Lima G M, Vallochi A L, Silva U R, Bevilacqua E M, Kiffer M M, Abrahamsohn I A
Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, Brazil.
Immunol Lett. 1998 Dec;64(2-3):145-51. doi: 10.1016/s0165-2478(98)00099-6.
The massive infiltration by polymorphonuclear leukocytes (PMN) soon after skin infection with Leishmania major suggests that PMN could participate in reducing parasite load and controlling the spreading of leishmanial infection. Yet, direct evidence for the participation of PMN in host defense against L. major was lacking. We investigated L. major infection in susceptible and resistant mice treated with the monoclonal (mAb) antibody RB6-8C5 that depletes the population of mature neutrophils and eosinophils. Both BALB/c and C57BL/6 mice depleted of PMN show accelerated parasite spreading and more severe footpad swelling than similarly infected untreated mice. In addition, significant higher parasite numbers were found in the lesion draining lymph nodes from PMN-depleted C57BL/6 mice. Histopathological analysis of the paw confirmed neutrophils containing ingested parasites as the dominant cell type in the infiltrate of the first days after infection and the nearly absolute neutrophil depletion in mAb-treated mice. Our data show the importance of PMN in early control of parasite load and parasitism spreading in cutaneous leishmaniasis.
在用硕大利什曼原虫感染皮肤后不久，多形核白细胞（PMN）会大量浸润，这表明PMN可能参与降低寄生虫负荷并控制利什曼原虫感染的扩散。然而，缺乏PMN参与宿主抵御硕大利什曼原虫的直接证据。我们研究了用单克隆（mAb）抗体RB6-8C5处理的易感和抗性小鼠中的硕大利什曼原虫感染，该抗体可耗尽成熟中性粒细胞和嗜酸性粒细胞群体。与未处理的类似感染小鼠相比，耗尽PMN的BALB/c和C57BL/6小鼠均表现出寄生虫扩散加速和足垫肿胀更严重。此外，在耗尽PMN的C57BL/6小鼠的病变引流淋巴结中发现寄生虫数量显著更高。爪的组织病理学分析证实，感染后第一天浸润中含有吞噬寄生虫的中性粒细胞是主要细胞类型，而在mAb处理的小鼠中几乎完全没有中性粒细胞。我们的数据表明PMN在皮肤利什曼病中早期控制寄生虫负荷和寄生虫扩散的重要性。
