgam and a positive patch test to Hg0 were tested. None of the investigated immune parameters revealed any significant differences between amalgam patients and controls. The sensitivity of in vitro lymphocyte proliferation ranged from 33 to 67%, with the OLP patients as a positive control group, and the specificity from 0 to 70% for healthy controls with a negative patch test to Hg°. Thus, despite the use of HgCl2 ≤ 0.5 μg/mL, a high frequency of positive results was obtained among healthy subjects with or without dental amalgam. Consequently, in vitro lymphocyte proliferation with HgCl2 cannot be used as an objective marker for mercury allergy in dental amalgam-bearers.
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| 9. |
- Cederbrant, Karin, 1964-
(författare)
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The Primary Lymphocyte Culture in the Diagnosis of Drug- and Metal-Induced Allergy
- 2000
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Drugs and metals are examples of xenobiotics that can induce hypersensitivity in humans. These adverse reactions are classified as allergy if repeated exposure leads to the same type of clinical manifestation. Together with the clinical history, the skin test is the most commonly used test for the diagnosis of allergic disease. However, in vivo testing per se has drawbacks such as the risk of potentiation of the allergy or even sensitisation to a given test substance. For this reason in vitro testing is an attractive diagnostic alternative since it does not involve any exposure of the test subject to the allergen.The lymphocyte transformation test (LTT) has been used to complement the diagnosis of allergy to drugs and metals for more than thirty years. The principle behind this test is to show the presence of allergen-specific memory lymphocytes in peripheral blood, which is a sine qua non of a true allergy. LTT reveals the proliferation of such cells by showing DNA synthesis as the uptake of 3H-thymidine in primary PBMC (peripheral blood mononuclear cell) cultures treated with the allergen. However, LIT has not yet been generally accepted as a stand-alone test in the diagnosis of allergy. One reason for this is that different chemical properties of the allergens may lead to either false positive or false negative LTT responses.In the present study we investigated allergy to the drug bacampicillin and to the metals Au, Pd, Ni and Hg. Three different protocols for LTT: LIT in micro cultures (LTT-micro), LTT in macro cultures (LTT-macro) and memory lymphocyte immunostimulation assay (MELISA) were compared using a skin test or clinical history as reference methods. LTI showed a sensitivity of 87% and a specificity of 90% when used in the diagnosis of allergy to bacampicillin. When allergy to Au, Pd, Ni and Hg was investigated, the sensitivity was 33- 95% and the specificity 0-79%. There were no significant differences between the test protocols, except that MELISA showed a significantly higher specificity than LTT-micro and LTT-macro when Hg2+ was used as antigen. Even so, this specificity was only 70%, which would result in 30 of 100 healthy subjects receiving a false diagnosis of Hg allergy when using the MELISA protocol. Ni2+ also induced high numbers of false-positive LTI responses, 77-85% patch-test negative subjects showed positive results to these metals. However, group comparisons showed a significantly higher proliferation intensity in allergic than in nonallergic groups for all allergens except Hg2+. Furthermore, only 56% of patients with verified allergy to mercury showed a positive MELISA, a sensitivity that is unacceptably low.Following these findings, we investigated whether other endpoints than DNA synthesis could be used to discriminate allergic from healthy subjects, using primary PBMC cultures with Hg2+ or Ni2+ as a model system. Analysis of the T-cell receptor Vß profiles of lymphoblasts induced by these metal ions showed individual patterns, and there was no difference between healthy and allergic groups. However, the fraction of CD4+/Vß2+ cells correlated significantly with the proliferation intensity induced by Hg2+ in patients with a verified Hg allergy but not in non-allergic controls. Interestingly, such a correlation was not seen with CD8+/Nß2+ cells. This indicates that Hg2+ does not function as a superantigen, since classical superantigens also stimulate CD8+ lymphocytes. When Ni2+ was used as antigen we found significantly higher IL-10 production in allergic than in non-allergic subjects, despite no significant difference in proliferation intensity between these two groups.In conclusion, the LTT test is useful for the diagnosis of allergy to bacampicillin. Regarding Au, Pd and Ni the LIT has low validity and can only be used to discriminate groups of allergic from non-allergic individuals. LTT with Hg2+ and Ni2+ is not useful for the diagnosis of allergy to these metals since a high fraction of non-allergic individuals show positive results, irrespective of the test protocol used. This thesis calls for further studies on the usefulness of in vitro IL-10 production for the diagnosis of Ni allergy as well as on the specificity of in vitro induced CD4+N~2+ lymphoblasts from Hg allergic subjects.
