PTPRC and infection: To study the recruitment of these cells during MRSA-induced pneumonia, we measured total cell numbers of alveolar macrophages (CD45+CD11c+Siglec-F+) and monocytes (CD45+CD11c−Siglec-F−Ly6-G−Ly6-C−CD11b+) in BALF before and at 6, 24, and 48 h after infection (Fig. 2A).