Down-Regulation of Th2 Responses by Brucella abortus, a Strong Th1 Stimulus, Correlates with Alterations in the B7.2-CD28 Pathway

ABSTRACT Down-regulation of the Th2-like response induced by ovalbumin-alum (OVA/alum) immunization by heat-killed Brucella abortus was not reversed by anti-IL-12 antibody treatment or in gamma interferon (IFN-γ) knockout mice, suggesting that induction of Th1 cytokines was not the only mechanism involved in the B. abortus-mediated inhibition of the Th2 response to OVA/alum. The focus of this study was to determine whether an alternative pathway involves alteration in expression of costimulatory molecules. First we show that the Th2-like response to OVA/alum is dependent on B7.2 interaction with ligand since it can be abrogated by anti-B7.2 treatment. Expression of costimulatory molecules was then studied in mice immunized with OVA/alum in the absence or presence of B. abortus. B7.2, but not B7.1, was up-regulated on mouse non-T and T cells following immunization withB. abortus. Surprisingly, B. abortus induced down-regulation of CD28 and up-regulation of B7.2 on murine CD4+ and CD8+ T cells. These effects on T cells were maximal for CD28 and B7.2 at 40 to 48 h and were not dependent on interleukin-12 (IL-12) or IFN-γ. On the basis of these results, we propose that the IL-12/IFN-γ-independent inhibition of Th2 responses to OVA/alum is secondary to the effects of B. abortus on expression of costimulatory molecules on T cells. We suggest that down-regulation of CD28 following activation inhibits subsequent differentiation of Th0 into Th2 cells. In addition, decreased expression of CD28 and increased expression of B7.2 on T cells would favor B7.2 interaction with CTLA-4 on T cells, and this could provide a negative signal to developing Th2 cells.

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Ontogeny of Th1 Memory Responses against a Brucella abortus Conjugate

Infection and Immunity ◽

10.1128/iai.69.9.5417-5422.2001 ◽

2001 ◽

Vol 69 (9) ◽

pp. 5417-5422 ◽

Cited By ~ 9

Author(s):

Orit Scharf ◽

Inna Agranovich ◽

Katherine Lee ◽

Nancy L. Eller ◽

Lily Levy ◽

...

Keyword(s):

Brucella Abortus ◽

Immunoglobulin E ◽

Single Injection ◽

Allergen Challenge ◽

Th2 Cells ◽

Interleukin 12 ◽

Th2 Response ◽

Immune Development ◽

Ifn Γ ◽

Old Mice

ABSTRACT Protective immune responses to intracellular pathogens such asBrucella abortus are characteristically Th1-like. Recently we demonstrated that heat-killed B. abortus (HKBa), a strong Th1 stimulus, conjugated to ovalbumin (HKBA-OVA), but notB. abortus alone, can alter the antigen-specific cytokine profile from Th2- to Th1-like. In this report we study the ability of a single injection of B. abortus to switch a Th2 to a Th1 response in immature mice. One-day- and 1-week-old mice were given a single injection of B. abortus in the absence or presence of OVA, and at maturity mice were challenged with an allergenic preparation, OVA with alum (OVA-A). B. abortus given without OVA did not diminish the subsequent Th2 response in either age group. In contrast, mice receiving a single injection of B. abortus-OVA at the age of 1 week, but not those injected at the age of 1 day, had reversal of the ratio of OVA-specific Th1 to Th2 cells and decreased immunoglobulin E levels after allergen challenge as adults. Within 6 h both 1-day- and 1-week-old mice expressed interleukin-12 p40 mRNA following either B. abortus orB. abortus-OVA administration. However, only the 1-week-old mice exhibited increased expression of gamma interferon (IFN-γ) mRNA. The absence of the early IFN-γ response in 1-day-old mice may explain their inability to generate a Th1 memory response. These results suggest that at early stages of immune development, responses to intracellular bacteria may be Th2- rather than Th1-like. Furthermore, they suggest that the first encounter with antigen evokes either a Th1- or a Th2-like response which becomes imprinted, so that subsequent memory responses conform to the original Th bias. This has implications for protection against infectious agents and development of allergic responses.