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| 10. |
- Christiansen Clifford, Jenny, et al.
(författare)
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Interferon-gamma secreted from peripheral blood mononuclear cells as a possible diagnostic marker for allergic contact dermatitis to gold
- 2006
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Ingår i: Contact Dermatitis. - : Wiley. - 0105-1873 .- 1600-0536. ; 55:2, s. 101-112
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Tidskriftsartikel (refereegranskat)abstract
- 10% of patch-tested patients have a positive reaction to gold. Most lack clinical symptoms, but allergic contact dermatitis (ACD) to gold is increasing. In this study, 77 dermatological outpatients were divided into 3 groups depending on epicutaneous patch test outcomes: a group positive to gold (EPI+), a group negative to gold (EPI-), and a group with irritant reactions to gold (EPI-IR). Lymphocytes were stimulated in vitro with gold sodium thiosulfate. Proliferation was assessed using the lymphocyte transformation test (LTT), and cytokine secretion was assessed using a multibead array (Luminex; Linco Research Inc., St. Charles, MO, USA), in order to evaluate whether an in vitro method with high diagnostic accuracy could be devised. The EPI+ group showed a significantly increased secretion of interferon (IFN)-gamma, interleukin (IL)-2, and IL-13 and also showed a significantly higher stimulation indexes for LTT, compared to the other 2 subject groups. Sensitivity and specificity were calculated for all methods individually and combined, but IFN-gamma assessment alone was the most accurate method for identifying ACD to gold, with sensitivity and specificity of 81.8% and 82.1%, respectively. This method also identified 87.5% of the EPI-IR subjects as non-allergic. Therefore, assessment of secretion of IFN-gamma should be a valuable complement to patch test for diagnosing gold allergy.
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| 11. |
- Clifford, Jenny, 1980-
(författare)
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Gold allergy : In vitro studies using peripheralblood mononuclear cells
- 2009
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Positive patch test reactions to gold are commonly seen in dermatology clinics, but it is veryunusual for the patients to actually have any clinical symptoms. It is also common with irritantreactions that are not linked to adaptive immunity. Therefore, a deeper understanding of themechanisms underlying allergic contact dermatitis (ACD) reaction, and the search for acomplementing diagnostic tool, is important.In paper I we included three subject groups; one with morphologically positive patch testreactions to gold sodium thiosulphate (GSTS, the gold salt used in patch testing), one withnegative patch tests, and one with irritant reactions to gold. Blood samples were collected andexamined regarding the proliferation rate and which cytokines were secreted after culturingwith GSTS. We saw that the cultured lymphocytes from the allergic donors proliferated at asignificantly higher rate than the two other subject groups, and that the cells secreted cytokinesof both Th1 (Interferon (IFN) -g and Interleukin (IL) -2) and Th2 (IL-13 and IL-10) types. Theallergic donors secreted significantly higher levels of IFN-g, IL-2 and IL-13 than the two othersubject groups. Both the negative and irritant subject groups showed suppressed levels of thecytokines as compared with the unstimulated cultures, demonstrating the immunosuppressingeffects of gold.We also examined whether any of the analyzed markers, alone or combined, could be usedas an aid for diagnosing ACD to gold. We found that the IFN-g assay yielded the highestsensitivity (81.8 %) and specificity (82.1 %), and also identified 87.5 % of the irritant group asnon-allergic.In paper II we decided to investigate what cell types and subsets that reacted to the goldstimulation. We analyzed proliferation rate and expression of CD45RA, CD45R0, cutaneouslymphocyte-associated antigen (CLA) and the chemokine receptors CXCR3, CCR4 andCCR10. Similar to what has previously been published about nickel (Ni) allergy, the cells fromthe gold-allergic subjects that reacted to the GSTS stimulation expressedCD3+CD4+CD45R0+CLA+. However, contrary to findings in studies on Ni-reactive cells, wesaw no differences between allergic and non-allergic subjects regarding any of the chemokine receptors studied.In conclusion, we found that analysis of IFN-g might be a useful complement to patchtesting, possibly of interest in avoiding the need for repeated tests to rule out irritant reactions.We also saw that the cells that proliferated in response to gold were memory T-cells expressingCD4 and CLA, the marker for skin-homing. However, these cells did not express elevatedlevels of any of the chemokine receptors analyzed, showing that there are both similarities anddifferences between the mechanisms for Ni allergy and gold allergy.
