Objective: In a prospective study we investigated whether numerical and functional changes of CD4+CD25high regulatory T cells (Treg) were associated with changes of disease activity observed during pregnancy and post partum in patients with rheumatoid arthritis (RA).
Methods: The frequency of CD4+CD25high T cells was determined by flow cytometry in 12 patients with RA and 14 healthy women during and after pregnancy. FACS-sorted CD4+CD25high T cells and CD4+CD25- T cells were stimulated with anti-CD3 and anti-CD28 monoclonal antibodies alone or in co-culture to investigate proliferation and cytokine secretion.
Results: Frequencies of CD4+CD25high Treg were significantly higher in the third trimester compared to 8 weeks post-partum both in patients and controls. Numbers of CD4+CD25high Treg inversely correlated with disease activity in the third trimester and post-partum. In co-culture experiments significantly higher amounts of IL-10 and lowered levels of TNFα and IFNγ were found in supernatants of the third trimester compared to post-partum samples. These findings were independent from health or disease in pregnancy, however post-partum TNFα and IFNγ levels were higher in patients with disease flares.
Conclusion: The amelioration of disease activity in the third trimester corresponded to the increased number of Treg that induced a pronounced anti-inflammatory cytokine milieu. The pregnancy related quantitative and qualitative changes of Treg suggest a beneficial effect of Treg on disease activity.
- Regulatory T-Lymphocytes
- Rheumatoid arthritis