The Production,Characterization Of Monoclonal Antibodies To Oxytocin And The Research On The Roles Of The Antibodies In The 2,4-dinitrofluorobenzene Induced Hypersensitivity In Balb/c Mice

Oxytocin (OT) , a nonapeptide, is mainly synthesized in the supraoptic nucleus (SON) and paraventricular nucleus (PVN) of mamal's hypothalamus, and secreted into blood through neurohypophysis when stimulated to act on the target tissue. The classic physiological roles of OT are the oxytocic and milk-ejecting, besides, OT possesses some other roles like modulating maternal behaviour , pair-bonding and social communication, memory . All the functions mentioned above are induced by the oxytocin receptor (OTR) in the uterus, mammary gland and CNS. Apart from the central nervous system, OT is distributed in the thymus, adrenal gland, ovary, testis etc. Under many kinds of stresses, the OT neurons in CNS are activated and OT is released into peripheral blood and extracellular spaces of neurons. We have found in our lab that, when many kinds of inflammatory cytokines are injected into ventricles of brain, The OT neurons expressed c-fos protein prominently. After long-term immunization with PPD, the plasticity of the OT neurons changed as the more and thicker projections appeared and meanwhile the OT elevated in the hypothalamus and peripheral blood. These all suggested that the OT neurons can be activated by the immune stresses. Many evidences have proved that the OT elevation in the brain after stresses is related to the modulation on Hypothalamus-pitutary-adrenal gland (HPA) axis, but there is still no explanation to the physiological implication of the peripheral elevated OT. The PVN has been known as the modulation centre for the immune response in CNS. When certain immune stress is sensitized and intergrated in the PVN, it can modulate the immune system through either nervous or neuroendocrine way. We think OT may function as a regulating factor from PVN and act on the thymocyte and certain group of peripheral lymphocyte which express OTR. The in vitro thymocytes proliferation test was carried on and showed OT can promote the proliferation of thymocyte slightly. The monoclonal antibodies to OT was successfully produced and we obtained 12 strains of hybridoma, 11 of them secreting specific antibodies to OT and 1 of them secreting antibody that can bind to OT and its analogues. The initial purification and the in vivo neutralization test with the antibodies 2B 11 and 3F1 were done, which showed that 2B1 1 antibody can prolong the pregnant period of Balb/c mice. In 2,4-DNFB induced IV type hypersensitivity in Balb/c mice, the 3F 1 antibody can deteriorate the inflammation which implicates the OT or its analogues are involved in the inhibition of IV type hypersensitivity. In the immunocytochemistry experiment, wee observed that only the 3F1 monoclonal antibody can recoganize the the co-shared epitope by OT and AVP in the thymic epithelial cells and stain the cells.