腎細胞癌患者に対する術後補助療法としてのヒトγ型インターフェロン投与の長期免疫学的検討

Abstract

術前明らかな転移を有さない腎細胞癌患者33例に対し, 腎摘除術後, 予防的にIFN-γを投与し, three color flow cytometryを用いた投与前後の末梢血リンパ球サブセットの変動とNK活性値の変動を長期的に調べた. 1)IFN-γの投与により活性化細胞障害性リンパ球(ACTL)の比率は有意に高くなり, 逆にヘルパーTリンパ球(HTL)・サプレッサーインデューサーTリンパ球(SITL)の比率は有意に低下した.この変動は投与期間中長期間持続した. 2)NK活性値はIFN-γ投与により投与期間中持続的に投与前に比べ有意に高値を保っていた

Previously, we reported the short-term immunological effects of postoperative adjuvant interferon-gamma (IFN-gamma) administration to renal cell carcinoma patients as determined by three-color flow cytometry. We now report the results of a long-term study on a larger number of subjects. Thirty-three patients with renal cell carcinoma received a prophylactic intramuscular injection of IFN-gamma (300 x 10(4) units per week) after nephrectomy. We evaluated immunological changes by measuring peripheral blood lymphocyte subsets including activated cytotoxic T lymphocytes (ACTL), cytotoxic T lymphocytes (CTL), activated suppressor T lymphocytes (ASTL), helper T lymphocytes (HTL), activated suppressor-inducer T lymphocytes (AITL), and suppressor-inducer T lymphocytes (SITL). We also estimated the natural killer (NK) activity by a cytolytic test. All 33 patients were examined for at least 12 months after the start of IFN-gamma injection, and 18 patients were examined for 30 months including the 6-month period following discontinuation of IFN-gamma injection. We found significant enhancement of the ACTL subset from the second week to the sixth month after the start of IFN-gamma injection. On the other hand, we found a significant decrease in the percentage of the HTL and SITL subsets for a long time after the start of injection. NK activity significantly increased throughout the period of administration, and it continued to increase for six months after discontinuation of IFN-gamma injection.