Analysis of tissue lymphocytes by double fluorescent staining--gastric cancer tissue and regional lymph nodes.

An immunohistochemical study was performed on human lymphocytes in the tissue of gastric cancer, and also in the regional lymph nodes, by double fluorescent staining, using monoclonal antibodies. Leu3a+8+ cells (inducer T cells) which consist about 30 per cent of Leu 3a+ cells were seen in the tissue surrounding the gastric cancer. The other 70 per cent of Leu 3a+ cells were Leu3a+8- cells (helper T cells). In the lymph nodes they were noted in T cell areas in almost the same proportions, while in germinal centers, only Leu3a+8- cells were found. On the other hand, OKT8+Leu15- cells (cytotoxic T cells) were noted in a large number, while OKT8+Leu15+ cells (suppressor T cells) were few. Further, an increase of OKT8+Leu15- cells was seen around gastric cancer or metastatic cancer in lymph nodes. These immunohistochemical findings suggest that cytotoxic T cells are the main component in the tissue of gastric cancers and the regional lymph nodes. Increases in inducer T cells and helper T cells are probably required to induce cytotoxic T cells around the cancer tissue.