scholarly journals Can follicular helper T cells be targeted to improve vaccine efficacy?

F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 88 ◽  
Author(s):  
Michelle A. Linterman ◽  
Danika L. Hill
Keyword(s):  
T Cells ◽  
B Cells ◽  
Plasma Cells ◽  
Subsequent Infection ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Cell Clones ◽  
Rational Vaccine Design ◽  
Selection Of

The success of most vaccines relies on the generation of antibodies to provide protection against subsequent infection; this in turn depends on a robust germinal centre (GC) response that culminates in the production of long-lived antibody-secreting plasma cells. The size and quality of the GC response are directed by a specialised subset of CD4+T cells: T follicular helper (Tfh) cells. Tfh cells provide growth and differentiation signals to GC B cells and mediate positive selection of high-affinity B cell clones in the GC, thereby determining which B cells exit the GC as plasma cells and memory B cells. Because of their central role in the production of long-lasting humoral immunity, Tfh cells represent an interesting target for rational vaccine design.

scholarly journals B cell priming for extrafollicular antibody responses requires Bcl-6 expression by T cells

2011 ◽  
Vol 208 (7) ◽  
pp. 1377-1388 ◽  
Author(s):  
Sau K. Lee ◽  
Robert J. Rigby ◽  
Dimitra Zotos ◽  
Louis M. Tsai ◽  
Shimpei Kawamoto ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Plasma Cells ◽  
Antibody Responses ◽  
B Cell Differentiation ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Microbial Infections

T follicular helper cells (Tfh cells) localize to follicles where they provide growth and selection signals to mutated germinal center (GC) B cells, thus promoting their differentiation into high affinity long-lived plasma cells and memory B cells. T-dependent B cell differentiation also occurs extrafollicularly, giving rise to unmutated plasma cells that are important for early protection against microbial infections. Bcl-6 expression in T cells has been shown to be essential for the formation of Tfh cells and GC B cells, but little is known about its requirement in physiological extrafollicular antibody responses. We use several mouse models in which extrafollicular plasma cells can be unequivocally distinguished from those of GC origin, combined with antigen-specific T and B cells, to show that the absence of T cell–expressed Bcl-6 significantly reduces T-dependent extrafollicular antibody responses. Bcl-6+ T cells appear at the T–B border soon after T cell priming and before GC formation, and these cells express low amounts of PD-1. Their appearance precedes that of Bcl-6+ PD-1hi T cells, which are found within the GC. IL-21 acts early to promote both follicular and extrafollicular antibody responses. In conclusion, Bcl-6+ T cells are necessary at B cell priming to form extrafollicular antibody responses, and these pre-GC Tfh cells can be distinguished phenotypically from GC Tfh cells.

scholarly journals Differential immune cell infiltrations between healthy periodontal and chronic periodontitis tissues

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Wei Li ◽  
Zheng Zhang ◽  
Zuo-min Wang
Keyword(s):  
T Cells ◽  
B Cells ◽  
Mast Cells ◽  
Plasma Cells ◽  
Immune Cell ◽  
Memory T Cells ◽  
Host Immunity ◽  
Memory B Cells ◽  
Helper T Cells ◽  
Follicular Helper

