Davis S W, Hammerberg B
Department of Microbiology, Pathology and Parasitology, North Carolina State University, College of Veterinary Medicine, Raleigh 27606.
Int J Parasitol. 1990 Aug;20(5):595-601. doi: 10.1016/0020-7519(90)90116-5.
The role of L3T4+ T lymphocytes in early primary infection with the metacestode of T. taeniaeformis was investigated by selective removal of these cells in vivo by parenteral injections with the rat monoclonal antibody (MAb) GK1.5 directed against the L3T4 molecule. Comparisons between treated and non-treated BALB/cByJ mice, normally resistant to infection with T. taeniaeformis, demonstrated that the treated mice had a greater percentage of viable parasites in the livers. Eosinophils were prominent in the region immediately surrounding parasite larvae in control mice, whereas treated mice showed virtually no eosinophil infiltration. Additionally, fewer tissue macrophages were evident near parasite larvae in the treatment group when compared to controls. The more susceptible C3H/HeDub strain mice demonstrated similar responses following treatment with the MAb, including diminished parasite killing and limited inflammatory cell infiltration. When C3H/HeDub mice were injected with the cytotoxic agent vinblastine sulfate, which has been shown to diminish Lyt-2+ suppressor cell activity, these mice remained unable to mount a strong local cellular response to the larval parasite. It is suggested that L3T4+ T lymphocytes play a crucial role in the innate resistance to T. taeniaeformis infection during the first 6 days post-infection. Effects seen following vinblastine treatment may be a result of drug-induced alterations in leukocyte chemotaxis, toxicity to other effector T cell populations, or a specific depletion of a functional Lyt-2+ T cell population that is required in addition to L3T4+ T cells for the expression of resistance to primary infection with T. taeniaeformis.
通过腹腔注射针对L3T4分子的大鼠单克隆抗体（MAb）GK1.5在体内选择性去除L3T4 + T淋巴细胞，研究了其在微小膜壳绦虫成虫早期原发感染中的作用。对通常对微小膜壳绦虫感染具有抵抗力的经处理和未处理的BALB/cByJ小鼠进行比较，结果表明，经处理的小鼠肝脏中活寄生虫的百分比更高。在对照小鼠中，嗜酸性粒细胞在寄生虫幼虫周围的区域很突出，而经处理的小鼠几乎没有嗜酸性粒细胞浸润。此外，与对照组相比，治疗组中寄生虫幼虫附近的组织巨噬细胞明显较少。更易感的C3H/HeDub品系小鼠在用单克隆抗体治疗后表现出类似的反应，包括寄生虫杀伤减少和炎症细胞浸润受限。当给C3H/HeDub小鼠注射细胞毒性剂硫酸长春碱时，硫酸长春碱已被证明可降低Lyt-2 +抑制细胞活性，这些小鼠仍然无法对幼虫寄生虫产生强烈的局部细胞反应。有人认为，L3T4 + T淋巴细胞在感染后第1天至6天对微小膜壳绦虫感染的天然抵抗力中起关键作用。长春碱治疗后出现的效应可能是药物诱导的白细胞趋化性改变、对其他效应T细胞群体的毒性，或功能性Lyt-2 + T细胞群体的特异性耗竭的结果，除了L3T4 + T细胞外，该群体对于表达对微小膜壳绦虫原发感染的抵抗力也是必需的。
