| 1. |
- Blom, M., et al.
(författare)
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Human eosinophils express, relative to other circulating leukocytes, large amounts of secretory 14-kD phospholipase A2
- 1998
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Ingår i: Blood. - 1528-0020. ; 91:8, s. 3037-3043
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Tidskriftsartikel (refereegranskat)abstract
- Human eosinophils perform several functions dependent on phospholipase A2 (PLA2) activity, most notably the synthesis of platelet-activating factor (PAF) and leukotriene C4 (LTC4). Several forms of PLA2 have been identified in mammalian cells. In the present study, the 14-kD, secretory form of PLA2 was detected in human eosinophils by immunocytochemical staining with the specific monoclonal antibody (MoAb) 4A1. In contrast, preparations of neutrophils, monocytes, lymphocytes, and basophils did not show detectable staining. With two MoAbs in a sandwich enzyme-linked immunosorbent assay (ELISA), large amounts of sPLA2 were detected in lysates of eosinophils, that were 20-fold to 100-fold higher than in the other circulating leukocytes (ie, neutrophils, basophils, monocytes, and lymphocytes). In addition, with a commercially available sPLA2 activity assay kit, we were able to show high activity of sPLA2 in human eosinophils relative to neutrophils. Investigations at the ultrastructural level showed that sPLA2 in eosinophils is mainly located in specific granules. Immunoelectron microscopy also visualized sPLA2 within phagosomes after addition of opsonized particles to the eosinophils. However, sPLA2 was not detected in the cell-free supernatants of activated eosinophils, in contrast to eosinophil-cationic protein (ECP), which colocalizes with sPLA2 in resting eosinophils. These findings warrant further studies into the role of sPLA2 in eosinophil function.
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| 2. |
- Tanner, L., et al.
(författare)
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Small-molecule-mediated OGG1 inhibition attenuates pulmonary inflammation and lung fibrosis in a murine lung fibrosis model
- 2023
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Interstitial lung diseases such as idiopathic pulmonary fibrosis (IPF) are caused by persistent micro-injuries to alveolar epithelial tissues accompanied by aberrant repair processes. IPF is currently treated with pirfenidone and nintedanib, compounds which slow the rate of disease progression but fail to target underlying pathophysiological mechanisms. The DNA repair protein 8-oxoguanine DNA glycosylase-1 (OGG1) has significant roles in the modulation of inflammation and metabolic syndromes. Currently, no pharmaceutical solutions targeting OGG1 have been utilized in the treatment of IPF. In this study we show Ogg1-targeting siRNA mitigates bleomycin-induced pulmonary fibrosis in male mice, highlighting OGG1 as a tractable target in lung fibrosis. The small molecule OGG1 inhibitor, TH5487, decreases myofibroblast transition and associated pro-fibrotic gene expressions in fibroblast cells. In addition, TH5487 decreases levels of pro-inflammatory mediators, inflammatory cell infiltration, and lung remodeling in a murine model of bleomycin-induced pulmonary fibrosis conducted in male C57BL6/J mice. OGG1 and SMAD7 interact to induce fibroblast proliferation and differentiation and display roles in fibrotic murine and IPF patient lung tissue. Taken together, these data suggest that TH5487 is a potentially clinically relevant treatment for IPF but further study in human trials is required.
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| 3. |
- Calafat, J, et al.
(författare)
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The bactericidal/permeability-increasing protein (BPI) is present in specific granules of human eosinophils
- 1998
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Ingår i: Blood. - 1528-0020. ; 91:12, s. 4770-4775
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Tidskriftsartikel (refereegranskat)abstract
- Eosinophils participate in the inflammatory response seen in allergy and parasitic infestation, but a role in host defense against bacterial infection is not settled. The bactericidal/permeability-increasing protein (BPI) has been demonstrated in neutrophils and it exerts bacteriostatic and bactericidal effects against a wide variety of Gram-negative bacterial species. Using the Western blot technique, a 55-kD band, corresponding to BPI, was detected in lysates from both neutrophils and eosinophils. The localization of BPI in immature and mature eosinophils was investigated using immunoelectron microscopy. BPI was found in immature and mature specific granules of eosinophils and was detected in phagosomes as well, indicating release of the protein from the granules into the phagosomes. Using a specific enzyme-linked immunosorbent assay, eosinophils were shown to contain 179 ng of BPI/5 x 10(6) eosinophils compared with 710 ng BPI/5 x 10(6) neutrophils. The presence of BPI in eosinophils suggests a role for these cells in host defense against Gram-negative bacterial invasion or may suggest a role for BPI against parasitic infestation.
