Detection of multiple PRL- and GH-like proteins in human pituitary by Western blot analysis.

Surgically removed normal and tumorous pituitary tissues from a prolactinoma patient were analyzed by Western blot techniques for PRL and GH variants. Criteria for identification were the Rf of the bands within the gel, immunologic crossreactivity to specific antisera, and structural verification by tyrosine peptide-mapping of individual bands from the gel. The authors found the tumor-tissue to be characterized by the presence of a PRL band greater in concentration than in the normal tissue and the virtual absence of a GH band.

Demonstration of 20K growth hormone in human plasma by gel electrophoretic-immunostaining-autoradiographic assay (GEISAA).

A variant of human growth hormone (hGH), in which 15 amino acids are missing (commonly referred to as 20K-hGH in contrast to the traditional form which is referred to as 22K-hGH), is known to exist in human pituitary glands. However, lack of a method to measure it in blood has hindered investigations of its physiopathology. We have applied a newly-developed technique called GEISAA for its detection in small volumes of human plasma.

Glycosylated human prolactin.

A glycosylated form of human PRL (G-hPRL) was isolated from pituitary glands. The glycoprotein was separated from the major form of PRL on columns of lentil lectin-Sepharose 4B. The major form of PRL did not bind to the lentil lectin, whereas the glycosylated modification did and could be eluted with methyl-alpha-D-mannopyranoside.

Antigenic sites of human growth hormone and related molecules detected by monoclonal antibodies to human growth hormone.

Four major antigenic sites for human growth hormone (hGH) were identified by 27 mouse monoclonal antibodies to hGH. Sites 1 and 2 are spatially close whereas sites 3 and 4 are located in other parts of the molecule. There also appears to be a subdivision of antigenic sites.