ABSTRACT
Objective To investigate the effects of recombinant human fibronectin fragment (RetroNectin) combined with anti-CD3 monoclonal antibody (CD3Ab) on the proliferation and cytotoxicity of cytokine-induced killer cells (CIK) from acute leukemia (AL). Methods Mononuclear cells (MNCs) were isolated from peripheral blood of complete remission AL pa-tients. The MNCs were cultured in vitro by precoating with RetroNectin (RN group), CD3Ab (CD3Ab group), RetroNectin com-bined with CD3Ab (RN+CD3Ab group) and traditional method (control group) to generate CIK. The changes of growth rate, characterization, cytotoxicity and apoptosis of CIK were determined between groups. Results The amplification of CIK was higher in experimental group than that of control group, and the amplification of CIK was higher in group RN+CD3Ab than that of in group RN and group CD3Ab (P＜0.05). The expression of CD25 positive cells was higher in group RN and group RN+CD3Ab than that of group CD3Ab and control group (P＜0.05).The percentage of G1 stage cells was lower in group RN and group RN+CD3Ab than that of group CD3Ab and control group. The percentage of S stage cells was higher in group RN and group RN+CD3Ab than that of group CD3Ab and control group (P＜0.05). The cytotoxicity was higher in group RN and group RN+CD3Ab than that of group CD3Ab and control group (P＜0.05) at the E/T scope 40∶1.The percentage of apoptotic cells was lower in group RN and group RN+CD3Ab than that of group CD3Ab and control group (P ＜ 0.05). Conclusion These in vitro studies suggest that a higher activity of immune cells could be obtained by CIK cells cultured by precoating Ret-roNectin and CD3Ab.