Singh G, Katyal S L, Wong-Chong M L
Pediatr Res. 1986 Aug;20(8):802-5. doi: 10.1203/00006450-198608000-00021.
Rat lung lavage contains a 10 kDa protein that has been shown by immunocytochemistry to be specific for Clara cells. An inhibition enzyme-linked immunosorbent assay was established for this protein using rabbit antibody to the 10 kDa Clara cell protein. The assay has a sensitivity of about 3.0 ng/ml and a working range of about 5 to 50 ng/ml. Quantitation of the 10 kDa protein in amniotic fluid revealed an increase of about 4-fold at day 20 of gestation. The 10 kDa protein content of lung homogenate increased steadily from day 18 of gestation to 1 wk after birth, after which a decline was observed. Nearly 60-fold increase in the concentration of the 10 kDa Clara cell protein in lungs was noted from day 18 of gestation to birth and a further about 7-fold increase was noted from the day of birth to 1 wk of age. A progressive increase in the 10 kDa protein, with increasing age, was also noted on immunoblot analysis of lung homogenates. As judged from the immunoblots of lung homogenates, stained with rabbit antirat 10 kDa protein antiserum, the content of an antigenically similar 200 kDa Clara cell protein was negligible. The quantitative results for 10 kDa Clara cell protein parallel the results of immunocytochemistry and quantitation of the volume density of Clara cell granules indicating that quantitation for the 10 kDa protein could be used to monitor the development of Clara cells and that of the pulmonary airways.
大鼠肺灌洗液中含有一种10 kDa的蛋白质，免疫细胞化学显示该蛋白质对克拉拉细胞具有特异性。利用兔抗10 kDa克拉拉细胞蛋白抗体建立了针对该蛋白质的抑制酶联免疫吸附测定法。该测定法的灵敏度约为3.0 ng/ml，工作范围约为5至50 ng/ml。羊水10 kDa蛋白质的定量分析显示，在妊娠第20天时增加了约4倍。肺匀浆中10 kDa蛋白质的含量从妊娠第18天到出生后1周稳步增加，之后出现下降。从妊娠第18天到出生，肺中10 kDa克拉拉细胞蛋白的浓度增加了近60倍，从出生到1周龄又增加了约7倍。在对肺匀浆进行免疫印迹分析时，也注意到随着年龄的增长，10 kDa蛋白质逐渐增加。根据用兔抗大鼠10 kDa蛋白质抗血清染色的肺匀浆免疫印迹判断，抗原性相似的200 kDa克拉拉细胞蛋白的含量可以忽略不计。10 kDa克拉拉细胞蛋白的定量结果与免疫细胞化学结果以及克拉拉细胞颗粒体积密度的定量结果平行，表明10 kDa蛋白质的定量可用于监测克拉拉细胞和肺气道的发育。
