Analysis of the T Cell Receptor Variability of Tumor-Infiltrating Lymphocytes in Colorectal Carcinomas

While there is good clinical and experimental evidence for immunological tumor control in some tumors – malignant melanomas, for instance – the immunogenicity of colorectal carcinoma (CRC) still remains unsettled. We examined surgical specimens from 4 CRC patients for T cell clones among tumor-infiltrating lymphocytes (TIL). The growth of specific lymphocyte clones in a tumor indicates an immunological response in vivo. We used a T cell receptor Vβ family-specific semiquantitative PCR with additional sequencing to examine TIL for clonal expansion. In CRC, specific T cell clones could not be demonstrated. However, we observed a predominance of Vβ9 in 3 of 4 tumors.