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Sökning: WFRF:(Chenna Narendra Sudeep)

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1.
  • Chalise, Jaya Prakash, et al. (författare)
  • IDO1 and TGF- 1 β mediate protective effects of IFN-α in antigen-induced arthritis
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • Interferon-α (IFN-α) prevents antigen-induced arthritis (AIA) in mice by an unknown mechanism. Indoleamine 2, 3 dioxygenase 1 (IDO1) is an immunoregulator via enzymatic as well as signalling activity, which can be activated by TGF-β and further mediated via non canonical NF-κB signalling. We here investigated whether IDO1 and TGF-β are involved in IFN-α protective effects in AIA. Arthritis was induced in wt, Ido1-/- or Ifnar-/- mice, treated or not with IFN-α or kynurenine, the main IDO1 product, and antibodies neutralizing TGF-β or 1-methyltryptophan (1-MT), an inhibitor of IDO1 catalytic activity. IDO1 expression and enzymatic activity were determined by RT-PCR and HPLC, respectively. Proliferation was measured by 3H-Thymidine incorporation. Non-canonical NF-κB signalling was evaluated by ELISA and Western blot in plasmacytoid DCs (pDCs) from treated mice. Protective effects of IFN-α in AIA were associated with increased IDO1 expression and kynurenine production in spleen cells, particularly at the time of mBSA sensitization. Lack of IDO1 ablated IFN-α protection and kynurenine prevented AIA in an IFNAR-independent manner. The IDO1 catalytic activity was crucial for IFN-α effects at the sensitization but not effector phase of AIA. The disease effector phase in mice treated with IFN-α was instead characterized by sustained IDO1 and TGF-β expression and activation of the noncanonical NF-κB pathway in pDCs. IFN-α protective effects in AIA involves IDO1 enzymatic and signalling activity in the disease sensitization and effector phase, respectively. Kynurenine, the main IDO1 metabolite, can be used as an alternative treatment to IFN-α in protecting mice from AIA.
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2.
  • Chalise, Jaya Prakash, et al. (författare)
  • Interferon alpha inhibits antigen-specific production of proinflammatory cytokines and enhances antigen-specific transforming growth factor beta production in antigen-induced arthritis
  • 2013
  • Ingår i: Arthritis Research and Therapy. - London, UK : BioMed Central. - 1478-6354. ; 15:5, s. R143-
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: Interferon alpha (IFN-α) has a complex role in autoimmunity, in that it may both enhance and prevent inflammation. We have previously shown that the presence of IFN-α at sensitization protects against subsequent antigen-triggered arthritis. To understand this tolerogenic mechanism, we performed a descriptive, hypothesis-generating study of cellular and humoral responses associated with IFN-α-mediated protection against arthritis.Methods: Arthritis was evaluated at day 28 in mice given a subcutaneous injection of methylated bovine serum albumin (mBSA), together with Freund adjuvant and 0 to 5,000 U IFN-α at days 1 and 7, followed by intraarticular injection of mBSA alone at day 21. The effect of IFN-α on mBSA-specific IgG1, IgG2a, IgG2b, IgA, and IgE was evaluated by enzyme-linked immunosorbent assay (ELISA). Cytokines in circulation and in ex vivo cultures on mBSA restimulation was evaluated with ELISA and Luminex, and the identity of cytokine-producing cells by fluorescence-activated cell sorting (FACS) analysis.Results: Administration of IFN-α protected mice from arthritis in a dose-dependent manner but had no effect on antigen-specific antibody levels. However, IFN-α did inhibit the initial increase of IL-6, IL-10, IL-12, and TNF, and the recall response induced by intraarticular mBSA challenge of IL-1β, IL-10, IL-12, TNF, IFN-γ, and IL-17 in serum. IFN-α decreased both macrophage and CD4+ T cell-derived IFN-γ production, whereas IL-17 was decreased only in CD4+ T cells. Ex vivo, in mBSA-restimulated spleen and lymph node cell cultures, the inhibitory effect of in vivo administration of IFN-α on proinflammatory cytokine production was clearly apparent, but had a time limit. An earlier macrophage-derived, and stronger activation of the antiinflammatory cytokine transforming growth factor beta (TGF-β) was observed in IFN-α-treated animals, combined with an increase in CD4+ T cells producing TGF-β when arthritis was triggered by mBSA (day 21). Presence of IFN-α at immunizations also prevented the reduction in TGF-β production, which was induced by the intraarticular mBSA injection triggering arthritis in control animals.Conclusions: Administration of IFN-α has a profound effect on the cellular response to mBSA plus adjuvant, but does not affect antigen-specific Ig production. By including IFN-α at immunizations, spleen and lymph node cells inhibit their repertoire of antigen-induced proinflammatory cytokines while enhancing antiinflammatory TGF-β production, first in macrophages, and later also in CD4+ T cells. On intraarticular antigen challenge, this antiinflammatory state is reenforced, manifested as inhibition of proinflammatory recall responses and preservation of TGF-β levels. This may explain why IFN-α protects against antigen-induced arthritis. © 2013 Chalise et al.; licensee BioMed Central Ltd.
