FoxP3⁺CD39⁺ Treg cells are increased during acute MS.

<p>Scatter plots from three representative subjects, one healthy donor (HC; <b>A</b>), a stable MS patients (<b>B</b>), and a patient experiencing a clinical re-exacerbation of MS (<b>C</b>) are shown, indicating that the FoxP3/CD39 double positive T cell population (<b>A</b>, right panel) in the CD25^high gate dramatically decreases during stable MS (<b>B</b>, right panel) and is restored during an acute attack (<b>C</b>, right panel).</p

Treg cells are increased during acute MS.

<p>The percentage of FoxP3⁺ cells in the CD4⁺CD25^high gate is shown in (<b>A</b>) in healthy controls (HC; n = 14), stable MS (n = 10), and acute MS (n = 8). The percentage of CD39⁺ cells in the CD4⁺CD25^high gate is shown in (<b>B</b>) in HC (n = 44), stable MS (n = 31), and acute MS (n = 32), and, similarly, the percentage of FoxP3⁺/CD39⁺ cells in the CD4⁺CD25^high gate is displayed in (<b>C</b>) in HC (n = 13), stable MS (n = 12), and acute MS (n = 11). Again, while Treg cells, as defined by these markers, were significantly decreased in stable MS patients and restored during an acute attack. Lines represent median values, and P values are indicated where significant (Mann-Whitney). CD4+CD25^highCD39⁺ regulatory T cells from an acute MS patient suppress T responder cell proliferation (E) in a dose dependent way (F), as measured by CFSE dilution assay. Plots represent CFSE-labeled T responder cell proliferation in absence and presence of regulatory T cell (5∶1) (E, F). A representative experiment among three is shown. Treatment-free RR-MS patients (n = 15) were followed longitudinally every two months for 14 months (<b>G–H</b>), and divided according to the occurrence of clinical relapses during the follow-up in stable (G), or relapsing (H) patients. PBMC <i>foxp3</i> mRNA values, normalized on CD4 and GAPDH mRNA, and expressed as arbitrary units (AU) are plotted.</p

CD4⁺CD25^highCD39⁺ T cells express increased levels of Treg markers.

<p>FoxP3 (<b>A</b>), CTLA4 (<b>B</b>) and GITR (<b>C</b>) expression, as measured by flow cytometry, are increased in CD4⁺CD39⁺, as compared to CD4⁺CD39⁻ T cells, especially in the CD25^high compartment.</p

Treg markers are up-regulated in RR-MS patients experiencing clinical relapses.

<p><b>A–E.</b> Clinically relapsing RR-MS patients displayed increased PBMC mRNA levels for CD25 (<b>A</b>), CTLA-4 (<b>B</b>), GITR (<b>C</b>), CD39 (<b>D</b>), and foxp3 (<b>E</b>). We also found significantly lower levels of Treg markers mRNA in stable RR-MS patients as compared to healthy controls (HC). Values are expressed as arbitrary units (AU). P values are indicated (Mann-Whitney).</p