engleski

Isolation of Placental Protein with Immunological and Receptor Activities Similar to Growth Hormone

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

human placenta ; human growth hormone ; placental growth hormone ; placental lactogen ; chorionic gonadotropin

Rad je izrađen u KB "Sestre milosrdnice" i financiran od Ministarstva znanosti i tehnologije RH - projekt 3-01-211.