NOVEL ANTIGENS FOR THE SERODIAGNOSIS OF HUMAN BABESIOSIS

加强对蜱传感染的监测表明，许多感染莱姆病的人同时感染了微小巴贝虫（人类巴贝虫病的病原体）和埃利希体，这两种病毒对免疫功能低下的人都可能致命，并已证明会影响输血。由于微螺旋体感染（疟疾样红细胞内寄生虫）的治疗与莱姆病有很大的不同，因此需要一种准确的血清学检测来区分这两种感染。拟议的研究将能够开发一种酶联免疫吸附试验和结合使用微芽孢杆菌重组的免疫印迹试验，这将补充目前可用的莱姆病试验，并最终促进对献血者的试验。这种测试的发展提高了我们鉴别诊断蜱传疾病的能力，并促进了适当治疗的实施。在鉴定免疫优势重组抗原方面，Corixa已经取得了进展。这一点，再加上与蜱传疾病领域的主要研究人员、血库和莱姆病检测的主要参考实验室的合作，以及利用其广泛的血清库，应该能够实现本提案的目标。拟议的商业应用拟议的研究将导致用于血库和参考实验室的诊断测试的商业化。在存在其他蜱传感染（如莱姆病和人粒细胞性埃利希体病）的情况下，这种检测将改进对巴贝斯虫病的鉴别诊断。在美国和世界范围内，这种测试的估计市场应该与莱姆病测试相似。目前这个市场的规模估计为每年3000万至5000万美元，但如果血库检测甚至在区域基础上被强制执行，这个市场的规模可能会更大。

Increase surveillance of tick-borne infections has shown that many individuals infected with Lyme disease have co-infections with Babesia microti (agent of human babesiosis) and Ehrlichia, both of which are potentially fatal in immunocompromised individuals and have been shown to impact blood transfusions. Since the treatment of B. microti infections (malaria-like intraerythrocytic parasite) is vastly different that Lyme disease there is a need for an accurate serology test to differentiate the two infections. The proposed studies will enable the development of an ELISA and Immunoblot test using B. microti recombinants in combination that will supplement the currently available Lyme disease test and eventually facilitate testing of blood donors. Development of such tests improves our ability to differentially diagnose tick-borne diseases and facilitates administration of the appropriate treatment. Advances have already been achieved at Corixa in identifying immunodominant recombinant antigens. This, in combination with collaborations with key investigators in the area of tick-borne diseases, blood banking and a leading reference laboratory for Lyme disease testing and access to their extensive serum bank should enable the goals and objectives of this proposal to be achieved. PROPOSED COMMERCIAL APPLICATION The proposed studies will lead to commercialization of diagnostic tests for use in the blood bank and reference laboratory. Such tests would provide for improved differential diagnosis of babesiosis in the presence of other tick-borne infections e.g. Lyme disease and Human Granulocytic Ehrlichiosis. The estimated market for such a test should be similar to that for Lyme disease testing both in the U.S. and worldwide. Current estimates for this market are 30-50 million dollars/year but could be greater if blood bank testing is mandated even on a regional basis.