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Th2-driven, allergen-induced airway inflammation is reduced after treatment with anti–Tim-3 antibody in vivo

Journal of Experimental Medicine ◽

10.1084/jem.20062093 ◽

2007 ◽

Vol 204 (6) ◽

pp. 1289-1294 ◽

Cited By ~ 41

Author(s):

Jennifer Kearley ◽

Sarah J. McMillan ◽

Clare M. Lloyd

Keyword(s):

Pulmonary Inflammation ◽

Allergen Challenge ◽

Airway Hyperreactivity ◽

Th2 Cells ◽

Antibody Treatment ◽

Th2 Response ◽

Th2 Cytokine ◽

Cytokine Levels ◽

Ifn Γ

T cell immunoglobulin and mucin domain–containing molecule-3 (Tim-3) is a surface molecule that is preferentially expressed on activated Th1 cells in comparison to Th2 cells. Blockade of Tim-3 has been shown to enhance Th1-driven pathology in vivo, suggesting that blockade of Tim-3 may improve the development of Th2-associated responses such as allergy. To examine the effects of Tim-3 blockade on the Th2 response in vivo, we administered anti–Tim-3 antibody during pulmonary inflammation induced by transfer of ovalbumin (OVA)-reactive Th2 cells, and subsequent aerosol challenge with OVA. In this model, anti–Tim-3 antibody treatment before each airway challenge significantly reduced airway hyperreactivity, with a concomitant decrease in eosinophils and Th2 cells in the lung. We examined Th1 and Th2 cytokine levels in the lung after allergen challenge and found that pulmonary expression of the Th2 cytokine IL-5 was significantly reduced, whereas IFN-γ levels were significantly increased by anti–Tim-3 antibody treatment. Thus, blocking Tim-3 function has a beneficial effect during pulmonary inflammation by skewing the Th2 response toward that of a Th1 type, suggesting an important role for Tim-3 in the regulation of allergic disease.

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T Helper Type 2 Cell Differentiation Occurs in the Presence of Interleukin 12 Receptor β2 Chain Expression and Signaling

Journal of Experimental Medicine ◽

10.1084/jem.191.5.847 ◽

2000 ◽

Vol 191 (5) ◽

pp. 847-858 ◽

Cited By ~ 53

Author(s):

Ryuta Nishikomori ◽

Rolf O. Ehrhardt ◽

Warren Strober

Keyword(s):

T Cells ◽

Cd4 T Cells ◽

Th2 Cells ◽

Interleukin 12 ◽

Th1 Cells ◽

T Helper ◽

Ifn Γ ◽

Helper Type

The differentiation of CD4+ T cells into T helper type 1 (Th1) cells is driven by interleukin (IL)-12 through the IL-12 receptor β2 (IL-12Rβ2) chain, whereas differentiation into Th2 cells is driven by IL-4, which downregulates IL-12Rβ2 chain. We reexamined such differentiation using IL-12Rβ2 chain transgenic mice. We found that CD4+ T cells from such mice were able to differentiate into Th2 cells when primed with IL-4 or IL-4 plus IL-12. In the latter case, the presence of IL-4 suppressed interferon (IFN)-γ production 10–100-fold compared with cells cultured in IL-12 alone. Finally, in studies of the ability of IL-12 to convert Th2 cells bearing a competent IL-12R to the Th1 cells, we showed that: (a) T cells bearing the IL-12Rβ2 chain transgene and primed under Th2 conditions could not be converted to Th1 cells by repeated restimulation under Th1 conditions; and (b) established Th2 clones transfected with the IL-12Rβ2 chain construct continued to produce IL-4 when cultured with IL-12. These studies show that IL-4–driven Th2 differentiation can occur in the presence of persistent IL-12 signaling and that IL-4 inhibits IFN-γ production under these circumstances. They also show that established Th2 cells cannot be converted to Th1 cells via IL-12 signaling.

