Functional tests of B cells are independent of EUROclass classification in CVID patients
| Authors | |
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| Year of publication | 2019 |
| Type | Conference abstract |
| MU Faculty or unit | |
| Citation | |
| Description | METHODOLOGY: B cells from 31 CVID patients and 21 healthy donors were stimulated through T dependent and T independent signaling pathway in vitro. The ability of differentiation, proliferation, expression of inhibitory Fc?IIB receptor (CD32B), IL-10 receptor (CD210) and IL-10 production was measured by eight color flow cytometry after a seven-day incubation. The production of isotype switched immunoglobulins was determined by ELISA method. RESULTS: We observed an increased frequency of naive B cells and decreased frequency of memory B cells and plasmablasts in CVID patients when compared to healthy donors. Proliferation was reduced in CD21low B cells and plasmablasts, whereas naive and memory B cells showed normal proliferative activity. The expression of inhibitory Fc?IIB receptor in CVID patients was comparable to healthy donors among all B cell subsets with an exception of increased CD32B expresion on CD21low B cells. It is plausible that low concentrations of IgG in CVID patients may lead to the restriction of CD32B inhibitory effect in CD21low B cell development. In one CVID patient, we revealed significantly higher expression of CD32B on marginal zone B cells and plasmablasts after T dependent stimulation. This patient is undergoing detailed research of CD32B gene. The expression of IL-10 receptor was slightly increased in plasmablasts, marginal zone B cells and CD21low B cells. Production of IL-10 was decreased among all B cell subsets after T independent stimulation, but after T dependent stimulation only plasmablasts produced less IL-10. CONCLUSION: A diverse ability of B cell differentiation into plasmablast stage was observed in CVID patients. This ability was independent of the EUROclass classification. |