Biology of Reproduction, Vol 52, 561-571, Copyright © 1995 by Society for the Study of Reproduction

ARTICLES

Purification of heparin-binding epidermal growth factor-like growth factor from pig uterine luminal flushings, and its production by endometrial tissues

GY Kim, GE Besner, CL Steffen, DW McCarthy, MT Downing, MH Luquette, MS Abad and DR Brigstock
Department of Surgery, Ohio State University College of Medicine and Children's Hospital, Columbus 43205, USA.

Pig uterine luminal flushings contain at least four heparin-binding growth factors (HBGF) that stimulate fibroblast [3H]thymidine incorporation. One of these factors, which appeared to be a relatively minor HBGF, was eluted from heparin affinity columns by 1.0 M NaCl and was found to compete with 125I-epidermal growth factor (EGF) for binding to an endometrial carcinoma cell line. This EGF receptor (EGF- R)-binding property was abolished by an antiserum to heparin-binding EGF-like growth factor (HB-EGF) that specifically blocks binding of HB- EGF to the EGF-R. Reverse-phase HPLC resulted in the purification of two EGF-R-binding activities correlated with 13,500 and 17,000 M(r) proteins that reacted with an antiserum raised against residues 9-26 of human HB-EGF. Uterine extracts also contained an EGF-R-binding factor that was eluted from heparin by 1.0 M NaCl and was antagonized by HB- EGF antiserum. Endometrial mRNA subjected to reverse transcriptase- polymerase chain reaction (RT-PCR) and nested PCR through the use of HB- EGF-specific primers yielded fragments of the predicted size. Cloning of the nested PCR product revealed a 380-bp porcine HB-EGF cDNA sequence that was 78-85% homologous to primate or rodent HB-EGF. HB-EGF was immunohistochemically localized primarily to the luminal epithelium in both pregnant and nonpregnant animals.