Table 1.
Summary of the studies analyzing synovial MCs in RA patients.
| Year | Title | Disease Duration | Procedure (Joint Site) | Patients (n) | Main Results |
|---|---|---|---|---|---|
| Crisp et al. 1984 [32] | Articular mastocytosis in rheumatoid arthritis | Long-standing | Synoviectomy (wrist and knee) and joint replacement (knee) | 116 | Higher MC numbers in RA vs. healthy samples. Correlation with synovitis but not with ESR. Caveat treatment. |
| Godfrey et al. 1985 [33] | Mast Cells in Rheumatoid Arthritis and Other Rheumatic Diseases | Long-standing | Synoviectomy or joint replacement | 14 | Higher MC numbers in RA. Association with clinically active disease. |
| Malone et al. 1987 [34] | Mast cell numbers in rheumatoid synovial tissues. | Long-standing | Knee arthroscopy | 20 | Correlation with synovial inflammation. No attempt to look for clinical correlations. Reduction of MC numbers after IA steroids. |
| Tetlow & Woolley 1995 [35] | Distribution, activation and tryptase/chymase phenotype of mast cells in the rheumatoid | Long-standing | Joint replacement (knee) | 26 | MC present in all samples, but more abundant in 60% of patients. Higher prevalence of MC_T. No attempt to look for clinical correlations. |
| Gotis-Graham & McNeil 1997 [36] | Mast cell responses in rheumatoid synovium. Association of the MCTC subset with matrix turnover and clinical progression | Long-standing | Joint replacement or arthroscopy (knee) | 16 | Increase of MCs in RA vs. OA or healthy samples; MC_TC correlate with disease activity. |
| Gotis-Graham et al. 1998 [37] | Synovial mast cell responses during clinical improvement in early rheumatoid arthritis | Early (mean disease duration 8 months), sDMARD-naïve | Arthroscopy (knee) | 6 | Relative increase of MC_T was observed, in correlation with synovial inflammatory score. |
| Ramírez et al. 2016 [38] | Immunopathologic characterization of ultrasound-defined synovitis in rheumatoid arthritis patients in clinical remission. | Long standing; 20 patients in remission; 22 with active disease |
US-guided synovial biopsies | 42 | MCs and B cells in patients in clinical remission associated with disease reactivation. |
| Rivellese et al. 2018 [31] | Mast cells in early rheumatoid arthritis associate with disease severity and support B cell autoantibody production | Early (<12 months), steroid and sDMARD-naive | US-guided synovial biopsies (60% small joints, i.e., MCPs or wrists) | 99 | Synovial MCs are associated with (i) synovial inflammation, (ii) lympho-myeloid infiltrate, (iii) systemic inflammation, (iv) autoantibodies, and (v) disease activity. |
1 sDMARDs: synthetic disease modifying antirheumatic drugs; MC_T: MC expressing tryptase; MC_TC: MC expressing tryptase and chymase; MCP: metacarpophalangeal, n: number of patients.