Furthermore, we transferred WT or Chi3l1 KO Th1 and activated CD8 T cells into RAG KO mice consistently shows that Chi3l1 KO T cell transfer shows more significantly reduced lung metastasis of melanoma cells compare to WT T cell transfer (Supplementary Fig. 5) suggesting the total KO and CD4-Chi3l1 KO mice phenotype of reduced lung metastasis would be due to altered intrinsic T cell functions. Here, CHI3L1 is linked to melanoma.