Unit

UNIT 14.22 Quantitative Assessment of Macrophage Functions in Repair and Fibrosis

  1. Thomas A. Wynn,
  2. Luke Barron,
  3. Robert W. Thompson,
  4. Satish K. Madala,
  5. Mark S. Wilson,
  6. Allen W. Cheever,
  7. Thirumalai Ramalingam

Published Online: 1 APR 2011

DOI: 10.1002/0471142735.im1422s93

Current Protocols in Immunology

Current Protocols in Immunology

How to Cite

Wynn, T. A., Barron, L., Thompson, R. W., Madala, S. K., Wilson, M. S., Cheever, A. W. and Ramalingam, T. 2011. Quantitative Assessment of Macrophage Functions in Repair and Fibrosis. Current Protocols in Immunology. 93:14.22:14.22.1–14.22.12.

Author Information

  1. National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland

Publication History

  1. Published Online: 1 APR 2011
  2. Published Print: APR 2011

Abstract

Macrophages play key roles in wound repair and fibrosis by regulating extracellular matrix turnover. Macrophages can process matrix components themselves, but also recruit and alter the functions of other cell types that directly build or degrade extracellular matrix. Classically activated macrophages (CAM, also called M1) tend to promote tissue injury while alternatively activated macrophages (AAM, also called M2) are often linked with the mechanisms of wound repair and fibrosis. However, rather than promoting collagen deposition, recent studies suggest that arginase-1-expressing AAM suppress chronic inflammation and fibrosis by inhibiting antigen-specific T cell responses. This unit describes methods to measure arginase activity in macrophages and whole tissues as well as assays to quantify the T cell suppressive activity of AAMs. Modified hydroxyproline and soluble collagen assays that can be used to quantify collagen levels in tissues and brochoalveolar lavage fluid are also described. The protocols in this unit should provide the investigator with all the necessary information required to measure arginase activity and to correlate the observed activity with the progression and resolution of fibrosis. Curr. Protoc. Immunol. 93:14.22.1-14.22.12. © 2011 by John Wiley & Sons, Inc.

Keywords:

  • urea;
  • collagen;
  • hydroxyproline;
  • immunosuppression;
  • remodeling;
  • fibrosis