Abstract
Common variable immunodeficiency (CVID) is the most frequent form of primary hypogammaglobulinemia in adults. In addition to recurrent infections and respiratory manifestations, CVID patients may present several non-infection complications such as autoimmune diseases. The mechanisms that lead to immune dysregulation in CVID are not completely understood. Given the role of IgD on naïve B cells in the maintenance of tolerance and secreted IgD in the respiratory mucosa, we evaluated the frequency of IgD+ naïve and IgD+ memory B cells in CVID patients. Here, no differences were observed in the percentages and proliferative responses of anergic IgD+IgM-CD27- B cells between CVID patients, with or without autoimmune disease, and the control group. Interestingly, in the compartment of memory B cells, the percentage of IgD+IgM- cells was higher only in CVID patients with allergic rhinitis/allergic asthma. Our results may indicate that anergic IgD+IgM-CD27- B cells may not be compromised in our CVID cohort. However, IgD+IgM- memory B cells may play a role in the immunopathogenesis of allergic rhinitis/allergic asthma in CVID patients. Further studies are needed to better understand the participation of IgD+IgM- memory B cells in the immunopathogenesis of allergic rhinitis/allergic asthma in CVID patients.