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| 12. |
- Clifford, Jenny, 1980-, et al.
(författare)
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T-cells expressing CD4, CD45RO and CLA from gold-allergic but not healthy subjects react to gold sodium thiosufate in vitro
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Patch test positivity to gold is common in western societies, but in contrast to nickel (Ni) allergy it is uncommon that the patch test positive patient shows any clinical symptoms. In this study we investigated cytotoxic effects of gold sodium thiosulphate (GSTS) on peripheral blood mononuclear cells (PBMC), including different T-cell subsets. We also separated lymphocytes from allergic and non-allergic subjects into CD45RA and CD45R0 cell fractions. We also expressed CLA. The fraction of analyzed the effects of GSTS using lymphocyte transformation test, propidium iodide staining and flow cytometry to determine lymphocyte memory status, expression of chemokine receptors and cutaneous lymphocyte-associated antigen (CLA), and compared the results to what has previously been reported on Ni allergy. We found that only the cells from the allergic subjects proliferated in the lymphocyte transformation test (LTT), and in the CD45R0 fraction there was a dose-dependent increase in the fraction of CD3/CD4 cells. Similar to Ni-allergy, these CD3/CD4/CD45R0 cells also expressed CLA. The fraction of CD3/CD8 in the CD45R0 enriched fraction decreased with GSTS exposure. In contrast to Ni allergy, however, we found no differences between the allergic and non-allergic subjects regarding the chemokine receptors CCR4, CXCR3 and CCR10.
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| 13. |
- Cotgreave, Ian, et al.
(författare)
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Pyriproxifen and microcephaly: an investigation of potential ties to the ongoing "Zika epidemic"
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- As part of the Swetox mission to react to emerging concerns in chemical health and environmental safety, a preliminary litterature investigation was undertaken to gather all readily available scientific information on PPF with respect to safety assessment, in order to better understand potential links between chemical exposure and the devopment of microcephaly in affected areas. Therefore the contents of the report do not constitute an attempt at either questioning the use of existing regulatory data in the manner prescribed by international regulatory proceedures, or as a new risk assessment, based on the scientific information and concepts discussed. Here we report our findings, with particular emphasis on exisiting regulatory information, potential for lack of translation of results from regulatory animal testing to humans, lack of human exposure data and suggestions on plausible mode(s) of action of PPF in human neurodevelopmental adversities such as microcephaly.
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| 14. |
- Faulkner, Lee, et al.
(författare)
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The development of in vitro culture methods to characterize primary T-cell responses to drugs.
- 2012
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Ingår i: Toxicological Sciences. - : Oxford University Press. - 1096-6080 .- 1096-0929. ; 127:1, s. 150-8
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Tidskriftsartikel (refereegranskat)abstract
- Adverse drug reactions represent a major stumbling block to drug development and those with an immune etiology are the most difficult to predict. We have developed an in vitro T-cell priming culture method using peripheral blood from healthy volunteers to assess the allergenic potential of drugs. The drug metabolite nitroso sulfamethoxazole (SMX-NO) was used as a model drug allergen to establish optimum assay conditions. Naive T cells were cocultured with monocyte-derived dendritic cells at a ratio of 25:1 in the presence of the drug for a period of 8 days, to expand the number of drug-responsive T cells. The T cells were then incubated with fresh dendritic cells, and drug and their antigen responsiveness analyzed using readouts for proliferation, cytokine secretion, and cell phenotype. All five volunteers showed dose-dependent proliferation as measured by 5-(and 6)-carboxyfluorescein diacetate succinimidyl ester content and by (3)H-thymidine uptake. CD4 T cells that had divided in the presence of SMX-NO had changed from a naive phenotype (CD45RA+) to a memory phenotype (CD45RO+). These memory T cells expressed the chemokine receptors CCR2, CCR4, and CXCR3 suggesting a mixture of T(H)1 and T(H)2 cells in the responding population, with a propensity for homing to the skin. Drug stimulation was also associated with the secretion of a mixture of T(H)1 cytokines (interferon γ) and T(H)2 cytokines (interleukin [IL]-5 and IL-13) as detected by ELISpot. We are currently developing this approach to investigate the allergenic potential of other drugs, including those where an association between specific human leucocyte antigen alleles and susceptibility to an immunological reaction has been established.
