A Study About Benefit And Harmfulness Of Antibrain-antiody In Brain's Immune

Objective:To study the immune attacking of Antibrain-antibody(AB-Ab) which was injected into the cortex of rabbits; To observe the effect of AB-Ab on cell proliferation,apoptosis and invasive ability of C6 glioma in vitro; To explore the specific performance and mechanism of immunosuppression therapy on secondary brain injury of rabbits in imaging, pathology and CSF testing.Method:The experiment was divided into three parts, the first part,24 New Zealand white rabbits were randomly divided into three groups, namely, ABAb group(n=8),immunosuppression therapy group(n=8),NS group(n=8). The rabbits of ABAb group and immunosuppression therapy group were injected with AB-Ab into cortex,meanwhile the rabbits of NS group were injected with NS into cortex. Expression of Glu were examined by means of immunohistochemistry in the cerebral cortex of rabbits,apoptosis of the neurons was determined with TUNEL staining; the second part, C6 glioma cells were divided into experimental groups and control group. Different concentrations of AB-Ab were administrated to the experimental groups but the control group. Respectively MTT, flow cytometry and Boyden chamber measured the proliferation inhibition rate,apoptosis rate and the transmembrane cell numbers of C6 cells;the third part,24 New Zealand white rabbits were randomly divided into three groups, namely, sham-operated group(n=8), trauma group(n=8), immunosuppression therapy group (n=8 cyclosporine A 10mg/kg injected through ear fringe vein at different time points, namely,1 hour before operation 1 day,2 days,3 days after operation). The rabbit brain trauma models of lateral fluid percussion were established in trauma group and immunosuppression group, and the rabbits of sham-operated group were operated only by opening bone windows without blow. 8hours,3 days,7 days,14 days after operation the three groups were sent to detect brain edema by MRI; 15 days after injury, all the rabbits were killed, brain tissues of the operation side were extracted for pathological examination; Cerebrospinal fluid of all the rabbits were respectively phlebotomized from cerebellomedullary cistern at different time points, namely,1 hour before operation,1 day,3 days,7 days,14 days after operation, and the ELISA method was used to detect concentration of AB-Ab. Results:the first part,1 month after the AB-Ab injection, comparing to NS group and immunosuppression therapy group,neuronal apoptosis and Expression of Glu in cortex significantly increased in ABAb groups. There was statistically significant difference between AB-Ab and NS group and immunosuppression therapy group (P<0.05); the second part,AB-Ab decreased the cell proliferation,induced the cell apoptosis and inhibited the invasive ability of C6 glioma cells markedly in vitro in a dose-depended manner(P<0.05); the third part, MRI of immunosuppression group showed their edema volume compared with trauma group at the same time point significantly reduced and its swelling period significantly shorter; pathological brain slices of immunosuppression group displayed that the number of inflammatory cells was significantly decreased compared with trauma group and control group; the concentrations of antibrain-antibody in CSF of immunosuppression group compared with trauma group and control group were significant lower at the same time points. There was statistically significant difference between the three groups. The pairwise comparisons of Three groups in imaging, pathology and body fluids testing were significantly different (P<0.05).Conclusions:1.The autoimmune attacking of ABAb induced neuron apoptosis and increasment of Glu expression,and led to brain injury;2.AB-Ab can inhibit proliferation invasive ability and induce apoptosis of C6 glioma cells; 3.AB-Ab is a double-edged sword,one hand it can kill tumor cells in brain,on the other hand it is also harmful to normal nerve cells;4. The concentration of ABAb in CSF signicantly increased after brain trauma, so we think brain trauma could result in autoimmune diseases. The autoimmune reaction is maybe a cause of the secondary brain injury;5.Immunosuppression therapy can alleviate immune reaction and inhibit production of AB-Ab,protect brain from the secondary brain injury; 6. We considered, immunosuppression therapy will become a new therapy react on brain trauma.