Phenotypic, Functional, and Gene Expression Profiling of Peripheral CD45RA+ and CD45RO+ CD4+CD25+CD127^low Treg Cells in Patients With Chronic Rheumatoid Arthritis

Abstract

ObjectiveConflicting evidence exists regarding the suppressive capacity of Treg cells in the peripheral blood (PB) of patients with rheumatoid arthritis (RA). The aim of this study was to determine whether Treg cells are intrinsically defective in RA.MethodsUsing a range of assays on PB samples from patients with chronic RA and healthy controls, CD3+CD4+CD25+CD127low Treg cells from the CD45RO+ or CD45RA+ T cell compartments were analyzed for phenotype, cytokine expression (ex vivo and after in vitro stimulation), suppression of Teff cell proliferation and cytokine production, suppression of monocyte‐derived cytokine/chemokine production, and gene expression profiles.ResultsNo differences between RA patients and healthy controls were observed with regard to the frequency of Treg cells, ex vivo phenotype (CD4, CD25, CD127, CD39, or CD161), or proinflammatory cytokine profile (interleukin‐17 [IL‐17], interferon‐γ [IFNγ], or tumor necrosis factor [TNF]). FoxP3 expression was slightly increased in Treg cells from RA patients. The ability of Treg cells to suppress the proliferation of T cells or the production of cytokines (IFNγ or TNF) upon coculture with autologous CD45RO+ Teff cells and monocytes was not significantly different between RA patients and healthy controls. In PB samples from some RA patients, CD45RO+ Treg cells showed an impaired ability to suppress the production of certain cytokines/chemokines (IL‐1β, IL‐1 receptor antagonist, IL‐7, CCL3, or CCL4) by autologous lipopolysaccharide‐activated monocytes. However, this was not observed in all patients, and other cytokines/chemokines (TNF, IL‐6, IL‐8, IL‐12, IL‐15, or CCL5) were generally suppressed. Finally, gene expression profiling of CD45RA+ or CD45RO+ Treg cells from the PB revealed no statistically significant differences between RA patients and healthy controls.ConclusionOur findings indicate that there is no global defect in either CD45RO+ or CD45RA+ Treg cells in the PB of patients with chronic RA.

Comparative analysis of immune cell subsets in peripheral blood from patients with periodontal disease and healthy controls

“…Regarding T regs , as expected [18] there was a slightly higher percentage of CD25 + CD127 low T cells within the CD4 + CD45RO + T cell population (on average 10%) when compared to CD4 + CD45RA + or total CD4 + T cells (on average 5 and 7%, respectively), but the frequencies between the groups were not statistically significantly different ( Fig. 2b and data not shown).…”

Leveraging blood and tissue CD4+ T cell heterogeneity at the single cell level to identify mechanisms of disease in rheumatoid arthritis

“…Unfortunately, studies of peripheral blood T cells in RA have often yielded inconsistent results. For example, the abundance of regulatory T cells (T REG ) in RA peripheral blood has been observed to be reduced or expanded compared to healthy controls in different studies [33–37]; in addition, conflicting results have been reported concerning the suppressive capability of T reg cells in RA [38–42]. Inconsistent results can be partially attributed to variation in markers used across different studies or the difficulty of resolving highly heterogeneous populations with bulk cell assays – which advancing single cell technologies might help to obviate.…”

Osteoimmunology: from mice to humans

“…However, studies on Tregs phenotype and function in RA patients have yielded conflicting results: some studies found a decrease in Tregs in peripheral blood from RA patients; 12,13 whereas others did not. 14,15 In experimental models of arthritis, Tregs have been shown to inhibit OC formation and activity. 16 These data have been confirmed by our group in humans as well, during periprosthetic osteolysis.…”