Human and mouse macrophage expression profiles are highly conserved at the mRNA and protein levels. (A) In this study, we included variations of common human macrophage (hMΦ) models: M-CSF– or autologous serum (AS)–differentiated macrophages cultured on tissue culture plastic (TCP) or bacteriological plastic (BP). For murine macrophages (mMΦ), we included BM-derived macrophages (BMMΦ) and 2 primary macrophage populations isolated ex vivo: peritoneal macrophages elicited by injection of Biogel (BioMΦ) or inflammatory macrophages elicited by injection of thioglycollate (ThioMΦ); macrophages were cultured on different surfaces (TCP, BP, or Permanox [PP]). (B) comparing basal transcriptomes of all human macrophage culture models, we identified 489 transcripts consistently detected in the first 1000 expression-ranked genes. A total of 459 transcripts were detected in common for all murine culture models; 231 transcripts, approximately 50% of each species consensus list, were shared by human and mouse macrophages. (C) Using proteomics, we investigated the protein content of 4 macrophage models: human macrophages differentiated in the presence of M-CSF or AS and murine BMMΦ and ThioMΦ. We detected 977 and 1038 proteins in human and mouse macrophages, respectively. Of these, 513 were detected in macrophages of both species. (D) Overlap between the conserved mRNA and protein signatures; 231 highly expressed genes and 513 detected proteins, respectively, amounted to 87 genes.