Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2010 Sep;131(1):107-17.
doi: 10.1111/j.1365-2567.2010.03280.x. Epub 2010 May 6.

Interferon-alpha regulates the dynamic balance between human activated regulatory and effector T cells: implications for antiviral and autoimmune responses

Amit Golding  1 , Antony Rosen, Michelle Petri, Ehtisham Akhter, Felipe Andrade
Affiliations

Interferon-alpha regulates the dynamic balance between human activated regulatory and effector T cells: implications for antiviral and autoimmune responses

Amit Golding et al. Immunology. 2010 Sep.

Erratum in

  • Immunology. 2011 May;133(1):141

Abstract

An adequate effector response against pathogens and its subsequent inactivation after pathogen clearance are critical for the maintenance of immune homeostasis. This process involves an initial phase of T-cell effector (Teff) activation followed by the expansion of regulatory T cells (Tregs), a unique cell population that limits Teff functions. However, significant questions remain unanswered about the mechanisms that regulate the balance between these cell populations. Using an in vitro system to mimic T-cell activation in human peripheral blood mononuclear cells (PBMC), we analysed the patterns of Treg and Teff activation, with special attention to the role of type I interferon (IFN-I). Interestingly, we found that IFN-alpha, either exogenously added or endogenously induced, suppressed the generation of CD4(+) FoxP3(HI )IFN-gamma(Neg) activated Tregs (aTregs) while simultaneously promoting propagation of CD4(+) FoxP3(Low/Neg )IFN-gamma(Pos) activated Teffs (aTeffs). We also showed that IFN-alpha-mediated inhibition of interleukin (IL)-2 production may play an essential role in IFN-alpha-induced suppression of aTregs. In order to test our findings in a disease state with chronically elevated IFN-alpha, we investigated systemic lupus erythematosus (SLE). Plasma from patients with SLE was found to contain IFN-I activity that suppressed aTreg generation. Furthermore, anti-CD3 activated SLE PBMCs exhibited preferential expansion of aTeffs with a very limited increase in aTreg numbers. Together, these observations support a model whereby a transient production of IFN-alpha (such as is seen in an early antiviral response) may promote CD4 effector functions by delaying aTreg generation, but a chronic elevation of IFN-alpha may tip the aTeff:aTreg balance towards aTeffs and autoimmunity.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Analysis of FoxP3, IFN-γ, IL-2 and Ki-67 expression in CD4+ cells from anti-CD3 activated human PBMC. Freshly isolated PBMC on day 0 (a–c) were incubated in the absence (d–f) or presence of soluble anti-CD3 at 100 (g–i), 5 and 1000 ng/ml (data not shown). Cells were stained for CD4 and FoxP3, as well as IFN-γ (a, d, g), IL-2 (b, e, h) or Ki-67 (c, f, i). Numbers in quadrants indicate the per cent of CD4 T cells. Data are representative of three separate experiments. IFN-γ, interferon-γ; IL-2, interleukin-2; PBMC, peripheral blood mononuclear cells.
Figure 2
Figure 2
The distinct CD4+ FoxP3HI cell population in activated PBMC is generated from nTregs. (a) ‘Whole’ or ‘CD25-depleted’ (using magnetic beads; Miltenyi Biotec, Auburn, CA) PBMC were anti-CD3 activated. After 3 days, CD4+ T cells were analysed for CD25 and FoxP3 expression. (b) CFSE-labelled CD25Neg cells were tested by FACS for division by CFSE dilution at day 6 or 9 of culture in anti-CD3-activated whole or CD25-depleted PBMC from (a). Numbers indicate the per cent of cells that have undergone division based on CFSE dilution. Data are representative of two separate experiments. CFSE, carboxyfluorescein succinimidyl ester; FACS, fluorescence-activated cell sorting; nTregs, natural regulatory T cells; PBMC, peripheral blood mononuclear cells.
Figure 3
Figure 3
IFN-α suppresses Treg activation while increasing the number of activated IFN-γPos Teffs in anti-CD3-stimulated PBMC. PBMC were incubated with medium alone (data not shown), or with anti-CD3 in the absence (control) or presence of 100 or 1000 U/ml of IFN-α. After 3 days, the cells were stained and analysed by FACS for FoxP3 and IFN-γ expression in CD4+ lymphocytes. The numbers of total CD4 T cells, CD4+ FoxP3HIIFN-γNeg aTregs, and CD4+ FoxP3Low/NegIFN-γPos aTeffs are shown in the bar graphs in (a), (c) and (e), respectively. In order to compare the effects of IFN-α between the donors, the data were normalized to controls (which were set as 100%), and averaged over all seven donors for total CD4 T cells (b), aTregs (d), and Teffs (f). The error bars represent the standard deviation. aTregs, activated regulatory T cells; FACS, fluorescence-activated cell sorting; IFN-α, Interferon-alpha; IFN-γ, Interferon-gamma; PBMC, peripheral blood mononuclear cells; Teffs, effector T cells; Treg, regulatory T cell.
