CD8A and neoplasm: Analysis of the BsAb treatment-induced in vivo immune response targeting the TME revealed enhanced infiltration of CD8-positive T cells (Fig. 3J) and a reduced percentage of myeloid-derived suppressor cells (MDSCs) and M2 TAMs (Fig. 3K-L) in the tumor specimens of BsAb-treated mice compared with those in tumors from the PD-1 scFv-, TREM2 scFv-, and PBS-treated groups.