To further explore the underlying mechanism of enhanced immunotherapy efficacy provoked by GdOFBAu in combination with anti-PD1 antibodies, we detected the proportion of tumor-infiltrating T-cells (CD4+/CD8+, CD4+/CD25+) in tumors stripped from the euthanized mice after different treatments by immunofluorescence (IF) experiments. Here, CD4 is linked to neoplasm.