Fig. 3

TAM/CXCL1 signaling promotes the differentiation and the immunosuppressive function of Tregs. a TAM/shCXCL1 cells were generated by transfecting Raw264.7-derived TAMs with CXCL1 shRNAs. b Naive CD4⁺ T cells (CD4⁺/CD25⁻/CD45RA⁺) were sorted from murine spleens by fluorescence-activated cell sorting technology. c The proliferation of naive CD4⁺ T cells when treated as indicated for 24 h was investigated by CFSE staining assay and flow cytometry. d The differentiation levels of naive CD4⁺ T cells into Tregs when treated as indicated for 24 h were detected by flow cytometry. e Chemotaxis assay was conducted to investigate the chemotaxis efficacy of naive CD4⁺ T cells. f The sorting strategies of Tregs and CD8⁺ T cells. Tregs and CD8⁺ T cells were sorted from murine spleens by fluorescence-activated cell sorting technology. g–h Tregs, cytotoxic CD8⁺T cells, and 4T1 cells were co-cultured at a ratio of 1: 10: 2 and treated as indicated for 24 h. The proliferation activities, apoptosis (g), as well as granzyme B and perforin secretion levels h of CD8⁺T cells were detected by flow cytometry. The LDH activity of the 4T1 cells (h) was investigated using the colorimetric assay. N = 3. *p < 0.05; **p < 0.01