Fostamatinib does not alter skin inflammation in a B6 into B6D2F1 model of sclerodermatous GVHD but decreases peripheral blood Ly6C^hi monocytes. (A) Frequency of CD19⁺ B cells in spleens of mice on day 21 in vehicle-treated (gray bars), R788-treated (black bars), and non-GVHD controls (white bars). (B) Total inflammation score. (C) Absolute number of CD11b⁺ F4/80⁺ peripheral blood monocytes. Peripheral blood monocytes were examines for (D) Ly6C high or (E) Ly6C low expression. *P < .5; **P < .01. Error bars represent SEM; n = 6 per group. PB mono, peripheral blood monocyte.