Anti-tumoral Effects of Recombinant Strain Secreting IL-17A Cytokine.

Interleukin-17A (IL-17A) is a pro-inflammatory cytokine produced by T cells that participates and contributes in host defense and autoimmune disease. We have recently reported antitumor properties of the probiotic strain of BL23 in mice and T cells was shown to play an important role in this beneficial effect. In order to better understand the role of IL-17A in cancer, we constructed a recombinant strain of producing this cytokine and we determined its biological activity in: (i) a bioassay test for the induction of IL-6 production by murine fibroblasts 3T3 L1 cells line and (ii) in a mouse allograft model of human papilloma virus (HPV)-induced cancer. Our data show that recombinant produces and efficiently secretes biologically active IL-17A cytokine. Interestingly, ∼26% of mice intranasally treated with -IL-17A and challenged with TC-1 cells remained tumor free over the experiment, in contrast to control mice treated with the wild type strain of which developed 100% of aggressive tumors. In addition, the median size of the ∼74% tumor-bearing mice treated with recombinant -IL-17A, was significantly lower than mice treated with -wt. Altogether, our results demonstrate that intranasal administration with secreting IL-17A results in a partial protection against TC-1-induced tumors in mice, confirming antitumor effects of this cytokine in our cancer model.