Fig. 2: IL-35 inhibits human NK cell proliferation but not survival.

a Schematic representation of the experimental protocol. NK cells were labeled with CTV at day 0 (D0), pre-activated for 16 h as indicated, and cultured in low dose IL-2 (100 UI/mL) with or without IL-35 (100 ng/ml) for 3, 5, 7, and 9 days (D3, D5, D7, D9, respectively). Images were provided by Servier Medical Art (https://smart.servier.com/), licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). b Representative flow cytometry plots for CTV fluorescence intensity for all pre-activation conditions and c, d quantification of % cycling cells and number of cells that were primed in medium and after 3, 5, 7, and 9 days of proliferation in IL-2 versus IL-2 + IL-15. Mean values ± S.D are shown (n = 4 to 5, and 3 individual donors, respectively). e Quantification of the proportion of viable NK cells for all pre-activation conditions after 3, 5, 7 and 9 days of proliferation in IL-2 with or without IL-35. Results are expressed as fold change compared to the IL-2 control condition without IL-35. Mean values ± S.D are shown (n = 3 to 5 individual donors). Statistical significance was determined using paired T test. Source data are provided as a Source Data file.