Comparative studies on insulin receptors in different age groups in healthy individuals by immunoradiometric techniques

Blood cells have been widely used to evaluate the status of the insulin receptor in man. The receptors exhibited competitive inhibition curves and nonlinear scatchard plots similar to those reported for insulin target tissues, such as the hepatocyte and adipocyte. This study demonstrated specific insulin binding by the erythrocytes [RBCs] of infants, children and adults. The total insulin bound by the RBCs from both children and adults are a small difference over the physiologic range of insulin concentrations. Blood RBCs of infants showed greater number of insulin receptors per cell and significant increase in the total amount of insulin binding than that in either children [P <0.01] or adults [P <0.05] over the physiologic range of insulin concentrations. The affinities of insulin for RBCs of infants, children and adults were similar to each other. It is clear that, the measurement of insulin binding by RBCs may be particularly useful in the study of infants and children with disorders of carbohydrate metabolism to elucidate the role, if any of abnormal receptor function in their conditions

Unexplained infertility: identification by a modified immunoradiometric assay

Several methods have been employed to measure antisperm antibodies with variable sensitivity and specificity in serum and secretion of infertile patients. All of them are not precise means for identification of the presence of antisperm antibodies for patients with unexplained infertility [Gilbert and Haas, 1980]. Therefore, we applied the modified radiolabeled antiglobulin test that has been used successfully to identify and quantitate the antibodies directed towards other human cell surface [Clarke, 1988]. We studied 118 patients in different groups to quantitate the circulating antisperm antibodies using the modified procedure. The obtained data revealed that; the highest and the most significant incidence were found in the patient's secretions [Semen and cervical mucus] with unexplained infertility, and also in the group of males with varicocele. Therefore, It is greatly advisable to use the modified radiolabeled technique as a quantitative assay, and then to help manage infertility in patients with unexplained an mediated infertility