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| 15. |
- Granath, Britta, 1982, et al.
(författare)
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A comparison of the humoral immune response induced by a recombinant human protein in wild type mice and in transgenic mice expressing the protein
- 2014
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Ingår i: British Journal of Pharmaceutical Research. - 2231-2919. ; 4:21, s. 2511-2524
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Tidskriftsartikel (refereegranskat)abstract
- Aim: The aim of this work was to investigate the correlation between anti drug antibody (ADA) induction and how different manufacturing processes of biopharmaceuticals affect the immunogenicity of the protein. This was done by testing four different batches of the same recombinant human protein in transgenic (Tg) mice. Methodology: Wild type (Wt) and human protein-transgenic (Tg) mice were challenged by repeated subcutaneous injections of four batches of a drug candidate protein, obtained by different purification methods. Differences between drug-specific IgG1, IgG2a, IgG2b, IgG3 and IgM antibody patterns produced in Tg vs. Wt mice were investigated and compared to the plasma cytokine profiles. A conventional ELISA was used as a reference method for ADA detection. Results: ADA responses detected in Tg mice were mainly of the IgG1 subclass and occurred only in significant response to the batch containing the highest level of proteins originating from the recombinant host cells. Wt mice, on the other hand, showed a combined IgG1/IgG2b response to all drug batches, except to the batch with the highest purity. The most pure batch failed to induce significant ADA in both Wt and Tg animals, suggesting host cell derived impurities to be a strong contributing factor to the antibody responses observed. Conclusion: Thus, an isolated IgG1 response in drug-tolerant Tg mice may serve as a potential biomarker of an immunological reaction to process-related impurities of the protein drug. In contrast, a combined IgG1/IgG2b-profile, as observed in immunoreactive Wt mice, more likely reflects a xeno-response.
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| 16. |
- Halamoda-Kenzaoui, Blanka, et al.
(författare)
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Bridging communities in the field of nanomedicine
- 2019
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Ingår i: Regulatory toxicology and pharmacology. - : Elsevier BV. - 0273-2300 .- 1096-0295. ; 106, s. 187-196
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Tidskriftsartikel (refereegranskat)abstract
- An early dialogue between nanomedicine developers and regulatory authorities are of utmost importance to anticipate quality and safety requirements for these innovative health products. In order to stimulate interactions between the various communities involved in a translation of nanomedicines to clinical applications, the European Commission's Joint Research Centre hosted a workshop titled "Bridging communities in the field of Nanomedicine" in Ispra/Italy on the 27th -28th September 2017. Experts from regulatory bodies, research institutions and industry came together to discuss the next generation of nanomedicines and their needs to obtain regulatory approval. The workshop participants came up with recommendations highlighting methodological gaps that should be addressed in ongoing projects addressing the regulatory science of nanomedicines. In addition, individual opinions of experts relevant to progress of the regulatory science in the field of nanomedicine were summarised in the format of a survey.
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| 17. |
- Hande, Liv Nesse, et al.
