Herpesvirus Antibodies Are Correlated With Greater Expression of p16 in the T Cells of Humans

Abstract

Background There is an increasing awareness that aging of the immune system, or immunosenescence, is a key biological process underlying many of the hallmark diseases of aging and age-related decline broadly. While immunosenescence can be in part due to normal age-related changes in the immune system, emerging evidence posits that viral infections may be biological stressors of the immune system that accelerate the pace of immunosenescence. Methods We used a convenience sample of 42 individuals aged 65 years and older to examine correlations between anti-viral IgG levels for four human herpesviruses (cytomegalovirus (CMV), herpes simplex virus (types 1 and 2), and Epstein-Barr virus) and multiple indicators of T cell immunosenescence. Results We found that most of the sample (n= 33) was anti-viral IgG positive for two or more of the four herpesvirus infections. We also examined correlations between both the total number of viruses for which an individual had anti-viral IgG and each individual virus, and multiple indicators of T cell immunosenescence, particularly p16 expression. The strongest correlations were observed between the total number of viruses for which an individual had detectable anti-viral IgG and p16 mean fluorescent intensity (MFI) among CD27-CD28-CD57+CD4+ cells (r=0.60, p< 0.001) and between anti-CMV IgG and p16 MFI of CD27-CD57+CD4+ cells (r=0.59, p<0.001). Conclusion Broadly, our findings offer compelling preliminary evidence for future investigations to incorporate multiple indicators of persistent viral infections, and a more comprehensive set of markers of T cell immunosenescence in population-based studies of aging.