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3.
  • Chalise, Jaya Prakash, et al. (författare)
  • Regulatory T cells manifest IFN-α mediated protection during antigen induced arthritis
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • IntroductionType I interferon induces tolerance against arthritogenic antigen and protects against antigen induced arthritis (AIA). Regulatory T cells (Treg cells) resolve aberrant immune reaction, maintain self-tolerance and prevent the development of autoimmune diseases. We here investigated the impact of Interferon alpha (IFN-α) on Treg cells development and function during antigen induced arthritis.MethodsFor AIA, mice were immunized with methylated bovine serum albumin (mBSA) at day 1 and 7 in presence or absence of IFN-α. At day 21, arthritis was induced by intra-articular injection of mBSA and arthritis was evaluated at day 28. At various days of AIA, CD4, CD25, Foxp3 and CTLA-4 expression was quantified by FACS in blood cells, splenocytes, lymph nodes cells and in ex vivo re-stimulated leucocytes (pooled splenocytes and lymph nodes cells) isolated at same days. To investigate the importance of Treg cells in IFN-α protection in AIA, Foxp3DTReGFP+mice were used, where Treg cells can be depleted transiently by administration of diptherin toxin. CFSE based suppression assay was used to assess the suppression by Treg cells isolated day 4, 10, 20 of AIA against proliferation of mBSA or anti-CD3 stimulated responder T cells (Tresp cells) isolated at same days. For adoptive transfer experiments, 250,000 Treg cells from IFN-α treated or untreated mice day 20 of AIA were intravenously injected to recipient pre-immunized mice without IFN-α treatment during the induction of arthritis. The importance of IFN-α signalling on T cells for the IFN-α protection was evaluated by using CD4-Cre+/- IFNAR flox/flox mice.ResultsProtective effects of IFN-α in AIA were associated with significant TGF-β dependent increase in Foxp3+ T cells in blood at day 4 and minor increase of Foxp3+T cells in spleen and lymph node cells. However IFN-α signalling in T cells is not required for IFN-α-protection. Upon ex vivo re-stimulation in presence of IFN-α with mBSA but not anti-CD3, the Treg cells numbers were increased in leucocytes isolated from day 4 and day 10 of AIA. Transient depletion of Treg cells during induction of arthritis (day 21) abolished IFN-α-protection however the protection was not affected when Treg cells are depleted during immunization phase (day 1 and day 7). Against mBSA-stimulated proliferation of Tresp cells, suppression by Treg cells isolated from day 10 and day 20 from IFN-α treated mice are significantly higher than Treg cells from untreated mice. Treg cells isolated from IFN-α or untreated mice at day 20 of AIA when transferred to pre-immunized untreated mice prevent the development of arthritis.ConclusionTreg cells are critically associated with IFN-α protective effects in AIA. IFN-α enhances TGF-β dependent early development of Treg cells and later IFN-α enhances their suppressive capacity against T cells proliferation in antigen specific manner during AIA.
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4.
