Vlaminck Johnny, Borloo Jimmy, Vercruysse Jozef, Geldhof Peter, Claerebout Edwin
Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke B-9820, Belgium.
Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke B-9820, Belgium.
Int J Parasitol. 2015 Mar;45(4):209-13. doi: 10.1016/j.ijpara.2014.11.001. Epub 2014 Dec 13.
With the increasing incidence of anthelmintic resistance worldwide, immunological control of worm infections through vaccination is often put forward as a rational and cost-effective alternative for anthelmintic drugs. In this study we report on the evaluation of a double-domain activation-associated secreted protein purified from the excretory-secretory material of the adult stage of the small intestinal parasite Cooperia oncophora as a vaccine antigen against this parasite. In a first experiment, calves were vaccinated three times i.m. with activation-associated secreted protein and Quil A adjuvant or with adjuvant alone, and subsequently challenged with a trickle infection of 25,000 infective larvae in total over 25 days. Vaccinated calves showed a significant reduction of 91% in their cumulative faecal egg counts and a significantly higher number of inhibited L4s present in their intestine compared with control animals. Furthermore, both female and male adult worms were significantly smaller in the vaccinated group than in the control group. In a second experiment, the vaccine antigen was further evaluated under field conditions. Calves were immunised as described above, followed by a natural challenge infection on pasture. Cooperia oncophora faecal egg counts in the vaccinated animals were reduced during the entire grazing period, resulting in a significant reduction in the cumulative faecal egg counts of 58.5%. Numbers of infective C. oncophora larvae were lower on plots grazed by vaccinated calves, with a reduction in mean pasture larval counts of 65% at housing. A significant reduction of 81.6% in total numbers of C. oncophora worms was shown in the vaccinated group compared with the control group. Taken together, the data highlight the protective capacity of the double-domain activation-associated secreted protein and the possibility of controlling C. oncophora infections through vaccination.
随着全球范围内抗蠕虫药耐药性的日益增加，通过疫苗接种对蠕虫感染进行免疫控制常被视为抗蠕虫药的一种合理且具有成本效益的替代方法。在本研究中，我们报告了对从小肠寄生虫柯氏原圆线虫成虫期排泄分泌物质中纯化的双结构域活化相关分泌蛋白作为针对该寄生虫的疫苗抗原的评估。在第一个实验中，给小牛肌肉注射三次活化相关分泌蛋白和Quil A佐剂或仅注射佐剂，随后在25天内分批次感染总共25,000条感染性幼虫。与对照动物相比，接种疫苗的小牛粪便累计虫卵计数显著降低了91%，并且其肠道内存在的被抑制的L4数量显著更多。此外，接种疫苗组的雌雄成虫均明显小于对照组。在第二个实验中，在野外条件下进一步评估了该疫苗抗原。小牛按上述方法进行免疫，随后在牧场进行自然感染挑战。接种疫苗动物的柯氏原圆线虫粪便虫卵计数在整个放牧期均有所降低，导致粪便累计虫卵计数显著降低了58.5%。接种疫苗的小牛放牧地块上的感染性柯氏原圆线虫幼虫数量较少，圈舍时牧场幼虫平均计数降低了65%。与对照组相比，接种疫苗组的柯氏原圆线虫总虫数显著降低了81.6%。综上所述，这些数据突出了双结构域活化相关分泌蛋白的保护能力以及通过疫苗接种控制柯氏原圆线虫感染的可能性。
