Objective. To determine the cytokine profile of CD4+ T cells in the synovial tissue (ST) of rheumatoid arthritis (RA) patients at the single- cell level. Methods. Unseparated ST cells and paired CD4+ T cells separated from the peripheral blood (PB) and ST of RA patients were stimulated for 4 hours with phorbol myristate acetate (PMA) plus calcium ionophore A23187, or for 6 hours with immobilized anti-CD3 plus anti-CD28, in the presence of brefeldin A. Cells were stained for intracellular cytokines such as interferon-γ (IFNγ), interleukin-2 (IL-2), IL-4, IL-10, and IL-13, in combination with cell surface markers. The percentages of cytokine-producing T cells were analyzed by flow cytometry. Results. When ST cells were stimulated with PMA plus A23187 in bulk culture, IFNγ-producing T cells were more frequently detected in the CD8+ subset, but cells producing other cytokines were found in the CD4+ subset. Purified ST CD4+ T cells, after stimulation with PMA plus A23187, were able to produce higher levels of IFNγ but lower levels of IL-4 and IL-13, by analysis at the single-cell level, as compared with the PB CD4+, CD45RO+ T cells. The majority of IL-4- or IL-13- producing ST CD4+ cells produced IFNγ, although PB CD4+ T cells rarely showed this cytokine pattern. IL-10-producing CD4+ T cells were more frequently found in the ST than in the PB. Of interest, most of the IL-10- producing ST CD4+ T cells were able to produce IFNγ. IL-2-producing CD4+ T cells were similarly present in both compartments. Similar intracellular cytokine patterns were observed with anti-CD3 plus anti-CD28 stimulation, although the number of detected cells was lower. Conclusion. These data indicate that CD4+ T cells present within the inflamed synovium have apparently distinct cytokine profiles from those of memory CD4+ T cells in the PB, as typified by their ability to secrete both IFNγ and IL-10.
|Number of pages||8|
|Journal||Arthritis and Rheumatism|
|Publication status||Published - Sep 1 1998|
ASJC Scopus subject areas
- Immunology and Allergy
- Pharmacology (medical)