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T cell-NF-κB activation is required for tumor control in vivo.

Barnes SE, Wang Y, Chen L, Molinero LL, Gajewski TF, Evaristo C, Alegre ML - J Immunother Cancer (2015)

Bottom Line: However, it is not clear if this is causal for an inability to reject transformed cells, or if it is a consequence of tumor growth.Tumor antigen-specific T cell-IFN-γ and TNF-α production, as well as cytotoxic ability, were all reduced in mice with impaired T cell-NF-κB, suggesting an important role for this transcription factor in the effector differentiation of tumor-specific effector T cells.Maintaining or enhancing T cell-NF-κB activity may be a promising avenue for anti-tumor immunotherapy.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, The University of Chicago, 924 E. 57th St. JFK-R312, Chicago, IL 60637 USA.

ABSTRACT

Background: T cells have the capacity to eliminate tumors but the signaling pathways by which they do so are incompletely understood. T cell priming requires activation of the transcription factors AP-1, NFAT and NF-κB downstream of the TCR, but whether activation of T cell-NF-κB in vivo is required for tumor control has not been addressed. In humans and mice with progressively growing tumors, the activity of T cell-intrinsic NF-κB is often reduced. However, it is not clear if this is causal for an inability to reject transformed cells, or if it is a consequence of tumor growth. T cell-NF-κB is important for T cell survival and effector differentiation and plays an important role in enabling T cells to reject cardiac and islet allografts, suggesting the possibility that it may also be required for tumor elimination. In this study, we tested whether normal T cell-NF-κB activation is necessary for the rejection of tumors whose growth is normally controlled by the immune system.

Methods: Mice with genetically impaired T cell-NF-κB activity were subcutaneously injected with MC57-SIY tumor cells. Tumor growth was measured over time, and the anti-tumor immune response was evaluated using flow cytometry and cytokine detection assays.

Results: Mice with impaired T cell-NF-κB activity were unable to reject tumors that were otherwise eliminated by wildtype mice, despite equal accumulation of tumor-reactive T cells. In addition, specific impairment of NF-κB signaling downstream of the TCR was sufficient to prevent tumor rejection. Tumor antigen-specific T cell-IFN-γ and TNF-α production, as well as cytotoxic ability, were all reduced in mice with impaired T cell-NF-κB, suggesting an important role for this transcription factor in the effector differentiation of tumor-specific effector T cells.

Conclusions: Our results have identified the NF-κB pathway as an important signaling axis in T cells, required for the elimination of growing tumors in vivo. Maintaining or enhancing T cell-NF-κB activity may be a promising avenue for anti-tumor immunotherapy.

No MeSH data available.


Related in: MedlinePlus

T cell-IKKβ activity is required for anti-tumor effector function. CD4-cre x IKKβfl/fl and littermate control mice were subcutaneously injected with 106 MC57-SIY tumor cells and sacrificed 7 days later. a) Splenocytes were restimulated in vitro with γ-irradiated MC57-SIY tumor cells, and frequency of tumor-specific IFN-γ-secreting cells was determined by ELISpot. b) Mean spot size (from a) was used to evaluate amount of IFN-γ secretion on a per-cell basis. Results are representative of 2 experiments. c) Quantification of soluble IFN-γ and TNF-α from CD8+ splenocytes restimulated in vitro with γ-irradiated MC57-SIY tumor cells or PMA + ionomycin, as assessed by cytokine bead array. d) Mice bearing MC57-SIY tumors for 7 days were injected with a 1:1 ratio of CFSE-labeled cells loaded with (CFSElow) or without (CFSEhigh) SIY peptide. Eighteen hours later, mice were sacrificed and the presence of the target cells was assessed by flow cytometry. Results are representative of at least 2 experiments. e) Specific lysis of SIY-specific cells was calculated using the ratio of the transferred populations as described in Materials and Methods. Results combine 2 independent experiments. *p < 0.05, **p < 0.01.
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Fig3: T cell-IKKβ activity is required for anti-tumor effector function. CD4-cre x IKKβfl/fl and littermate control mice were subcutaneously injected with 106 MC57-SIY tumor cells and sacrificed 7 days later. a) Splenocytes were restimulated in vitro with γ-irradiated MC57-SIY tumor cells, and frequency of tumor-specific IFN-γ-secreting cells was determined by ELISpot. b) Mean spot size (from a) was used to evaluate amount of IFN-γ secretion on a per-cell basis. Results are representative of 2 experiments. c) Quantification of soluble IFN-γ and TNF-α from CD8+ splenocytes restimulated in vitro with γ-irradiated MC57-SIY tumor cells or PMA + ionomycin, as assessed by cytokine bead array. d) Mice bearing MC57-SIY tumors for 7 days were injected with a 1:1 ratio of CFSE-labeled cells loaded with (CFSElow) or without (CFSEhigh) SIY peptide. Eighteen hours later, mice were sacrificed and the presence of the target cells was assessed by flow cytometry. Results are representative of at least 2 experiments. e) Specific lysis of SIY-specific cells was calculated using the ratio of the transferred populations as described in Materials and Methods. Results combine 2 independent experiments. *p < 0.05, **p < 0.01.

Mentions: To determine if a differentiation step downstream of T cell proliferation was affected by lack of IKKβ, IFN-γ production upon tumor antigen re-challenge in vitro was measured by ELISpot in splenocytes harvested 7 days post-tumor injection. Fewer CD4-cre x IKKβfl/fl than wildtype splenocytes secreted IFN-γ upon restimulation with irradiated MC57-SIY tumor cells (Figure 3a). Additionally, the production of IFN-γ from CD4-cre x IKKβfl/fl mice was reduced on a per-cell basis compared to littermate controls, as assessed by mean ELISpot size (Figure 3b).Figure 3


T cell-NF-κB activation is required for tumor control in vivo.

