Splenectomy restores β2ARKO leukocyte infiltration into the heart following MI. (A) Representative CD68, tryptase, and MPO staining of the border or infarct zones of hearts 4d following MI surgery in WT or β2ARKO BMT that received sham and splenectomy surgery. Quantification of CD68 (B), tryptase (C) and MPO (D) staining in the border and infarct zones of 4d post-MI hearts from sham and splenectomy WT and β2ARKO BMT mice. n=6 for WT BMT Sham/MI, n=5 for WT BMT Splen/MI, n=6 for β2ARKO BMT Sham/MI, n=7 for β2ARKO BMT Splen/MI, Exact Wilcoxon rank-sum tests with multiple comparison adjustment (6 comparisons), * p < 0.05, † p < 0.01, ns = not significant.