Isolation, purification and characterization of intact and pepsin-derived fragments of laminin from human placenta.

Human laminin, in intact form and as pepsin cleaved fragments, was isolated and purified from placenta. The intact laminin was extracted by 1-M NaCl at neutral pH in the presence of 10-mM EDTA and 3% Triton X-100. This recovered material was purified by DEAE-cellulose and agarose gel chromatography. The laminin fragments P1, P2 and P3 were prepared by limited pepsin proteolysis. Antibodies were prepared against fragment P2. The laminin and its fragments were characterized by amino acid composition, NaDoSO4-polyacrylamide gel electrophoresis and immunochemistry. Results from these studies show that substantial quantities of laminin can be prepared from placenta in this manner.