Pathogenetic roles of human endogenous retroviruses in autoimmune diseases

为了研究人类内源性逆转录病毒（HERV）在自身免疫性疾病中的致病作用，我们培育了携带HERV基因组的转基因大鼠，并对转基因大鼠作为模型进行了分析。并尝试克隆血管内皮细胞作为自身免疫性疾病和类风湿关节炎滑膜组织靶点的新型herv的cDNA基因。本研究项目的结果如下：1。建立了两条携带HERV- r全长基因组的转基因鼠系，这是一种单拷贝型HERV，在几种人体组织中表达env基因。该基因在大鼠哈德氏唾液腺和下颌下唾液腺中高水平特异性表达。利用兔抗herv - r合成多肽抗血清，在哈德氏腺腺泡细胞中检测到85kDa的Env糖蛋白，含有约23kDa的多糖。该基因从妊娠第12天开始在母体中持续表达，并在妊娠第18天的胎儿中检测到。通过转基因大鼠和非转基因大鼠的皮肤移植实验，转基因大鼠在非转基因大鼠中的移植物被宿主大鼠的免疫反应排斥，提示85kDa Env糖蛋白被非转基因大鼠识别为免疫靶点。虽然在转基因大鼠中没有自发发生疾病，但当大鼠对85kDa Env糖蛋白的免疫耐受被破坏时，可能会发生herv -r相关的免疫紊乱。我们筛选了类风湿关节炎患者胎盘、脐静脉内皮细胞和滑膜组织的cDNA文库，使用dna相关的人逆转录病毒序列混合物作为探针。我们检测到几个带有逆转录病毒序列的克隆，但尚未发现新的HERV序列。然而，我们证实了一种在正常组织中未检测到任何转录的HERV在几个没有疾病的胎盘中表达。

To investigate the pathogenetic roles of human endogenous retroviruses (HERVs) in autoimmune diseases, we produced transgenicrats carrying an HERV genome and analyzed the transgenic rat as a model. And we tried the cDNA gene cloning for novel HERVs from vascular endothelial cells as a target of autoimmune diseases and synovial tissues of rheumatoid arthritis. Results of this research project were described below.1. Two lines of transgenicrats carrying the full-length genome of HERV-R, which is a single copy type of HERV and expresses the env gene in several human tissues, were established. The transgene was specifically expressed at high levels in Harderian and submandibular salivary glands of the rats. Using a rabbit anti-HERV-R synthetic peptides antiserum, 85kDa of Env glycoprotein, contain about 23kDa of glycan, was detected in acinar cells of the Harderian glands. The transgene was consistently expressed in concepti from day 12 after gestation and was detected in fetuses at day 18 of gestation. By the skin transplantation experiment between the transgenic and non-transgenic rats, grafts of transgenic rats in non-transgenic rats were rejected by immunological reaction of host rats, suggesting that the 85kDa Env glycoprotein is recognized as an immunological target by non-transgenic rats. Although no disease was spontaneously developed in the transgenic rats, HERV-R-related immunological disorders may develop in the rats when the immunological tolerance against the 85kDa Env glycoprotein is broken.2. We screened cDNA libraries of human placentas, umbilical vein endothelial cells and synovial tissues of rheumatoid arthritis patients, using mixture of DNAs-related human retrovirus sequences as probes. Several clones with retrovirus sequences were detected, but we found no novel HERV sequence, yet. However, we evidenced that one HERV, which is not detected any transcription in normal tissues in previous reports, is expressed in several placentas without diseases.