Immunophenotypical alterations in a subset of patients with common variable immunodeficiency (CVID).

We investigated the expression of surface molecules on lymphocytes from 20 patients with CVID and 40 healthy subjects. Lymphocytes were analysed by dual colour flow cytometry. We identified a subset of patients (8 of 20) characterized by low CD4/CD8 ratio (less than 1.1), expansion of T cells co-expressing the activation marker HLA-DR and significant increase in CD8+ T cells co-expressing CD57. Expression of the adhesion molecules LFA-3 (CD58) and ICAM-1 (CD54) was significantly increased in this subgroup. In addition, within the CD4+ T cells the percentage of CD29+ (memory) cells was increased, while the CD45RA and LAM-1 (Leu-8) antigens were depressed. These results indicate that in a subgroup of CVID patients T cells are activated in vivo and the CD57+CD8+ lymphocyte subpopulation, supposed to comprise functional suppressor T cells, is expanded. We suggest a chronic viral infection in these patients, but it is not clear whether this is primary or secondary to the underlying defect.