Because macrophages presented the highest level of IL1B expression among all cells (Supplementary Figure S4A), we used CellPhoneDB (27) to characterize the interactions between macrophages and MCs in ccRCC and found that IL1B-ADRB2, CSF1R-CSF1, CD55-ADGRE5, PLXNB2-SEMA4D, and CD72-SEMA4D interactions link MCs to macrophages. The gene discussed is SEMA4D; the disease is nonpapillary renal cell carcinoma.