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Signaling through the T1/ST2 Molecule Is Not Necessary for Th2 Differentiation but Is Important for the Regulation of Type 1 Responses in Nonhealing Leishmaniamajor Infection

Infection and Immunity ◽

10.1128/iai.71.4.1961-1971.2003 ◽

2003 ◽

Vol 71 (4) ◽

pp. 1961-1971 ◽

Cited By ~ 24

Author(s):

P. Kropf ◽

S. Herath ◽

R. Klemenz ◽

I. Müller

Keyword(s):

T Cells ◽

Fusion Protein ◽

Cytokine Profile ◽

Th2 Cells ◽

Interleukin 12 ◽

Th2 Response ◽

Th1 Response ◽

Fc Fusion Protein

ABSTRACT T1/ST2 is a stable cell surface marker selectively expressed on type 2 T helper (Th2) effector cells. Since nonhealing Leishmania major infections in susceptible BALB/c mice have been ascribed to a polarized Th2 response, we used an anti-T1/ST2 monoclonal antibody (MAb) or a T1-Fc fusion protein to investigate the role of CD4+ T1/ST2+ Th2 cells in experimental leishmaniasis. We show that interfering with T1/ST2 signaling had no effect on lesion development or parasite replication; however, it induced a significantly higher type 1 response and an enhanced capacity of CD4+ T cells to respond to interleukin 12 (IL-12). Surprisingly, even in the presence of an elevated Th1 response, the production of antigen-specific type 2 cytokines was not altered in the group of mice treated with the anti-T1/ST2 MAb or the T1-Fc fusion protein. To characterize further this Th2 response, we assessed the cytokine profile of CD4+ T cells and found that interfering with T1/ST2 signaling did not alter the cytokine profile of CD4+ T1/ST2+ T cells. These results show that T1/ST2 signaling is not necessary for the differentiation of naive CD4+ T cells into antigen-specific CD4+ T1/ST2+ Th2 cells. In addition to CD4+ T1/ST2+ T cells, we detected another subpopulation of CD4+ Th2 cells, negative for the expression of T1/ST2, that could differentiate in vivo in response to L. major infection. Taken together, our results suggest that CD4+ T1/ST2+ Th2 cells but not CD4+ T1/ST2− Th2 cells can downregulate the Th1 response during the course of a nonhealing L. major infection through a mechanism that is independent of IL-4 or IL-10.

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Altered Interleukin-12 Responsiveness in Th1 and Th2 Cells Is Associated With the Differential Activation of STAT5 and STAT1

Blood ◽

10.1182/blood.v91.4.1341 ◽

1998 ◽

Vol 91 (4) ◽

pp. 1341-1354 ◽

Cited By ~ 50

Author(s):

Jared A. Gollob ◽

Erin A. Murphy ◽

Sudipta Mahajan ◽

Claudia P. Schnipper ◽

Jerome Ritz ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Dna Binding ◽

Tyrosine Phosphorylation ◽

T Cell Activation ◽

Th2 Cells ◽

Interleukin 12 ◽

Th1 Cells ◽

Functional Responses ◽

Ifn Γ

Abstract T-cell activation in response to interleukin-12 (IL-12) is mediated through signaling events that include the tyrosine phosphorylation of STAT4. IL-12 responsiveness and the ability of IL-12 to activate STAT4 is different in T cells induced to differentiate into a Th1 or Th2 phenotype. In this report, we show that STAT5, STAT1α, and STAT1β, in addition to STAT4, are tyrosine phosphorylated in response to IL-12 in phytohemagglutinin (PHA)-activated human T cells. To understand how the activation of these STATs contributes to T-cell IL-12 responsiveness, we analyzed the IL-12–induced activation of STAT5 and STAT1 in T cells stimulated to undergo Th1 or Th2 differentiation. The IL-12–induced tyrosine phosphorylation of STAT5 and STAT1, but not STAT4, is augmented in T cells activated into Th1 cells with PHA + interferon-γ (IFN-γ) compared with T cells activated with PHA alone. STAT5 DNA binding induced by IL-12 is also augmented in T cells activated with PHA + IFN-γ compared with T cells activated with PHA alone, whereas STAT4 DNA binding is not increased. In contrast, the IL-12–induced activation of these STATs is inhibited in T cells activated into Th2 cells with PHA + IL-4. The enhancement of IL-12 signaling by IFN-γ is not a direct effect of IFN-γ on T cells, but rather is mediated by IL-12 that is produced by antigen-presenting cells in response to IFN-γ. This positive autoregulatory effect of IL-12 on the activation of select STATs correlates with an increase in T-cell IFN-γ production in response to IL-12. These findings suggest that the activation of STAT5 and STAT1 may augment select STAT4-dependent functional responses to IL-12 in Th1 cells.

