Investigation of the involvement of immunity in the spontaneously occurring chronic pancreatitis in male Wisar Bonn/Kobori rats and human.

在本研究的第一部分中，我们旨在评估免疫机制，研究t细胞与腺泡细胞凋亡的关联以及t细胞抑制剂他克莫司对雄性WBN/Kob大鼠慢性胰腺炎发展的预防作用。15周时，由F4/80阳性细胞（=单核细胞/巨噬细胞）、CD4阳性细胞和CD8阳性细胞组成的细胞浸润广泛分布于小叶间结缔组织和实质。特别是CD8阳性细胞侵袭胰腺小叶，与腺泡细胞形成密切联系，部分腺泡细胞表现出凋亡特征。反复皮下注射他克莫司10周完全阻止20周龄时腺泡细胞凋亡、CD4和CD8阳性细胞浸润及胰腺炎的发生。第二项研究的目的是：1)定量测定雌二醇对腺泡细胞凋亡和慢性胰腺炎的影响；2)评估其保护机制。与对照组相比，雌二醇治疗10周显著降低20周龄WBN/Kob大鼠抗单链DNA抗体染色的凋亡腺泡细胞数量、组织学评分和胰腺MPO活性。在20周时，它还显著降低了胰腺羟脯氨酸含量（胶原沉积的指标）的增加。雌二醇引起胰腺中CD4和CD8 T细胞数量的显著减少。雌二醇在体外显著降低1%植物血凝素诱导的BrdU入脾细胞。20周时，胰腺中的雄激素受体无法免疫组织化学鉴定，氟他胺饮食治疗对慢性胰腺炎没有影响。我们还尝试通过静脉注射来自20周龄雄性WBN/Kob大鼠的脾细胞来诱导雄性Wistar大鼠慢性胰腺炎，并利用内窥镜超声技术通过RT-PCR评估从人胰腺活检样本中获得的基因表达。然而，这些试验都以失败告终。总之，我们证明T细胞，可能是CD8阳性细胞，参与诱导腺泡细胞凋亡，并提出他克莫司可能在治疗自身免疫性慢性胰腺炎中找到临床应用的可能性，以及雌二醇剂量依赖性地通过抑制T细胞的浸润和功能来减轻腺泡细胞凋亡和慢性胰腺炎的发展。我们仍在对慢性胰腺炎的发病机制进行研究，在目前的模型中评估新药对慢性胰腺炎和胰腺纤维化的影响。少

In the first part of the present study, we purposed to assess the immunologic mechanism and investigated T-cell association with acinar cell apoptosis and a preventive effect of tacrolimus, a T-cell suppressant, on the development o chronic pancreatitis in male WBN/Kob rats. At 15 week, cellular infiltrates composed of F4/80 positive cells (=monocytes/macrophages), CD4 positive cells, and CD8 positive cells were extensive in the interlobular connective tissue and parenchyma. In particular, CD8 positive cells invaded pancreatic lobules and formed close associations with acinar cells, some of which demonstrated features of apoptosis. Repeated subcutaneous injection of tacrolimus for 10 weeks completely prevented the occurrence of acinar cell apoptosis, infiltration of CD4 and CD8 positive cells, and development of pancreatitis at the age of 20 weeks.The second study was conducted with the aim of : 1) quantitatively determining the influence of estradiol on acinar cell apoptosis and chron … More ic pancreatitis ; and 2) assessing the mechanism of its protection. Treatment with estradiol for 10 weeks significantly decreased the number of apoptotic acinar cells stained with an anti-single strand DNA antibody, histological scores, and pancreatic MPO activity at 20 week old WBN/Kob rats as compared with the control values. It also significantly attenuated the increase in pancreatic hydroxyproline content, an indicator of collagen deposition, at 20 weeks. Estradiol caused significant decrease in the numbers of CD4 and CD8 T cells in the pancreas. Estradiol significantly reduced 1 % phytohemagglutinin-induced incorporation of BrdU into the splenocytes in vitro. Androgen receptors could not be immunohistochemically identified in the pancreas at 20 weeks and dietary treatment with flutamide did not influence the chronic pancreatitis.We also tried to induce chronic pancreatitis in male Wistar rats by intravenously injecting splenocytes derived from 20 week old male WBN/Kob rats and to assess the gene expression by RT-PCR in the biopsy samples obtained from the human pancreas using endoscopic ultrasound technique. However, these trials has resulted in failure.In conclusion, we demonstrated that T cells, possibly CD8 positive cells, are involved in inducing apoptosis of acinar cells and raises the possibility that tacrolimus might find clinical application in the treatment of autoimmune chronic pancreatitis and that estradiol dose-dependently attenuates acinar cell apoptosis and development of chronic pancreatitis by suppressing infiltration and function of T cells. We are still conducting the investigations regarding the pathogenesis of chronic pancreatitis by assessing the effect of new drug on the chronic pancreatitis and pancreatic fibrosis in the present model. Less