Methods
We conducted co-culture experiments involving melanoma cell lines and iNKT cells.
Results
We demonstrated that melanoma cell lines had a significant impact on the proliferation and functions of iNKT cells. Our findings revealed that co-culture with melanoma cell lines led to a significant impairment in the expression of the NKG2D receptor and cytolytic granules in iNKT cells. Moreover, we observed a strong impairment of their cytotoxic capability induced by the presence of melanoma cells. Furthermore, through the use of selective inhibitors targeting IDO1 and COX-2, we successfully demonstrated that the melanoma cell line's ability to impair iNKT cell activation and functions was attributed to the up-regulation of IDO1 expression and PGE2 production.