| 1. |
- Aljadi, Zenib, et al.
(författare)
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A novel tool for clinical diagnosis of allergy operating a microfluidic immunoaffinity basophil activation test technique
- 2019
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Ingår i: Clinical Immunology. - : ACADEMIC PRESS INC ELSEVIER SCIENCE. - 1521-6616 .- 1521-7035. ; 209
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Tidskriftsartikel (refereegranskat)abstract
- The Basophil Activation Test (BAT) is a valuable allergy diagnostic tool but is time-consuming and requires skilled personnel and cumbersome processing, which has limited its clinical use. We therefore investigated if a microfluidic immunoaffinity BAT (miBAT) technique can be a reliable diagnostic method. Blood was collected from allergic patients and healthy controls. Basophils were challenged with negative control, positive control (anti-FccRI), and two concentrations of a relevant and non-relevant allergen. CD203c and CD63 expression was detected by fluorescent microscopy and flow cytometry. In basophils from allergic patients the CD63% was significantly higher after allergen activation as compared to the negative control (p < .0001-p = .0004). Activation with non-relevant allergen showed equivalent CD63% expression as the negative control. Further, the miBAT data were comparable to flow cytometry. Our results demonstrate the capacity of the miBAT technology to measure different degrees of basophil allergen activation by quantifying the CD63% expression on captured basophils.
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| 2. |
- Aljadi, Zenib, et al.
(författare)
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Activation of Basophils Is a New and Sensitive Marker of Biocompatibility in Hemodialysis
- 2014
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Ingår i: Artificial Organs. - : Wiley. - 0160-564X .- 1525-1594. ; 38:11, s. 945-953
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Tidskriftsartikel (refereegranskat)abstract
- The hemodialysis procedure involves contact between peripheral blood and the surface of dialyzer membranes, which may lead to alterations in the pathways of innate and adaptive immunity. We aimed to study the effect of blood-membrane interaction on human peripheral basophils and neutrophils in hemodialysis with high- and low-permeability polysulfone dialyzers. The surface expression of CD203c (basophil selection marker) and CD63 (activation marker) after activation by the bacterial peptide formyl-methionyl-leucyl-phenylalanine (fMLP) or anti-Fc epsilon receptor I (Fc epsilon RI) antibody and the absolute number of basophils was investigated before and after hemodialysis with each of the dialyzers. Moreover, the expression on neutrophils of CD11b, the CD11b active epitope, and CD88 was analyzed in the same groups of individuals. The expression of CD63 in basophils following activation by fMLP was significantly higher in the patient group compared with that in healthy controls, but no differences were observed after activation by anti-Fc epsilon RI. During the hemodialysis procedure, the low-flux membrane induced up-regulation of CD63 expression on basophils, while passage through the high-flux membrane did not significantly alter the responsiveness. In addition, the absolute number of basophils was unchanged after hemodialysis with either of the dialyzers and compared with healthy controls. We found no significant differences in the expression of the neutrophil activation markers (CD11b, the active epitope of CD11b, and CD88) comparing the two different dialyzers before and after dialysis and healthy controls. Together, these findings suggest that alterations in basophil activity may be a useful marker of membrane bioincompatibility in hemodialysis.
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| 3. |
- Aljadi, Zenib, et al.
(författare)
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Altered basophil function in patients with chronic kidney disease on hemodialysis
- 2017
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Ingår i: Clinical Nephrology. - : DUSTRI-VERLAG DR KARL FEISTLE. - 0301-0430. ; 88:2, s. 86-96
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Tidskriftsartikel (refereegranskat)abstract
- Aims: Chronic kidney disease (CKD) leads to impairment of immune cell function. Given the potential role of basophils in the pathogenesis of CKD, we aimed to study the basophil responsiveness towards microbial antigen exposure, judged as adhesion molecule expression and degranulation, in CKD patients on hemodialysis. Materials and methods: We selected markers linked to two crucial biological phases: the transmigration and degranulation processes, respectively. For the transmigration process, we selected the adhesion molecules CD11b, active CD11b epitope, and CD62L and for the degranulation process CD203c (piecemeal degranulation marker), CD63 (degranulation marker), and CD300a (inhibitory marker of degranulation). We measured basophil responsiveness after stimulation of different activation pathways in basophils using lipopolysaccharide (LPS), peptidoglycan (PGN), formyl-methyinoyl-leucyl-phenylalanine (fMLP), and anti-FceRI-ab. Results: The expression of CD63 in basophils following activation by fMLP was significantly higher in the patient group compared to matched healthy controls, but no differences were observed after activation by anti-Fc.RI. CD300a expression was significantly higher in patients following activation by fMLP and anti-Fc.RI, and the active epitope CD11b expression was significantly higher in patients after LPS activation. In addition, we found that CD62L was not shed from the cell surface after activation with LPS and fMLP. A slight downregulation was noted after activation with anti-Fc.RI in healthy controls. Conclusion: Together, these data demonstrate that basophil functions related to adhesion and degranulation are altered in CKD patients on hemodialysis, which indicates a potential role for the basophil in the pathogenesis of complications related to infections.
