De Dios Isabel, Ramudo Laura, Alonso José R, Recio Javier S, Garcia-Montero Andrés C, Manso Manuel A
Department of Physiology and Pharmacology, University of Salamanca, Edificio Departamental, Campus Miguel de Unamuno, 37007 Salamanca, Spain.
FEBS Lett. 2005 Nov 21;579(28):6355-60. doi: 10.1016/j.febslet.2005.10.017. Epub 2005 Oct 24.
CD45 transduces activation signals in inflammatory cells. We investigate CD45 expression on pancreatic acinar cells and examine its role in the inflammatory response which these cells have also shown under certain circumstances. Similar CD45 mRNA levels were found in acinar cells and leukocytes (positive control). Flow cytometric and immunohistochemical analysis showed a heterogeneous CD45 distribution on acinar cells. Activation of acinar cells by incubation with pancreatitis-associated ascitic fluid as evidencied by TNF-alpha production resulted in a decreased CD45 expression, suggesting that CD45 acts as a negative regulator of cytokine production. As a validation of this finding in vivo, a decrease in the acinar CD45 expression in parallel with an increased ability to produce TNF-alpha was found in rats with acute pancreatitis. Our data show that CD45 is constitutively expressed in acinar cells and suggest that it plays an important role in negatively regulating cytokine production.
CD45在炎症细胞中传导激活信号。我们研究了胰腺腺泡细胞上CD45的表达，并探讨了其在这些细胞在某些情况下也会出现的炎症反应中的作用。在腺泡细胞和白细胞（阳性对照）中发现了相似的CD45 mRNA水平。流式细胞术和免疫组织化学分析显示腺泡细胞上CD45分布不均一。与胰腺炎相关腹水共同孵育激活腺泡细胞，表现为肿瘤坏死因子-α（TNF-α）产生，这导致CD45表达降低，提示CD45作为细胞因子产生的负调节因子。作为这一发现的体内验证，在急性胰腺炎大鼠中发现腺泡CD45表达降低，同时产生TNF-α的能力增强。我们的数据表明，CD45在腺泡细胞中组成性表达，并提示其在负向调节细胞因子产生中起重要作用。