  • Chenna Narendra, Sudeep, et al. (författare)
  • Local but Not Systemic Administration of Uridine Prevents Development of Antigen-Induced Arthritis
  • 2015
  • Ingår i: PLOS ONE. - : PUBLIC LIBRARY SCIENCE. - 1932-6203. ; 10:10, s. e0141863-
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective Uridine has earlier been show to down modulate inflammation in models of lung inflammation. The aim of this study was to evaluate the anti-inflammatory effect of uridine in arthritis. Methods Arthritis was induced by intra-articular injection of mBSA in the knee of NMRI mice preimmunized with mBSA. Uridine was either administered locally by direct injection into the knee joint or systemically. Systemic treatment included repeated injections or implantation of a pellet continuously releasing uridine during the entire experimental procedure. Anti-mBSA specific immune responses were determined by ELISA and cell proliferation and serum cytokine levels were determined by Luminex. Immunohistochemistry was used to identify cells, study expression of cytokines and adhesion molecules in the joint. Results Local administration of 25-100 mg/kg uridine at the time of arthritis onset clearly prevented development of joint inflammation. In contrast, systemic administration of uridine (max 1.5 mg uridine per day) did not prevent development of arthritis. Protection against arthritis by local administration of uridine did not affect the anti-mBSA specific immune response and did not prevent the rise in serum levels of pro-inflammatory cytokines associated with the triggering of arthritis. In contrast, local uridine treatment efficiently inhibited synovial expression of ICAM-1 and CD18, local cytokine production and recruitment of leukocytes to the synovium. Conclusion Local, but not systemic administration of uridine efficiently prevented development of antigen- induced arthritis. The protective effect did not involve alteration of systemic immunity to mBSA but clearly involved inhibition of synovial expression of adhesion molecules, decreased TNF and IL-6 production and prevention of leukocyte extravasation. Further, uridine is a small, inexpensive molecule and may thus be a new therapeutic option to treat joint inflammation in RA.
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5.
  • Chenna Narendra, Sudeep, et al. (författare)
  • Regulatory T-Cells Mediate IFN-alpha-Induced Resistance against Antigen-Induced Arthritis
  • 2018
  • Ingår i: Frontiers in Immunology. - : FRONTIERS MEDIA SA. - 1664-3224. ; 9
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective: CD4(+)FoxP3(+)CD25(+) regulatory T-cells (T-regs) are important for preventing tissue destruction. Here, we investigate the role of T-regs for protection against experimental arthritis by IFN-alpha. Methods: Arthritis was triggered by intra-articular injection of methylated bovine serum albumin (mBSA) in wild-type mice, Foxp3DTReGFP(+/-) mice [allowing selective depletion of T-regs by diphtheria toxin (DT)] and CD4-Cre(+/-) IFNA1R flox/flox mice (devoid of IFNAR signaling in T-cells) earlier immunized with mBSA, with or without treatment with IFN-alpha or the indoleamine 2,3-dioxygenase (IDO)-metabolite kynurenine. T-regs were depleted in DT-treated Foxp3DTReGFP(+/-) mice and enumerated by FoxP3 staining. Suppressive capacity of FACS-sorted CD25(+high)CD4(+) T-regs was tested in vivo by adoptive transfer and ex vivo in cocultures with antigen-stimulated CFSE-stained T-responder (CD25-CD4(+)) cells. IDO was inhibited by 1-methyl tryptophan. Results: Both control mice and mice devoid of IFNAR-signaling in T helper cells were protected from arthritis by IFN-alpha. Depletion of T-regs in the arthritis phase, but not at immunization, abolished the protective effect of IFN-alpha and kynurenine against arthritis. IFN-alpha increased the number of T-regs in ex vivo cultures upon antigen recall stimulation but not in naive cells. IFN-alpha also increased the suppressive capacity of T-regs against mBSA-induced T-responder cell proliferation ex vivo and against arthritis when adoptively transferred. The increased suppressive activity against proliferation conferred by IFN-alpha was clearly reduced by in vivo inhibition of IDO at immunization, which also abolished the protective effect of IFN-alpha against arthritis. Conclusion: By activating IDO during antigen sensitization, IFN-alpha activates T-regs, which prevent arthritis triggered by antigen rechallenge. This is one way by which IFN-alpha suppresses inflammation.
