Effects of intratumoral LPS injection. B16F10 cells were subcutaneously injected into mice, and after 5 days of tumor growth LPS was intratumorally injected. Six hours after LPS injection the tumor mass and the tumor draining lymph nodes (DLN) were removed for analysis. One group received PBS instead LPS as a control. (a) MFI of CD86 in CD11c⁺ cells or CD11c⁻ cells, on tumor DLN (right graph) or tumor site (left graph), with or without LPS treatment (b) Histogram of CD86 expression by CD11c⁺ cells in tumor DLN (right graph) or tumor site (left graph) of mice with PBS (gray filled histogram) or LPS treatment (black line histogram). (c) Numbers of CD4⁺ or CD8⁺ T cells on tumor DLN (right graph) or tumor site (left graph) with or without LPS treatment. (d) Dot plot showing intratumoral CD4⁺ or CD8⁺ cells after treatment with LPS or PBS. Data representative of two different experiments, mice per group.