Montenegro-James S
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana 61801.
Trans R Soc Trop Med Hyg. 1989;83 Suppl:85-94. doi: 10.1016/0035-9203(89)90610-x.
A major breakthrough in babesiosis vaccine research was achieved with the development of methods for continuous propagation in vitro of Babesia parasites. The development of a soluble, exoantigen-containing immunogen, free of erythrocytic antigens, has been proposed as a practical and realistic means of immunoprophylactic control of babesiosis. Such immunogens have been tested for immunogenicity of different strains, minimal protective dose, and protective efficacy of a combined B. bovis-B. bigemina immunogen. During the last 7 years, most of these aspects have been studied in a co-operative research programme between the University of Illinois and the Veterinary Research Institute of Venezuela. The Babesia exoantigen vaccine prevents clinical disease, is effective against different parasite strains, induces protective immunity for at least 13 months, does not immunize against host blood groups, is antigenically stable for at least 3 years at 4 degrees C, and is available in large quantities. Continued improvement of currently available culture-derived immunogens will best guarantee the successful production of food-producing animals in the tropics. Since July 1984, 16 field vaccination trials have been conducted in 7 states of Venezuela in areas where large-scale dairy and beef production is crucial for the livestock industry. These ranches encompassed a cattle production of 14,000, of which 3000 have been vaccinated with a combined B. bovis-B. bigemina immunogen in 2 subcutaneous inoculations with a 4-week interval. In the first 5 trials, a 1-year monitoring period following vaccination and natural tick exposure indicated that the culture-derived vaccine has effectively controlled the clinical manifestation of infection. Studies on antigen characterization are shifting the emphasis from crude antigenic preparations to purified polypeptides, isolated and identified using new biochemical techniques. Current research efforts are directed toward isolation of protective antigens and the production of synthetic vaccines. Until optimal molecular vaccines are developed, a polyvalent inactivated B. bovis-B. bigemina immunogen may offer the best combination of potency, efficacy and safety available for effective immunoprophylaxis against bovine babesiosis.
巴贝斯虫病疫苗研究取得了一项重大突破，即开发出了巴贝斯虫寄生虫体外连续增殖的方法。有人提出，开发一种不含红细胞抗原的可溶性、含外抗原免疫原，是对巴贝斯虫病进行免疫预防控制的切实可行手段。此类免疫原已针对不同菌株的免疫原性、最小保护剂量以及牛巴贝斯虫 - 双芽巴贝斯虫联合免疫原的保护效力进行了测试。在过去7年中，伊利诺伊大学和委内瑞拉兽医研究所的合作研究项目对上述大部分方面进行了研究。巴贝斯虫外抗原疫苗可预防临床疾病，对不同寄生虫菌株有效，诱导的保护性免疫至少持续13个月，不会针对宿主血型产生免疫，在4摄氏度下抗原性至少3年稳定，且产量可观。持续改进目前可得的源自培养物的免疫原，将最有力地保障热带地区食用动物的成功养殖。自1984年7月以来，在委内瑞拉7个州开展了16次现场疫苗接种试验，这些地区的大规模奶牛和肉牛生产对畜牧业至关重要。这些牧场的牛存栏量为14000头，其中3000头已用牛巴贝斯虫 - 双芽巴贝斯虫联合免疫原进行了2次皮下接种，间隔4周。在前5次试验中，接种疫苗并自然接触蜱虫后的1年监测期表明，源自培养物的疫苗有效控制了感染的临床表现。抗原特性研究正从粗制抗原制剂转向使用新生化技术分离和鉴定的纯化多肽。当前的研究工作旨在分离保护性抗原并生产合成疫苗。在开发出最佳分子疫苗之前，多价灭活牛巴贝斯虫 - 双芽巴贝斯虫免疫原可能是有效免疫预防牛巴贝斯虫病的效力、效果和安全性的最佳组合。
