Murdoch M E, Abiose A, Garate T, Hay R J, Jones B R, Maizels R M, Parkhouse R M
Department of Ophthalmology, Ahmadu Bello University Teaching Hospital, Kaduna, Nigeria.
Am J Trop Med Hyg. 1996 Jun;54(6):600-12. doi: 10.4269/ajtmh.1996.54.600.
Antigen (Ag)-specific isotype responses to Onchocerca volvulus Ag (OvAg) were assessed by enzyme-linked immunosorbent assay and immunoblot in 123 residents of a mesoendemic area in northern Nigeria and 16 Nigerians from a nonendemic area. Individuals from an endemic area were divided into six groups on the basis of cutaneous onchocercal pathology: acute papular onchodermatitis (APOD), chronic papular onchodermatitis (CPOD), lichenified onchodermatitis (LOD), atrophy (ATR), depigmentation (DPM) and normal skin, high microfilarial load (NSHMF). Immunoglobulin (Ig)G1-4 levels were all significantly associated with residence in an endemic area after controlling for age and sex (all P values = 0.0001). Both IgG1 and IgG3 were significantly associated with onchocercal clinical category after controlling for age, sex, and microfilarial load (P = 0.0031 and 0.0035, respectively). The IgG1 and IgG3 responses were both highest in LOD and lowest in NSHMF and ATR, respectively. A significant inverse association was found between IgG1 levels and microfilarial load after controlling for age, sex, and clinical category (P = 0.0061). On immunoblotting, 20 (44.4%) of 45 individual onchocerciasis sera contained IgG4 antibodies against a band of 29-31 kD, which was not recognized by pooled sera from individuals with other filarial infections. There was heterogeneity of antigen recognition within each of the onchocercal clinical groups, which together with the small numbers examined by immunoblotting, limits interpretation. Nevertheless, some differences in patterns of antigen recognition were found between the onchocercal groups. The LOD group demonstrated prominent immunoreactivity in IgG1 and IgG3 while a general paucity of low molecular weight reactivity was seen with NSHMF in IgG1-3 subclasses, but there was no specific banding pattern that differentiated NSHMF from those with pathology. Comparison of microfilariae-positive (mf+) and mf- individuals with onchocercal skin disease revealed significantly higher levels of all IgG subclasses and higher overall scores on semiquantitative assessment of immunoblots for IgG1, IgG2, and IgG4 for mf+ individuals. Differing isotypic responses may play a role in the pathogenesis of the clinical spectrum of cutaneous onchocerciasis.
通过酶联免疫吸附测定和免疫印迹法，对尼日利亚北部中度流行地区的123名居民以及16名来自非流行地区的尼日利亚人，评估了针对盘尾丝虫抗原（OvAg）的抗原（Ag）特异性同种型反应。根据皮肤盘尾丝虫病病理学，将来自流行地区的个体分为六组：急性丘疹性皮炎（APOD）、慢性丘疹性皮炎（CPOD）、苔藓化性皮炎（LOD）、萎缩（ATR）、色素脱失（DPM）和正常皮肤、高微丝蚴负荷（NSHMF）。在控制年龄和性别后，免疫球蛋白（Ig）G1 - 4水平均与居住在流行地区显著相关（所有P值 = 0.0001）。在控制年龄、性别和微丝蚴负荷后，IgG1和IgG3均与盘尾丝虫临床类别显著相关（分别为P = 0.0031和0.0035）。IgG1和IgG3反应分别在LOD组中最高，在NSHMF组和ATR组中最低。在控制年龄、性别和临床类别后，发现IgG1水平与微丝蚴负荷之间存在显著的负相关（P = 0.0061）。在免疫印迹中，45份盘尾丝虫病个体血清中有20份（44.4%）含有针对29 - 31 kD条带的IgG4抗体，而其他丝虫感染个体的混合血清未识别该条带。每个盘尾丝虫临床组内存在抗原识别的异质性，这与免疫印迹检测的样本量较少一起限制了解释。然而，在盘尾丝虫病组之间发现了一些抗原识别模式的差异。LOD组在IgG1和IgG3中表现出突出的免疫反应性，而NSHMF组在IgG1 - 3亚类中低分子量反应普遍较少，但没有特定的条带模式将NSHMF与有病理学表现的个体区分开来。对患有盘尾丝虫皮肤病的微丝蚴阳性（mf +）和mf -个体进行比较，发现mf +个体的所有Ig亚类水平显著更高，并且在IgG1、IgG2和IgG4免疫印迹的半定量评估中总体得分更高。不同的同种型反应可能在皮肤盘尾丝虫病临床谱的发病机制中起作用。
