Preparation and partial characterization of monoclonal antibodies specific for the nascent non-triple helical form of the type IV collagen alpha 1 chain

•New antibodies recognize non-triple helical form of the type IV collagen α1 chain.•The antibodies react with the nascent polypeptide secreted from human cells.•The antibodies recognize different epitopes on the non-triple helical polypeptide.

This report describes the preparation and partial characterization of monoclonal antibodies that are reactive specifically with the nascently produced non-triple helical form of the type IV collagen α1 chain, designated as NTH α1(IV). These antibodies were nonreactive with the α1 chain of the type IV collagen in the triple-helical conformation. Three antibodies, #141, #179 and #370, with different epitopes in NTH α1(IV) were found to be reactive with the nascent polypeptide secreted from human normal cells and a human carcinoma cell line. The antibodies with different epitopes may provide a key method for elucidating the physiological function and tissue distribution of NTH α1(IV), which is distinct from the chain derived from triple-helical type IV collagen.