Alexander J, Kaye P M
Clin Exp Immunol. 1985 Sep;61(3):674-82.
The effect of whole body sublethal gamma irradiation on the subsequent growth of Leishmania mexicana mexicana and Leishmania major was studied in CBA/Ca and BALB/c mice. Whereas BALB/c mice are highly susceptible to both parasites developing non healing progressively growing lesions at the site of cutaneous infection, CBA/Ca mice develop small healing cutaneous ulcers following subcutaneous infection with L. major but non healing lesions following subcutaneous infection with L.m. mexicana. Prior whole body sublethal irradiation of CBA/Ca mice, but not BALB/c mice, resulted in strong resistance against infection with L.m. mexicana: no lesions developed at the site of cutaneous infection. Irradiated BALB/c mice did, however, develop small lesions which healed when infected with L. major. The protective effects of irradiation coincided with the development of delayed type hypersensitivity. Both naive and sensitized nylon wool purified lymphocytes could restore susceptibility to L. major in irradiated BALB/c mice but only lymphocytes from long term infected donor mice adoptively transferred a non healing response to irradiated CBA/Ca mice infected with L.m. mexicana. Non-irradiated, L. major infected, CBA/Ca mice, but not similarly treated BALB/c mice, were found to be resistant to subsequent infection with L.m. mexicana. On the other hand, irradiated BALB/c mice infected with L. major were resistant to subsequent infectious challenge with L.m. mexicana. We suggest that the susceptibility of CBA/Ca mice to L.m. mexicana is under the control of an as yet unidentified gene which is not dependent on the generation of T suppressor cells and is bypassed by previous infection with L. major. Therefore, BALB/c mice immunized against L. major by prior sublethal irradiation are also resistant to L.m. mexicana.
在CBA/Ca和BALB/c小鼠中研究了全身亚致死剂量γ射线照射对墨西哥利什曼原虫和硕大利什曼原虫后续生长的影响。BALB/c小鼠对这两种寄生虫高度易感，在皮肤感染部位会形成不愈合的、逐渐增大的病变，而CBA/Ca小鼠在皮下感染硕大利什曼原虫后会形成小的愈合性皮肤溃疡，但在皮下感染墨西哥利什曼原虫后会形成不愈合的病变。对CBA/Ca小鼠而非BALB/c小鼠进行全身亚致死剂量照射后，会产生对墨西哥利什曼原虫感染的强大抵抗力：皮肤感染部位未出现病变。然而，经照射的BALB/c小鼠在感染硕大利什曼原虫时会形成小病变，这些病变会愈合。照射的保护作用与迟发型超敏反应的发展相一致。未致敏和致敏的尼龙毛纯化淋巴细胞都能恢复经照射的BALB/c小鼠对硕大利什曼原虫的易感性，但只有来自长期感染供体小鼠的淋巴细胞能将对感染墨西哥利什曼原虫的经照射CBA/Ca小鼠的不愈合反应过继转移。未照射的、感染了硕大利什曼原虫的CBA/Ca小鼠，而不是同样处理的BALB/c小鼠，被发现对随后的墨西哥利什曼原虫感染具有抵抗力。另一方面，感染了硕大利什曼原虫的经照射BALB/c小鼠对随后的墨西哥利什曼原虫感染性攻击具有抵抗力。我们认为，CBA/Ca小鼠对墨西哥利什曼原虫的易感性受一个尚未确定的基因控制，该基因不依赖于T抑制细胞的产生，并且在先前感染硕大利什曼原虫后会被绕过。因此，通过先前亚致死剂量照射对硕大利什曼原虫免疫的BALB/c小鼠对墨西哥利什曼原虫也具有抵抗力。
