Abstract:

Abstract:Objective
To observe the effect of BCG-derived HSP70（BCGHSP70） on the immunogenicity of tumor cell lysate and  provide basis for the preparation of TCL-based tumor vaccines. Methods  B16TCL was prepared from B16 melanoma cells by freeze-thaw,then directly mixed with the recombinant BCGHSP70 in vitro to generate BCGHSP70-B16TCL. C57BL/6 mice were randomly divided into 4 groups:BCGHSP70-B16TCL group,PBS group,BCGHSP70 group and B16TCL group. On days 1 and 14,the mice were injected subcutaneously with BCGHSP70-B16TCL,PBS,BCGHSP70 or B16TCL, respectively. On day 21,the mice were scarified and the splenocytes from each group were tested for their proliferative response to the stimulation of B16TCL in vitro by MTT assay,and the stimulation index (SI) of splenocytes was calculated. Results B16 melanoma cells were lysed completely by freeze-thaw,and abundant proteins were observed in the B16TCL. BCGHSP70-B16TCL immunization resulted in a significant increase in the size of spleens. The SI of splenocytes was higher in BCGHSP70-B16TCL group than those in PBS group (P=0.00),B16TCL group (P=0.01) and BCGHSP70 group (P=0.00). Conclusion BCGHSP70 could enhance the immunogenicity of B16TCL,indicating that BCGHSP70 might be used as an effective adjuvant for the TCL-based tumor vaccine.

Key words: BCG；HSP70；tumor cell lysate;immunogenicity;immune adjuvant