LOW CD4 COUNTS RATHER THAN SUPERANTIGENIC-LIKE EFFECTS ACCOUNT FOR DIFFERENCES IN EXPRESSED T-CELL RECEPTOR (TCR) REPERTOIRES BETWEEN HIV-1SEROPOSITIVE LONG-TERM NONPROGRESSORS AND INDIVIDUALS WITH PROGRESSIVE DISEASE

Analysis of HIV-infected individuals who have stable CD4 counts many y ears after seroconversion may provide an insight as to how the host's immune system can successfully control HIV infection. In this study we analysed the T-cell receptor (TCR) V beta repertoire in 13 HIV+ indiv iduals, seven of whom were classed as long-term non-progressors (LTNP) , using a technique which couples anchor PCR (AnPCR) amplification of beta-chain cDNA to differential probe hyrbridization with non-radioact ively labelled VP family specific oligonucleotide probes. There were n o significant differences in the expressed TCR repertoires between the LTNP group and the other HIV-infected individuals. However, there was a statistically significant inverse correlation between CD4 count and the number of V beta family-specific perturbations in the recent sero converters (SC) and those with progressive infection (PI), consistent with other shared features of clinical disease progression (Th1/Th2 sw itch and high frequency of viral isolation). We conclude that long-ter m clinical nonprogression in HIV-1 infection is not associated with th e loss or expansion of a particular V beta family; instead, low CD4 co unt in the PI and SC individuals was correlated with increased number of V beta family-specific perturbations relative to the LTNP group and that it is hence unlikely that HIV encodes a superantigen.