Abstract Background Host immunity plays an important role against oral microorganisms in periodontitis. Methods This study assessed the infiltrating immune cell subtypes in 133 healthy periodontal and 210 chronic periodontitis tissues from Gene Expression Omnibus (GEO) datasets using the CIBERSORT gene signature files. Results Plasma cells, naive B cells and neutrophils were all elevated in periodontitis tissues, when compared to those in healthy controls. In contrast, memory B cells, resting dendritic, mast cells and CD4 memory cells, as well as activated mast cells, M1 and M2 macrophages, and follicular helper T cells, were mainly present in healthy periodontal tissues. Furthermore, these periodontitis tissues generally contained a higher proportion of activated CD4 memory T cells, while the other subtypes of T cells, including resting CD4 memory T cells, CD8 T cells, follicular helper T cells (TFH) and regulatory T cells (Tregs), were relatively lower in periodontitis tissues, when compared to healthy tissues. The ratio of dendritic and mast cells and macrophages was lower in periodontitis tissues, when compared to healthy tissues. In addition, there was a significant negative association of plasma cells with most of the other immune cells, such as plasma cells vs. memory B cells (γ = − 0.84), plasma cells vs. resting dendritic cells (γ = − 0.64), plasma cells vs. resting CD4 memory T cells (γ = 0.50), plasma cells versus activated dendritic cells (γ = − 0.46), plasma cells versus TFH (γ = − 0.46), plasma cells versus macrophage M2 cells (γ = − 0.43), or plasma cells versus macrophage M1 cells (γ = − 0.40), between healthy control and periodontitis tissues. Conclusion Plasma cells, naive B cells and neutrophils were all elevated in periodontitis tissues. The infiltration of different immune cell subtypes in the periodontitis site could lead the host immunity against periodontitis.

scholarly journals IL-21 acts directly on B cells to regulate Bcl-6 expression and germinal center responses

2010 ◽  
Vol 207 (2) ◽  
pp. 353-363 ◽  
Author(s):  
Michelle A. Linterman ◽  
Laura Beaton ◽  
Di Yu ◽  
Roybel R. Ramiscal ◽  
Monika Srivastava ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Plasma Cells ◽  
Cell Formation ◽  
Affinity Maturation ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Early Memory ◽  
Bone Marrow Chimeras ◽  
Follicular Response

During T cell–dependent responses, B cells can either differentiate extrafollicularly into short-lived plasma cells or enter follicles to form germinal centers (GCs). Interactions with T follicular helper (Tfh) cells are required for GC formation and for selection of somatically mutated GC B cells. Interleukin (IL)-21 has been reported to play a role in Tfh cell formation and in B cell growth, survival, and isotype switching. To date, it is unclear whether the effect of IL-21 on GC formation is predominantly a consequence of this cytokine acting directly on the Tfh cells or if IL-21 directly influences GC B cells. We show that IL-21 acts in a B cell–intrinsic fashion to control GC B cell formation. Mixed bone marrow chimeras identified a significant B cell–autonomous effect of IL-21 receptor (R) signaling throughout all stages of the GC response. IL-21 deficiency profoundly impaired affinity maturation and reduced the proportion of IgG1+ GC B cells but did not affect formation of early memory B cells. IL-21R was required on GC B cells for maximal expression of Bcl-6. In contrast to the requirement for IL-21 in the follicular response to sheep red blood cells, a purely extrafollicular antibody response to Salmonella dominated by IgG2a was intact in the absence of IL-21.

Establishment of An Angioimmunoblastic T-Cell Lymphoma (AITL) Model in the NOG Mouse

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 5207-5207
Author(s):  
Asahi Ito ◽  
Takashi Ishida ◽  
Fumihiko Sato ◽  
Fumiko Mori ◽  
Ayako Masaki ◽  
...  
Keyword(s):  
B Cells ◽  
Plasma Cells ◽  
Conflicts Of Interest ◽  
Treatment Modalities ◽  
Medium Size ◽  
Double Immunostaining ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Novel Treatment ◽  
Nog Mice

