Fell A H, Preston P M
Division of Biological Sciences, University of Edinburgh, Scotland, U.K.
Int J Parasitol. 1992 Jul;22(4):491-501. doi: 10.1016/0020-7519(92)90150-j.
Bovine cells infected with macroschizonts of the protozoan parasites Theileria annulata and Theileria parva formed solid tumours when injected into irradiated Balb/c and irradiated Balb/c nude mice. T. annulata tumours grew more vigorously than T. parva tumours, when initiated with similar doses of infected cells in mice exposed to the same doses of gamma-irradiation. In irradiated Balb/c mice, tumours of both species of parasites began to regress 2-3 weeks after injection of cells but grew without regression in irradiated Balb/c nude mice. Haemorrhage and necrosis of tumours, induced by macrophages and neutrophils, were seen in both mouse strains but were insufficient to cause regression in Balb/c nude mice. Theileria-infected bovine cells failed to establish in C57 beige mice, which lack functional natural killer (NK) cells. Flow cytometry, using monoclonal antibodies to murine leukocyte/lymphocyte antigens, showed that the radiation dose required to allow establishment of T. annulata tumours in Balb/c mice caused a severe depletion of splenic lymphocytes. B cells, helper T and cytotoxic T cells showed differing levels of susceptibility to irradiation. The presence of a tumour promoted the recovery of lymphocyte populations: this recovery was accompanied by destruction of the tumour.
感染了原生动物寄生虫环形泰勒虫和小泰勒虫大裂殖体的牛细胞，注射到经辐照的Balb/c小鼠和经辐照的Balb/c裸鼠体内后会形成实体瘤。当在接受相同剂量γ射线照射的小鼠中，用相似剂量的感染细胞启动肿瘤形成时，环形泰勒虫肿瘤比小泰勒虫肿瘤生长得更旺盛。在经辐照的Balb/c小鼠中，两种寄生虫的肿瘤在注射细胞后2 - 3周开始消退，但在经辐照的Balb/c裸鼠中肿瘤持续生长而不消退。在两种小鼠品系中均可见到由巨噬细胞和中性粒细胞诱导的肿瘤出血和坏死，但这不足以导致Balb/c裸鼠的肿瘤消退。感染泰勒虫的牛细胞在缺乏功能性自然杀伤（NK）细胞的C57米色小鼠中无法形成肿瘤。使用针对小鼠白细胞/淋巴细胞抗原的单克隆抗体进行的流式细胞术分析表明，在Balb/c小鼠中使环形泰勒虫肿瘤形成所需的辐射剂量导致脾淋巴细胞严重耗竭。B细胞、辅助性T细胞和细胞毒性T细胞对辐射的敏感性不同。肿瘤的存在促进了淋巴细胞群体的恢复：这种恢复伴随着肿瘤的破坏。
