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Antigen-specific signaling by a soluble, dimeric peptide/major histocompatibility complex class II/Fc chimera leading to T helper cell type 2 differentiation.

Casares S, Zong CS, Radu DL, Miller A, Bona CA, Brumeanu TD - J. Exp. Med. (1999)

Bottom Line: Interaction between a T cell receptor (TCR) and various ligands, i.e. , anti-TCR antibodies, superantigens, peptides, or altered peptide ligands in the context of major histocompatibility complex (MHC) molecules can trigger different T helper cell (Th) effector functions.Polarization of cognate T cells toward the Th2 response occurred upon interaction of soluble DEF with TCR and CD4 molecules followed by early activation of p56(lck) and ZAP-70 tyrosine kinases, and negative signaling of the signal transducer and activator of transcription (STAT)4 pathway of Th1 differentiation.DEF-like molecules may provide a new tool to study the mechanisms of signaling toward Th2 differentiation and may also provide a potential immunotherapeutic approach to modulate autoreactive T cells toward protective Th2 immune responses.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029, USA.

ABSTRACT
Interaction between a T cell receptor (TCR) and various ligands, i.e. , anti-TCR antibodies, superantigens, peptides, or altered peptide ligands in the context of major histocompatibility complex (MHC) molecules can trigger different T helper cell (Th) effector functions. Herein, we studied the T cell response induced by a soluble, dimeric peptide/MHC class II chimera, namely hemagglutinin (HA)110-120/I-E(d)alphabeta/Fcgamma2a (DEF). We have previously demonstrated that the soluble DEF molecule binds stably and specifically to HA110-120-specific TCRs expressed by a T cell hybridoma. Administration of DEF in vivo induced differentiation of resting and activated peptide-specific T cells toward a Th2 response, as indicated by the increase of interleukin (IL)-4, IL-10, and specific immunoglobulin (Ig)G1 antibodies and decrease of IL-2, specific IgG2a antibodies, and cytotoxic T lymphocyte activity. In contrast to HA110-120 peptide presented by the DEF molecule to T cells, the nominal synthetic peptide induced a predominant Th1 response, and the PR8 virus-derived HA110-120 peptides induced a mixed Th1/Th2 response. Independent of antigen processing, soluble DEF was almost 2 logs more potent in stimulating cognate T cells than the nominal peptide. Polarization of cognate T cells toward the Th2 response occurred upon interaction of soluble DEF with TCR and CD4 molecules followed by early activation of p56(lck) and ZAP-70 tyrosine kinases, and negative signaling of the signal transducer and activator of transcription (STAT)4 pathway of Th1 differentiation. DEF-like molecules may provide a new tool to study the mechanisms of signaling toward Th2 differentiation and may also provide a potential immunotherapeutic approach to modulate autoreactive T cells toward protective Th2 immune responses.

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Effect of DEF on CTL and Ab responses. (A) NP147-154–specific CTL activity from mice immunized with live PR8 influenza virus and treated or untreated with DEF on days 7, 8, and 9 after immunization. Spleen cells collected on day 10 after immunization were stimulated in vitro for 5 d with NP147-154 peptide, and CTL activity was measured against P18 target cells coated with NP147-154 synthetic peptide. The percentage of cytotoxicity was determined in four mice and corresponds to the mean of triplicate samples (cpm) ± SD. (B) IgG2a and IgG1 anti-PR8 Ab titers in BALB/c mice previously immunized with live influenza PR8 virus and then injected three times with 130 μg of DEF or PBS on days 7, 8, and 9 after immunization. Values represent the mean cpm measured in triplicate blood samples ± SD collected from individual mice on days 0, 7, and 14 after immunization.
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Figure 3: Effect of DEF on CTL and Ab responses. (A) NP147-154–specific CTL activity from mice immunized with live PR8 influenza virus and treated or untreated with DEF on days 7, 8, and 9 after immunization. Spleen cells collected on day 10 after immunization were stimulated in vitro for 5 d with NP147-154 peptide, and CTL activity was measured against P18 target cells coated with NP147-154 synthetic peptide. The percentage of cytotoxicity was determined in four mice and corresponds to the mean of triplicate samples (cpm) ± SD. (B) IgG2a and IgG1 anti-PR8 Ab titers in BALB/c mice previously immunized with live influenza PR8 virus and then injected three times with 130 μg of DEF or PBS on days 7, 8, and 9 after immunization. Values represent the mean cpm measured in triplicate blood samples ± SD collected from individual mice on days 0, 7, and 14 after immunization.

Mentions: The recruitment and differentiation of CD8 T cells depends greatly on the availability of cytokines secreted by CD4 Th1 cells, particularly IL-2. We thus investigated the extent to which DEF-induced Th2 response in vivo may affect the cytolytic function of CD8 T cells. BALB/c mice immunized with live PR8 virus and then treated with DEF showed a 40% reduction of CTL activity against target cells coated with NP147-154 peptide (Fig. 3 A). NP147-154 is a dominant CD8 T cell epitope of the nucleoprotein of influenza virus A/PR/834 in H-2d mice 23. Reduced CTL activity was correlated with a double bystander effect: IL-2 deprivation and increase of IL-4 production. Th1-derived IL-2 is the major growth factor required for differentiation and activation of CD8 T cells 27. Indeed, we previously found that depletion of CD4 T cells in naive TCR-HA Tg mice resulted in lack of differentiation of CTLs 28. Increase of IL-4 after DEF treatment could also deprive CD8 T cells of IL-2, as it is known that IL-4 and IL-10 are potent suppressors of IL-2 synthesis 29.


