Biochemical and functional characterization of three activated macrophage populations

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.…

• NI
  National Institutes of Health

  Award: AI49383