Figure 4.

VISTA immunostaining in controls and feline tumor samples (400x magnification). (A) Human tonsil and (B) feline lymph nodes were used as positive controls, presenting a strong (score 3+) tissue VISTA expression in lymphocytes; (C) Considering the feline tumor samples, normal mammary cells and (D) tumor interstitial compartment revealed a negative VISTA expression. (E) Triple-negative (evaluated as 70% of positive TILs, with 2+ score and 60% of positive cancer cells, with 2+ score) and (F) HER2-positive tumor subtypes (evaluated as 80% of positive TILs, with 2+ score and 100% of positive cancer cells, with 3+ score) were used to demonstrate the VISTA tissue expression in feline tumors.