Profile of T-cell receptor V beta gene usage of cytotoxic T cells induced by intrapleural administration of a streptococcal preparation, OK432, in malignant effusions.

T-cell receptor (TCR) gene rearrangements were analyzed in tumor-infiltrating lymphocytes (TIL) using the reverse transcription-polymerase chain reaction (RT-PCR) to determine whether oligoclonal expression of TCRV beta occurs in TIL, and if so, whether it is involved in the clinical response and mechanisms of locoregional immunotherapy using a streptococcal preparation, OK432. Patients with malignant effusion of various origins were treated with intrapleural administration of OK432, and clinical responses were assessed by cytological and chest X-ray examinations. Pleural exudate cells (PEC), obtained before and after the administration of OK432 (designated as pre- and OK432-PEC, respectively), were subjected to TCR analysis. Both pre-PEC and OK432-PEC showed highly diverse expressions of TCRV beta gene usage in either type of PEC. The frequency of TCRV beta 20 gene expression in OK432-PEC was significantly higher than in pre-PEC. Moreover, the over-expression of the TCRV beta 20 gene usage was also induced in the peripheral blood lymphocytes and pre-PEC of patients by in vitro OK432 stimulation, but not in the PBL of one healthy volunteer. Single-strand conformational polymorphism (SSCP) analysis revealed the clonotypes of these TCRV beta 20 genes. Autologous tumor-specific killing activity could be detected in OK432-PEC and was significantly reduced by treatment with a TCRV beta 20-specific monoclonal antibody. These findings suggest that the rearrangement of TCRV beta 20 gene usage may be involved in the autologous tumor-specific action of malignant effusions in the treatment with OK432.