Baek B K, Islam M K, Kim B S, Lim C W, Hur J, Oluoch A O, Kim C H, Kakoma I
College of Veterinary Medicine, Chonbuk National University, 561-756, Chonju, South Korea.
Vet Parasitol. 2003 May 1;113(3-4):217-27. doi: 10.1016/s0304-4017(03)00085-2.
The protective response in rats against a homologous challenge infection with Strongyloides venezuelensis was characterized. In an initial infection with 1000 filariform larvae and migrating larvae (L(3)) of S. venezuelensis, the population of L(3) in the lungs on day 3 postinfection (PI), and that of adult worms in the small intestine on day 7 PI, were 180.8+/-14.5 and 336.8+/-70.7, respectively. The latter were gradually expelled towards day 42 PI. After the initial infection, the rats developed strong immunity against a homologous challenge infection as manifested by a marked reduction in worm populations, stunted body length and width, damage to reproductive organs, impaired egg production and rapid expulsion of the worms by day 14 after challenge. Expulsion of the worms was preceded by a significantly elevated (P<0.05) peripheral blood eosinophil (PBE) count, both in the initial (200.0+/-26.5 x 10(3)ml) and the challenge infection (400.9+/-165.4 x 10(3)ml). These findings suggest that rats acquire strong homologous immunity following initial exposure to S. venezuelensis. It is suggested that PBEs are involved in worm expulsion. A major target of these effector mechanisms is the reproductive system of S. venezuelensis.
对大鼠针对委内瑞拉类圆线虫同源攻击感染的保护性反应进行了表征。在用1000条委内瑞拉类圆线虫丝状幼虫和迁移幼虫（L(3)）进行初次感染时，感染后第3天（PI）肺中L(3)的数量，以及感染后第7天小肠中成虫的数量，分别为180.8±14.5和336.8±70.7。后者在感染后第42天逐渐被排出。初次感染后，大鼠对同源攻击感染产生了强大的免疫力，表现为虫体数量显著减少、体长和体宽发育迟缓、生殖器官受损、产卵量受损以及在攻击后第14天虫体迅速被排出。在虫体排出之前，初次感染（200.0±26.5×10(3)/ml）和攻击感染（400.9±165.4×10(3)/ml）时外周血嗜酸性粒细胞（PBE）计数均显著升高（P<0.05）。这些发现表明，大鼠在初次接触委内瑞拉类圆线虫后获得了强大的同源免疫力。提示PBE参与了虫体排出。这些效应机制的一个主要靶点是委内瑞拉类圆线虫的生殖系统。