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| 4. |
- Aljadi, Zenib, et al.
(författare)
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Microfluidic Immunoaffinity Basophil Activation Test for Point-of-Care Allergy Diagnosis
- 2019
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Ingår i: Journal of Applied Laboratory Medicine (JALM). - : American Association for Clinical Chemistry. - 2475-7241 .- 2576-9456. ; 4:2, s. 152-163
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Tidskriftsartikel (refereegranskat)abstract
- Background: The flow cytometry-based basophil activation test (BAT) is used for the diagnosis of allergic response. However, flow cytometry is time-consuming, requiring skilled personnel and cumbersome processing, which has limited its use in the clinic. Here, we introduce a novel microfluidic-based immunoaffinity BAT (miBAT) method. Methods: The microfluidic device, coated with anti-CD203c, was designed to capture basophils directly from whole blood. The captured basophils are activated by anti-FceRI antibody followed by optical detection of CD63 expression (degranulation marker). The device was first characterized using a basophil cell line followed by whole blood experiments. Weevaluated the device with ex vivo stimulation of basophils in whole blood from healthy controls and patients with allergies and compared it with flow cytometry. Results: The microfluidic device was capable of capturing basophils directly from whole blood followed by in vitro activation and quantification of CD63 expression. CD63 expression was significantly higher (P = 0.0002) in on-chip activated basophils compared with nonactivated cells. The difference in CD63 expression on anti-FceRI-activated captured basophils in microfluidic chip was significantly higher (P = 0.03) in patients with allergies compared with healthy controls, and the results were comparable with flow cytometry analysis (P = 0.04). Furthermore, there was no significant difference of CD63% expression in anti-FceRI-activated captured basophils in microfluidic chip compared with flow cytometry. Conclusions: We report on the miBAT. This device is capable of isolating basophils directly from whole blood for on-chip activation and detection. The new miBAT method awaits validation in larger patient populations to assess performance in diagnosis and monitoring of patients with allergies at the point of care.
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| 5. |
- Almquist, Joachim, et al.
(författare)
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Model-Based Analysis Reveals a Sustained and Dose-Dependent Acceleration of Wound Healing by VEGF-A mRNA (AZD8601)
- 2020
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Ingår i: CPT. - : WILEY. - 2163-8306. ; 9:7, s. 384-394
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Tidskriftsartikel (refereegranskat)abstract
- Intradermal delivery of AZD8601, an mRNA designed to produce vascular endothelial growth factor A (VEGF-A), has previously been shown to accelerate cutaneous wound healing in a murine diabetic model. Here, we develop population pharmacokinetic and pharmacodynamic models aiming to quantify the effect of AZD8601 injections on the dynamics of wound healing. A dataset of 584 open wound area measurements from 131 mice was integrated from 3 independent studies encompassing different doses, dosing timepoints, and number of doses. Evaluation of several candidate models showed that wound healing acceleration is not likely driven directly by time-dependent VEGF-A concentration. Instead, we found that administration of AZD8601 induced a sustained acceleration of wound healing depending on the accumulated dose, with a dose producing 50% of the maximal effect of 92 mu g. Simulations with this model showed that a single dose of 200 mu g AZD8601 can reduce the time to reach 50% wound healing by up to 5 days.