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6.
  • Chenna Narendra, Sudeep (författare)
  • Systemic and local regulation of experimental arthritis by IFN-α, dendritic cells and uridine
  • 2017
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • In this thesis, we have studied the immunological processes of joint inflammation that may be targets for future treatment of patients with arthritis. We focus on the immune-modulating properties of interferon-α (IFN-α) and uridine in experimental arthritis. The nucleoside uridine, which is regarded a safe treatment has anti-inflammatory properties notably by inhibiting tumor necrosis factor (TNF) release. Because the inflamed synovium in rheumatoid arthritis (RA) is characterised by pathogenic TNF-production, uridine could potentially be away to ameliorate arthritis. Systemic administration of uridine had no effect on antigeninduced arthritis (AIA), which is a T-cell dependent model where animals are immunized twice (sensitization) with bovine serum albumin (mBSA), before local triggering of arthritis by intra-articular antigen (mBSA) re-challenge. In contrast, intra-articular administration of uridine clearly down modulated development of AIA in a dose dependent manner and inhibited the expression of synovial adhesion molecules, influx of inflammatory leukocytes and synovial expression of TNF and interleukin 6, but did not affect systemic levels of proinflammatory cytokines or antigen-specific T-cell responses. Local administration of uridine may thus be a viable therapeutic option for treatment of arthritis in the future.Viral double-stranded deoxyribonucleic acid (dsRNA), a common nucleic acid found in most viruses, can be found in the joints of RA patients and local deposition of such viral dsRNA induces arthritis by activating IFN-α. Here we show that arthritis induced by dsRNA can be mediated by IFN-producing dendritic cells in the joint and this may thus explain why viral infections are sometimes associated with arthritis.Earlier, to study the effect of dsRNA and IFN-α in an arthritis model, that like RA, is dependent on adaptive immunity, dsRNA and IFN-α were administered individually during the development of AIA. Both molecules clearly protected against AIA in a type I IFN receptor-dependent manner but were only effective if administered in the sensitization phase of AIA. Here we show that the anti-inflammatory effect of IFN-α is critically dependent on signalling via transforming growth factor β (TGF-β) and the enzymatic activity of indoleamine 2,3 dioxygenase 1 (IDO). The IDO enzyme is produced by plasmacytoid DC and this cell type was critically required both during antigen sensitization and in the arthritis phase of AIA for the protective effect of IFN-α against AIA. In contrast, TGF-β and the enzymatic activity of IDO were only required during sensitization, which indicate that they are involved in initial steps of tolerogenic antigen sensitization. In this scenario, IFN- α first activates the enzymatic activity of IDO in pDC, which converts Tryptophan to Kynurenine, which thereafter activates TGF-β. Common for IDO-expressing pDC, Kyn and TGF-β is their ability to induce development of regulatory T cells (Tregs). We found that Tregs were crucial for IFN-α-mediated protection against AIA, but only in the arthritis phase. In line with this, adoptive transfer of Tregs isolated from IFN-α treated mice to recipient animals in the arthritis phase clearly protected against AIA. The numbers of Tregs were not significantly altered by IFN-α but IFN-α increased the suppressive capacity of Tregs against antigen-induced proliferation. This enhanced suppressive activity of Tregs in the arthritis phase was dependent on the earlier activated enzyme IDO1 during the sensitization phase of AIA. Thus, presence of IFN-α at the time of antigen sensitization activates the enzymatic activity of IDO, which generates Tregs with enhanced suppressive capacity that upon antigen re-challenge prevents inflammation. We have thus identified one example of how immune tolerance can be developed, that may be a future way to combat autoimmunity.
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7.
