CXCR3 and ischemia: In addition, the IbaI-positive cells were ramified in control retina, whereas many of them in the ischemia-injured retina had phagocytic (ameboid) morphology and were isolectin B4 positive, indicating an activated phenotype.25 In contrast, IbaI- and isolectin B4-positive cells were reduced in ischemic retinas of CXCR3-deficient mice and these cells exhibit a significantly less-activated phenotype.