Barnes SE, Wang Y, Chen L, Molinero LL, Gajewski TF, Evaristo C, Alegre ML - J Immunother Cancer (2015)

T cell-IKKβ activity is required for anti-tumor effector function. CD4-cre x IKKβfl/fl and littermate control mice were subcutaneously injected with 106 MC57-SIY tumor cells and sacrificed 7 days later. a) Splenocytes were restimulated in vitro with γ-irradiated MC57-SIY tumor cells, and frequency of tumor-specific IFN-γ-secreting cells was determined by ELISpot. b) Mean spot size (from a) was used to evaluate amount of IFN-γ secretion on a per-cell basis. Results are representative of 2 experiments. c) Quantification of soluble IFN-γ and TNF-α from CD8+ splenocytes restimulated in vitro with γ-irradiated MC57-SIY tumor cells or PMA + ionomycin, as assessed by cytokine bead array. d) Mice bearing MC57-SIY tumors for 7 days were injected with a 1:1 ratio of CFSE-labeled cells loaded with (CFSElow) or without (CFSEhigh) SIY peptide. Eighteen hours later, mice were sacrificed and the presence of the target cells was assessed by flow cytometry. Results are representative of at least 2 experiments. e) Specific lysis of SIY-specific cells was calculated using the ratio of the transferred populations as described in Materials and Methods. Results combine 2 independent experiments. *p < 0.05, **p < 0.01.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4308877&req=5

Fig3: T cell-IKKβ activity is required for anti-tumor effector function. CD4-cre x IKKβfl/fl and littermate control mice were subcutaneously injected with 106 MC57-SIY tumor cells and sacrificed 7 days later. a) Splenocytes were restimulated in vitro with γ-irradiated MC57-SIY tumor cells, and frequency of tumor-specific IFN-γ-secreting cells was determined by ELISpot. b) Mean spot size (from a) was used to evaluate amount of IFN-γ secretion on a per-cell basis. Results are representative of 2 experiments. c) Quantification of soluble IFN-γ and TNF-α from CD8+ splenocytes restimulated in vitro with γ-irradiated MC57-SIY tumor cells or PMA + ionomycin, as assessed by cytokine bead array. d) Mice bearing MC57-SIY tumors for 7 days were injected with a 1:1 ratio of CFSE-labeled cells loaded with (CFSElow) or without (CFSEhigh) SIY peptide. Eighteen hours later, mice were sacrificed and the presence of the target cells was assessed by flow cytometry. Results are representative of at least 2 experiments. e) Specific lysis of SIY-specific cells was calculated using the ratio of the transferred populations as described in Materials and Methods. Results combine 2 independent experiments. *p < 0.05, **p < 0.01.
Mentions: To determine if a differentiation step downstream of T cell proliferation was affected by lack of IKKβ, IFN-γ production upon tumor antigen re-challenge in vitro was measured by ELISpot in splenocytes harvested 7 days post-tumor injection. Fewer CD4-cre x IKKβfl/fl than wildtype splenocytes secreted IFN-γ upon restimulation with irradiated MC57-SIY tumor cells (Figure 3a). Additionally, the production of IFN-γ from CD4-cre x IKKβfl/fl mice was reduced on a per-cell basis compared to littermate controls, as assessed by mean ELISpot size (Figure 3b).Figure 3

Bottom Line: However, it is not clear if this is causal for an inability to reject transformed cells, or if it is a consequence of tumor growth.Tumor antigen-specific T cell-IFN-γ and TNF-α production, as well as cytotoxic ability, were all reduced in mice with impaired T cell-NF-κB, suggesting an important role for this transcription factor in the effector differentiation of tumor-specific effector T cells.Maintaining or enhancing T cell-NF-κB activity may be a promising avenue for anti-tumor immunotherapy.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, The University of Chicago, 924 E. 57th St. JFK-R312, Chicago, IL 60637 USA.

ABSTRACT

Background: T cells have the capacity to eliminate tumors but the signaling pathways by which they do so are incompletely understood. T cell priming requires activation of the transcription factors AP-1, NFAT and NF-κB downstream of the TCR, but whether activation of T cell-NF-κB in vivo is required for tumor control has not been addressed. In humans and mice with progressively growing tumors, the activity of T cell-intrinsic NF-κB is often reduced. However, it is not clear if this is causal for an inability to reject transformed cells, or if it is a consequence of tumor growth. T cell-NF-κB is important for T cell survival and effector differentiation and plays an important role in enabling T cells to reject cardiac and islet allografts, suggesting the possibility that it may also be required for tumor elimination. In this study, we tested whether normal T cell-NF-κB activation is necessary for the rejection of tumors whose growth is normally controlled by the immune system.

Methods: Mice with genetically impaired T cell-NF-κB activity were subcutaneously injected with MC57-SIY tumor cells. Tumor growth was measured over time, and the anti-tumor immune response was evaluated using flow cytometry and cytokine detection assays.

Results: Mice with impaired T cell-NF-κB activity were unable to reject tumors that were otherwise eliminated by wildtype mice, despite equal accumulation of tumor-reactive T cells. In addition, specific impairment of NF-κB signaling downstream of the TCR was sufficient to prevent tumor rejection. Tumor antigen-specific T cell-IFN-γ and TNF-α production, as well as cytotoxic ability, were all reduced in mice with impaired T cell-NF-κB, suggesting an important role for this transcription factor in the effector differentiation of tumor-specific effector T cells.

Conclusions: Our results have identified the NF-κB pathway as an important signaling axis in T cells, required for the elimination of growing tumors in vivo. Maintaining or enhancing T cell-NF-κB activity may be a promising avenue for anti-tumor immunotherapy.

No MeSH data available.


Related in: MedlinePlus