Analysis of Epstein-Barr virus (EBV) receptor CD21 on peripheral B lymphocytes of long-term EBV- adults

Primary infections with EBV are rarely observed after the age of 20. Some i ndividuals even remain seronegative all their lives. Previously, a lack of EBV receptors on B cells of persistently EBV- adults was described as a rea son for long-term EBV-seronegativity. The present study examined the CD21 r eceptor status of 20 repeatedly EBV- healthy adults and 32 EBV- volunteers by means of flow cytometry. CD21 molecules on the surface of CD19(+) B cell s were quantified using anti-IgG-coated microbeads. The percentage of CD19( +)/CD21(+) B lymphocytes was slightly lower in the peripheral blood of EBV- donors, but the CD21 antibody binding capacity on CD19(+) B cells showed n o significant differences between EBV- and EBV+ adults. In vitro studies sh owed an equally good EBV transformability of peripheral B lymphocytes of EB V- and EBV+ donors. Since HLA-DR was recently described as a co-receptor fo r EBV infection of B cells, we also determined HLA-DRB1 alleles in the EBV- group. We found a significant negative association of EBV- seronegativity with HLA-DR13 in comparison with 111 healthy blood donors. In summary, a bi ologically significant lack of the EBV receptor CD21 on peripheral B lympho cytes of persistently EBV- adults was excluded as a reason for long-term EB V-seronegativity.