We sought to determine if responsiveness to interleukin-21 (IL-21), a key cytokine for B cell differentiation, correlates with distinct clinical phenotypes in CVID.
Whilst statistical analysis of ELISA results showed significant differences between patients and healthy controls, in our set of patients functional tests yielded no evidence for an involvement of autoantibodies against BAFF, APRIL, or IL-21 in the pathogenesis of CVID or sIgAD.
Common variable immunodeficiency is associated with impaired in-vitro development of peripheral blood mononuclear cells or purified B-cells into memory or CD38 B-cells following addition of IL-21.