Development of novel therapy for immune-mediated hematological diseases targeted for phagocytosis and complement regulatory protein

我们的研究结果总结如下：克隆了免疫介导性溶血性贫血(IMHA)中最已知的自身抗原带3和血糖蛋白的cDNA，并研究了其与犬疾病的关系。我们还克隆了犬CD47分子的cDNA，并检测了其在IMHA犬红细胞和白细胞上的表达。CD47在健康犬的红细胞和淋巴细胞上均有表达，在再生的红细胞中其表达水平升高。这些结果表明，高表达CD47分子的再生红细胞可能具有抗噬血细胞的作用。此外，犬红细胞上CD47的表达水平随着红细胞的保存而逐渐降低，提示CD47的表达可能与红细胞保存疾病有关。P-糖蛋白(P-gp)是一种被认为是化疗耐药的膜蛋白。P-gp与细胞裂解的关系也有报道。我们对犬P-gp和编码P-gp蛋白的mdr1基因进行了几项基础研究。我们通过实验将mdr1基因导入犬细胞，并证实了其表达水平和功能。此外，我们还检测了柯利犬细胞上P-gp的表达水平。我们还对犬IMHA和IMTP的临床病例进行了临床病理研究，以了解预后因素并建立评分系统。在项目期限(2006-2007)期间，我们无法为狗和猫的免疫介导的血液病开发新的治疗方法。然而，该项目获得的结果包含有价值的信息，这些信息可能有助于理解狗和猫的免疫介导的血液病。

The summary of our research results are as follows:We cloned cDNA of Band 3 and glycophorin, which are the most known self antigen in immune-mediated hemolytic anemia (IMHA), and examine its relationship with canine diseases. We also cloned cDNA of canine CD47 molecule, which considered as inhibitor for hemophagocytosis, and examine its expression on red and white blood cells of dogs with IMHA. CD47 was expressed on RBC and lymphocytes in healthy dogs and its expression level was increased in regenerated RBC. These results indicated that regenerated RBC with high amount of CD47 molecules may resistant to hemophagocytosis. Furthermore, the expression level of CD47 on canine RBC was gradually decreased by RBC storage, indicating that the CD47 expression may related with RBC storage diseases.P-glycoprotein (P-gP) is a membrane protein which considered as chemoresistance. P-gP also was reported its relationship to cell lysis. We investigated several basic research on canine P-gP and mdr1 gene which codes P-gP protein. We experimentally introduce mdr1 gene into canine cells and confirm its expression level and function. Furthermore, we examine the expression level of P-gP on cells of Collie dog.We also performed clinicopathological study on clinical cases of canine IMHA and IMTP to know the prognostic factors and to develop scoring system.We can not develop novel therapy for immune-mediated hematological diseased of dogs and cats during the project term (2006-2007). However, the results obtained in the project contain valuable information which might be useful for understanding of immune-mediated hematological diseases of dogs and cats.