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| 6. |
- Backteman, Karin, 1960-
(författare)
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T Cells and NK Cells in Coronary Artery Disease : Longitudinal and methodological studies in humans
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Coronary artery disease (CAD) is the leading cause of death worldwide and most often due to atherosclerosis. Atherosclerosis is a chronic inflammatory process that involves the arteries, inclouding those that supply blood to the heart muscle. Although inflammation is an important contributing factor to atherosclerosis, the mechanisms are not fully understood. One mechanism contributing to atherogenesis may involve some infectious microorganisms such as cytomegalovirus (CMV). In atherosclerosis, the arterial wall becomes infiltrated with lipids followed by different types of leukocytes and inflammatory mediators (atherogenesis). Leukocytes recirculate continuously between the blood and lymphoid organs, such as lymph nodes, where the adaptive immune response is started and regulated.The general aim of this thesis was to increase the understanding of associations between lymphocyte populations and different conditions of CAD (unstable and stable). To assess changes over time, a longitudinal follow up design was mostly used. Therefore, also perspectives of longitudinal variation were included in the thesis.Paper I showed that flow cytometric evaluation of lymphocyte populations is a robust technique that can be used in longitudinal studies, both in clinical and research settings. It was also shown that the time of sampling over the year did not have a major impact on the findings.In paper II, thoracic lymph nodes were investigated to assess whether CAD-associated changes were more prominent in comparison with blood. As expected, there were several major differences in lymphocyte composition between lymph nodes and blood. However, the analysis of thoracic lymph nodes did not reveal any further changes that were not detected in blood. Thus, blood is still the most reliable compartment for studies of lymphocyte populations in CAD since it is not possible to examine the local findings in the artery wall.Natural killer (NK) cells are innate lymphocytes with both regulatory and effector functions. In paper II and III we confirmed previous findings that CAD patients have lower proportions of NK cells in blood. However, the NK subtype and cytokine profile (paper III, measured by subtype markers and intra-cellular cytokine staining) did not differ between patients and controls. During a 12-month follow-up, the proportions of NK cells increased, although not in all patients. Failure to reconstitute NK cell levels was associated with several components of the metabolic syndrome and with a persistent low-grade inflammation as measured by plasma IL-6 levels. The findings support the notion of a protective role for NK cells in inflammation.CD4+ but not CD8+ T cells were significantly increased in patients with both unstable and stable conditions compared with healthy individuals (paper IV). Subpopulations of CD4+ T cells (CD4+CD28null) have previously been associated with CAD. However, we show that CD28null and CD28null57+ cells within the CD4+ and CD8+ T cell populations were similar in CAD patients and healthy controls. Instead, CMV seropositivity was the major determinant of expanded CD28null and CD57+ T cell fractions in both patients and healthy individuals. During the 1 year follow up the proportion of CD4+CD28null and CD8+CD28null cells increased in patients, which may reflect an accelerated immunological ageing occurring after the cardiac event.
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| 7. |
- Barck, Charlotte, et al.
(författare)
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Does nitrogen dioxide affect inflammatory markers after nasal allergen challenge?
- 2005
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Ingår i: American Journal of Rhinology. - : SAGE Publications. - 1050-6586 .- 1539-6290. ; 19:6, s. 560-566
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Exposure to high ambient levels of nitrogen dioxide (NO2) enhances the bronchial inflammatory reaction to allergen in humans. We tested whether this NO2 effect occurs also in the upper airways. METHODS: Sixteen allergic subjects with rhinitis and mild asthma were exposed at rest to either purified air or 500 microg/m3 NO2 for 30 minutes, followed 4 hours later by a nasal allergen challenge. Nasal lavage was performed before air/NO2 exposure, before allergen challenge, and 1, 4 and 18 hours after allergen challenge. Symptoms were recorded. RESULTS: The percentage of eosinophils and neutrophils, eosinophil cationic protein, and myeloperoxidase were similar after exposure to air + allergen and to NO2 + allergen. We noticed a tendency to increased sneezing the day after exposure to NO2 + allergen. CONCLUSION: The priming effect of an ambient brief NO2 exposure on subsequent allergic response was not noticeable in activation of inflammatory cells and mediators in the upper airways.
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| 8. |
- Hjortswang, Henrik, et al.
(författare)
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Infliximab in clinical routine : Experience with Crohn's disease and biomarkers of inflammation over 5 years
- 2009
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Ingår i: European Journal of Gastroenterology and Hepathology. - 0954-691X .- 1473-5687. ; 21:10, s. 1168-1176
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Infliximab was launched for the treatment of Crohn's disease (CD) in 1999. We set up a follow-up protocol to meticulously study disease development with repeated infusions of infliximab. Aim: To follow the effects of infliximab treatment on disease activity, blood chemistry, quality of life, plasma nitrite, and titers of Saccharomyces cerevisiae antibodies (ASCA). Methods: During 1999–2008, CD patients were monitored for disease activity by Harvey–Bradshaw index, blood chemistry with hemoglobin, albumin, C-reactive protein, platelet count, leukocyte count and creatinine, quality of life by the Short Health Scale, and plasma nitrite. During the first year of treatment, follow-up was done repeatedly before and 1 week after each infusion and thereafter every year before the last infusion for 5 years. ASCA was analyzed by flow cytometry with fluorescein isothiocyanate-labelled antibodies. Results: A total of 1061 infusions were given to 103 patients; 92 responders and 11 nonresponders. Responders were further monitored and Harvey–Bradshaw index decreased with infusions during the first year of treatment (P<0.0001), whereas hemoglobin (P<0.01) and albumin (P<0.001) increased, C-reactive protein (P<0.01) decreased, platelets (P<0.001) increased, and leukocytes (P<0.01) decreased. Creatinine was not affected. Short Health Scale (questions analyzed separately) decreased (P<0.0001), and nitrite (P<0.001) increased. During the next 4 years the improved values remained stable. Adverse effects were noted among 32% of the patients; local circulatory reactions being most common. No correlation between ASCA titers and inflammatory activity or infliximab treatment was found. Conclusion: Infliximab treatment is highly effective in responders and maintains symptomatic improvement and low inflammatory activity over years in CD patients.
