Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 17 (8), 983-8

Follicular Regulatory T Cells Expressing Foxp3 and Bcl-6 Suppress Germinal Center Reactions

Affiliations

Follicular Regulatory T Cells Expressing Foxp3 and Bcl-6 Suppress Germinal Center Reactions

Yeonseok Chung et al. Nat Med.

Abstract

Foxp3(+) regulatory T (T(reg)) cells suppress different types of immune responses to help maintain homeostasis in the body. How T(reg) cells regulate humoral immunity, including germinal center reactions, is unclear. Here we identify a subset of T(reg) cells expressing CXCR5 and Bcl-6 that localize to the germinal centers in mice and humans. The expression of CXCR5 on T(reg) cells depends on Bcl-6. These CXCR5(+)Bcl-6(+) T(reg) cells are absent in the thymus but can be generated de novo from CXCR5(-)Foxp3(+) natural T(reg) precursors. A lack of CXCR5(+) T(reg) cells leads to greater germinal center reactions including germinal center B cells, affinity maturation of antibodies and the differentiation of plasma cells. These results unveil a Bcl-6-CXCR5 axis in T(reg) cells that drives the development of follicular regulatory T (T(FR)) cells that function to inhibit the germinal center reactions.

Figures

Figure 1
Figure 1. CXCR5+ Treg cells co-express Bcl6 and expand upon immunization
a, Foxp3+ cells (green) in the PNA+ (red) germinal center were stained in the draining LNs. White arrow heads indicate Foxp3+ cells in PNA+ area. Scale bar shown is 50 μm. b, Lymphoid cells from the indicated secondary lymphoid tissues from naïve mice were analyzed for the expression of CXCR5, BTLA and Foxp3 in CD4+ T cells by flow cytometry. c-d, Expression of Bcl6 and CXCR5 in Foxp3+ and Foxp3- CD4+ T cells were analyzed with draining lymph node cells obtained 7 days after s.c. immunization with KLH in CFA (‘Immunized’) or without immunization (Nil). Values in d are mean ± SE. *, p<0.05; **, p<0.01 in comparison with ‘Nil’ group. a-d, Data represent two or three independent experiments. e, Expression of CXCR5, Foxp3 and Bcl6 in human tonsillar CD4+ T cells were analyzed. The dot plots represent the T cell staining from three donors.
Figure 2
Figure 2. Generation of CXCR5+Foxp3+ T cells requires Bcl6
a and b, Expression of CXCR5 and BTLA in Foxp3-(a) and Foxp3+(b) CD4+ T cells were analyzed with lymphoid cells from the draining lymph nodes or spleen of wild-type littermates or Bcl6-/- mice at 7 days after s.c. immunization with KLH in CFA. Data represent two independent experiments.
Figure 3
Figure 3. Characterization of CXCR5+Foxp3+ T cells
a, Surface expression of the indicated molecules on CXCR5+ Foxp3+ T cells. Data shown are gated on CD4+ Foxp3+ cells, and represent two independent experiments. b, The relative expression levels of the indicated genes in FACS-sorted CD25hiCD4+ T cells from Bcl6-/- mice or wild-type littermates. Data were normalized with expression amounts of Actb. *, p<0.05; **, p<0.01 in comparison with wild-type Treg. c, Suppressive activity of CD25hiCD4+ T cells from Bcl6-/- mice or wild-type littermates. Data shown are mean ± SE. **, p<0.01 in comparison with ‘naïve T cell alone’ condition. Data represent two independent experiments.
Figure 4
Figure 4. Bcl6+CXCR5+ Treg cells are generated from CXCR5- natural Treg in the periphery
a, Expression of CXCR5, BTLA and Foxp3 in CD4+ T cells from spleen or thymus (CD4+CD8-). b, Analysis of Foxp3+ and Foxp3- CD4+ T cells in the draining lymph nodes of Tcrb-/- recipients given mixture of CD25-GITR-CD44loCD62Lhi naïve CD4+ T cells (CD45.1+) and CXCR5-negative Foxp3+ T cells (CD45.2+; CXCR5-gfp+ cells from Foxp3gfp mice) after immunization with KLH in CFA (left panel). The expression of CXCR5 and Bcl6 in Foxp3+ or Foxp3- CD4+ T cells (middle panels). CD45.1/CD45.2 expression in CXCR5+Bcl6+ or CXCR5-Bcl6- population among Foxp3+ Treg cells (right panels). c, Helios expression in CXCR5+ Treg cells. Data shown are gated on CD4+ Foxp3+ cells. Data shown represent two independent experiments.
Figure 5
Figure 5. Uncontrolled germinal center reactions in scurfy mice
Expression of Bcl6 and CXCR5 on CD4+ T cells (a) or GL7 and CD95 on B cells (b) from the indicated secondary lymphoid tissues of scurfy mice and littermates (4-5 weeks old). Data are shown on CD4 gate (a) or B220 gate (b).
Figure 6
Figure 6. Both Cxcr5-/- Treg and Bcl6-/- Treg were inefficient in controlling germinal center reactions
Expression of CD25 and Foxp3 among CD4+ T cells (a), GL7+CD95+ cells among B220+ B cells (b, c), and CXCR5+BTLA+ cells among CD45.1+ population (d) in the draining lymph nodes of Tcrb-/- recipients given the mixture of naïve CD4+ T cells (CD45.1+) and regulatory T cells (CD25hi; CD45.2+) from wild-type or Cxcr5-/- mice, followed by s.c. immunization with KLH in CFA. e, The draining LNs were stained with PE-labeled PNA to visualize germinal center together with FITC-labeled anti-Foxp3. Scale bars shown are 25 μm. Data shown were obtained 9 days after immunization and represent three independent experiments. Data in c and d are pooled from two independent experiments. f-g, Mixture of naïve CD4+ T cells (CD45.1+) and Treg (CD25hi; CD45.2+) from wild-type or Bcl6-/- mice were transferred into Tcrb-/- mice, followed by s.c. immunization with KLH-NP15 in CFA. Levels of immunoglobulin specific for NP4 or NP26 in sera obtained 10 days post immunization (f). Population of NP-specific B220+ cells or B220-CD138+ plasma cells in the spleens of the recipients (g). Data shown are mean ± SE (n=5). *, p<0.05 in comparison with wild-type Treg recipients. p-values in ‘f’ were analyzed by two-way ANOVA. Data represent two independent experiments.

Comment in

Similar articles

See all similar articles

Cited by 388 PubMed Central articles

See all "Cited by" articles

References

    1. Fontenot JD, Gavin MA, Rudensky AY. Foxp3 programs the development and function of CD4+CD25+ regulatory T cells. Nat Immunol. 2003;4:330–336. - PubMed
    1. Hori S, Nomura T, Sakaguchi S. Control of regulatory T cell development by the transcription factor Foxp3. Science. 2003;299:1057–1061. - PubMed
    1. Chaudhry A, et al. CD4+ regulatory T cells control TH17 responses in a Stat3-dependent manner. Science. 2009;326:986–991. - PMC - PubMed
    1. Zheng Y, et al. Regulatory T-cell suppressor program co-opts transcription factor IRF4 to control T(H)2 responses. Nature. 2009;458:351–356. - PMC - PubMed
    1. Koch MA, et al. The transcription factor T-bet controls regulatory T cell homeostasis and function during type 1 inflammation. Nat Immunol. 2009;10:595–602. - PMC - PubMed

Publication types

MeSH terms

LinkOut - more resources

Feedback