Natori Y, Hayakawa I, Shibata S
Clinical Research Institute, National Medical Centre, Tokyo, Japan.
Clin Exp Immunol. 1987 Nov;70(2):434-9.
Our previous paper showed that the glycoprotein of Mr 108,000 (gp108) is one of the major components of rat renal tubular brush border antigens and that an injection of anti-gp108 antiserum in rats induces passive Heymann nephritis with acute and severe proteinuria. In this study, gp108 was identified as a monomer of dipeptidyl peptidase IV (DPP IV). The anti-gp108 antibody was shown to immunoprecipitate DPP IV from Triton-extract of renal tubular membrane fractions. DPP IV was co-purified with gp108 from the Triton-extract by columns of DEAE-cellulose and Bio-gel A-1.5 m. The ratio of DPP IV activity and gp108 content was nearly constant throughout the purification steps. The final purified gp108 showed a high specific activity of DPP IV, comparable to that reported for purified rat DPP IV. These results indicate that gp108 is a monomer of DPP IV.
我们之前的论文表明，分子量为108,000的糖蛋白（gp108）是大鼠肾小管刷状缘抗原的主要成分之一，并且给大鼠注射抗gp108抗血清会诱发伴有急性严重蛋白尿的被动型海曼肾炎。在本研究中，gp108被鉴定为二肽基肽酶IV（DPP IV）的单体。抗gp108抗体可从肾小管膜组分的Triton提取物中免疫沉淀DPP IV。通过DEAE-纤维素柱和Bio-gel A-1.5m柱，DPP IV与gp108从Triton提取物中共同纯化。在整个纯化步骤中，DPP IV活性与gp108含量的比率几乎恒定。最终纯化的gp108显示出较高的DPP IV比活性，与报道的纯化大鼠DPP IV相当。这些结果表明gp108是DPP IV的单体。
