DISSIMILAR TCR V-BETA FREQUENCIES IN TIL FROM DIFFERENT SITES OF THE SAME TUMOR

Tumor infiltrating lymphocytes (TIL) cultured long term in media containing IL-2 were shown to mediate in vitro and in vivo anti-tumor responses. To understand the anti-tumor activity of TIL T cells, we used polymerase chain reaction (PCR) to characterize the TCR Vbeta repertoire of ovarian TIL which were isolated from three tumor sites of the same patient at the same time and cultured under identical conditions, resulting in CD3+ cells with similar CD8:CD4 ratios. TIL isolated from ovary and ascites expressed a broad distribution of Vbeta repertoire, while the Vbeta phenotype of the TIL from a secondary tumor (omentum) was more restricted. After 5 months, cultured TIL from the primary tumor (ovary) maintained a diverse TCR Vbeta repertoire, but the Vbeta phenotype of TIL from the secondary site was dominated by the Vbeta-1, -11 and -14 families. Importantly, the percentages of Vbeta-11 and Vbeta-1 expression in both omentum and ovary TIL at 3 and 5 months was found to correlate with the levels of lysis of the tumor localized to omentum (p =0.003 and p=0.014, respectively). No statistical correlation was found between cytotoxicity and the use of any other individual Vbeta families or the sum of any other families, including TCR Vbeta-3 or -20 found increased at certain time points. This suggests that where certain TCR Vbeta families are selected in tumor reactive T cells this selection may reflect tumor Ag recognition at either primary or distant tumor sites. To our knowledge, this is the first documentation of complete TCR Vbeta repertoire of ovarian TIL and of a correlation between Vbeta usage and tumor lysis, by effectors from different sites.