(författare)
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Effect of N-3 Polyunsaturated Fatty Acids on Lipid Composition in Familial Hypercholesterolemia : A Randomized Crossover Trial
- 2022
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Ingår i: Biomedicines. - : MDPI. - 2227-9059. ; 10:8
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Tidskriftsartikel (refereegranskat)abstract
- Individuals with familial hypercholesterolemia (FH) have an increased risk of cardiovascular disease. Treatment is mainly low-density lipoprotein cholesterol (LDL-C) reduction. How omega-3 polyunsaturated fatty acids (n-3 PUFAs) supplements affect lipoproteins in FH subjects is unknown. We hypothesized that a high-dose n-3 PUFA supplement would reduce atherogenic lipoproteins and influence the high-density lipoprotein cholesterol (HDL-C) function. We performed a randomized, double-blinded crossover study with 34 genetically verified FH individuals (18-75 years, clinically stable, statin treatment > 12 months). Treatment was 4 g n-3 PUFAs (1840 mg eicosapentaenoic acid and 1520 mg docosahexaenoic acid daily) or four capsules of olive oil for three months in a crossover design with a washout period of three months. The defined outcomes were changes in triglycerides, lipoproteins, lipoprotein subfractions, apolipoproteins, and HDL-C function. After treatment with n-3 PUFAs, total cholesterol, LDL-C, and triglycerides were reduced compared to placebo (p <= 0.01 for all). Total HDL-C levels were unchanged, but the subfraction of large HDL-C was higher (p <= 0.0001) after n-3 PUFAs than after placebo, and intermediate HDL-C and small HDL-C were reduced after n-3 PUFAs compared to placebo (p = 0.02 and p <= 0.001, respectively). No changes were found in apolipoproteins and HDL-C function. N-3 PUFAs supplements reduced atherogenic lipoproteins in FH subjects, leaving HDL-C function unaffected.
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| 18. |
- Karsten, Stella, et al.
(författare)
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MTH1 as a target to alleviate T cell driven diseases by selective suppression of activated T cells
- 2021
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Ingår i: Cell Death & Differentiation. - Stockholm : Karolinska Institutet, Dept of Oncology-Pathology. - 1350-9047 .- 1476-5403.
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Tidskriftsartikel (refereegranskat)abstract
- T cell-driven diseases account for considerable morbidity and disability globally and there is an urgent need for new targeted therapies. Both cancer cells and activated T cells have an altered redox balance, and up-regulate the DNA repair protein MTH1 that sanitizes the oxidized nucleotide pool to avoid DNA damage and cell death. Herein we suggest that the up-regulation of MTH1 in activated T cells correlates with their redox status, but occurs before the ROS levels increase, challenging the established conception of MTH1 increasing as a direct response to an increased ROS status. We also propose a heterogeneity in MTH1 levels among activated T cells, where a smaller subset of activated T cells does not upregulate MTH1 despite activation and proliferation. The study suggests that the vast majority of activated T cells have high MTH1 levels and are sensitive to the MTH1 inhibitor TH1579 (Karonudib) via induction of DNA damage and cell cycle arrest. TH1579 further drives the surviving cells to the MTH1[superscript low] phenotype with altered redox status. TH1579 does not affect resting T cells, as opposed to the established immunosuppressor Azathioprine, and no sensitivity among other major immune cell types regarding their function can be observed. Finally, we demonstrate a therapeutic effect in a murine model of experimental autoimmune encephalomyelitis. In conclusion, we show proof of concept of the existence of MTH1[superscript high] and MTH1[superscript low] activated T cells, and that MTH1 inhibition by TH1579 selectively suppresses pro-inflammatory activated T cells. Thus, MTH1 inhibition by TH1579 may serve as a novel treatment option against autoreactive T cells in autoimmune diseases, such as multiple sclerosis.
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| 19. |
- Kjellmo, Christian Abendstein, et al.
