Expression Of MHC,CD4 And CD8 Molecules In Rat Brain Tissues Of Differential Conditions And Its Significance

Part 1:Expression of MHC,CD4 and CD8 molecules in rat brain tissues of differential ages and its significanceObjective: To investigate the expression of MHC,CD4 and CD8 molecules in rat brain tissues of differential ages and its significance.Methods: The expression of MHC,CD4 and CD8 molecules in rat brain tissues of E15,E19,P0,P7,P14,P28 and aged rat was detected with immunohistochemistry.Results: 1,MHCI molecules was detected in connective tissues,choroid plexus from E19 to aged rat. MHCI molecules also expressed in the neurons of hippocampus and neocortex during the first weeks after born with a trend of stable increase from P0 to P14,P14 at the summit (P<0.05), then that of P28 decreased (P<0.05) and that of the aged hippocampus of rat brain increased again (P<0.05). 2,MHCII,CD4 and CD8 molecules were only detected in connective tissues,choroid plexus without obvious change during all the period (p>0.05) except E15d. 3,MHCI,MHCII,CD4 and CD8 molecules was not observed in cerebellum cortex .Conclution: MHCI molecules expressed in the neurons of hippocampus and neocortex partly during the first weeks after born with a trend of stable increase from P0 to P14, P14 at the summit, it is possibly related with neuronal activity and plasticity of synapses. High MHCI expression of aged rat hippocampus possibly implies it is related with neurological disorders , declination of memory and recognition.Part2:Expression of MHC,CD4 and CD8 molecules in PD rat brain and co-graft of neural stem cells and GDNF for Parkinson disease.Objective :to investigate the occurrence of immunological rejection in PD brain tissue and in co-graft of NSCs and GDNF for PD.Methods:(1)The expression of MHCI,CD4and CD8 molecules in PD rat brain tissues of 7d,14d and 30d was detected with immunohistochemistry .(2)NSCs and GDNF were grafted into the striata of Parkinson's disease model rats. Surviving animals were sacrificed at 2,4and 6w after transplantation,and the brain tissues were stained with immunohistochemistry to inspect the expression of MHCII,CD4 and CD8 molecules.Results: (1)The numbers of MHCI,CD4 and CD8 positive cells in PD rat brain tissue were low at 7d,but increased at 14d and 30d(P<0.05),and 30d at the summit(P<0.05).(2)High MHCII,CD4 and CD8 expression were observed within and around the grafts at 2w after grafting compared with control.These expressions then decreased at 4w (P<0.05) and 6w only few immunopositive cells remained.Conclusions: (1)MHCI,CD4 and CD8 positive cells were found in PD rat brain tissue,it is maybe because that many dopamine neurons were damaged,activated glial cells around expressed MHCI increased,and T cells entered the damaged postions .The...