Antigen-specific signaling by a soluble, dimeric peptide/major histocompatibility complex class II/Fc chimera leading to T helper cell type 2 differentiation.

Casares S, Zong CS, Radu DL, Miller A, Bona CA, Brumeanu TD - J. Exp. Med. (1999)

Effect of DEF on CTL and Ab responses. (A) NP147-154–specific CTL activity from mice immunized with live PR8 influenza virus and treated or untreated with DEF on days 7, 8, and 9 after immunization. Spleen cells collected on day 10 after immunization were stimulated in vitro for 5 d with NP147-154 peptide, and CTL activity was measured against P18 target cells coated with NP147-154 synthetic peptide. The percentage of cytotoxicity was determined in four mice and corresponds to the mean of triplicate samples (cpm) ± SD. (B) IgG2a and IgG1 anti-PR8 Ab titers in BALB/c mice previously immunized with live influenza PR8 virus and then injected three times with 130 μg of DEF or PBS on days 7, 8, and 9 after immunization. Values represent the mean cpm measured in triplicate blood samples ± SD collected from individual mice on days 0, 7, and 14 after immunization.
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Related In: Results  -  Collection

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Figure 3: Effect of DEF on CTL and Ab responses. (A) NP147-154–specific CTL activity from mice immunized with live PR8 influenza virus and treated or untreated with DEF on days 7, 8, and 9 after immunization. Spleen cells collected on day 10 after immunization were stimulated in vitro for 5 d with NP147-154 peptide, and CTL activity was measured against P18 target cells coated with NP147-154 synthetic peptide. The percentage of cytotoxicity was determined in four mice and corresponds to the mean of triplicate samples (cpm) ± SD. (B) IgG2a and IgG1 anti-PR8 Ab titers in BALB/c mice previously immunized with live influenza PR8 virus and then injected three times with 130 μg of DEF or PBS on days 7, 8, and 9 after immunization. Values represent the mean cpm measured in triplicate blood samples ± SD collected from individual mice on days 0, 7, and 14 after immunization.
Mentions: The recruitment and differentiation of CD8 T cells depends greatly on the availability of cytokines secreted by CD4 Th1 cells, particularly IL-2. We thus investigated the extent to which DEF-induced Th2 response in vivo may affect the cytolytic function of CD8 T cells. BALB/c mice immunized with live PR8 virus and then treated with DEF showed a 40% reduction of CTL activity against target cells coated with NP147-154 peptide (Fig. 3 A). NP147-154 is a dominant CD8 T cell epitope of the nucleoprotein of influenza virus A/PR/834 in H-2d mice 23. Reduced CTL activity was correlated with a double bystander effect: IL-2 deprivation and increase of IL-4 production. Th1-derived IL-2 is the major growth factor required for differentiation and activation of CD8 T cells 27. Indeed, we previously found that depletion of CD4 T cells in naive TCR-HA Tg mice resulted in lack of differentiation of CTLs 28. Increase of IL-4 after DEF treatment could also deprive CD8 T cells of IL-2, as it is known that IL-4 and IL-10 are potent suppressors of IL-2 synthesis 29.

Bottom Line: Interaction between a T cell receptor (TCR) and various ligands, i.e. , anti-TCR antibodies, superantigens, peptides, or altered peptide ligands in the context of major histocompatibility complex (MHC) molecules can trigger different T helper cell (Th) effector functions.Polarization of cognate T cells toward the Th2 response occurred upon interaction of soluble DEF with TCR and CD4 molecules followed by early activation of p56(lck) and ZAP-70 tyrosine kinases, and negative signaling of the signal transducer and activator of transcription (STAT)4 pathway of Th1 differentiation.DEF-like molecules may provide a new tool to study the mechanisms of signaling toward Th2 differentiation and may also provide a potential immunotherapeutic approach to modulate autoreactive T cells toward protective Th2 immune responses.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029, USA.

ABSTRACT
Interaction between a T cell receptor (TCR) and various ligands, i.e. , anti-TCR antibodies, superantigens, peptides, or altered peptide ligands in the context of major histocompatibility complex (MHC) molecules can trigger different T helper cell (Th) effector functions. Herein, we studied the T cell response induced by a soluble, dimeric peptide/MHC class II chimera, namely hemagglutinin (HA)110-120/I-E(d)alphabeta/Fcgamma2a (DEF). We have previously demonstrated that the soluble DEF molecule binds stably and specifically to HA110-120-specific TCRs expressed by a T cell hybridoma. Administration of DEF in vivo induced differentiation of resting and activated peptide-specific T cells toward a Th2 response, as indicated by the increase of interleukin (IL)-4, IL-10, and specific immunoglobulin (Ig)G1 antibodies and decrease of IL-2, specific IgG2a antibodies, and cytotoxic T lymphocyte activity. In contrast to HA110-120 peptide presented by the DEF molecule to T cells, the nominal synthetic peptide induced a predominant Th1 response, and the PR8 virus-derived HA110-120 peptides induced a mixed Th1/Th2 response. Independent of antigen processing, soluble DEF was almost 2 logs more potent in stimulating cognate T cells than the nominal peptide. Polarization of cognate T cells toward the Th2 response occurred upon interaction of soluble DEF with TCR and CD4 molecules followed by early activation of p56(lck) and ZAP-70 tyrosine kinases, and negative signaling of the signal transducer and activator of transcription (STAT)4 pathway of Th1 differentiation. DEF-like molecules may provide a new tool to study the mechanisms of signaling toward Th2 differentiation and may also provide a potential immunotherapeutic approach to modulate autoreactive T cells toward protective Th2 immune responses.

Show MeSH
Related in: MedlinePlus