Abstract
OBJECTIVE:To investigate the expression of membrane glucocorticoid receptors (mGCR) on peripheral blood mononuclear cells (PBMC) in patients with ankylosing spondylitis (AS). METHODS: We used high sensitivity immunofluorescence with magnetofluorescent liposomes for the detection of mGCR on PBMC from patients with AS (n = 26) and healthy controls (n = 11). RESULTS: The frequency of mGCR+ monocytes and B lymphocytes was significantly higher in patients with AS than in controls (monocytes 12.5 +/- 9.9% vs 4.8 +/- 1.4%, B lymphocytes 8.7 +/- 6.3% vs 4.4 +/- 3.6%). We did not find mGCR on T lymphocytes. The frequency of mGCR+ cells did not correlate with variables of AS disease activity [C-reactive protein, erythrocyte sedimentation rate, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), BASDAI 6, or numerical rating scales]. CONCLUSION: mGCR are upregulated in monocytes and B lymphocytes of patients with AS. This upregulation does not correlate with the humoral or overall disease activity. mGCR are not present on T lymphocytes. Our findings may be related to the limited benefit of low-dose and the efficacy of high-dose (intravenous pulse or intraarticular) glucocorticoid treatment in AS. Drugs binding selectively to mGCR may be a new therapeutic option for AS.
