Characterization of IL-4 receptor components expressed on monocytes and monocyte-derived macrophages: variation associated with differential signaling by IL-4

Growth Factors. 2001;19(4):207-18. doi: 10.3109/08977190109001087.

Abstract

The anti-inflammatory effects of IL-4 on activated monocytes differ from those on monocyte-derived macrophages (MDMac). While IL-4 suppresses LPS-induced IL-1beta , IL-12, IL-10 and TNFalpha production by monocytes, IL-4 suppresses only IL-1beta and IL-12 production by MDMac. The U937 and Mono Mac 6 cell lines have similar cytokine responses to IL-4 as monocytes and MDMac, respectively. The IL-4Ralpha and IL-2Rgamma (gammac) chains are well-characterized components of the IL-4 receptor. Cross-linking studies with 125I-IL-4 revealed that for monocytes and U937 cells, the binding of IL-4 to the receptor components was approximately 1:1 for IL-4Ralpha:gammac. In contrast, for MDMac and Mono Mac 6 cells that have a relative reduction in gammac surface expression, the binding of IL-4 to IL-4Ralpha:gammac was approximately 3:1. Furthermore, IL-4 induced IL-4Ralpha chain phosphorylation more rapidly in MDMac and Mono Mac 6 cells than in monocytes and U937 cells. This study identifies a correlation between altered 125I-IL-4 cross-linking to IL-4Ralpha:gammac, IL-4-induced signaling and regulation of pro-inflammatory cytokine production by IL-4.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Cell Differentiation
  • Cross-Linking Reagents / pharmacology
  • Cytokines / metabolism
  • Dimerization
  • Flow Cytometry
  • Glycosylation
  • Humans
  • Interleukin-4 / metabolism*
  • Iodine / pharmacology
  • Macrophages / metabolism*
  • Monocytes / metabolism*
  • Phosphorylation
  • Precipitin Tests
  • Receptors, Interleukin-4 / chemistry*
  • Signal Transduction*
  • Time Factors
  • Tumor Cells, Cultured
  • U937 Cells

Substances

  • Cross-Linking Reagents
  • Cytokines
  • Receptors, Interleukin-4
  • Interleukin-4
  • Iodine