  • Kumar Jeengar, Manish, et al. (författare)
  • Local administration of 4-Thiouridine, a novel molecule with potent antiinflammatory properties, protects against experimental colitis and arthritis
  • 2020
  • Ingår i: International Immunopharmacology. - : ELSEVIER. - 1567-5769 .- 1878-1705. ; 85
  • Tidskriftsartikel (refereegranskat)abstract
    • Previous studies in a rat model of Sephadex induced lung inflammation showed that 4-Thiouridine (4SU), a thiol substituted nucleoside, was very effective in reducing edema, leukocyte influx and TNF levels in bronchoalvelolar lavage fluid. However, little is known about the factors and mechanisms underlying these effects. In the present study, we have used two separate mouse models of chronic inflammation, a model of dextran sulphate sodium (DSS) induced colitis and a model of antigen induced arthritis, to evaluate the anti-inflammatory effect of 4-thiouridine. We have analyzed a broad spectrum of inflammatory mediators in order to delineate the mechanisms behind a potential anti-inflammatory effect of 4SU. Colitis was induced in C57BL/6 mice by administration of 3.5% DSS in drinking water for 5 days and the potential anti-colitic effect of 4SU was assessed by monitoring the disease activity index (DAI), measurement of colon length and histopathological analysis of colon tissue. We analyzed tissue myeloperoxidase (MPO) activity, serum pro-inflammatory cytokines (IL-1 beta, IL-6 and TNF), mRNA and protein expression of pro-inflammatory cytokines, COX-2, and NF-kappa B activity in colitis tissue. Intracolonic administration of 4SU (5 mg/kg & 10 mg/kg.) significantly inhibited MPO activity and reduced the levels of pro-inflammatory cytokines (IL-1 beta, IL-6 and TNF) as well as COX-2. Further, NF-kappa B activation was also blocked by attenuating the phosphorylation of IkB kinase (IKK alpha/beta) in DSS-induced colitis tissues. Arthritis was induced by intra-articular injection of mBSA in the knee of NMRI mice pre-immunized with mBSA and 4SU was administered locally by direct injection into the knee joint. The antiarthritic potential of 4SU was calculated by histopathological scores and histochemical analysis of joint tissue. Further, immunohistochemistry was used to study inflammatory cell infiltration and expression of cytokines and adhesion molecules in the synovium. Local administration of 50-100 mg/kg 4SU at the time of arthritis onset clearly prevented development of joint inflammation and efficiently inhibited synovial expression of CD18, local cytokine production and recruitment of leukocytes to the synovium. Taken together, our data clearly demonstrates a potent anti-inflammatory effect of 4SU in two experimental models. In conclusion 4SU could be a new promising candidate for therapeutic modulation of chronic inflammatory diseases like ulcerative colitis and arthritis.
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8.
  • Narendra, Sudeep Chenna, et al. (författare)
  • Dendritic cells activated by double-stranded RNA induce arthritis via autocrine type I IFN signaling
  • 2014
  • Ingår i: Journal of Leukocyte Biology. - : Oxford University Press (OUP). - 0741-5400 .- 1938-3673. ; 95:4, s. 661-666
  • Tidskriftsartikel (refereegranskat)abstract
    • Type I IFN-dependent and -independent pathways regulate arthritis activated by dsRNA-stimulated DC. Viral dsRNA can be found at the site of inflammation in RA patients, and intra-articular injection of dsRNA induces arthritis by activating type I IFN signaling in mice. Further, DCs, a major source of IFN-, can be found in the synovium of RA patients. We therefore determined the occurrence of DCs in dsRNA-induced arthritis and their ability to induce arthritis. Here, we show, by immunohistochemistry, that cells expressing the pan-DC marker CD11c and the pDC marker 120G8 are present in the inflamed synovium in dsRNA-induced arthritis. Flt3L-generated and splenic DCs preactivated with dsRNA before intra-articular injection, but not mock-stimulated cells, clearly induced arthritis. Induction of arthritis was dependent on type I IFN signaling in the donor DCs, whereas IFNAR expression in the recipient was not required. Sorting of the Flt3L-DC population into cDCs (CD11c(+), PDCA-1(-)) and pDCs (CD11c(+), PDCA-1(+)) revealed that both subtypes were arthritogenic and produced type I IFN if treated with dsRNA. Taken together, these results demonstrate that viral nucleic acids can elicit arthritis by activating type I IFN signaling in DCs. Once triggered, autocrine type I IFN signaling in dsRNA-activated DCs is sufficient to propagate arthritis.
