Figure 1: Expression and secretion of CXCL1 in vitro and in vivo. (a) Levels of CXCL1 in the serum of naive mice () or 3LL tumor-bearing mice () were measured by ELISA at 14 days after tumor inoculation. Each dot represents an individual mouse. (b) CXCL1 protein levels in the 3LL culture supernatants were determined by ELISA. (c) mRNA expression of CXCL1 in 3LL cells was measured by quantitative RT-PCR. (d) ELISA analysis of CXCL1 production in Lewis lung carcinoma cell line 3LL, mouse epithelial cell line MLE, and human non-small lung carcinoma cell line A549. (e) Ly6G+MPO+ neutrophils in 3LL tumor tissues were determined by IF and IHC. (f) Quantitative RT-PCR analysis of CXCL1 expression in 3LL tumor cells and TANs (sorted from 3LL tumor tissues) stimulated with or without LPS (100 ng/mL) for 6 hours. ; data are shown as mean ± SD.