ICOS and B7 costimulatory molecule expression identifies activated cellular subsets in rheumatoid arthritis

Jeffrey H. Ruth*, Janaes B. Rottman, Gillian A. Kingsbury, Anthony J. Coyle, G. Kenneth Haines, Richard M. Pope, Alisa E. Koch

*Corresponding author for this work

Research output: Contribution to journalArticle

21 Scopus citations

Abstract

To better define important cell subsets expressing activation markers in rheumatoid arthritis (RA), we compared selective lymphocyte and monocyte B7H1, B7H2, B7RP.1, B7RP.2, and inducible costimulatory molecule (ICOS) expression from normal peripheral blood (NL PB), RA PB, and RA synovial fluid (SF) by multicolor flow cytometry and immunohistochemistry. RA SF memory lymphocytes expressed B7RP.1 and B7RP.2, suggesting that T-cells may function as antigen presenting cells (APCs) in RA joints. We found similar results for ICOS expression. RA SF CD14+ monocytes also expressed B7RP.1 (an ICOS ligand) and the homologous ligand B7RP.2, identifying monocytes as potential mediators of antigen processing and lymphocyte activation in RA. Furthermore, we found an increased population of RA SF CD14+ monocytes expressing B7H1 and B7H2. [The FACS analysis was supported by immunohistochemistry, showing intense lymphocyte and APC (macrophages with dendritic morphology) ICOS staining in RA synovial tissue (ST). Overall, these results define elevated populations of memory T-lymphocytes expressing proinflammatory B7 molecules in RA SF that either stimulate T cells through ICOS (via ICOS ligands B7RP.1 and B7RP.2), or down-regulate RA ST T-lymphocytes through B7H1 and B7H2.] Therefore, in the same joint, there may exist positive and negative influences on the inflammatory response, and perhaps, the negative signals dominate as joint inflammation resolves.

Original languageEnglish (US)
Pages (from-to)317-326
Number of pages10
JournalCytometry Part A
Volume71
Issue number5
DOIs
StatePublished - May 1 2007

Keywords

  • Antigen presentation
  • B7
  • ICOS
  • Inflammation
  • Rheumatoid arthritis

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Histology
  • Cell Biology

Fingerprint Dive into the research topics of 'ICOS and B7 costimulatory molecule expression identifies activated cellular subsets in rheumatoid arthritis'. Together they form a unique fingerprint.

  • Cite this

    Ruth, J. H., Rottman, J. B., Kingsbury, G. A., Coyle, A. J., Haines, G. K., Pope, R. M., & Koch, A. E. (2007). ICOS and B7 costimulatory molecule expression identifies activated cellular subsets in rheumatoid arthritis. Cytometry Part A, 71(5), 317-326. https://doi.org/10.1002/cyto.a.20383