Single Chain Fv Antibody For HIV-1 Gene Therapy And Its Optimized Production

Single-chain Fv(sFv) are recombinant antibody fragments consisting of only the variable light chain (V_L) and variable heavy chain (V_H) domains covalently connected to one another by a polypeptide linker. Recent advances in antibody engineering have now allowed the genes encoding the sFv, which is probably the minimal structural domain that retains the specific and high-affinity binding properties of the parent antibody , to be stably expressed in precise intracellular locations inside mammalian cells. As a simple and effective new method to replace defective genes or add functional genes to specific cell types, sFv gene therapy is likely to have widespread impact as potential therapeutic agents on both tumor and infectious diseases.HIV-1 is an enveloped retrovirus containing two copies of a single-stranded RNA genome. After binding to a high-affinity receptor on a cell surface, called the CD4 molecule, the virion penetrates the cell and is uncoated by cellular enzymes. Viral reverse transcriptase catalyzes the synthesis of a double-stranded DNA intermediate from the viral RNA. The DNA is transported to the nucleus by the viral proteins and integrated into the host cell's genome by viral integrase(IN) to complete its life cycle. As HIV-1 integrase plays a key role in the early stage of its life cycle, successfully blocking the integrase will halt the HIV-1 replication prior to integration. Based on these, we constructed sFv which binds to the HIV-1 integrase C-terminal domain.