(författare)
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Bariatric surgery improves lipoprotein profile in morbidly obese patients by reducing LDL cholesterol, apoB, and SAA/PON1 ratio, increasing HDL cholesterol, but has no effect on cholesterol efflux capacity
- 2018
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Ingår i: Journal of Clinical Lipidology. - : ELSEVIER SCIENCE INC. - 1933-2874 .- 1876-4789. ; 12:1, s. 193-202
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Bariatric surgery has been shown to reduce cardiovascular events and cause specific mortality for coronary artery disease in obese patients. Lipoprotein biomarkers relating to low-density lipoprotein (LDL), high-density lipoprotein (HDL), their subfractions, and macrophage cholesterol efflux have all been hypothesized to be of value in cardiovascular risk assessment. OBJECTIVES: The objective of this study was to examine the effect of a lifestyle intervention followed by bariatric surgery on the lipid profile of morbidly obese patients. METHODS: Thirty-four morbidly obese patients were evaluated before and after lifestyle changes and then 1 year after bariatric surgery. They were compared with 17 lean subjects. Several lipoprotein metrics, serum amyloid A (SAA), serum paraoxonase-1 (PON1), and macrophage cholesterol efflux capacity (CEC) were assessed. RESULTS: Average weight loss after the lifestyle intervention was 10.5% and 1 year after bariatric surgery was 33.9%. The lifestyle intervention significantly decreased triglycerides (TGs; 28.7 mg/dL, P amp;lt; .05), LDL cholesterol (LDL-C; 32.3 mg/dL, P amp;lt; .0001), and apolipoprotein B (apoB; 62.9 mu g/mL, P amp;lt; .001). Bariatric surgery further reduced TGs (-36.7 mg/dL, P amp;lt; .05), increased HDL cholesterol (+12 mg/dL, P amp;lt; .0001), and reductions in LDL-C and apoB were sustained. Bariatric surgery reduced large, buoyant LDL (P amp;lt; .0001), but had no effect on the small, dense LDL.The large HDL subfractions increased (P amp;lt; .0001), but there was no effect on the smaller HDL sub fractions. The ratio for SAA/PON1 was reduced after the lifestyle intervention (P amp;lt; .01) and further reduced after bariatric surgery (P amp;lt; .0001). Neither the lifestyle intervention nor bariatric surgery had any effect on CEC. CONCLUSIONS: Lifestyle intervention followed by bariatric surgery in 34 morbidly obese patients showed favorable effects on TGs, LDL-C, and apoB. HDL cholesterol and apoA1 was increased, apoB/apoA1 ratio as well as SAA/PON1 ratio reduced, but bariatric surgery did not influence CEC. (C) 2017 National Lipid Association. All rights reserved.
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| 20. |
- Lappegård, Knut Tore, et al.
(författare)
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Lipoprotein apheresis affects lipoprotein particle subclasses more efficiently compared to the PCSK9 inhibitor evolocumab, a pilot study.
- 2018
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Ingår i: Transfusion and apheresis science. - : Elsevier BV. - 1473-0502 .- 1878-1683. ; 57:1, s. 91-96
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Tidskriftsartikel (refereegranskat)abstract
- Lipoprotein apheresis and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are last therapeutic resorts in patients with familial hypercholesterolemia (FH). We explored changes in lipoprotein subclasses and high-density lipoprotein (HDL) function when changing treatment from lipoprotein apheresis to PCSK9 inhibition. We measured the levels of low-density lipoprotein (LDL) and HDL particle subclasses, serum amyloid A1 (SAA1), paraoxonase-1 (PON1) activity and cholesterol efflux capacity (CEC) in three heterozygous FH patients. Concentrations of all LDL particle subclasses were reduced during apheresis (large 68.0 ± 17.5 to 16.3 ± 2.1 mg/dL, (p = 0.03), intermediate 38.3 ± 0.6 to 5.0 ± 3.5 mg/dL (p = 0.004) and small 5.0 ± 2.6 to 0.2 ± 0.1 mg/dL (p = 0.08)). There were non-significant reductions in the LDL subclasses during evolocumab treatment. There were non-significant reductions in subclasses of HDL particles during apheresis, and no changes during evolocumab treatment. CEC was unchanged throughout the study, while the SAA1/PON1 ratio was unchanged during apheresis but decreased during evolocumab treatment. In conclusion, there were significant reductions in large and intermediate size LDL particles during apheresis, and a non-significant reduction in small LDL particles. There were only non-significant reductions in the LDL subclasses during evolocumab treatment.
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| 21. |
- Lundgren, Hanna, et al.
