Multi-analytic approach to the understanding of the patho-physiology of retinitis pigmentosa and related diseases using genetic, immunologic and clinical imaging methods

为了深入了解视网膜色素变性(RP)的详细病理生理机制，我们对250例典型RP患者进行了遗传学、免疫学和临床影像分析。首先，我们利用转基因公司的WAVE d-HPLC系统建立了省力、省钱的遗传诊断系统。该系统使我们能够筛选29个已报道的RP致病基因，然后进行直接测序，以确认特定基因突变的存在。虽然我们收集了这些患者，而不考虑他们的家庭背景，但在250名接受测试的患者中，我们检测到了30名患者可能的因果基因改变。这一频率与已知基因突变在常染色体显性遗传性RP患者中的频率一样高，被认为是提供最高检测频率的。在我们的研究中，Rho、Rds、Fscn是最常见的候选致病基因，这与日本以前的报道是一致的，表明Prc…我们的基因诊断系统更具正当性。在我们的研究中发现的新的基因改变与疾病的相关性应该进一步评估。然后检测RP患者血清中抗恢复素抗体效价，用ELISA法检测自身视网膜抗原的自身免疫力。在许多RP患者中，与年龄相关性黄斑变性患者相比，抗恢复素抗体效价升高。部分抗体滴度高的患者表现为与视网膜萎缩区不相关的视野丧失，其中一些患者在其病史中曾有过一段时间的疾病快速恶化。提示视网膜变性继发的自身免疫反应可能参与了RP的进展过程。我们还使用光学相干断层扫描(OCT)和视网膜自体荧光来评估RP患者的光感受器状态(即外段丢失)，这被认为是视网膜色素上皮细胞(RPEs)功能良好的标志。有些患者的功能性光感受器和功能性RPE的面积不一致，表明有些患者的光感受器退化和RPE恶化的时间不一致，尽管它们是相伴的复合体。较少

To gain insight into the detailed patho-physiology of retinitis pigmentosa (RP), retinal degenerative disease with rod photoreceptor loss, we studied 250 patients with typical RP using genetic, immunologic and clinical imaging analysis. First of all, we established the labor-and cost efficient genetic diagnostic system using WAVE d-HPLC system (Transgenomic co.). The system enabled us to screen for 29 reported causal genes of RP followed by direct sequencing to confirm the presence of specific gene mutation. Although we collected the patients regardless their familial background, among the 250 patients tested, we detected possible causal gene alteration in 30 patients. This frequency is as high as the frequency of known gene mutation among autosomal dominant RP patients alone which is considered to give the highest detection frequency. In our study, RHO, RDS, FSCN were the most frequent candidates as causal genes, which was compatible with previous reports in Japan, indicating the prac … More ticality of our gene diagnostic system. The relevance of novel gene alterations detected in our study and the disease should be further evaluated. We then tested the serum antibody titer against recoverin in RP patients to check the autoimmunity against self-retinal antigen using ELISA. In many RP patients, anti-recoverin antibody titer was increased compared to that in patients with age-related macular degeneration. Some of the patients with high antibody titer showed visual field loss unproportinal to the retinal atrophy area, and some of these patients had had a period of transient and rapid worsening of the disease in their disease history. These indicated a possible involvement of autoimmune reaction secondary to retinal degeneration in the course of RP progress. We also evaluated the photoreceptor status (i.e. loss of outer segment) in RP patients using optical coherent tomography (OCT) and retinal auto-fluorescence which is considered to indicate the well-functioning retinal pigment epithelial cells (RPEs). The area of functional photoreceptors and that of functional RPEs did not correspond in some patients, indicating that in some patients, there is a discrepancy between the time of photoreceptor degeneration and that of RPE deterioration, although they make a concomitant complex. Less