Resistance Against A Beta Single Bypass The Blood Brain Barrier Into The Mouse Brain Hippocampus Effective Way To Study

Alzheimer’s disease(AD) is a common progressive degenerative disease of the central nervous system.It is histopathologically characterized by beta-amyloid-containing plaques, tau-containing neurofibrillary tangles, reduced synaptic density and neuronal loss in selected brain areas.The accumulation of beta-amyloid (Aβ) peptides in the senile plaques is one of the hallmarks of the progression of AD, and has been considered to be the main cause for neuronal injury and impairment of memory. Both active and passive immunological therapies have been proved successful in animal trials, which can reduce amyloid load and reverse memory deficits in AD mouse model. Thus, antibodies against Aβ may be a potential therapeutic strategy for AD. Anti-Aβmonoclonal antibody studying may provide a hopeful approach for AD therapy.However anti-Aβ monoclonal antibodies need to enter the AD lesions in order to clear Aβ plaques. But the existence of the blood-brain barrier prevents it from the blood circulation into the brain parenchyma.How Macromolecular protein drugs enter into the brain bypass the blood-brain barrier. That is a huge challenge we are facing.Only a few of drugs penetrate into the brain by intravenous, intraperitoneal administration in clinic.Although intraventricular or intracerebral injection can effectively reach into brain, it may cause infection, bleeding and other complications, it is difficult to launch extensively in clinical work.The advantages of nasal administration are less side effects, less dose required, rapidly absorbed and so on.Nasal administration by passive permeation into the brain, the efficiency is very low. And only small subject can be effective.Recent studies found that the CB can be combined with the GM1ligand, which distributed in the nerve cell membraneCB can greatly improved the efficiency after intranasal administration.So we prepare and purify anti-Aβ monoclonal antibody (IgG). Couple IgG with CB (CB-IgG) by sodium metaperiodate method.Analysis the efficiency of the conjugate prepared from the cholera toxin B subunit (CB) and monoclonal antibody against Aβ bypass the blood-brain barrier penetrating the brain hippocampus after intranasal administration.To explore more effective way for the immunotherapy of Alzheimer’s disease (AD). As follows:1. Anti-Abeta mAb preparation,and characterizationFirstly, we prepare mAb, whose subclass is IgGl, with titres of1:1X106. Using Protein A affinity chromatography, the mAb with high purity (>90%) was obtained.2. Couple IgG with CB (CB-IgG) by sodium metaperiodate method.3. Detect the volume and efficiency of monoclonal antibody into the hippocampus of mouse after intranasal administration by Semi-quantitative Western analysis, immunohistochemistry and MRI.CB-IgG group have60%of the IgG into brain,5times higher than the IgG group. Immunohistochemistry showed that most of the monoclonal antibodies into the hippocampus of the brain. And the number of positive cells of the CB-IgG group is three-five times more than the pure IgG group (P<0.05). Magnetic resonance diffusion tensor imaging (DTI) analysis showed that monoclonal antibody can enter the brain in both CB-IgG and IgG groups after nasal administration (P<0.05).CB-IgG group has more obvious impact in brain than IgG group.(P<0.01)CB-IgG can take more anti-Aβ monoclonal antibody into the hippocampus bypass the blood-brain barrier after intranasal administration,5times higher than pure IgG, which provides more effective way for AD immunotherapy.4. Antibodies inAPP mouse brain after nasal administration.Magnetic resonance diffusion tensor imaging (DTI) analysis show significant differences in APP mice and general mouse (P<0.05)Immunohistochemistry showed that the amyloid plaque mainly deposited in the dentate gyrus and entorhinal in the APP brainAntibodies can be found in the dentate gyrus and entorhinal in the APP brain after nasal administration.Conclusion:CB-IgG can take more anti-Aβ monoclonal antibody into the hippocampus bypass the blood-brain barrier after intranasal administration,5times higher than pure IgG, which provides more effective way for AD immunotherapy. Antibodies can be found in the dentate gyrus and entorhinal in the APP brain after nasal administration. This provides a new approach for the study of AD immunotherapy...