PTPRC and tuberculosis: With further examination of the PD-L1+ population in CD45− cells, our data showed that all of the CD45− populations expressed a minimal level of PD-L1 (<0.1%), including CD45− cells from the TB spleens, A223 tumors and KPPA tumors, which was significantly lower than that in CD45+CD11b+ population in the TB spleens (Figure 4D).