engleski

Isolation of placental protein with immunological and receptor activities similar to growth hormone

It is well known that human placenta synthesizes and secretes into maternal circulation polypeptide hormones. Two hormones which have established clinical use are placental lactogen (hPL) and chorionic gonadotropin (hCG). Recently, it has been discovered that human placenta also synthesizes and secretes a variant form of human growth hormone (hGH-N), now called hGH-V protein. The aim of this work was to isolate hGH-V hormone from human term placenta. The purification steps were monitored by measuring hGH as well as hPL and hCG immunoactivities. hGH immunoactivities were separatedfrom hPL and hCG immunoactivities by three simple chromatographic steps. By ion-exchange chromatographies (anion- and subsequent cation-exchange chromatography) hPL immunoactivities were separated from hGH immunoactivities. The contaminating, hCG immunoactivity was separated from hGH immunoactivity by size-exclusion chromatography. When compared with the crude placenta homogenate, the isolated protein (hGH-V) was purified 648-fold with an overall recovery of 0.06%. The isolated protein, Mr 22, 000, possessed immunological as well as receptor activities similar to human growth hormone (hGH-N), isolated from human pituitary.

placenta; groth hormone; placental growth hormone

Rad je financiran projektom 3-01-211 ministarstva znanosti i tehnologije RH