CD200 expression on tumor cells inhibits tumor lung metastasis in Rag1^−/− C57BL6 mice.

<p><b>A.</b> 1×10⁵ of B16.OVA.Ctrl or B16.OVA.CD200 cells were injected into each Rag1^−/− C57BL6 mouse s.c. The tumor growth was observed over time. <b>B.</b> Kaplan-Meier survival analysis and log-rank test were used to analyze mice survival. Mice with a tumor burden of 1.5×1.5 cm were sacrificed and counted as dead. Data shown in <b>A</b> and <b>B</b> represent two experiments with similar results. <b>C.</b> Rag^−/− C57BL6 mice were given 1×10⁵ B16.OVA.Ctrl or B16.OVA.CD200 cells per mouse via their tail vein. 20 days later mice were sacrificed and tumor lung metastasis was shown. <b>D.</b> Number of tumor foci in the lungs from mice shown in <b>C</b> were quantified. Error bars represent ± SEM. Student's two-tailed t test was used for the statistical analysis. <b>E.</b> Average weight of lungs from each group of mice shown in <b>C</b>. Error bars represent ± SEM. Student's two-tailed t test was used for the statistical analysis. <b>F.</b> Kaplan-Meier survival curve of mice who received i.v. injection of B16.OVA.Ctrl or B16.OVA.CD200 cells. Data shown in <b>C-F</b> represents two experiments with similar results.