[Activation of specific T lymphocyte induced by artificial antigen presenting cell complex in vitro]

This study was aimed to investigate the effect of artificial antigen-presenting cells (aAPCs) on inducing activation and proliferation of specific T-lymphocytes through stimulating biological function of dendritic cells with aAPCs in vitro. The specific antigen of chronic myeloid leukemia CML-28 was screened as objective antigen peptide by using magnetic microbeads as vector; the CML-28 epitope sequence (Vltfaldsv) was obtained by antigen epitope prediction software; this epitope was coupled with MHC molecule and used as first signal molecule, the B7-1 molecule was used as second signal molecule; these 2 molecules simultaneously were loaded onto surface of magnetic microbeads so as to contract aAPC complex. The bone marrow mononuclear cells were derived from HLA-A2(+) healthy bone marrow donors, CD8(+) T lymphocytes were screened and co-cultured with aAPC complex. During culture the 5, 6-carboxyfluorescein diacetate succinimidyl ester (CFSE) was added and proliferation of T-lymphocytes was detected by CPSE and proliferation level of specific T lymphocytes was detected by flow cytometry. The results showed that the proliferation level of CML-28 specific T lymphocytes obviously increased in experimental group, average level was 17.34 +/- 0.65%, while average level in control was 2.25 +/- 0.43%, there was significant difference between them (p < 0.01). It is concluded that the aAPC complex can mimic human APCs in vitro, and stimulate activation and proliferation of CD8(+) specific T lymphocytes.