McDonald T L
J Natl Cancer Inst. 1983 Mar;70(3):493-7.
The enhancement of Moloney murine sarcoma virus (M-MuSV) tumor growth in BALB/c mice previously infected with lactate dehydrogenase virus (LDV) was shown to depend on the timing of the inoculations. Mice infected with LDV either 3 or 4 days prior to the M-MuSV inoculations demonstrated enhanced tumor growth, whereas mice infected simultaneously with LDV and M-MuSV or with LDV 30 days prior to M-MuSV challenge did not demonstrate M-MuSV tumor enhancement. Circulating immune complexes (CIC) were isolated from serum pools of LDV-infected mice. IgM-containing CIC were isolated only between 3 and 9 days post LDV infection. CIC containing IgG1 were isolated only between days 6 and 13, whereas IgG2--containing CIC were not detected until 18 days post LDV infection. Coincubation of isolated immune complexes (IC) with M-MuSV-sensitized cytotoxic lymphocyte-transformed and M-MuSV-transformed target cells produced a 56% reduction in M-MuSV-specific cytotoxicity, with LDV-antibody IC isolated from the sera of mice 11 days post LDV infection. CIC isolated from the sera of mice 5 days and 25 days after infection with LDV demonstrated 11 and 9% reductions in M-MuSV cytotoxicity, respectively. LDV-antibody IC composed of IgG1 antibody may act as blocking factors to M-MuSV-sensitized lymphocytes in vitro and may be responsible for the transient M-MuSV tumor enhancement observed in dually infected mice.
研究表明，在先前感染乳酸脱氢酶病毒（LDV）的BALB/c小鼠中，莫洛尼鼠肉瘤病毒（M-MuSV）肿瘤生长的增强取决于接种的时间。在接种M-MuSV前3天或4天感染LDV的小鼠表现出肿瘤生长增强，而同时感染LDV和M-MuSV或在M-MuSV攻击前30天感染LDV的小鼠则未表现出M-MuSV肿瘤增强。从感染LDV的小鼠血清池中分离出循环免疫复合物（CIC）。含IgM的CIC仅在LDV感染后3至9天被分离出来。含IgG1的CIC仅在第6至13天被分离出来，而含IgG2的CIC直到LDV感染后18天才被检测到。将分离出的免疫复合物（IC）与M-MuSV致敏的细胞毒性淋巴细胞转化细胞和M-MuSV转化的靶细胞共同孵育，结果显示，从LDV感染后11天的小鼠血清中分离出的LDV抗体IC使M-MuSV特异性细胞毒性降低了56%。从感染LDV后5天和25天的小鼠血清中分离出的CIC分别使M-MuSV细胞毒性降低了11%和9%。由IgG1抗体组成的LDV抗体IC在体外可能作为M-MuSV致敏淋巴细胞的阻断因子，并且可能是在双重感染小鼠中观察到的M-MuSV肿瘤短暂增强的原因。
