| 1. |
|
|
| 2. |
- Arkestål, Kurt, et al.
(författare)
-
Impaired allergy diagnostics among parasite-infected patients caused by IgE antibodies to the carbohydrate epitope galactose-alpha 1,3-galactose
- 2011
-
Ingår i: Journal of Allergy and Clinical Immunology. - : Elsevier BV. - 0091-6749 .- 1097-6825. ; 127:4, s. 1024-1028
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The carbohydrate epitope galactose-alpha 1,3galactose (a-Gal) is abundantly expressed on nonprimate mammalian proteins. We have recently shown that alpha-Gal is responsible for the IgE binding to cat IgA, a newly identified cat allergen (Fel d 5). Objective: We sought to investigate the diagnostic relevance of IgE antibodies to Fel d 5 and a-Gal among parasite-infected patients from central Africa without cat allergy compared with patients with cat allergy from the same region. Methods: Sera from 47 parasite-infected patients and 31 patients with cat allergy were analyzed for total IgE and IgE antibodies against cat dander extract (CDE) by using the ImmunoCAP system. Inhibition assay was performed with a-Gal on solid phase-bound CDE. The presence of IgE specific for the major cat allergen Fel d 1, Fel d 5, and alpha-Gal was analyzed by means of ELISA. Results: Among the 47 parasite-infected patients, 85% had IgE antibodies against alpha-Gal (OD; median, 0.175; range, 0.1021.466) and 66% against Fel d 5 (OD; median, 0.13; range, 0.1031.285). Twenty-four of the parasite-infected patients were sensitized to CDE, and 21 of them had IgE antibodies to Fel d 5 and a-Gal. There was no correlation between IgE levels to CDE and rFel d 1 among the parasite-infected patients but a strong correlation between CDE and Fel d 5 and alpha-Gal (P <. 001). Among the group with cat allergy, only 5 patients had IgE to alpha-Gal, and nearly 75% (n 5 23) had IgE to rFel d 1 (median, 7.07 kU(A)/L; range, 0.51-148.5 kUA/ L). In contrast, among the patients with cat allergy, there was a correlation between IgE levels to CDE and rFel d 1 (P <.05) but no correlation between CDE and Fel d 5 and alpha-Gal. Conclusion: IgE to alpha-Gal causes impaired allergy diagnostics in parasite-infected patients. Screening for IgE to rFel d 1 and other allergens without carbohydrates might identify patients with true cat sensitization/ allergy in parasite-infested areas.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Gendrin, Claire, et al.
(författare)
-
Mast cell chymase decreases the severity of group B Streptococcus infections
- 2018
-
Ingår i: Journal of Allergy and Clinical Immunology. - : Elsevier BV. - 0091-6749 .- 1097-6825. ; 142:1, s. 120-129
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Group B Streptococcus (GBS) or Streptococcus agalactiae are β-hemolytic gram-positive bacteria that colonize the lower genital tracts of women and are frequently associated with infections during pregnancy. Innate immune defenses are critical for controlling GBS dissemination and systemic infection. Mast cells are resident sentinel cells that come into contact with pathogens early during colonization and infection.OBJECTIVE: We aimed to investigate the contribution of chymase to systemic GBS infection and rates of preterm birth.METHODS: Pharmacologic and genetic approaches using mice deficient in mast cell protease (MCPT) 4, the mouse functional homologue of human chymase, were used.RESULTS: Our studies show that mast cells release a protease with chymotrypsin-like cleavage specificity in response to GBS. Additionally, increased GBS systemic infection and preterm births were observed in MCPT4-deficient mice versus MCPT4-sufficient mice. Furthermore, we observed that proteolytic cleavage of the host extracellular matrix protein fibronectin by peritoneal cell-derived mast cell lysates diminished GBS adherence. Consistent with this observation, the increase in GBS dissemination and preterm births observed in MCPT4-deficient mice was abolished when GBS was deficient in expression of the fibronectin-binding protein SfbA.CONCLUSIONS: Taken together, our results suggest that the protective effect of MCPT4 against GBS dissemination and preterm labor can be attributed in part to MCPT4-mediated proteolysis of fibronectin. Our studies reveal a novel role of mast cells in defense against bacterial infections.
|
|
| 6. |
- Hultberg, Jonas, et al.
