Lopez P F, Parks W P, Lopez D M
J Natl Cancer Inst. 1984 Mar;72(3):725-32.
Purified tumor cell membrane (PTCM) fractions from spontaneous BALB/cfC3H mammary adenocarcinomas elicit blastogenic responses in spleen cells of tumor-bearing mice. Previous studies have demonstrated that splenic T-cells are the major responding cell population but have not clarified whether the antigens responsible for the reactions are exclusively viral in origin or may involve nonviral tumor-associated antigens (TAA). Pretreatment of PTCM preparations with polyvalent anti-murine mammary tumor virus (MuMTV) completely obliterated the ability of PTCM to stimulate an innocent bystander cytotoxicity reaction; however, it reduced the blastogenic response by only 60%, suggesting that the two assays may measure different antigenic reactivities. The specificity of the anti-MuMTV blocking for viral antigens was demonstrated by the complete absorption of the serum-blocking reaction with purified MuMTV particles in the cytotoxicity assay; however, absorption was only partial in the blastogenesis assay. Incubation with purified Rauscher murine leukemia virus particles failed to absorb the neutralizing effect of the sera. These data suggest that putative TAA can be detected in the blastogenesis assay but not in the cytotoxicity reaction. Ammonium sulfate-precipitated immunoglobulin fractions of sera from tumor-bearing BALB/cfC3H mice (TBMS) completely blocked the stimulatory potential of PTCM in both the blastogenesis and the cytotoxicity assays. In the reciprocal experiment to that described above, preabsorption of TBMS immunoglobulins with purified MuMTV completely removed the inhibition of the cytotoxicity but again only partially restored the blastogenic response. The reaction could be completely restored by preabsorption of TBMS with PTCM. These results support the contention of nonvirion antigen involvement in the blastogenesis reaction. In conclusion, these two assay systems detect different antigenic determinants on the MuMTV-expressing tumor cell membranes. Both viral and other antigens appear to be relevant in this model system, and serum factors present in the immunoglobulin fractions of tumor-bearing mice can inhibit T-cell responses directed at either kind of antigenic moieties.
来自自发性BALB/cfC3H乳腺腺癌的纯化肿瘤细胞膜（PTCM）组分可在荷瘤小鼠的脾细胞中引发增殖反应。先前的研究表明，脾T细胞是主要的反应细胞群体，但尚未阐明引发反应的抗原是否完全源自病毒，或者是否可能涉及非病毒性肿瘤相关抗原（TAA）。用多价抗小鼠乳腺肿瘤病毒（MuMTV）预处理PTCM制剂可完全消除PTCM刺激无辜旁观者细胞毒性反应的能力；然而，它仅使增殖反应降低了60%，这表明这两种检测方法可能测量的是不同的抗原反应性。在细胞毒性检测中，用纯化的MuMTV颗粒完全吸收血清阻断反应，证明了抗MuMTV对病毒抗原阻断的特异性；然而，在增殖检测中吸收只是部分的。用纯化的劳氏鼠白血病病毒颗粒孵育未能吸收血清的中和作用。这些数据表明，在增殖检测中可以检测到假定的TAA，但在细胞毒性反应中则检测不到。来自荷瘤BALB/cfC3H小鼠（TBMS）血清的硫酸铵沉淀免疫球蛋白组分在增殖和细胞毒性检测中均完全阻断了PTCM的刺激潜能。在与上述实验相反的实验中，用纯化的MuMTV预吸收TBMS免疫球蛋白可完全消除对细胞毒性的抑制，但同样仅部分恢复增殖反应。用PTCM预吸收TBMS可使反应完全恢复。这些结果支持了非病毒粒子抗原参与增殖反应的观点。总之，这两种检测系统检测到表达MuMTV的肿瘤细胞膜上不同的抗原决定簇。病毒和其他抗原在该模型系统中似乎都相关，并且荷瘤小鼠免疫球蛋白组分中存在的血清因子可抑制针对任何一种抗原部分的T细胞反应。