Abstract Abstract 5207 The aim of the present study was to establish a murine AITL model. We inoculated cells from affected LN of an AITL patient intraperitoneally into NOG mice. Hepatosplenomegaly developed in these animals about 2 months later, and normal splenic architecture was replaced by multi-focal deposit of lymphocytes and numerous blood vessels. Some of the former consisted of AITL cells characterized by small to medium size, and clear to pale cytoplasm. The remaining lymphocytes were non-neoplastic reactive cells including CD8-positive cells, B cells, and plasma cells. Double immunostaining revealed that the neoplastic cells were positive for both UCHL-1 (CD45RO) and BCL-6. In addition, significant levels of human IgG/A/M were detected in these animals. The AITL cells engrafted in the NOG mice indeed functioned as follicular helper T (Tfh) cells and induced antibody production by B-cells, consistent with recent evidence that AITL is a neoplasm originating from Tfh cells. These clinical and histological features in the mice are almost identical to those seen in AITL patients. Cells from spleens of affected animals could be serially transplanted, with enrichment of the AITL cells together with reduction of the reactive cells at each passage. This phenomenon might reflect the progressive nature of AITL. TCRB analysis demonstrated that the AITL clone in the mice was identical to that from the donating patient. This is the first mouse model of AITL, and could be a powerful tool for investigating, and developing novel treatment modalities for this type of lymphoma. Disclosures: No relevant conflicts of interest to declare.

scholarly journals ICAMs support B cell interactions with T follicular helper cells and promote clonal selection

2017 ◽  
Vol 214 (11) ◽  
pp. 3435-3448 ◽  
Author(s):  
Irina Zaretsky ◽  
Ofir Atrakchi ◽  
Roei D. Mazor ◽  
Liat Stoler-Barak ◽  
Adi Biram ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Antigen Presentation ◽  
Clonal Expansion ◽  
Cell Interactions ◽  
Antigen Uptake ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Cell Clones ◽  
Wide Range

The germinal center (GC) reaction begins with a diverse and expanded group of B cell clones bearing a wide range of antibody affinities. During GC colonization, B cells engage in long-lasting interactions with T follicular helper (Tfh) cells, a process that depends on antigen uptake and antigen presentation to the Tfh cells. How long-lasting T–B interactions and B cell clonal expansion are regulated by antigen presentation remains unclear. Here, we use in vivo B cell competition models and intravital imaging to examine the adhesive mechanisms governing B cell selection for GC colonization. We find that intercellular adhesion molecule 1 (ICAM-1) and ICAM-2 on B cells are essential for long-lasting cognate Tfh–B cell interactions and efficient selection of low-affinity B cell clones for proliferative clonal expansion. Thus, B cell ICAMs promote efficient antibody immune response by enhancement of T cell help to cognate B cells.

scholarly journals CXCR5+PD-1+ follicular helper CD8 T cells control B cell tolerance

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Yuhong Chen ◽  
Mei Yu ◽  
Yongwei Zheng ◽  
Guoping Fu ◽  
Gang Xin ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Cell ◽  
Cd8 T Cells ◽  
T Cell Subsets ◽  
Cell Tolerance ◽  
B Cell Tolerance ◽  
Autoantibody Production ◽  
Tfh Cells ◽  
Follicular Helper

Abstract Many autoimmune diseases are characterized by the production of autoantibodies. The current view is that CD4+ T follicular helper (Tfh) cells are the main subset regulating autoreactive B cells. Here we report a CXCR5+PD1+ Tfh subset of CD8+ T cells whose development and function are negatively modulated by Stat5. These CD8+ Tfh cells regulate the germinal center B cell response and control autoantibody production, as deficiency of Stat5 in CD8 T cells leads to an increase of CD8+ Tfh cells, resulting in the breakdown of B cell tolerance and concomitant autoantibody production. CD8+ Tfh cells share similar gene signatures with CD4+ Tfh, and require CD40L/CD40 and TCR/MHCI interactions to deliver help to B cells. Our study thus highlights the diversity of follicular T cell subsets that contribute to the breakdown of B-cell tolerance.

scholarly journals Mucosal T follicular helper cells in SIV-infected rhesus macaques: contributing role of IL-27

