Reduced interleukin-5 production by peripheral CD4+ T cells in common variable immunodeficiency patients.

We evaluated the capacity of peripheral CD4+ T helper cells in four Common Variable Immunodeficiency (CVI) patients to secrete interleukin-4 (IL-4) and IL-5. While in control CD4+ T cells, stimulated via CD3 and cultured in presence of IL-2 or IL-15, a 10 fold increased production of IL-5 (146 +/- 30; 142 +/- 25 pg/ml) was found, a 4 fold increment of this cytokine was, instead, detected in 3 out of 4 CVI patients (34 +/- 13; 39 +/- 12 pg/ml) (p < 0.05). In conclusion, the reduction of IL-5, involved in the late regulation of B cell differentiation into Ig-secreting plasma cells, may contribute to the defective antibody production in CVI patients.