Monteón V M, Furuzawa-Carballeda J, Alejandre-Aguilar R, Aranda-Fraustro A, Rosales-Encina J L, Reyes P A
Departamento de Immunología, Instituto Nacional de Cardiología Ignacio Chávez, México City, Mexico.
Exp Parasitol. 1996 Aug;83(3):267-74. doi: 10.1006/expr.1996.0074.
American trypanosomiasis: In situ and generalized features of parasitism and inflammation kinetics in a murine model. Experimental Parasitology 83, 267-274. Mimicking the natural conditions of mammalian infection, metacyclic trypomastigote forms of a Mexican isolate (Ninoa) of Trypanosoma cruzi were inoculated into mice in order to study inflammation kinetics and parasite clearance at the inoculation site, parasite tropism to different organs, and local inflammatory cell infiltrates. Polymorphonuclear cells were detected at the inoculation site as early as 1 hr after inoculation. Peak cell infiltrate was observed at 24 hr; at 96 hr polymorphonuclear cells had disappeared. Mononuclear cell infiltrates began at 24 hr, peaking at Day 15, and then stared disappearing by Day 30. Antigens and parasites were detected by conventional techniques up to 15 min and thereafter became undetectable. Amplification of the hypervariable region of kinetoplast minicircle DNA by polymerase chain reaction was positive from 24 hr to Day 15, and the reaction became negative on Day 30. Myositis was observed in skeletal muscle from Days 7 to 180, it progressed from slight to severe, with an inflammation process which included macrophages, plasmatic cells, and a few eosinophils, the phenotype of the infiltrating cells included LyT2+ and LyT1+ on Day 30, and both cell populations decreased in parallel on Day 180. Antigen and parasite nests were present from Day 15 to 180; in muscle the earliest time at which minicircle DNA was detected was Day 7 and it was present until Day 180. Myocarditis was also observed; it developed from slight to severe in between Days 7 and 30, then gradually decreased, and cleared up. Mononuclear cell infiltrates in the myocardium were present from Days 7 to 180. Antigen and parasite nests were detected at Days 15 and 30 and disappeared at Day 180, although minicircle DNA was detected until the last day of observation. Both skeletal and heart muscles showed inflammatory reaction foci containing T. cruzi antigen. There was twice the number of foci in heart as in skeletal muscle. This ratio was maintained by Day 30; later skeletal muscle showed persistent inflammation which was practically cleared up in the heart. Parasites or antigen were not detected by Day 180 in both skeletal and cardiac muscle; however, minicircle DNA was amplified, indicating that an small proportion of parasites evaded immune response. According to these data, Mexican Ninoa Strain has a classification as biodeme 3.
小鼠模型中寄生虫感染及炎症动力学的原位和全身特征。《实验寄生虫学》83卷，267 - 274页。为研究炎症动力学、接种部位的寄生虫清除情况、寄生虫对不同器官的嗜性以及局部炎症细胞浸润，模拟哺乳动物自然感染条件，将克氏锥虫墨西哥分离株（尼诺阿株）的循环后期锥鞭毛体形式接种到小鼠体内。接种后1小时，接种部位即可检测到多形核细胞。24小时观察到细胞浸润达到峰值；96小时时多形核细胞消失。单核细胞浸润在24小时开始，第15天达到峰值，然后在第30天开始消失。采用常规技术可在15分钟内检测到抗原和寄生虫，此后则无法检测到。通过聚合酶链反应扩增动基体小环DNA的高变区，在24小时至第15天呈阳性，第30天反应变为阴性。在第7天至180天观察到骨骼肌出现肌炎，从轻度发展到重度，炎症过程包括巨噬细胞、浆细胞和少量嗜酸性粒细胞，浸润细胞的表型在第30天包括LyT2 +和LyT1 +，两种细胞群体在第180天同时减少。从第15天至180天存在抗原和寄生虫巢；在肌肉中最早检测到小环DNA的时间是第天，且一直持续到第180天。还观察到心肌炎；在第7天至30天之间从轻度发展到重度，然后逐渐减轻并消退。心肌中的单核细胞浸润在第7天至180天存在。在第15天和30天检测到抗原和寄生虫巢，在第180天消失，尽管在观察的最后一天仍可检测到小环DNA。骨骼肌和心肌均显示含有克氏锥虫抗原的炎症反应灶。心脏中的病灶数量是骨骼肌中的两倍。到第30天这个比例保持不变；之后骨骼肌显示持续炎症，而心脏中的炎症几乎消退。在第180天，骨骼肌和心肌中均未检测到寄生虫或抗原；然而，小环DNA可扩增，表明有一小部分寄生虫逃避了免疫反应。根据这些数据，墨西哥尼诺阿株分类为生物变种3。
