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CD203c Expression (cd203c + expression)
Selected AbstractsComparison of basophil activation tests using CD63 or CD203c expression in patients with insect venom allergyALLERGY, Issue 9 2006B. Eberlein-König Background:, Flow cytometric basophil activation tests have been developed as cellular tests for in vitro diagnosis of IgE-mediated reactions. Different activation markers (CD63 or CD203c) with distinct ways of regulation have been used after stimulation with various allergens. Objective:, It was the aim of the present study to compare basophil activation tests by measuring both CD63 and CD203c upregulation in patients with insect venom allergy. Materials and methods:, 43 patients with a history of insect venom anaphylaxis were examined. A careful allergy history was taken, and skin tests and determination of specific IgE-antibodies were performed. Basophil activation tests (BAT) using CD63 or CD203c expression were done after stimulation with different concentrations of bee and wasp venom extracts. 25 healthy subjects with negative history of insect venom allergy were studied as controls. Results:, The CD203c protocol showed a slightly higher sensitivity than the CD63 protocol (97% vs. 89%) with regard to patients' history. The magnitude of basophil response was higher with CD203c in comparison to CD63 for both insect venoms. Specificity was 100% for the CD63 protocol and 89% for the CD203c protocol with regard to controls with negative history and negative RAST. Conclusion:, These results support the reliability of basophil activation tests using either CD63 or CD203c as cellular tests in the in vitro diagnosis of patients with bee or wasp venom allergy with a slightly higher sensitivity for the CD203c protocol. [source] An immunoglobulin E-reactive chimeric human immunoglobulin G1 anti-idiotype inhibits basophil degranulation through cross-linking of Fc,RI with Fc,RIIbCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2008S. J. Wigginton Summary Background IgE binds to mast cells and basophils via its high-affinity receptor, Fc,RI, and cross-linking of Fc,RI-bound IgE molecules by allergen leads to the release of allergic mediators characteristic of type I hypersensitivity reactions. Previous work has shown that cross-linking of Fc,RI with Fc,RIIb, an ITIM-containing IgG receptor, leads to inhibition of basophil triggering. 2G10, a chimeric human IgG1 anti-idiotype, has broad reactivity with human IgE and as such has the potential to bind simultaneously to Fc,RI-bound IgE, via its Fab regions, and the negative regulatory receptor, Fc,RIIb, via its Fc region. Objective To assess the ability of human 2G10 to inhibit anti-IgE and allergen-driven basophil degranulation through cross-linking of Fc,RI-bound IgE with Fc,RIIb. Methods 2G10 was assessed for its ability to bind to Fc,RIIb on transfected cells and on purified basophils. In the basophil degranulation assay, basophils were purified from peripheral blood of atopic individuals and activated with either anti-IgE or the house dust mite allergen Der p 1, in the presence or absence of human 2G10. Basophil activation was quantified by analysis of CD63 and CD203c expression on the cell surface, and IL-4 expression intracellularly, using flow cytometery. Results Human 2G10 was able to bind to Fc,RIIb on transfected cells and on purified basophils, and induce a dose-dependent inhibition of both anti-IgE and Der p 1-driven degranulation of basophils. Conclusion The inhibition of basophil degranulation by the human IgG1 anti-idiotype 2G10 highlights the therapeutic potential of IgE-reactive IgG antibodies in restoring basophil integrity through recruitment of the inhibitory receptor Fc,RIIb. [source] Evidence of in vivo basophil activation in chronic idiopathic urticariaCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2006K. Vasagar Summary Background Approximately 40% of chronic idiopathic urticaria (CIU) subjects have autoantibodies to either Fc,RI, or IgE. The effect of such autoantibodies on circulating basophil activation status is unknown. Objective The expression of cell surface activation markers on basophils from CIU, non-allergic, and allergic subjects were compared. Further, the relationship between marker expression and serum factors reported in CIU, such as histamine-releasing activity (HRA) and immunoreactivity to Fc,RI, were examined. Methods Peripheral blood was obtained from CIU, allergic, and non-allergic donors and fractionated by density gradients. Enriched basophils (1,12%) were analysed by flow cytometry for expression of activation markers including CD63, CD69, and CD203c. Dilutions of serum (5,50%) were analysed for HRA on basophils from a normal donor. Serum was tested for immunoreactivity by western blotting to a standard cell lysate prepared from an RBL-SX38 cell line transfected with human Fc,RI,. Results CIU subjects (n=9) and allergic subjects (n=8) exhibited enhanced expression of CD63 and CD69, as compared with non-allergic subjects (n=7); however, no difference was seen among groups for CD203c expression. Five CIU and two non-allergic subjects had evidence of significant serum HRA (>20%), whereas two CIU, two allergic, and three non-allergic subjects had evidence of serum immunoreactivity to Fc,RI,. Serum HRA and serum immunoreactivity to Fc,RI, were not associated with enhanced surface marker expression. Conclusion Basophil activation marker expression is increased in CIU subjects and is not associated with serum factors. In addition, serum HRA and Fc,RI, immunoreactivity are not unique to CIU, or related to enhanced circulating basophil marker expression. [source] | ||||||||||