title: Biochemical and functional characterization of three activated macrophage populations.
abstract: We generated three populations of macrophages (Mphi) in vitro and characterized each. Classically activated Mphi (Ca-Mphi) were primed with IFN-gamma and stimulated with LPS. Type II-activated Mphi (Mphi-II) were similarly primed but stimulated with LPS plus immune complexes. Alternatively activated Mphi (AA-Mphi) were primed overnight with IL-4. Here, we present a side-by-side comparison of the three cell types. We focus primarily on differences between Mphi-II and AA-Mphi, as both have been classified as M2 Mphi, distinct from Ca-Mphi. We show that Mphi-II more closely resemble Ca-Mphi than they are to AA-Mphi. Mphi-II and Ca-Mphi, but not AA-Mphi, produce high levels of NO and have low arginase activity. AA-Mphi express FIZZ1, whereas neither Mphi-II nor Ca-Mphi do. Mphi-II and Ca-Mphi express relatively high levels of CD86, whereas AA-Mphi are virtually devoid of this costimulatory molecule. Ca-Mphi and Mphi-II are efficient APC, whereas AA-Mphi fail to stimulate efficient T cell proliferation. The differences between Ca-Mphi and Mphi-II are more subtle. Ca-Mphi produce IL-12 and give rise to Th1 cells, whereas Mphi-II produce high levels of IL-10 and thus, give rise to Th2 cells secreting IL-4 and IL-10. Mphi-II express two markers that may be used to identify them in tissue. These are sphingosine kinase-1 and LIGHT (TNF superfamily 14). Thus, Ca-Mphi, Mphi-II, and AA-Mphi represent three populations of cells with different biological functions.
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
authors.forename: Justin P
authors.initials: JP
authors.lastname: Edwards
authors.forename: Xia
authors.initials: X
authors.lastname: Zhang
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Frauwirth
authors.forename: David M
authors.initials: DM
authors.lastname: Mosser
mesh_terms: D000818:Animals; D001119:Arginase / Q000096:biosynthesis / Q000276:immunology; D051940:B7-2 Antigen / Q000276:immunology; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology* / Q000494:pharmacology; D036341:Intercellular Signaling Peptides and Proteins; D008070:Lipopolysaccharides / Q000494:pharmacology; D008262:Macrophage Activation / Q000187:drug effects / Q000276:immunology*; D008264:Macrophages / Q000145:classification / Q000201:enzymology / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D020932:Nerve Growth Factor / Q000096:biosynthesis / Q000276:immunology; D009569:Nitric Oxide / Q000096:biosynthesis / Q000276:immunology; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000096:biosynthesis / Q000276:immunology; D011506:Proteins / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D053326:Tumor Necrosis Factor Ligand Superfamily Member 14 / Q000096:biosynthesis / Q000276:immunology; D000099157:Sphingosine Kinase
chemical_list: D001119:Arginase; D051940:B7-2 Antigen; D016207:Cytokines; D036341:Intercellular Signaling Peptides and Proteins; D008070:Lipopolysaccharides; D020932:Nerve Growth Factor; D009569:Nitric Oxide; D017853:Phosphotransferases (Alcohol Group Acceptor); D011506:Proteins; D053326:Tumor Necrosis Factor Ligand Superfamily Member 14; D000099157:Sphingosine Kinase; C497965:Cd86 protein, mouse; C413576:Retnla protein, mouse; C505915:Tnfsf14 protein, mouse