Aim: To explore the effect of staphylococcal enterotoxin A(SEA) on CD3(epsilon) chain expression on mononuclear cells in cord blood, which were stimulated by K562 cells.
Methods: The anti-CD3 antibodies(mAb), K562 cells, SEA or both SEA and K562 cells were cocultured with mononuclear cells (MNCs) from four normal human cord blood for 48 hours respectively, Real-time PCR with SYBR Green I technique was used to detect expressed level of CD(epsilon) on MNCs in cord blood and set up a blank control group. Relative changes in expression level of CD3(epsilon) chain were indicated by the 2(-deltadeltaCt); method between each group and the control group. beta2-microglobulin gene(beta2M) was used as an endogenous reference.
Results: The expressed level of CD3(epsilon) chain on MNCs was slightly decreased in K562 cell group and were increased in the anti-CD3 antibodies mAb group, SEA group, both of SEA and K562 cell group respectively. The expressed level of CD3(epsilon) chain in both SEA and K562 group was significantly higher than that in the SEA group(P<0.01).
Conclusion: Superantigen SEA can enhance the expressed level of CD3(epsilon) chain on MNCs stimulated by K562 cells.