RESUMEN
Objective To construct and apply a cell line screening Mycobacterium tuberculosis (Mtb)-specific tetramers of CD4+α/β T cell receptor(TCR). Methods The β chains of HLA class Ⅱ (DR) were amplified from tuberculosis patients by PCR. The pMT-HLA-DRB expression vectors that carries the HLA-DR 13 chain and pMT-HLA-DRA-P expression vectors which carries the genes of HLA-DR α chain loaded with Mtb antigen were transfected into S2 cells with the method of calcium phosphate transfection. The expressed Mtb peptide/HLA-DR complexes were primarily identified by the method of cell immunohistochemistry. The cell lines expressing Mtb peptide/HLA-DR complexes were used to screen tetramers of CD4+ TCR by flow cytometry. Results S2 cell lines expressing Mtb peptide/HLA-DR complexes on the cell surface were obtained, two kinds of Mtb specific tetramers of CD4+α/β TCR were screened. Conclusion S2 cell lines expressing Mtb peptide/HLA-DR complexes on the cell surface provide the solid basis of the further research on the TCR tetramers and are helpful for exploring new diagnostic study methods about tuberculosis and developing new vaccines.