GENETIC REMODELING OF GANGLIOSIDES RESULTED IN THE ENHANCED REACTIONSTO THE FOREIGN SUBSTANCES IN SKIN

Several lines of transgenic mice with gangliosides GM2/GD2 synthase ge ne were established, and the expression levels of the transgene in bra in, liver, spleen and thymus were analyzed by comparing with those in their litter mates. Among four tissues, brain and skin showed markedly high expression levels of the transgene in Northern blotting, Particu larly, transgenic mice skin showed about 10-fold higher expression of GM2/GD2 synthase gene than the wild type mice skin, Therefore, alterat ions in the morphology, glycolipid components, and responses to the ex ogenous stimulations in the transgenic mice skin were examined, Gangli osides in the transgenic skin were dramatically converted from GM3 to GM1, whereas no morphological changes were observed, However, when ski n flap test was performed with insertion of nylon membranes under the skin flaps, much stronger inflammatory reactions consisting of edema, marked thickness, and cell infiltration were observed in the transgeni c mice compared with the wild type, Similar enhanced inflammatory reac tion was also observed in the skin injected by silicon gel, and in the peritoneal reaction to the injected casein, Main cell population in t hese inflammatory reactions consisted of neutrophils, suggesting an in creased sensitivity of neutrophils to chemotactic factors in the trans genic mice.