(författare)
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HLA-DR7 and HLA-DQ2 : Transgenic mouse strains tested as a model system for ximelagatran hepatotoxicity
- 2017
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Ingår i: PLOS ONE. - San Francisco, United States : Public Library of Science. - 1932-6203. ; 12:9
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Tidskriftsartikel (refereegranskat)abstract
- The oral thrombin inhibitor ximelagatran was withdrawn in the late clinical trial phase because it adversely affected the liver. In approximately 8% of treated patients, drug-induced liver injury (DILI) was expressed as transient alanine transaminase (ALT) elevations. No evidence of DILI had been revealed in the pre-clinical in vivo studies. A whole genome scan study performed on the clinical study material identified a strong genetic association between the major histocompatibility complex alleles for human leucocyte antigens (HLA) (HLA-DR7 and HLA-DQ2) and elevated ALT levels in treated patients. An immunemediated pathogenesis was suggested. Here, we evaluated whether HLA transgenic mice models could be used to investigate whether the expression of relevant HLA molecules was enough to reproduce the DILI effects in humans. In silico modelling performed in this study revealed association of both ximelagatran (pro-drug) and melagatran (active drug) to the antigen-presenting groove of the homology modelled HLA-DR7 molecule suggesting "altered repertoire" as a key initiating event driving development of DILI in humans. Transgenic mouse strains (tgms) expressing HLA of serotype HLA-DR7 (HLA-DRB1*0701, -DRA*0102), and HLA-DQ2 (HLA-DQB1*0202, -DQA1*0201) were created. These two lines were crossed with a human (h) CD4 transgenic line, generating the two tgms DR7xhCD4 and DQ2xhCD4. To investigate whether the DILI effects observed in humans could be reproduced in tgms, the mice were treated for 28 days with ximelagatran. Results revealed no signs of DILI when biomarkers for liver toxicity were measured and histopathology was evaluated. In the ximelagatran case, presence of relevant HLA-expression in a preclinical model did not fulfil the prerequisite for reproducing DILI observed in patients. Nonetheless, for the first time an HLA-transgenic mouse model has been investigated for use in HLA-associated DILI induced by a low molecular weight compound. This study shows that mimicking of genetic susceptibility, expressed as DILI-associated HLA-types in mice, is not sufficient for reproducing the complex pathogenesis leading to DILI in man.
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| 22. |
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| 23. |
- Martinsson, Klara, et al.
(författare)
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Cytokines in induction of ANoA and hypergammaglobulinemia in mercury-induced autoimmunity : a lesson from Fc!RIII deficient mice
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Xenobiotic agents such as metals, drugs, toxic oils and pristane can induce autoimmune diseases. Heavy metal induction of autoimmunity has been observed for mercury (Hg), silver and gold in mice. Mercury-induced autoimmunity (HgIA) in mice is characterised by lymphoproliferation, hypergammaglobulinemia, antinucleolar autoantibodies (ANoA) and immune complex deposits in the renal glomerular mesangium and systemically in vessel walls. HgIA is T-cell dependent, IFNγ is necessary for all manifestations of HgIA, and the activating Fc!RIII enhance development of ANoA. This study focused firstly on exploring the cytokine profile in the genetically susceptible DBA/1 (H-2q) wild type (wt) and DBA/1 FcγRIII-/- mice treated with 15 mg/l Hg, and secondly on the hypothesis that IFN-! producing NK cells are vital for induction of ANoA in the HgIA model. DBA/1 wt mice showed a significantly more marked Th1 profile compared to DBA/1 FcγRIII-/- mice following Hg treatment, whereas the total Th2 and Th17 profile increased in both DBA/1 wt and DBA/1 FcγRIII-/- mice. However, during Hg treatment IL-21 mRNA expression was significantly reduced in DBA/1 FcγRIII-/- mice compared with DBA/1 wt mice. However, we were unable to show that the increased Th1 profile in the DBA/1 wt mice was due to IFN-γsecretion from NK cells. Our findings suggest that the delayed ANoA induction in DBA/1 FcγRIII-/- mice is due to the attenuated Th1 profile. In addition the reduced expression of IL-21 in DBA/1 FcγRIII-/- mice might be responsible for the lack of serum IgG1 response in these mice.
