Subunit structure of calgranulins A and B obtained from sputum, plasma, granulocytes and cultured epithelial cells

The calcium-binding proteins calgranulins A and B co-purified with an clastase-specific inhibitor after the affinity and cation-exchange chromatography of the perchloric acid-soluble fraction of pooled sputum collected from patients with chronic obstructive pulmonary disease (Sallenave, J.-M. and Ryle, A.P. (1991) Biol. Chem. Hoppe-Seyler 372, 13–21). The calgranulins were separated from the inhibitor by reverse-phase FPLC. Protein blot analysis of the calgranulin fraction in the absence of reducing agent revealed a band of 25 kDa corresponding to the disulphide-bonded heterodimerization of the two monomer components. Similar results were obtained from the immunoprecipitation and protein blot analysis of plasma, granulocytes and cultured epithelial cells. This implies that the calgranulins exist in the heterodimeric form in secretions in vivo. Their association with pancreatic elastase during the affinity chromatography stage of purification implicates them in the tissue destruction elicited by the inflammatory response in chronic obstructive pulmonary diseases.

在对从慢性阻塞性肺疾病患者收集的混合痰液的高氯酸可溶性部分进行亲和层析和阳离子交换层析后，钙结合蛋白钙防卫蛋白A和B与一种弹性蛋白酶特异性抑制剂共同纯化（Sallenave，J. -M.和Ryle，A.P.（1991年）《生物化学杂志》（Biol. Chem. Hoppe - Seyler）372卷，13 - 21页）。通过反相快速蛋白质液相色谱（FPLC）将钙防卫蛋白与抑制剂分离。在无还原剂的情况下对钙防卫蛋白组分进行蛋白质印迹分析，显示出一条25 kDa的条带，对应于两种单体成分的二硫键连接的异二聚体化。对血浆、粒细胞和培养的上皮细胞进行免疫沉淀和蛋白质印迹分析也得到了类似的结果。这意味着钙防卫蛋白在体内分泌物中以异二聚体形式存在。它们在纯化的亲和层析阶段与胰弹性蛋白酶的结合表明它们参与了慢性阻塞性肺疾病中炎症反应引发的组织破坏。