Oral Polio vaccination leads to oligoclonal expansion of TCRBV16+ and TCRBV13+ T cells in the colon of rhesus macaques

In studying immune responses towards the poliovirus, data about T cell mediated immunity in the intestine as the main portal of viral entry in disease and vaccination is lacking. We treated two macaques with oral Polio vaccine and collected duodenal and colonic biopsy specimens. RNA isolation, reverse transcription, and polymerase chain reaction were performed for fragment analysis of the complementarity determining region 3 (CDR3) of the T cell receptor beta chain variable region (TCRBV), followed by subcloning and sequencing of expanded bands. In the colon, oligoclonal expansions of TCRBV16+ or TCRBV13+ intestinal T cells with conserved motifs of the hypervariable CDR3 were found. Flow cytometric analysis of mucosal T cells revealed that activated colonic T cells were mainly CD4+. Our results indicate that there is a local activation of oligoclonal T cells in the colon after oral Polio vaccination (OPV) which involves selected TCRBV families and may occur within the CD4+ T cell subset.