Subramanian C, Yu S, McKhann C F
Cancer Res. 1978 Jul;38(7):1996-2002.
Spleen cells from tumor-bearing mice when cultured for 3 to 5 days released a soluble factor into the media that suppressed the stimulation of lymph node and spleen cells by tumor antigen or mitogens. Spleens from mice bearing MC43 tumors for 14 days were capable of producing suppressor factor in vitro, while those from mice bearing the tumor for 10 days or less failed to do so. Lymph node cells from the same animals did not produce suppressor factor in vitro. The suppressor factor was produced by a nonadherent cell population, was heat stable, was lost on dialysis, and did not appear to be tumor antigen or thymidine.
荷瘤小鼠的脾细胞在培养3至5天时会向培养基中释放一种可溶性因子，该因子可抑制肿瘤抗原或丝裂原对淋巴结和脾细胞的刺激。携带MC43肿瘤14天的小鼠脾脏能够在体外产生抑制因子，而携带肿瘤10天或更短时间的小鼠脾脏则无法产生。同一动物的淋巴结细胞在体外不产生抑制因子。抑制因子由非贴壁细胞群体产生，具有热稳定性，透析后会丧失，且似乎不是肿瘤抗原或胸腺嘧啶核苷。