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| 4. |
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| 6. |
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| 8. |
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| 9. |
- Eger, Katrien, et al.
(författare)
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The effect of the COVID-19 pandemic on severe asthma care in Europe : will care change for good?
- 2022
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Ingår i: ERJ Open Research. - : European Respiratory Society (ERS). - 2312-0541. ; 8:2
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Tidskriftsartikel (refereegranskat)abstract
- Background The coronavirus disease 2019 (COVID-19) pandemic has put pressure on healthcare services, forcing the reorganisation of traditional care pathways. We investigated how physicians taking care of severe asthma patients in Europe reorganised care, and how these changes affected patient satisfaction, asthma control and future care. Methods In this European-wide cross-sectional study, patient surveys were sent to patients with a physician-diagnosis of severe asthma, and physician surveys to severe asthma specialists between November 2020 and May 2021. Results 1101 patients and 268 physicians from 16 European countries contributed to the study. Common physician-reported changes in severe asthma care included use of video/phone consultations (46%), reduced availability of physicians (43%) and change to home-administered biologics (38%). Change to phone/video consultations was reported in 45% of patients, of whom 79% were satisfied or very satisfied with this change. Of 709 patients on biologics, 24% experienced changes in biologic care, of whom 92% were changed to home-administered biologics and of these 62% were satisfied or very satisfied with this change. Only 2% reported worsening asthma symptoms associated with changes in biologic care. Many physicians expect continued implementation of video/phone consultations (41%) and home administration of biologics (52%). Conclusions Change to video/phone consultations and home administration of biologics was common in severe asthma care during the COVID-19 pandemic and was associated with high satisfaction levels in most but not all cases. Many physicians expect these changes to continue in future severe asthma care, though satisfaction levels may change after the pandemic.
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| 10. |
- Egesten, A., et al.
(författare)
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Innate immunity – a clinical perspective
- 2019
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 11. |
- Gela, Anele, et al.
(författare)
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Eotaxin-3 (CCL26) exerts innate host defense activities that are modulated by mast cell proteases
- 2015
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Ingår i: Allergy. - : Wiley. - 1398-9995 .- 0105-4538. ; 70:2, s. 161-170
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundDuring bacterial infections of the airways, a Th1-profiled inflammation promotes the production of several host defense proteins and peptides with antibacterial activities including -defensins, ELR-negative CXC chemokines, and the cathelicidin LL-37. These are downregulated by Th2 cytokines of the allergic response. Instead, the eosinophil-recruiting chemokines eotaxin-1/CCL11, eotaxin-2/CCL24, and eotaxin-3/CCL26 are expressed. This study set out to investigate whether these chemokines could serve as innate host defense molecules during allergic inflammation. MethodsAntibacterial activities of the eotaxins were investigated using viable count assays, electron microscopy, and methods assessing bacterial permeabilization. Fragments generated by mast cell proteases were characterized, and their potential antibacterial, receptor-activating, and lipopolysaccharide-neutralizing activities were investigated. ResultsCCL11, CCL24, and CCL26 all showed potent bactericidal activity, mediated through membrane disruption, against the airway pathogens Streptococcus pneumoniae, Staphylococcus aureus, Nontypeable Haemophilus influenzae, and Pseudomonas aeruginosa. CCL26 retained bactericidal activity in the presence of salt at physiologic concentrations, and the region holding the highest bactericidal activity was the cationic and amphipathic COOH-terminus. Proteolysis of CCL26 by chymase and tryptase, respectively, released distinct fragments of the COOH- and NH2-terminal regions. The COOH-terminal fragment retained antibacterial activity while the NH2-terminal had potent LPS-neutralizing properties in the order of CCL26 full-length protein. An identical fragment to NH2-terminal fragment generated by tryptase was obtained after incubation with supernatants from activated mast cells. None of the fragments activated the CCR3-receptor. ConclusionsTaken together, the findings show that the eotaxins can contribute to host defense against common airway pathogens and that their activities are modulated by mast cell proteases.
