Expression of Pro Form of Prostate-specific Antigen by Mammalian Cells and Its Conversion to Mature, Active Form by Human Kallikrein 2

摘要: To study the expression, biosynthesis, and processing of prostate-specific antigen (PSA) in mammalian cells, recombinant PSA was expressed Syrian hamster tumor cell line AV12-664 (AV12-PSA). Expression monitored by Tandem-MP assay. secreted into medium during logarithmic phase growth at >9 microg/ml stable. The purified from spent AV12-PSA cells did not exhibit any enzymatic activity complex with protease inhibitor, alpha-1-antichymotrypsin. These findings indicated that an inactive form cells. NH2-terminal sequencing confirmed identity to be pro-PSA. This demonstrates is as pro-PSA suggests may present biological fluids. Human kallikrein 2 (hK2), another member hK family, also predominantly prostate epithelium. Although hK2 has been shown trypsin-like activity, little known about its natural substrates. Using proteins, we show can convert mature, enzymatically active PSA, thus establishing a physiological connection between PSA. imply regulating vivo.