Changes in CD45 isoform expression after influenza vaccination.
In this study, we report the changes in the isoforms of CD45 expressed on T lymphocytes after influenza vaccination. Young adults were compared to an elderly group (26 participants/group) after vaccination with influenza split-virus vaccine. Peripheral blood mononuclear cells (PBMC) obtained pre-vaccination and 6 and 12 weeks post-vaccination were cultured with live influenza virus. Unstimulated and stimulated (5-day culture with virus) PBMC were labelled with fluorescent monoclonal antibody markers for CD3, CD4, CD8, CD45RA and CD45RO. When compared to the young controls, the elderly group had a higher proportion of CD45RO+RA- and, reciprocally, a lower proportion of CD45RA+RO- cells. In spite of these differences, both groups showed a progressive increase in the proportion of CD45RA+ T lymphocytes (CD4+ and CD8+) following influenza vaccination. In vitro stimulation with influenza virus resulted in a decrease in the proportion of CD45RA+RO- with a concomitant increase in the CD45RA-RO- population, both of which were observed only at 6 weeks post-vaccination. Although the phenotype of classical memory cells for recall antigen is CD45RO+, these results suggest that memory for influenza split-virus vaccine, exists in the CD45RO- population. More importantly, it should be noted that in spite of the decline in CD45RA+ cells with aging, the elderly group showed similar changes in the proportions of all cell phenotypes in response to vaccination, and to subsequent in vitro re-exposure to the virus.
Division of Geriatric Medicine, University of Alberta, Edmonton, Canada.
J E
JE
McElhaney
M J
MJ
Pinkoski
G S
GS
Meneilly
D000328:Adult; D000368:Aged; D000375:Aging / Q000276:immunology*; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D066298:In Vitro Techniques; D007252:Influenza Vaccines / Q000276:immunology / Q000494:pharmacology*; D017493:Leukocyte Common Antigens / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009975:Orthomyxoviridae / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*
D007252:Influenza Vaccines; D017493:Leukocyte Common Antigens