Objective    To construct human single-chain antibody gene library associated with lung adenocarcinoma

and screen lung adenocarcinoma cell A549-specific antibody.     Methods    The lymphatic tissue near lung adenocarcinoma was used to construct human single-chain antibody gene library. The specific antibody to lung adenocarcinoma cell A549 was screened from the antibody library. Positive clone bacteria were transformed to E. coli HB2151

and their dissolvability was observed. The soluble scFv was purified by affinity chromatography and its relative molecular mass was determined by SDS-PAGE and Western

blotting. The specificity of scFv to human lung adenocarcinoma cells was identified with ELISA.     Results    The phage antibody library of 4.6×10

7

was constructed successfully. Single-chain antibody of human lung adenocarcinoma was enriched. The ratio of yield was increased gradually

181 times higher after 5 rounds of panning than after the first round of panning. SDS-PAGE and Western blotting results showed soluble scFv’ molecular mass was about 30 000. ELISA showed dissolved antibody had high specificity to bind A549 cells

not MDA-MB-435.     Conclusion    The single-chain antibody gene library of human lung adenocarcinoma was constructed successfully

and specific antibodies to lung adenocarcinoma were screened

providing the basis for single-chain antibody radionuclide imaging and treatment.