Figure 4
Figure 4
TLR3 agonism suppresses anti-CD3-mediated Treg expansion in an IFN-I-dependent fashion. Prior to the addition of anti-CD3, PBMC were incubated overnight with medium alone (control), or poly(I:C) (n = 8) in the absence or presence of IFNRAB (n = 6), anti-IL-6 (n = 3) or anti-TNF-α (n = 3). After 3 days of anti-CD3 stimulation, the cells were stained and analysed by FACS for FoxP3 and IFN-γ expression in CD4+ cells. The data were normalized to controls (i.e. anti-CD3 alone, which was set as 100%) and averaged to show the per cent change in total CD4 T cells, aTregs and aTeffs. The error bars represent the standard deviation. Cell numbers for total CD4 T cells, aTregs and aTeffs are shown in Fig. S2. aTeffs, activated effector T cells; aTregs, activated regulatory T cells; FACS, fluorescence-activated cell sorting; IFN-I, interferon-I; IL-6, interleukin-6; PBMC, peripheral blood mononuclear cells; TLR3, Toll-like receptor 3; TNF, tumour necrosis factor; Treg, regulatory T cell.
Figure 5
Figure 5
IFN-α suppresses Treg expansion by inhibiting IL-2 production. (a) PBMC from three separated donors were activated with anti-CD3 without (control) or with 1000 U/ml of IFN-α, and IL-2 was determined in the supernatants by ELISA at 24 and 48 hr post-activation. Values are shown as percentages in which 100% represents IL-2 production in control anti-CD3-stimulated PBMC. Quantification of IL-2 (pg/ml) by ELISA was as follows. Donor 1 at 24 hr minus IFN-α, 202; plus IFN-α, 101; 48 hr minus IFN-α, 34; plus IFN-α, 24. Donor 2 at 24 hr minus IFN-α, 1546; plus IFN-α, 1023; 48 hr minus IFN-α, 1416; plus IFN-α, 452. Donor 3 at 24 hr minus IFN-α, 1020; plus IFN-α, 641; 48 hr minus IFN-α, 597; plus IFN-α, 208. (b) Exogenous IL-2 can restore Treg expansion in the presence of IFN-I. PBMC from three separate donors were activated with anti-CD3 in the absence (control) or presence of 1000 U/ml of IFN-α, or 1000 U/ml of IFN-α plus 100 U/ml of IL-2. After 3 days, the cells were stained and analysed by FACS for FoxP3 and IFN-γ expression in CD4+ cells. The number and mean values of CD4+ FoxP3HIIFN-γNeg Tregs are shown. The error bars represent the standard deviation. ELISA, enzyme linked immunosorbent assay; FACS, fluorescence-activated cell sorting; IFN-α, interferon-alpha; IL-2, interleukin-2; PBMC, peripheral blood mononuclear cells; Treg, regulatory T cell.
Figure 6
Figure 6
The aTreg:aTeff ratio is altered by the IFN-I environment in SLE. (a) Prior to anti-CD3 activation, PBMC from a healthy donor were incubated overnight with plasma from four patients with SLE with moderate disease activity [SLEDAI shown in (b)] or from two healthy donors, in the absence or presence of IFNRAB. The expansion of Tregs versus Teffs was determined by FACS at day 3 post-anti-CD3 stimulation. The aTreg:aTeff ratio in the absence or presence of IFNRAB is shown in (a). (b–d) PBMCs from the same SLE donors shown in (a) were activated with anti-CD3 to determine Treg and Teff activation. The number of CD4+ CD25+ FoxP3+ cells in freshly isolated cells (day 0) and the expanded Tregs and Teffs at day 3 post-anti-CD3 activation were determined by FACS. The CD4+ CD25+ FoxP3+ starting Treg population and generated CD4+ FoxP3HiIFN-γNeg aTregs (day 0 and day 3, respectively) are expressed in (b) as a percentage of total CD4 T cells. The numbers of aTregs and aTeffs at day 3 post-activation are shown in (c), and the aTreg:aTeff ratio is shown in (d) for each of four SLE donors. aTeff, activated effector T cell; aTreg, activated regulatory T cell; FACS, fluorescence-activated cell sorting; IFN-I, interferon-I; PBMC, peripheral blood mononuclear cells; SLE, systemic lupus erythematosus.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Tang Q, Bluestone JA. The Foxp3+ regulatory T cell: a jack of all trades, master of regulation. Nat Immunol. 2008;9:239–44. - PMC - PubMed
    1. Sakaguchi S, Ono M, Setoguchi R, et al. Foxp3+ CD25+ CD4+ natural regulatory T cells in dominant self-tolerance and autoimmune disease. Immunol Rev. 2006;212:8–27. - PubMed
    1. Hori S, Nomura T, Sakaguchi S. Control of regulatory T cell development by the transcription factor Foxp3. Science. 2003;299:1057–61. - PubMed
    1. Gavin MA, Torgerson TR, Houston E, et al. Single-cell analysis of normal and FOXP3-mutant human T cells: FOXP3 expression without regulatory T cell development. Proc Natl Acad Sci U S A. 2006;103:6659–64. - PMC - PubMed
    1. Ziegler SF. FOXP3: not just for regulatory T cells anymore. Eur J Immunol. 2007;37:21–3. - PubMed

Publication types

MeSH terms