Study on anti ovarian cancer efficacy elicited by CD34~+ umbilical cord blood hematopoietic stem cells transfected with IL-21 in nude mouse model

Abstract

Objective To investigate the CD34~+ umbilical cord blood hematopoietic stem cells (CD34~+ UBSC) transfected with interleukin 21 (IL-21) against the ovarian cancer effect in tumor-bearing nude mice. Methods CD34~+ UBSC were obtained from the UBSC by a magnetically activated cell sorting technique and then transfected with recombinant plasmid plRES2-IL-21-EGFP after the CD34~+ UBSC were proliferated in vitro. The therapeutic effect was evaluated by the size of the tumor and the life span in nude mice treated with the CD34~+ UBSC-IL-21. The expression of IL-21 and its bioactivity in CD34~+ UBSC-IL-21 and in local neoplasitc tissues were respectively detected by reverse transcription-polymerase chain reaction (RT-PCR), immune fluorescence technique, ELISA, Western blot, immunohistochemistry and splenocyte proliferative activity. The NK cell cytotoxicity and the numbers of NK cells, serum level of IFN-γ and TNF-αwere simultaneouly detected by FCM and ELISA, respectively. Results CD34~+ UBSC were cultured and transfected with pIRES2-IL-21-EGFP successfully. CD34~+ UBSC-IL-21 could inhibit the tumor growth and extended nude mice life span compared with other groups (P < 0.01). The expression of IL-21 in the neo-plastic tissue, serum level of IFN-γ and TNF-α , NK cell activity and the numbers of NK cells of mice origin and of human origin in splenocytes were increased significantly in the nude mice treated with CD34~+ UBSC-IL-21 compared with other groups(P <0.01). Conclusion The CD34~+ UBSC transfected with IL-21 have competent against ovarian cancer in tumor-bearing nude mice. The findings may establish a foundation for gene therapy of the ovarian cancer by CD34~+ UBSC-IL-21 in clinic application. Key words: CD34~+ umbilical cord blood hematopoietic stem cell ; Interleukin 21 ; Ovarian cancer