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Specific down-regulation of interleukin-12 signaling through induction of phospho-STAT4 protein degradation

Blood ◽

10.1182/blood.v97.12.3860 ◽

2001 ◽

Vol 97 (12) ◽

pp. 3860-3866 ◽

Cited By ~ 26

Author(s):

Kathy S. Wang ◽

Emmanuel Zorn ◽

Jerome Ritz

Keyword(s):

Clinical Trials ◽

T Cells ◽

Messenger Rna ◽

Critical Role ◽

Repeated Administration ◽

Interleukin 12 ◽

Antitumor Effects ◽

Down Regulation ◽

Human T Cells ◽

Ifn Γ

Interleukin-12 (IL-12) plays a critical role in modulating the function of T lymphocytes and natural killer cells. IL-12 has potent antitumor effects in animal models, mediated primarily by its ability to enhance cytolytic activity and secretion of interferon-γ (IFN-γ). Unfortunately, the antitumor effect of IL-12 has not been demonstrated in clinical trials. Repeated administration of IL-12 in humans results in decreasing levels of IFN-γ secretion. To understand the mechanism underlying this loss of responsiveness, the effect of IL-12 on its own signaling in activated human T cells was examined. These experiments demonstrate that the level of the signal transducer and activator of transcription 4 (STAT4) protein, a critical IL-12 signaling component, is dramatically decreased 24 hours after IL-12 stimulation, whereas levels of STAT4 messenger RNA are not affected. The decrease of STAT4 protein appears to be due to specific degradation of phospho-STAT4, possibly through the proteasome degradation pathway. Decreased levels of STAT4 protein lead to decreased STAT4 DNA-binding activity and reduced proliferation and secretion of IFN-γ. This down-regulation of STAT4 is specific for IL-12 signaling, presumably owing to the prolonged activation of STAT4 induced by IL-12. IFN-α stimulation, which leads to transient phosphorylation of STAT4, does not reduce the level of STAT4 protein. These findings provide new insights into the regulation of IL-12 signaling in human T cells, where IL-12 promotes TH1 responses, but persistent IL-12 stimulation may also limit this response. The cellular depletion of STAT4 following prolonged IL-12 stimulation may also explain the loss of responsiveness following the repeated administration of IL-12 in clinical trials.

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SERPINB10 contributes to asthma by inhibiting the apoptosis of allergenic Th2 cells

Respiratory Research ◽

10.1186/s12931-021-01757-1 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Yuqing Mo ◽

Ling Ye ◽

Hui Cai ◽

Guiping Zhu ◽

Jian Wang ◽

...

Keyword(s):