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| 9. |
- Ivanoff, Jyrki, 1967-
(författare)
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Migration on extracellular matrix surface and infiltration into matrix - two distinguishable activities of human T cells
- 2003
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Migration of T-lymphocytes on a surface coated with extracellular matrix (ECM) components (two-dimensional (2-D) migration) and migration (infiltration) into a matrix (Three-dimesional (3-D) migration) are complex events and the underlying mechanisms are not yet fully understood. Here 2-D and 3-D migration were studied by use of seven leukemic T-cell lines representing discrete differentiation stages, a non-leukemic T-cell clone, and normal peripheral blood T cells. peripheral blood lymphocytes and the T-cell clone produced nanogram quantities of various chemokines, as compared to a production of ≤ 0.05 ng/ml by the T leukemia cell lines. In a Boyden chamber system, the leukemic T-cell lines showed haptotactic migration on fibronectin. The migration was augmented bu exposure to chemokines, including RANTES, MIP-1α, MIP-1β, and IL-8. The T-cell lines showed a peak response at a chemokine concentration of 10-50 ng/ml, whereas the T-cell clone responded optimally at 100 ng/ml. In contrast to a general capability of T-cells to migrate on 2-D ECM, only some of the T-cell lines were capable of 3-D migration into Matrigel or a collagen matrix. The infiltrative capacity was unrelated to the capacity to migrate on or adhere to the substrata. T-cell lines with a capacity to infiltrate produced matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), whereas non-infiltrating cell lines did not produce MMP-9. T-cell lines capable of infiltrating Matrigel or collagen responded to chemokines exposure with increased infiltration, but the chemokines did not render non-infiltrative cell lines infiltrative. Stimulation of infiltration of T-cell lines into collagen by the chemokine SDF-1α was inhibited by somatostatin, a neuropeptide with immunosuppressive properties. In conclusion, the ability to migrate on 2-D substrata and to infiltrate into 3.D substrata was found to be distinguishable properties of T cells. failure of some T-cell lines to infiltrate correlated with the lack of expression of MMP-9. Chemokines stimulated infiltration of infiltrative T-cell lines into collagen and Matrigel but did not render non-infiltrative T-cell lines infiltrative. Finally, a possible physiological mechanism for modulation of the chemokine-stimulated 3-D migration was demonstrated.
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| 10. |
- Kalm, Frida, et al.
(författare)
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Adhesion molecule cross-linking and cytokine exposure modulate IgE- and non-IgE-dependent basophil activation
- 2021
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Ingår i: Immunology. - : Wiley. - 0019-2805 .- 1365-2567. ; 162:1, s. 92-104
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Tidskriftsartikel (refereegranskat)abstract
- Basophils are known for their role in allergic inflammation, which makes them suitable targets in allergy diagnostics such as the basophil activation test (BAT) and the microfluidic immunoaffinity basophil activation test (miBAT). Beside their role in allergy, basophils have an immune modulatory role in both innate immunity and adaptive immunity. To accomplish this mission, basophils depend on the capability to migrate from blood to extravascular tissues, which includes interactions with endothelial cells, extracellular matrix and soluble mediators. Their receptor repertoire is well known, but less is known how these receptor–ligand interactions impact the degranulation process and the responsiveness to subsequent activation. As the consequences of these interactions are crucial to fully appreciate the role of basophils in immune modulation and to enable optimization of the miBAT, we explored how basophil activation status is regulated by cytokines and cross-linking of adhesion molecules. The expression of adhesion molecules and activation markers on basophils from healthy blood donors was analysed by flow cytometry. Cross-linking of CD203c, CD62L, CD11b and CD49d induced a significant upregulation of CD63 and CD203c. To mimic in vivo conditions, valid also for miBAT, CD62L and CD49d were cross-linked followed by IgE-dependent activation (anti-IgE), which caused a reduced CD63 expression compared with anti-IgE activation only. IL-3 and IL-33 priming caused increased CD63 expression after IgE-independent activation (fMLP). Together, our data suggest that mechanisms operational both in the microfluidic chip and in vivo during basophil adhesion may impact basophil anaphylactic and piecemeal degranulation procedures and hence their immune regulatory function.
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