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| 12. |
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| 13. |
- Mattsson, E, et al.
(författare)
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Superantigens from Staphylococcus aureus induce procoagulant activity and monocyte tissue factor expression in whole blood and mononuclear cells via IL-1 beta
- 2003
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Ingår i: Journal of Thrombosis and Haemostasis. - : Elsevier BV. - 1538-7933 .- 1538-7836. ; 1:12, s. 76-2569
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Staphylococcus aureus is one of the most common bacteria in human sepsis, a condition in which the activation of blood coagulation plays a critical pathophysiological role. During severe sepsis and septic shock microthrombi and multiorgan dysfunction are observed as a result of bacterial interference with the host defense and coagulation systems.OBJECTIVES: In the present study, staphylococcal superantigens were tested for their ability to induce procoagulant activity and tissue factor (TF) expression in human whole blood and in peripheral blood mononuclear cells.METHODS AND RESULTS: Determination of clotting time showed that enterotoxin A, B and toxic shock syndrome toxin 1 from S. aureus induce procoagulant activity in whole blood and in mononuclear cells. The procoagulant activity was dependent on the expression of TF in monocytes since antibodies to TF inhibited the effect of the toxins and TF was detected on the surface of monocytes by flow cytometry. In the supernatants from staphylococcal toxin-stimulated mononuclear cells, interleukin (IL)-1 beta was detected by ELISA. Furthermore, the increased procoagulant activity and TF expression in monocytes induced by the staphylococcal toxins were inhibited in the presence of IL-1 receptor antagonist, a natural inhibitor of IL-1 beta.CONCLUSIONS: The present study shows that superantigens from S. aureus activate the extrinsic coagulation pathway by inducing expression of TF in monocytes, and that the expression is mainly triggered by superantigen-induced IL-1 beta release.
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| 14. |
- Papareddy, Praveen, et al.
(författare)
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A human antithrombin isoform dampens inflammatory responses and protects from organ damage during bacterial infection
- 2019
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Ingår i: Nature Microbiology. - : Springer Science and Business Media LLC. - 2058-5276. ; 4:12, s. 2442-2455
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Tidskriftsartikel (refereegranskat)abstract
- Severe infectious diseases are often characterized by an overwhelming and unbalanced systemic immune response to microbial infections. Human antithrombin (hAT) is a crucial coagulation inhibitor with anti-inflammatory activities. Here we identify three hAT-binding proteins (CD13, CD300f and LRP-1) on human monocytes that are involved in blocking the activity of nuclear factor-kappa B. We found that the modulating effect is primarily restricted to the less abundant beta-isoform (h beta AT) of hAT that lacks N-glycosylation at position 135. Individuals with a mutation at this position have increased production of h beta AT and analysis of their blood, which was stimulated ex vivo with lipopolysaccharide, showed a decreased inflammatory response. Similar findings were recorded when heterozygotic mice expressing hAT or h beta AT were challenged with lipopolysaccharide or infected with Escherichia coli bacteria. Our results finally demonstrate that in a lethal E. coli infection model, survival rates increased when mice were treated with h beta AT one hour and five hours after infection. The treatment also resulted in a reduction of the inflammatory response and less severe organ damage.
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| 15. |
- Röckert Tjernberg, Anna, 1975-, et al.
(författare)
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Coeliac disease and invasive pneumococcal disease : a population-based cohort study
- 2017
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Ingår i: Epidemiology and Infection. - : Cambridge University Press. - 0950-2688 .- 1469-4409. ; 145:6, s. 1203-1209
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Tidskriftsartikel (refereegranskat)abstract
- Severe infections are recognized complications of coeliac disease (CD). In the present study we aimed to examine whether individuals with CD are at increased risk of invasive pneumococcal disease (IPD). To do so, we performed a population-based cohort study including 29 012 individuals with biopsy-proven CD identified through biopsy reports from all pathology departments in Sweden. Each individual with CD was matched with up to five controls (n = 144 257). IPD events were identified through regional and national microbiological databases, including the National Surveillance System for Infectious Diseases. We used Cox regression analyses to estimate hazard ratios (HRs) for diagnosed IPD. A total of 207 individuals had a record of IPD whereas 45/29 012 had CD (0.15%) and 162/144 257 were controls (0.11%). This corresponded to a 46% increased risk for IPD [HR 1.46, 95% confidence interval (CI) 1.05-2.03]. The risk estimate was similar after adjustment for socioeconomic status, educational level and comorbidities, but then failed to attain statistical significance (adjusted HR 1.40, 95% CI 0.99-1.97). Nonetheless, our study shows a trend towards an increased risk for IPD in CD patients. The findings support results seen in earlier research and taking that into consideration individuals with CD may be considered for pneumococcal vaccination.
