LGALS9 and HIV-1 infection: In vitro, Gal-9 downregulated TIM-3 on NK cells and triggered NK cell activation in HIV-1 infection; however, a subset of these NK cells (immature CD56bright NK cells) were not affected by this decrease in TIM-3 expression; rather, an increase in the surface expression of TIM-3 was witnessed with a concomitant increase in Gal-9 expression during late primary HIV-1 infection (258).