T Cells ◽

Allergic Asthma ◽

Cd4 T Cells ◽

Quantitative Polymerase Chain Reaction ◽

Allergic Inflammation ◽

Specific Ige ◽

Th2 Cells ◽

Th1 Cells ◽

Th2 Response ◽

Th1 And Th2

Abstract Background Serine peptidase inhibitor, clade B, member 10 (SERPINB10) contributes to allergic inflammation in asthma. However, its role in the T-helper type 2 (Th2) response of allergic asthma is not known. The goal of this study was to unveil the function of SERPINB10 in the Th2 response of allergic asthma and the mechanism by which SERPINB10 affects the viability of Th2 cells. Methods Th2 cytokines and serum levels of house dust mite (HDM)-specific IgE in bronchoalveolar lavage fluid were examined by ELISA in an HDM-induced asthma model. The number and apoptosis of Th1 and Th2 cells in mouse lungs were measured by flow cytometry. Naïve CD4 T cells from patients with asthma were cultured under appropriate polarizing conditions to generate Th1 and Th2 cells. SERPINB10 expression in polarized Th1 and Th2 cells was quantified by real-time reverse transcription-quantitative polymerase chain reaction. SERPINB10 expression was knocked down in human CD4 T cells with lentivirus. Results Knockdown of SERPINB10 expression significantly diminished HDM-induced Th2 cytokine secretion and level of HDM-specific IgE. After HDM exposure, SERPINB10-knockdown mice had diminished numbers of Th2 cells, but similar numbers of Th1 cells, compared with those in negative-control mice. Th2 cells of SERPINB10-knockdown mice were more susceptible to apoptosis than that of control mice. Stimulating T-cell receptors (TCRs) with anti-CD3 antibody caused upregulation of SERPINB10 expression in polarized Th2 cells, but not polarized Th1 cells. Knockdown of SERPINB10 expression resulted in fewer numbers and greater apoptosis of polarized Th2 cells. Conclusion Our results suggest that SERPINB10 may contribute to allergic inflammation and the Th2 response of asthma by inhibiting the apoptosis of Th2 cells.

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Interleukin 12 induces stable priming for interferon gamma (IFN-gamma) production during differentiation of human T helper (Th) cells and transient IFN-gamma production in established Th2 cell clones.

Journal of Experimental Medicine ◽

10.1084/jem.179.4.1273 ◽

1994 ◽

Vol 179 (4) ◽

pp. 1273-1283 ◽

Cited By ~ 269

Author(s):

R Manetti ◽

F Gerosa ◽

M G Giudizi ◽

R Biagiotti ◽

P Parronchi ◽

...

Keyword(s):

T Cells ◽

Interferon Gamma ◽

Specific Antigen ◽

Th2 Cells ◽

Interleukin 12 ◽

T Helper ◽

Ifn Gamma ◽

Selection Of

Interleukin 12 (IL-12) facilitates the generation of a T helper type 1 (Th1) response, with high interferon gamma (IFN-gamma) production, while inhibiting the generation of IL-4-producing Th2 cells in polyclonal cultures of both human and murine T cells and in vivo in the mouse. In this study, we analyzed the effect of IL-12, present during cloning of human T cells, on the cytokine profile of the clones. The culture system used allows growth of clones from virtually every T cell, and thus excludes the possibility that selection of precommitted Th cell precursors plays a role in determining characteristics of the clones. IL-12 present during the cloning procedures endowed both CD4+ and CD8+ clones with the ability to produce IFN-gamma at levels severalfold higher than those observed in clones generated in the absence of IL-12. This priming was stable because the high levels of IFN-gamma production were maintained when the clones were cultured in the absence of IL-12 for 11 d. The CD4+ and some of the CD8+ clones produced variable amounts of IL-4. Unlike IFN-gamma, IL-4 production was not significantly different in clones generated in the presence or absence of IL-12. These data suggest that IL-12 primes the clone progenitors, inducing their differentiation to high IFN-gamma-producing clones. The suppression of IL-4-producing cells observed in polyclonally generated T cells in vivo and in vitro in the presence of IL-12 is not observed in this clonal model, suggesting that the suppression depends more on positive selection of non-IL-4-producing cells than on differentiation of individual clones. However, antigen-specific established Th2 clones that were unable to produce IFN-gamma with any other inducer did produce IFN-gamma at low but significant levels when stimulated with IL-12 in combination with specific antigen or insoluble anti-CD3 antibodies. This induction of IFN-gamma gene expression was transient, because culture of the established clones with IL-12 for up to 1 wk did not convert them into IFN-gamma producers when stimulated in the absence of IL-12. These results suggest that Th clones respond to IL-12 treatment either with a stable priming for IFN-gamma production or with only a transient low level expression of the IFN-gamma gene, depending on their stage of differentiation.