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| 16. |
- Sorensen, OE, et al.
(författare)
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Processing of seminal plasma hCAP-18 to ALL-38 by gastricsin - A novel mechanism of generating antimicrobial peptides in vagina
- 2003
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Ingår i: Journal of Biological Chemistry. - 1083-351X. ; 278:31, s. 28540-28546
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Tidskriftsartikel (refereegranskat)abstract
- The human cathelicidin, hCAP-18, is expressed both in neutrophils and in epithelial cells. hCAP-18 is processed to the antimicrobial peptide LL-37 by proteinase 3 in neutrophils. hCAP-18 is highly expressed in the epididymis with a subsequent high concentration in seminal plasma where the protein is present in its unprocessed and antimicrobially inactive form. We report here that hCAP-18 in seminal plasma is processed to generate a 38-amino acid antimicrobial peptide ALL-38 by the prostate-derived protease gastricsin when incubated at a pH corresponding to the vaginal pH. In accordance with this, seminal plasma derived hCAP-18 was found in its processed form in the vagina following sexual intercourse. The antimicrobial activity of ALL-38 against a variety of microorganisms tested is equal to that of LL37. This enzymatic activation of a proantimicrobial substance in seminal plasma following exposure to the vaginal milieu represents a novel mechanism to prevent infection following sexual intercourse.
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| 17. |
- Tanner, Lloyd, et al.
(författare)
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Citrullination of extracellular histone H3.1 reduces antibacterial activity and exacerbates its proteolytic degradation
- 2021
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Ingår i: Journal of Cystic Fibrosis. - : Elsevier BV. - 1873-5010 .- 1569-1993. ; 20:2, s. 346-355
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Cystic fibrosis (CF), involves excessive airway accumulation of neutrophils, often in parallel with severe infection caused by Pseudomonas aeruginosa. Free histones are known to possess bactericidal properties, but the degree of antibacterial activity exerted on specific lung-based pathogens is largely unknown. Neutrophils have a high content of peptidyl deiminase 4 (PADI4), which citrullinate cationic peptidyl-arginines. In histone H3.1, several positions in the NH2-terminal tail are subject to citrullination.METHODS: Full-length and segmented histone subunit H3.1 was investigated for bactericidal activity towards P. aeruginosa (strain PAO1). PADI4-induced citrullination of histone H3.1 was assessed for antibacterial activity towards P. aeruginosa. Next, the effect of neutrophil elastase (NE)-mediated proteolysis of histone H3.1 was investigated. Finally, PADI4, H3.1, and citrullinated H3.1 were examined in healthy control and CF patient lung tissues.RESULTS: Full-length histone H3.1 and sections of the histone H3.1 tail, displayed bactericidal activity towards P. aeruginosa. These antibacterial effects were reduced following citrullination by PADI4 or proteolysis by NE. Interestingly, citrullination of histone H3.1 exacerbated NE-mediated degradation. In CF lung tissue, citrullinated histone H3.1 and PADI4 immunoreactivity was abundant. Degraded histone H3.1 was detected in the sputum of CF patients but was absent in the sputum of healthy controls.CONCLUSIONS: Citrullination impairs the antibacterial activity of histone H3.1 and exacerbates its proteolytic degradation by NE. Citrullination is likely to play an important role during resolution of acute inflammation. However, in chronic inflammation akin to CF, citrullination may dampen host defense and promote pathogen survival, as exemplified by P. aeruginosa.
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| 18. |
- Williams, Marc A., et al.
(författare)
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Allergic Inflammation: The Enemy Within
- 2011
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Ingår i: Journal of Innate Immunity. - : S. Karger AG. - 1662-811X .- 1662-8128. ; 3:2, s. 111-112
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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