Limits...
Epigenetic plasticity of Cd8a locus during CD8(+) T-cell development and effector differentiation and reprogramming.

Harland KL, Day EB, Apte SH, Russ BE, Doherty PC, Turner SJ, Kelso A - Nat Commun (2014)

Bottom Line: Modulation of CD8 coreceptor levels can profoundly affect T-cell sensitivity to antigen.Here we show that the heritable downregulation of CD8 during type 2 polarization of murine CD8(+) effector T cells in vitro and in vivo is associated with CpG methylation of several regions of the Cd8a locus.This persistent capacity for epigenetic reprogramming of coreceptor levels on effector CD8(+) T cells enables the heritable tuning of antigen sensitivity in parallel with changes in type 1/type 2 cytokine balance.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Microbiology and Immunology, The University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Victoria 3010, Australia [2].

ABSTRACT
Modulation of CD8 coreceptor levels can profoundly affect T-cell sensitivity to antigen. Here we show that the heritable downregulation of CD8 during type 2 polarization of murine CD8(+) effector T cells in vitro and in vivo is associated with CpG methylation of several regions of the Cd8a locus. These epigenetic modifications are maintained long-term in vivo following adoptive transfer. Even after extended type 2 polarization, however, some CD8(low) effector cells respond to interferon-γ by re-expressing CD8 and a type 1 cytokine profile in association with partial Cd8a demethylation. Cd8a methylation signatures in naive, polarized and repolarized cells are distinct from those observed during the initiation, maintenance and silencing of CD8 expression by developing T cells in the thymus. This persistent capacity for epigenetic reprogramming of coreceptor levels on effector CD8(+) T cells enables the heritable tuning of antigen sensitivity in parallel with changes in type 1/type 2 cytokine balance.

Show MeSH

Related in: MedlinePlus

CD8low T cells generated in vivo display increased methylation of Cd8a.CD8+ T cells from OT-I mice were coinjected with OVA-expressing EG7-IL-4+ or EG7-IL-4− (control) tumour cells into RAG-2−/−γc−/− mice. EG7-IL-4+ tumour recipients also received anti-IFN-γ mAb on days 0, 4 and 6. On day 9, Vα2+CD4− CD8low and CD8high splenocytes were purified from mice that received EG7-IL-4+ and control tumour, respectively, and DNA was extracted for CpG methylation analysis. Rows represent individual clones; circles represent unmethylated (open) and methylated (filled) CpG sites. **P<0.01, ***P<0.001 by χ2-test comparing percentages of CpG sites methylated at each region in CD8low cells (n=6 mice) and CD8high cells (n=3 mice). ND, no data available.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3974221&req=5

f3: CD8low T cells generated in vivo display increased methylation of Cd8a.CD8+ T cells from OT-I mice were coinjected with OVA-expressing EG7-IL-4+ or EG7-IL-4− (control) tumour cells into RAG-2−/−γc−/− mice. EG7-IL-4+ tumour recipients also received anti-IFN-γ mAb on days 0, 4 and 6. On day 9, Vα2+CD4− CD8low and CD8high splenocytes were purified from mice that received EG7-IL-4+ and control tumour, respectively, and DNA was extracted for CpG methylation analysis. Rows represent individual clones; circles represent unmethylated (open) and methylated (filled) CpG sites. **P<0.01, ***P<0.001 by χ2-test comparing percentages of CpG sites methylated at each region in CD8low cells (n=6 mice) and CD8high cells (n=3 mice). ND, no data available.

Mentions: We have previously shown CD8 downregulation and type 2 polarization of IFN-γ-deficient ovalbumin (OVA)-specific TCR transgenic OT-I cells activated in vivo in response to a tumour expressing OVA and IL-4 (refs 18, 19). To determine whether CD8low cells generated in similar conditions in vivo also displayed altered DNA methylation at the Cd8a locus, OT-I CD8+ T cells were adoptively transferred into anti-IFN-γ Ab-treated recipient mice with an IL-4-expressing OVA+ tumour (type 2 conditions) or into untreated recipients with control OVA+ tumour (neutral conditions) (Fig. 3). At day 9, CD8 was partially downregulated on OT-I cells activated in type 2 conditions, and CpG methylation at the four most informative regions of Cd8a was significantly higher in purified CD8low cells from these mice than in CD8high cells activated in vivo in the absence of IL-4 and anti-IFN-γ Ab. The patterns of methylation observed in vivo were similar to those shown in CD8low and CD8high cells activated in vitro in type 2 and neutral conditions, respectively (compare Fig. 3 with Fig. 2 and Supplementary Fig. 3). The data suggest that IL-4-dependent downregulation of CD8 is associated with increased methylation of the Cd8a locus in vivo as well as in vitro.


