Systemic release of mucosal mast-cell protease in primed rats challenged with Nippostrongylus brasiliensis.
Systemic release of mucosal mast-cell protease in primed rats challenged with Nippostrongylus brasiliensis.
复制标题
在用巴西圆线虫攻击的致敏大鼠中粘膜肥大细胞蛋白酶的全身释放。
作者：
H. Miller;R. Woodbury;J. Huntley;G. Newlands
用灵敏的酶联免疫吸附试验(ELISA法)测定了幼鼠和经巴西线虫攻击的大鼠血清中的丝氨酸蛋白酶--大鼠肥大细胞蛋白水解酶II(RMCPII)的分泌。RMCPII在刺激大鼠体内的分泌具有时间和剂量依赖性(1-3微克RMCPII/ml血清，攻击后1小时)。用5日龄的蠕虫十二指肠内攻击幼鼠后，RMCPII的全身释放较慢且不明显。新生大鼠血清中未检测到RMCPII。可溶性虫抗原对幼龄大鼠无影响，经十二指肠和静脉注射后1小时，血清RMCPII水平分别为10.5微克/毫升和122微克/毫升。线虫攻击后MMC形态变化不大，空肠RMCPII含量无明显变化。静脉注射蠕虫抗原后，MMC数量显著减少，其余细胞呈空泡化和淡染，但未观察到颗粒吐出。空肠中RMCPII的含量也明显减少。这些结果明确地表明，MMC被激活是对巴西新月形虫攻击感染或寄生虫抗原的反应。此外，检测实验动物血清中分泌的RMCPII的能力为确定MMC参与粘膜表面的病理反应提供了一种高度敏感和唯一选择性的分析方法。
The systemic secretion of a serine protease, rat mast-cell protease II (RMCPII), a major product of rat mucosal mast cells (MMC), was measured by a sensitive enzyme-linked immunosorbent assay (ELISA) in the sera of naive and primed rats challenged with the nematode N. brasiliensis. The systemic secretion of RMCPII was both time- and dose-dependent in primed rats (1-3 micrograms RMCPII/ml serum, 1 hr after challenge). Systemic release of RMCPII was slower and less pronounced in naive rats following intraduodenal challenge with 5-day-old worms. No RMCPII was detected in the sera of naive rats challenged with 4-day-old N. brasiliensis. Soluble worm antigen had no effect in naive rats, but when it was given intraduodenally or intravenously to primed rats, the serum levels of RMCPII 1 hr later were 10.5 micrograms/ml and 122 micrograms/ml, respectively. Few morphological changes were detected in MMC following worm challenge and the jejunal content of RMCPII was unaltered. A substantial reduction in the number of MMC occurred following intravenous injection of worm antigen, and the remaining cells were vacuolated and pale-staining, although granule exocytosis was not observed. Significant reduction in the jejunal content of RMCPII was also evident. These results demonstrate, unequivocally, that MMC are activated in response to N. brasiliensis challenge infection or to parasite antigens. In addition, the ability to detect secreted RMCPII in the sera of test animals provides a highly sensitive and uniquely selective assay to determine the participation of MMC in pathological reactions at mucosal surfaces.