Fig. 3

Chitin reduces high CHI3L1 and CHI3L3 production in the 4T1-based and even low CHI3L3 production in the 66cl4-based intraductal model. A Representative western blot images for CHI3L1, CHI3L3 and GAPDH loading control in primary tumor lysates from untreated, anti-PD-1-, chitin- and chitin + anti-PD-1-treated 4T1 and 66cl4 tumor-bearing mice at 5 w p.i. with quantification of CHI3L1 and CHI3L3 signal intensity relative to GAPDH (n = 6 for all groups; 3 western blots with 2 samples from each group per blot). B CHI3L1 primary tumor levels in the untreated and treated 4T1- (n = 5 for all groups) and 66cl4-based model (n = 11 for all groups) at 5 w p.i. C CHI3L3 primary tumor levels in the untreated and treated 4T1- (n = 5 for all groups) and 66cl4-based model (n = 11 for all groups) at 5 w p.i. D CHI3L1 serum levels in the untreated and treated 4T1- (n = 5 for all groups) and 66cl4-based model (n = 11 for all groups) at 5 w p.i. E CHI3L3 serum levels in the untreated and treated 4T1- (n = 5 for all groups) and 66cl4-based model (n = 11 for all groups) at 5 w p.i. F Fold change in CHI3L1 and CHI3L3 levels between separated CD45⁺ and CD45⁻ cells from untreated 4T1 primary tumors at 5 w p.i. (n = 3 for all groups). G Fold change in CHI3L1 and CHI3L3 levels between separated Ly6G⁺ and Ly6G⁻ cells from untreated 4T1 primary tumors at 3 w p.i. (n = 4 for all groups). H Fold change in CHI3L1 levels between Ly6G⁺ cells derived from untreated versus chitin-treated 4T1 primary tumors at 3 w p.i. (n = 4 for all groups). I Fold change in CHI3L1 levels between Ly6G⁻ cells derived from untreated versus chitin-treated 4T1 primary tumors at 3 w p.i. (n = 4 for all groups). Data are presented as the means ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001