(författare)
-
Plasma protein profiling reflects T(H)1-driven immune dysregulation in common variable immunodeficiency
- 2020
-
Ingår i: Journal of Allergy and Clinical Immunology. - : MOSBY-ELSEVIER. - 0091-6749 .- 1097-6825. ; 146:2, s. 417-428
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Common variable immunodeficiency (CVID) is a disorder characterized by antibody deficiency. A significant fraction of the patients suffer from immune dysregulation, which leads to increased morbidity and mortality. The pathogenesis of this condition is poorly understood. Objective: Our aim was to find out whether the plasma protein signature in CVID is associated with clinical characteristics and lymphocyte aberrations. Methods: A highly sensitive proximity extension assay was used for targeted profiling of 145 plasma proteins in 29 patients with CVID. Phenotyping of peripheral lymphocytes was done by flow cytometry. The findings were correlated with the burden of immune dysregulation. Results: Unsupervised clustering of plasma protein profiles identified 2 distinct groups of patients with CVID that differed significantly in terms of the degree of complications due to immune dysregulation and in terms of the frequency of activated B- and T-cell subpopulations. Pathway analysis identified IFN-gamma and IL-1 beta as the top enriched upstream regulators associated with higher grade of immune dysregulation. In addition, CVID was found to be associated with increased plasma levels of the B-cell attracting chemokine CXCL13. Conclusion: Clustering based on plasma protein profiles delineated a subgroup of patients with CVID with activated T cells and clinical complications due to immune dysregulation. Thus, data indicate that CVID-associated immune dysregulation is a T(H)1-mediated inflammatory process driven by the IFN-gamma pathway.
|
|
| 7. |
- Konya, Viktoria, et al.
(författare)
-
Vitamin D downregulates the IL-23 receptor pathway in human mucosal group 3 innate lymphoid cells
- 2018
-
Ingår i: Journal of Allergy and Clinical Immunology. - : MOSBY-ELSEVIER. - 0091-6749 .- 1097-6825. ; 141:1, s. 279-292
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Vitamin D deficiency is a risk factor for inflammatory bowel disease (IBD). The IL-23-driven tissue-resident group 3 innate lymphoid cells (ILC3s) play essential roles in intestinal immunity, and targeting IL-23/12 is a promising approach in IBD therapy. Objective: We set out to define the role of 1 alpha,25-dihydroxy vitamin D3 (1,25D) in regulating functional responses of human mucosal ILC3s to IL-23 plus Il-1 beta stimulation. Methods: Transcriptomes of sorted tonsillar ILC3s were assessed by using microarray analysis. ILC3 cytokine production, proliferation, and differentiation were determined by means of flow cytometry, ELISA, and multiplex immunoassay. Intestinal cell suspensions and ILC3s sorted from gut biopsy specimens of patients with IBD were also analyzed along with plasma 25-hydroxy vitamin D3 (25D) detection. Results: ILC3s stimulated with IL-23 plus IL-1 beta upregulated the vitamin D receptor and responded to 1,25D with downregulation of the IL-23 receptor pathway. Consequently, 1,25D suppressed IL-22, IL-17F, and GM-CSF production from tonsillar and gut ILC3s. In parallel, 1,25D upregulated genes linked to the IL-1 beta signaling pathway, as well as the IL-1 beta-inducible cytokines IL-6, IL-8, and macrophage inflammatory protein IL/1 beta. The 1,25D-triggered skewing in ILC3 function was not accompanied or caused by changes in viability, proliferation, or phenotype. Finally, we confirmed low 25D plasma levels in patients with IBD with active inflammation. Conclusion: In light of the beneficial targeting of IL-23/12 in patients with IBD, 1,25D appears as an interesting therapeutic agent that inhibits the IL-23 receptor pathway, providing a novel mechanism for how ILC3s could be manipulated to regulate intestinal inflammation.
|
|
| 8. |
- Levi-Schaffer, Francesca, et al.
(författare)
-
Selected recent advances in understanding the role of human mast cells in health and disease
- 2022
-
Ingår i: Journal of Allergy and Clinical Immunology. - : Elsevier. - 0091-6749 .- 1097-6825. ; 149:6, s. 1833-1844
-
Forskningsöversikt (refereegranskat)abstract
- Mast cells are highly granular tissue-resident cells and key drivers of inflammation, particularly in allergies as well as in other inflammatory diseases. Most mast cell research was initially conducted in rodents but has increasingly shifted to the human system, with the advancement of research technologies and methodologies. Today we can analyze primary human cells including rare subpopulations, we can produce and maintain mast cells isolated from human tissues, and there are several human mast cell lines. These tools have substantially facilitated our understanding of their role and function in different organs in both health and disease. We can now define more clearly where human mast cells originate from, how they develop, which mediators they store, produce de novo, and release, how they are activated and by which receptors, and which neighboring cells they interact with and by which mechanisms. Considerable progress has also been made regarding the potential contribution of mast cells to disease, which, in turn, has led to the development of novel approaches for preventing key pathogenic effects of mast cells, heralding the era of mast cell-targeted therapeutics. In this review, we present and discuss a selection of some of the most significant advancements and remaining gaps in our understanding of human mast cells during the last 25 years, with a focus on clinical relevance.
|
|
| 9. |
|
|
| 10. |
|
|