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Morin Promotes the Production of Th2 Cytokine by Modulating Bone Marrow-Derived Dendritic Cells

The American Journal of Chinese Medicine ◽

10.1142/s0192415x06004193 ◽

2006 ◽

Vol 34 (04) ◽

pp. 667-684 ◽

Cited By ~ 10

Author(s):

Chia-Yang Li ◽

Jau-Ling Suen ◽

Bor-Luen Chiang ◽

Pei-Dawn Lee Chao ◽

Shih-Hua Fang

Keyword(s):

Bone Marrow ◽

T Cells ◽

Dendritic Cells ◽

Interleukin 12 ◽

Th2 Response ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Th Differentiation ◽

Th1 And Th2 Responses

Our previous studies had reported that morin decreased the interleukin-12 (IL-12) and tumor necrosis factor-alpha (TNF-α) production in lipopolysaccharide (LPS)-activated macrophages, suggesting that morin may promote helper T type 2 (Th2) response in vivo. Dendritic cells (DCs) are the most potent antigen presenting cells and known to play a major role in the differentiation of helper T type 1 (Th1) and Th2 responses. This study aimed to reveal whether morin is able to control the Th differentiation through modulating the maturation and functions of DCs. Bone marrow-derived dendritic cells (BM-DCs) were incubated with various concentrations of morin and their characteristics were studied. The results indicated that morin significantly affects the phenotype and cytokine expression of BM-DCs. Morin reduced the production of IL-12 and TNF-α in BM-DCs, in response to LPS stimulation. In addition, the proliferative response of stimulated alloreactive T cells was significantly decreased by morin in BM-DCs. Furthermore, allogeneic T cells secreted higher IL-4 and lower IFN-γ in response to morin in BM-DCs. In conclusion, these results suggested that morin favors Th2 cell differentiation through modulating the maturation and function of BM-DCs.

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Interleukin-12 Is the Optimum Cytokine To Expand Human Th17 Cells In Vitro

Clinical and Vaccine Immunology ◽

10.1128/cvi.00022-09 ◽

2009 ◽

Vol 16 (6) ◽

pp. 798-805 ◽

Cited By ~ 6

Author(s):

Soad Nady ◽

James Ignatz-Hoover ◽

Mohamed T. Shata

Keyword(s):

T Cells ◽

Peripheral Blood ◽

Th17 Cells ◽

Interleukin 12 ◽

Interleukin 17 ◽

Functional Evaluation ◽

Optimum Conditions ◽

T Helper ◽

Ifn Γ

ABSTRACT Recently, a new lineage of CD4+ T cells in humans and in mice has been reported. This T helper cell secretes interleukin-17 (IL-17) and has been defined as T helper 17 (Th17). Th17 cells express the IL-23 receptor (IL-23R) and play an important pathogenic role in different inflammatory conditions. In this study, our aim was to characterize the optimum conditions for isolation and propagation of human peripheral blood Th17 cells in vitro and the optimum conditions for isolation of Th17 clones. To isolate Th17 cells, two steps were taken. Initially, we negatively isolated CD4+ T cells from peripheral blood mononuclear cells of a normal human blood donor. Then, we isolated the IL-23R+ cells from the CD4+ T cells. Functional studies revealed that CD4+ IL-23R+ cells could be stimulated ex vivo with anti-CD3/CD28 to secrete both IL-17 and gamma interferon (IFN-γ). Furthermore, we expanded the CD4+ IL-23R+ cells for 1 week in the presence of anti-CD3/CD28, irradiated autologous feeder cells, and different cytokines. Our data indicate that cytokine treatment increased the number of propagated cells 14- to 99-fold. Functional evaluation of the expanded number of CD4+ IL-23R+ cells in the presence of different cytokines with anti-CD3/CD28 revealed that all cytokines used (IL-2, IL-7, IL-12, IL-15, and IL-23) increased the amount of IFN-γ secreted by IL-23R+ CD4+ cells at different levels. Our results indicate that IL-7 plus IL-12 was the optimum combination of cytokines for the expansion of IL-23R+ CD4+ cells and the secretion of IFN-γ, while IL-12 preferentially stimulated these cells to secrete predominately IL-17.

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