Proudman C J, Holmes M A, Sheoran A S, Edwards S E, Trees A J
Liverpool School of Tropical Medicine/Faculty of Veterinary Science.
Parasitology. 1997 Jan;114 ( Pt 1):89-94. doi: 10.1017/s0031182096008086.
The equine intestinal cestode Anoplocephala perfoliata has been the subject of recent epidemiological and immunological studies because of its suspected association with intestinal disease in the horse. We have previously shown that the IgG(T) subtype antibody response to the 12/13 kDa component of the parasite excretory/secretory (E/S) antigen is positively correlated with parasite intensity. In this study, we utilize that correlation to examine the changes in natural infection intensity with age. Infection intensity based on IgG(T) responses showed a triphasic age-dependency pattern with peak mean worm burden in the 6 months-2 years age group, falling to a lower plateau level from 3 to 15 years, and rising again in older age groups. Anti-E/S total IgG was found to have a convex age-dependency curve, with maximal response in the 6 months-2 years old age group. IgG(a) showed a triphasic response similar to the age-intensity profile of IgG(T); IgG(c) showed steadily increasing levels of antibody with age. The IgG(b) age-dependency profile was intermediate between IgG(a) and IgG(c). Age-specific correlation coefficients between anti-12/13 kDa IgG(T) (as a measure of infection intensity) and IgG(a) and IgG(b) revealed statistically significant values for many age groups. The relative importance of exposure to infection and the development of acquired immunity as determinants of the observed age-intensity pattern is considered.
马肠道绦虫叶状裸头绦虫由于被怀疑与马的肠道疾病有关，已成为近期流行病学和免疫学研究的对象。我们之前已经表明，对该寄生虫排泄/分泌（E/S）抗原12/13 kDa成分的IgG(T)亚型抗体反应与寄生虫感染强度呈正相关。在本研究中，我们利用这种相关性来研究自然感染强度随年龄的变化。基于IgG(T)反应的感染强度呈现出三相年龄依赖性模式，6个月至2岁年龄组的平均虫负荷峰值最高，3至15岁时降至较低的平稳水平，而在老年组中又再次上升。发现抗E/S总IgG具有凸形年龄依赖性曲线，在6个月至2岁年龄组中反应最大。IgG(a)呈现出与IgG(T)的年龄-强度分布相似的三相反应；IgG(c)显示抗体水平随年龄稳步增加。IgG(b)的年龄依赖性分布介于IgG(a)和IgG(c)之间。抗12/13 kDa IgG(T)（作为感染强度的指标）与IgG(a)和IgG(b)之间的年龄特异性相关系数在许多年龄组中显示出统计学上的显著值。我们考虑了暴露于感染和获得性免疫发展作为观察到的年龄-强度模式决定因素的相对重要性。
