Defective cellular immune response in vitro in common variable immunodeficiency

Mononuclear cells from 39 patients with hypogammaglobulinemia of the common variable type were analyzed for in vitro proliferative responses to a panel of cell activators in order to examine the lymphocyte response to mitogens and to study the capacity to generate an immunologically specific secondary response. Patient lymphocyte response to phytohemagglutinin and concanavalin A was found to be significantly lower than that of controls studied in parallel (P<0.01), and low response did not correlate with T-lymphocyte number. Response to pokeweed mitogen was significantly lower than that of controls (P<0.01), but response to zinc, tested in a few patients, was normal. Strong depressions of patient lymphocyte proliferative responses to Candida albicans, Escherichia coli, and Staphylococcus aureus were observed (P<0.01); all of these microbial activators require intact B-cell function for maximum response. Repeated testing of individual patients indicated that poor lymphocyte response could be consistently observed. Examination of changes in in vitro lymphocyte response during clinical course and disease management showed that a consistent pattern of intrinsic lymphocyte functional deficiency could be demonstrated.