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| 24. |
- Martinsson, Klara, 1977-
(författare)
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Fcγ-receptors in systemic autoimmune conditions : lessons from murine mercury-induced autoimmunity
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis we investigated the role of activating (FcγRI, FcγRIII) and inhibitory (FcγRIIB) Fcγ-receptors on systemic autoimmunity using two mouse strains, DBA/1 (H-2q) and BALB/c mice (H-2d), susceptible to induction of autoimmunity by mercury (Hg).Fc-receptors for IgG (FcγR) link cellular and humoral immune responses, control the balance between activating and inhibitory immune responses and are important in the development of several autoimmune diseases. Mercury induces a T cell-dependent autoimmune condition, Hg-induced autoimmunity (HgIA) in genetically (H-2s,q,f,t2) susceptible mice characterized in its fullblown type by lymphoproliferation, hypergammaglobulinemia, systemic immune-complex (IC) deposits and antinucleolar antibodies (ANoA). All manifestations in HgIA are dependent on the presence of IFN-γ.Hg-treated BALB/c mice lacking activating FcγRs (FcγRI, FcγIII and FcεRI) showed significantly higher levels of both IgG1- and IgG2a-CIC whereas renal mesangial and vessel wall IC deposits were severely delayed and reduced/abolished, compared to mice without mutations (wild type, wt). Wt mice developed modest levels of IgG1- and IgG2a-CIC followed by a distinct formation of IC deposits in the renal glomerular mesangium, as well in renal and splenic vessel walls. Compared to wt mice, the mice lacking the inhibitory FcγRIIB showed similar titres of IC deposits in the renal mesangium, whereas vessel wall IC deposits were reduced.DBA/1 mice deficient for the FcRγ-chain (lack of the activating receptors FcγRI, FcγIII and FcεRI) or FcγRIII and treated with Hg showed a delayed and attenuated IgG1, IgG2a and IgG2b ANoA response compared to wt mice.Increasing the Hg dose or prolonging the treatment time could not override the attenuated ANoA response seen in FcγRIII mice. Female Hg-treated FcγRIIB mice showed a significant increase of IgG2b ANoA development compared to wt mice.The total serum IgG1 response due to treatment with Hg was attenuated in both BALB/c mice lacking the Fcγ-chain, and in DBA/1 mice lacking either the Fcγ- chain or specifically the FcγRIII compared to wt mice. This indicates that FcγRIII is the receptor important for the in HgIA characteristic serum IgG1 response. On the other hand, Hg-treated FcγRIIB deficient BALB/c and DBA/1 mice showed an increase of both serum IgG1 and IgE compared to wt mice.The cytokine profile in DBA/1 wt mice treated with Hg revealed a more marked Th1 profile compared to FcγRIII deficient mice. In contrast, the total Th2 and Th17 profile increased in both wt and FcγRIII deficient mice. However, during Hg treatment IL-21 mRNA expression was significantly reduced in FcγRIII deficient mice compared with wt mice. The increased Th1 profile in the wt mice could not be attributed to an increase of IFN-γ secretion from the major IFN-γ cell source, NK cells.We conclude that FcγRIII are important for the formation of IC deposits as shown by the delayed and reduced formation of IC deposits and the high levels of CIC in mice lacking FcγRIII. The expression of FcγRIII is also of importance for the rapidity and final strength of the ANoA response probably due to a reduced expression of Th1 cytokines and inflammatory factors. The ANoA response is modestly counter-regulated by FcγRIIB. The increase of serum IgG1 in HgIA is dependent on FcγRIII which is likely to be mediated by the low expression of IL- 21 in mice deficient for FcγRIII. In contrast, lack of FcγRIIB increases both the serum IgG1 and IgE response.
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| 25. |
- Åkerlund, Thomas, et al.
(författare)
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Stable IgG-antibody levels in patients with mild SARS-CoV-2 infection
- 2021
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Ingår i: Medrxiv. - : Cold Spring Harbor Laboratory.
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Tidskriftsartikel (refereegranskat)abstract
- More knowledge regarding persistence of antibody response to SARS-CoV-2 infections in the general population with mild symptoms is needed. We measured and compared levels of SARS CoV-2 spike- and nucleocapsid-specific IgG-antibodies in serum samples from 145 laboratory confirmed COVID-19 cases and 324 non-cases. The IgG-antibody levels against the spike protein in cases were stable over the time-period studied (14 to 256 days), while antibody levels against the nucleocapsid protein decreased over time
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