Phenotypical studies of Mac1⁺ granular cells. Two to 5 chimeras were killed at week 3 after BMT, spleen cells were pooled, and 2-color flow cytometry was performed for expression of Mac1 and a panel of other surface markers within the gated Mac1⁺ granular cell population. Dot plots are from 1 of 3 representative experiments and show Mac1⁺ granular cells gated as indicated in the top left panel.