Biochemical and functional characterization of three activated macrophage populations

J Leukoc Biol. 2006 Dec;80(6):1298-307. doi: 10.1189/jlb.0406249. Epub 2006 Aug 11.


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.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Arginase / biosynthesis
  • Arginase / immunology
  • B7-2 Antigen / immunology
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Coculture Techniques
  • Cytokines / biosynthesis
  • Cytokines / immunology*
  • Cytokines / pharmacology
  • Intercellular Signaling Peptides and Proteins
  • Lipopolysaccharides / pharmacology
  • Macrophage Activation / drug effects
  • Macrophage Activation / immunology*
  • Macrophages / classification
  • Macrophages / enzymology
  • Macrophages / immunology*
  • Mice
  • Mice, Inbred BALB C
  • Nerve Growth Factor / biosynthesis
  • Nerve Growth Factor / immunology
  • Nitric Oxide / biosynthesis
  • Nitric Oxide / immunology
  • Phosphotransferases (Alcohol Group Acceptor) / biosynthesis
  • Phosphotransferases (Alcohol Group Acceptor) / immunology
  • Proteins / immunology
  • Th1 Cells / immunology
  • Th2 Cells / immunology
  • Tumor Necrosis Factor Ligand Superfamily Member 14 / biosynthesis
  • Tumor Necrosis Factor Ligand Superfamily Member 14 / immunology


  • B7-2 Antigen
  • Cd86 protein, mouse
  • Cytokines
  • Intercellular Signaling Peptides and Proteins
  • Lipopolysaccharides
  • Proteins
  • Retnla protein, mouse
  • Tnfsf14 protein, mouse
  • Tumor Necrosis Factor Ligand Superfamily Member 14
  • Nitric Oxide
  • Nerve Growth Factor
  • Phosphotransferases (Alcohol Group Acceptor)
  • sphingosine kinase
  • Arginase