Rapid radioimmunoassay of circulating chromogranin A: in vitro stability, exploration of the neuroendocrine character of neoplasia, and assessment of the effects of organ failure.

摘要: Chromogranin A is a useful probe of neuroendocrine neoplasia in humans. Here we optimize rapid, sensitive radioimmunoassay modification for detecting chromogranin humans and other species. The site circulation the acellular plasma; platelets contain no immunoreactivity. immunoreactivity plasma stable to repeated freezing thawing, prolonged incubation at 37 degrees C, lyophilization. Venipuncture alone resulted modest (+ 12%, P less than 0.03) increase plasma. Several classic neoplasia-pheochromocytoma, carcinoid tumor, neuroblastoma, (vasoactive intestinal polypeptide)oma-produce markedly increased By contrast, subjects with malignant melanoma, renal cell carcinoma, thymoma all had normal values A. Hypersecretion human choriogonadotropin beta subunit from both (choriocarcinoma) (placenta) syncytiotrophoblast cells was unaccompanied by an A, dissociation compatible lack granular storage release syncytiotrophoblastic peptide hormones. Both hepatic failure plasma, leading concentrations otherwise seen only neoplasia. These observations refine diagnostic specificity