[Activating effects of protein transduction domain mediated BCR/ABL protein on CML T cells]

To study the activating effect of protein transduction domain (PTD) mediated BCR/ABL protein on T cells from CML patients.

The plasmid containing PTD and b3a2 bcr/abl of CML was constructed by genetic engineering and expressed in E. coli. The peripheral blood mononuclear cells from CML patients were stimulated in vitro with purified PTD-BCR/ABL protein and the expression of the early activation antigen CD(69) on CD(8)(+) and CD(4)(+) T cells was detected by flow cytometry (FCM).

The optimal concentration of PTD-BCR/ABL protein for activating CD(8)(+) T cells in vitro was 100 micro g/ml, CD(69) expression peaked in three days stimulation. CD(8)(+) T cells were activated in 10 of 15 CML patients, the expression rate of CD(69) was (15.01 +/- 3.75)%. CD(4)(+) T cells were activated in 4 of 15 patients, the expression rate of CD(69) was (10.32 +/- 3.08)%. Both CD(8)(+) and CD(4)(+) T cells were activated simultaneously in 3 of them. However, neither CD(4)(+) nor CD(8)(+) T cells was activated by stimulation with BCR/ABL protein in all 15 specimens, the expression rate of CD(69) on CD(8)(+) and CD(4)(+) T cells was (1.36 +/- 0.31)% and (1.41 +/- 0.43)%, respectively. There was no difference compared with that of PBS control group (P > 0.05).

By using a PTD-mediated antigen delivering system, exogenous BCR/ABL protein can be delivered into APC, processed and presented onto surface of APC to activate Ag-specific CD(8)(+) and CD(4)(+) T cells in vitro.