T-cell receptor V beta gene expression differs in tumor-infiltrating lymphocytes within primary and metastatic melanoma.

Expression of T-cell receptor (TCR) gene rearrangements in tumor-infiltrating lymphocytes (TILs) within primary and metastatic melanoma specimens was studied. In order to analyze TCR gene transcription in TILs within these tissues, we analyzed reverse transcribed complementary DNA from mRNA directly from tissues using the polymerase chain reaction. The polymerase chain reaction-amplified products were confirmed by dot or Southern blot hybridization with C alpha or C beta oligoprobes. First, we investigated the diversity of TCR V alpha and V beta gene usage in human malignant melanoma patients with multiple metastasis. We found in one patient, bearing multiple skin lesions, that the patterns of TCR V alpha and V beta repertoires in different sites of the skin (leg and chest wall) were almost the same. However, in another patient with skin and brain melanomas, different TCR repertoires were presented. Next, we examined the usage of murine TCR V beta genes in TILs within the primary and metastatic sites (liver, lung, and brain) of C57BL/6 mice bearing B16-F10 murine melanoma. The population of TILs in each primary and metastatic site expressed from one to four TCR V beta genes. In each metastatic site, the profile of TCR V beta gene expression was different. A different TCR V beta usage in TILs distributed within metastases of various organs may reflect differences in tumor antigenicity at these sites or may be due to differential homing patterns to these tumors.