Epigenetic plasticity of Cd8a locus during CD8(+) T-cell development and effector differentiation and reprogramming.

Harland KL, Day EB, Apte SH, Russ BE, Doherty PC, Turner SJ, Kelso A - Nat Commun (2014)

CD8low T cells generated in vivo display increased methylation of Cd8a.CD8+ T cells from OT-I mice were coinjected with OVA-expressing EG7-IL-4+ or EG7-IL-4− (control) tumour cells into RAG-2−/−γc−/− mice. EG7-IL-4+ tumour recipients also received anti-IFN-γ mAb on days 0, 4 and 6. On day 9, Vα2+CD4− CD8low and CD8high splenocytes were purified from mice that received EG7-IL-4+ and control tumour, respectively, and DNA was extracted for CpG methylation analysis. Rows represent individual clones; circles represent unmethylated (open) and methylated (filled) CpG sites. **P<0.01, ***P<0.001 by χ2-test comparing percentages of CpG sites methylated at each region in CD8low cells (n=6 mice) and CD8high cells (n=3 mice). ND, no data available.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3974221&req=5

f3: CD8low T cells generated in vivo display increased methylation of Cd8a.CD8+ T cells from OT-I mice were coinjected with OVA-expressing EG7-IL-4+ or EG7-IL-4− (control) tumour cells into RAG-2−/−γc−/− mice. EG7-IL-4+ tumour recipients also received anti-IFN-γ mAb on days 0, 4 and 6. On day 9, Vα2+CD4− CD8low and CD8high splenocytes were purified from mice that received EG7-IL-4+ and control tumour, respectively, and DNA was extracted for CpG methylation analysis. Rows represent individual clones; circles represent unmethylated (open) and methylated (filled) CpG sites. **P<0.01, ***P<0.001 by χ2-test comparing percentages of CpG sites methylated at each region in CD8low cells (n=6 mice) and CD8high cells (n=3 mice). ND, no data available.
Mentions: We have previously shown CD8 downregulation and type 2 polarization of IFN-γ-deficient ovalbumin (OVA)-specific TCR transgenic OT-I cells activated in vivo in response to a tumour expressing OVA and IL-4 (refs 18, 19). To determine whether CD8low cells generated in similar conditions in vivo also displayed altered DNA methylation at the Cd8a locus, OT-I CD8+ T cells were adoptively transferred into anti-IFN-γ Ab-treated recipient mice with an IL-4-expressing OVA+ tumour (type 2 conditions) or into untreated recipients with control OVA+ tumour (neutral conditions) (Fig. 3). At day 9, CD8 was partially downregulated on OT-I cells activated in type 2 conditions, and CpG methylation at the four most informative regions of Cd8a was significantly higher in purified CD8low cells from these mice than in CD8high cells activated in vivo in the absence of IL-4 and anti-IFN-γ Ab. The patterns of methylation observed in vivo were similar to those shown in CD8low and CD8high cells activated in vitro in type 2 and neutral conditions, respectively (compare Fig. 3 with Fig. 2 and Supplementary Fig. 3). The data suggest that IL-4-dependent downregulation of CD8 is associated with increased methylation of the Cd8a locus in vivo as well as in vitro.

Bottom Line: Modulation of CD8 coreceptor levels can profoundly affect T-cell sensitivity to antigen.Here we show that the heritable downregulation of CD8 during type 2 polarization of murine CD8(+) effector T cells in vitro and in vivo is associated with CpG methylation of several regions of the Cd8a locus.This persistent capacity for epigenetic reprogramming of coreceptor levels on effector CD8(+) T cells enables the heritable tuning of antigen sensitivity in parallel with changes in type 1/type 2 cytokine balance.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Microbiology and Immunology, The University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Victoria 3010, Australia [2].

ABSTRACT
Modulation of CD8 coreceptor levels can profoundly affect T-cell sensitivity to antigen. Here we show that the heritable downregulation of CD8 during type 2 polarization of murine CD8(+) effector T cells in vitro and in vivo is associated with CpG methylation of several regions of the Cd8a locus. These epigenetic modifications are maintained long-term in vivo following adoptive transfer. Even after extended type 2 polarization, however, some CD8(low) effector cells respond to interferon-γ by re-expressing CD8 and a type 1 cytokine profile in association with partial Cd8a demethylation. Cd8a methylation signatures in naive, polarized and repolarized cells are distinct from those observed during the initiation, maintenance and silencing of CD8 expression by developing T cells in the thymus. This persistent capacity for epigenetic reprogramming of coreceptor levels on effector CD8(+) T cells enables the heritable tuning of antigen sensitivity in parallel with changes in type 1/type 2 cytokine balance.

Show MeSH
Related in: MedlinePlus