Screening,Expression And Identification Of Aβ OLigomer Specific SingLe Domain Antibody

Alzheimers disease(AD)is a primary degenerative brain disease with persistent advanced neurological dysfunction.This disease usually occurs in the old age of human beings.The pathological changes are mainly characterized by atrophy of the cerebral cortex,accompanied by β-amyloid(Aβ)deposition,neurofibrillary tangles(NFT)and Senile plaque(SP)caused by degeneration,necrosis and reduction of memory neurons.The deposition of β-amyloid in the extracellular space of the cerebral cortex and the cerebral vascular wall is a hallmark of AD neuropathology.At present,there are breakthroughs in the pathogenesis and drug development of AD,especially the imaging diagnosis of Aβ oligomers has become a very effective means of AD treatment.This experiment using the Aβ oligomer-immunized Bactrian camel isolates Peripheral blood lymphocyte.The variable region of heavy chain antibody(VHH)was obtained by RT-PCR,and a primary Aβ single domain antibody library with 1×107 storage capacity was successfully constructed.Then,compatibility of Aβ oligomer was used as antigen to screen the antibody library,and using ELISA to screen positive clone strain that specifically recognizes oligomer.Adding Aβ in Transetta-DE3 Competent cell linked pET-25b-SBP and did soluble expression and protein purification.The results of SDS-PAGE analysis showed that the Aβ antibody was correctly expressed in a soluble form and was successfully purified.The ELISA results indicated that the recombinant expression of Aβ antibody has specific binding activity to Aβ oligomers.Therefore,this experiment successfully constructed the gene antibody library of Aβ bacteriophage antibody by using phage display technology,and obtained specific monoclonal antibody of Aβ oligomer with high specificity and expression,which provides a new way for clinical diagnosis and treatment of Alzheimer’s disease.