Chappell C L, Dresden M H, Gryseels B, Deelder A M
Baylor College of Medicine, Houston, Texas.
Am J Trop Med Hyg. 1990 Apr;42(4):335-41. doi: 10.4269/ajtmh.1990.42.335.
Antigens of the Schistosoma mansoni digestive tract are recognized early in the infective process. Two immunogenic components of the excretory/secretory products are proteolytic enzymes that degrade host hemoglobin in the lumen of the parasite gut. These enzymes, CP1 and CP2, belong to the class of cysteine proteinases. In this study, a preparation containing both proteinases has been used to detect proteinase antibodies in the sera of individuals living in Burundi. Of 133 individuals tested, 92% were excreting schistosome eggs. All patients with documented infections had positive anti-proteinase IgG titers (mean = 1:614), while 82% had positive IgM titers (mean = 1:267). Six weeks following praziquantel treatment, patients were assessed for egg excretion and antibody titer. Anti-proteinase IgG titers were significantly lower (mean = 1:259) than pre-treatment titers. Patients who were infected with S. japonicum or S. haematobium typically showed a cross-reactive IgG response. Patients from non-endemic regions yielded negative titers, and those with non-trematode parasites were negative (79%) or weakly positive. S. mansoni cysteine proteinases may be used for the detection of schistosome infections.
曼氏血吸虫消化道抗原在感染过程早期即可被识别。排泄/分泌产物的两种免疫原性成分是蛋白水解酶，它们可在寄生虫肠道腔内降解宿主血红蛋白。这些酶，即CP1和CP2，属于半胱氨酸蛋白酶类。在本研究中，一种包含这两种蛋白酶的制剂已被用于检测布隆迪居民血清中的蛋白酶抗体。在接受检测的133人中，92%的人排出了血吸虫卵。所有有记录的感染者抗蛋白酶IgG滴度均为阳性（平均值 = 1:614），而82%的人IgM滴度为阳性（平均值 = 1:267）。吡喹酮治疗六周后，对患者的虫卵排泄和抗体滴度进行了评估。抗蛋白酶IgG滴度显著低于治疗前滴度（平均值 = 1:259）。感染日本血吸虫或埃及血吸虫的患者通常表现出交叉反应性IgG应答。来自非流行地区的患者滴度为阴性，感染非吸虫类寄生虫的患者滴度为阴性（79%）或弱阳性。曼氏血吸虫半胱氨酸蛋白酶可用于血吸虫感染的检测。