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9.
  • Prakash Chalise, Jaya, et al. (författare)
  • IDO1 and TGF-beta Mediate Protective Effects of IFN-alpha in Antigen-Induced Arthritis
  • 2016
  • Ingår i: Journal of Immunology. - : AMER ASSOC IMMUNOLOGISTS. - 0022-1767 .- 1550-6606. ; 197:8, s. 3142-3151
  • Tidskriftsartikel (refereegranskat)abstract
    • IFN-alpha prevents Ag-induced arthritis (AIA), and in this study we investigated the role of IDO1 and TGF-beta signaling for this anti-inflammatory property of IFN-alpha. Arthritis was induced by methylated BSA (mBSA) in mBSA-sensitized wild-type (WT), Ido1(-/-), or Ifnar(-/-) mice, treated or not with IFN-alpha or the IDO1 product kynurenine (Kyn). Enzymatic IDO1 activity, TGF-beta, and plasmacytoid dendritic cells (pDC) were neutralized by 1-methyltryptophan and Abs against TGF-beta and pDC, respectively. IDO1 expression was determined by RT-PCR, Western blot, and FACS, and enzymatic activity by HPLC. Proliferation was measured by H-3-thymidine incorporation and TGF-beta by RT-PCR and ELISA. WT but not Ido1(-/-) mice were protected from AIA by IFN-alpha, and Kyn, the main IDO1 product, also prevented AIA, both in WTand Ifnar(-/-) mice. Protective treatment with IFN-alpha increased the expression of IDO1 in pDC during AIA, and Ab-mediated depletion of pDC, either during mBSA sensitization or after triggering of arthritis, completely abrogated the protective effect of IFN-alpha. IFN-alpha treatment also increased the enzymatic IDO1 activity (Kyn/tryptophan ratio), which in turn activated production of TGF-beta. Neutralization of enzymatic IDO1 activity or TGF-beta signaling blocked the protective effect of IFN-alpha against AIA, but only during sensitization and not after triggering of arthritis. Likewise, inhibition of the IDO1 enzymatic activity in the sensitization phase, but not after triggering of arthritis, subdued the IFN-alpha-induced inhibition of mBSA-induced proliferation. In conclusion, presence of IFN-alpha at Ag sensitization activates an IDO1/TGF-beta-dependent anti-inflammatory program that upon antigenic rechallenge prevents inflammation via pDC.
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10.
  • Ying, Fei, et al. (författare)
  • Type I IFN protects against antigen-induced arthritis
  • 2011
  • Ingår i: European Journal of Immunology. - : John Wiley and Sons, Ltd. - 0014-2980 .- 1521-4141. ; 41:6, s. 1687-1695
  • Tidskriftsartikel (refereegranskat)abstract
    • Autoimmune diseases including rheumatoid arthritis (RA) involve immune reactions against specific antigens. The type I IFN system is suspected to promote autoimmunity in systemic lupus erythematosus, but may also dampen immune reactions in e. g. inflammatory bowel disease. This prompted us to investigate the role of type I IFN in antigen-induced arthritis (AIA). The importance of type I IFN in methylated (m) BSA-induced arthritis was studied by using mice deficient for the type I IFN receptor (IFNAR) and by administration of the IFN-alpha activator viral double-stranded (ds) RNA or recombinant IFN-alpha at antigen sensitization. In IFNAR knock-out mice, arthritis severity was significantly higher than in WT mice. Administration of dsRNA at antigen sensitization protected WT but not IFNAR KO mice from arthritis. Also, addition of recombinant IFN-alpha during the immunization, but not the induction phase of arthritis, almost abolished arthritis. Protection mediated by IFN-alpha was accompanied by delayed and decreased antigen-specific proliferative responses, including impaired lymph node recall responses after intra-articular antigenic challenge. In conclusion, we demonstrate that type I IFN can prevent joint inflammation by downregulating antigen-specific cellular immunity.
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