A sandwich enzyme-linked immunoabsorbent assay for measurement of gonadotropin-releasing hormone-toxin conjugates.

Problem: Biological effectiveness of targeted cytotoxins is dependent on their stability, circulating half-life, receptor binding ability, and cytotoxicity. The objective of this study was to compare stability of gonadotropin-releasing hormone (GnRH)-toxin conjugates made with disulfide linkers to those using a maleimidodibutyryl (mb) linkage.

Method Of Study: We developed a sandwich enzyme-linked immunoabsorbent assay recognizing both GnRH analog and cytotoxin to ensure the conjugate measured was intact.

Cytotoxic activity of gonadotropin-releasing hormone (GnRH)-pokeweed antiviral protein conjugates in cell lines expressing GnRH receptors.

Pokeweed antiviral protein (PAP), a 29-kDa ribosome-inactivating protein isolated from the leaves of Phytolacca americana, has potent cytotoxic activity once it enters the cytoplasm of a cell. It is incapable of entering cells by itself. Therefore, our objective was to determine whether a GnRH analog could be used to deliver PAP specifically to cells expressing GnRH receptors.