As class-switched IgD B cells have been implicated in the respiratory mucosa [32], we evaluated this subset in CVID patients with respiratory manifestations (allergic rhinitis, asthma, and chronic sinusitis) and observed a higher percentage of IgD+IgM− CD27+ B cells in these patients compared with the control group (Figure 2C). The gene discussed is CD40LG; the disease is chronic rhinosinusitis.