title: Age-dependent increase of memory B cell response to cytomegalovirus in healthy adults.
abstract: Human cytomegalovirus (HCMV) may play an important role in immune system aging, due to its ability to modulate the host immune system. A significant age-related increase has been demonstrated for HCMV-specific serum antibody levels but so far, no information exists whether and to which extent the magnitude of the HCMV-specific memory B cell response develops with increasing age. We examined the size of the HCMV-specific memory B cell response and assessed whether there are quantitative differences in HCMV-specific memory B cell numbers and serum antibody titers against HCMV in young and older persons. The quantities of HCMV-specific memory B cells were determined in 20 young (20-31 years) and 21 older (60-80 years) healthy volunteers by limiting dilution analysis. HCMV-specific antibody levels were analyzed by ELISA. Our study demonstrates that higher HCMV-specific plasma antibody levels correlated well with the numbers of circulating HCMV-specific memory B cells and were not due to a generally higher antibody production in these individuals. The magnitude of HCMV-specific memory B cell responses was significantly higher in the group of older as compared to young subjects, but showed a high degree of individual variation in elderly persons. Together, the results of the present study indicate that the circulating memory B cell pool against HCMV increases during aging in humans. The expansion of HCMV-specific memory B cells and antibody titers possibly contribute to the sustained control of HCMV infection during old age.
authors.affiliation: Department of Virology, Medical University of Vienna, Vienna, Austria. judith.aberle@meduniwien.ac.at
authors.forename: Judith H
authors.initials: JH
authors.lastname: Aberle
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Puchhammer-Stöckl
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D000914:Antibodies, Viral / Q000097:blood; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000276:immunology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007156:Immunologic Memory / Q000502:physiology; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G