CD79A and common variable immunodeficiency: First, as one would expect, the numbers of IgA+ SM B cells were closely correlated with the numbers of total isotype class SM B cells in 94 CVID subjects, again shown in these groups (P = 0.0001) (Fig. 3 B), as well as with the baseline level of serum IgA concentrations of the same patients, (P = 0.002) (Fig. 3 C).