2019 ◽  
Vol 12 (4) ◽  
pp. 1038-1054 ◽  
Author(s):  
Félicien Moukambi ◽  
Henintsoa Rabezanahary ◽  
Yasmina Fortier ◽  
Vasco Rodrigues ◽  
Julien Clain ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
Cd4 T Cells ◽  
Rhesus Macaques ◽  
T Follicular Helper Cells ◽  
Mesenteric Lymph Nodes ◽  
Tfh Cells ◽  
Helper Cells ◽  
Follicular Helper ◽  
Memory Cd4 T Cells

AbstractMesenteric lymph nodes (MLNs), that drain the large and small intestine, are critical sites for the induction of oral tolerance. Although depletion of CD4 T cells in the intestinal lamina propria is a hallmark of HIV infection, CD4 T cell dynamics in MLNs is less known due to the lack of accessibility to these LNs. We demonstrate the early loss of memory CD4 T cells, including T follicular helper cells (Tfh) and a remodeling of MLN architecture in SIV-infected rhesus macaques (RMs). Along with the loss of Tfh cells, we observe the loss of memory B cells and of germinal center B cells. Tfh cells display a Th1 profile with increased levels of the transcription factors that negatively impact on Tfh differentiation and of Stat5 phosphorylation. MLNs of SIV-infected RMs display lower mRNA transcripts encoding for IL-12, IL-23, and IL-35, whereas those coding for IL-27 are not impaired in MLNs. In vitro, IL-27 negatively impacts on Tfh cells and recapitulates the profile observed in SIV-infected RMs. Therefore, early defects of memory CD4 T cells, as well of Tfh cells in MLNs, which play a central role in regulating the mucosal immune response, may have major implications for Aids.

scholarly journals BCL6 orchestrates Tfh cell differentiation via multiple distinct mechanisms

2015 ◽  
Vol 212 (4) ◽  
pp. 539-553 ◽  
Author(s):  
Katerina Hatzi ◽  
J. Philip Nance ◽  
Mark A. Kroenke ◽  
Marcella Bothwell ◽  
Elias K. Haddad ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
Tcr Signaling ◽  
Cell Fates ◽  
Binding Motifs ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Distinct Cell ◽  
T Cell Help ◽  
External Stimuli

Follicular helper T cells (Tfh cells) are required for T cell help to B cells, and BCL6 is the defining transcription factor of Tfh cells. However, the functions of BCL6 in Tfh cells have largely remained unclear. Here we defined the BCL6 cistrome in primary human germinal center Tfh cells to assess mechanisms of BCL6 regulation of CD4 T cells, comparing and contrasting BCL6 function in T and B cells. BCL6 primarily acts as a repressor in Tfh cells, and BCL6 binding was associated with control of Tfh cell migration and repression of alternative cell fates. Interestingly, although some BCL6-bound genes possessed BCL6 DNA–binding motifs, many BCL6-bound loci were instead characterized by the presence of DNA motifs for AP1 or STAT. AP1 complexes are key positive downstream mediators of TCR signaling and external stimuli. We show that BCL6 can directly bind AP1, and BCL6 depends on AP1 for recruitment to BCL6-binding sites with AP1 motifs, suggesting that BCL6 subverts AP1 activity. These findings reveal that BCL6 has broad and multifaceted effects on Tfh biology and provide insight into how this master regulator mediates distinct cell context–dependent phenotypes.

scholarly journals Differentiation of germinal center B cells into plasma cells is initiated by high-affinity antigen and completed by Tfh cells

2017 ◽  
Vol 214 (5) ◽  
pp. 1259-1267 ◽  
Author(s):  
Nike J. Kräutler ◽  
Dan Suan ◽  
Danyal Butt ◽  
Katherine Bourne ◽  
Jana R. Hermes ◽  
...  
Keyword(s):  
B Cells ◽  
Germinal Center ◽  
Protective Immunity ◽  
Plasma Cells ◽  
Discrete Subset ◽  
Autoantibody Production ◽  
High Affinity ◽  
Tfh Cells ◽  
Follicular Helper

Plasma cells (PCs) derived from germinal centers (GCs) secrete the high-affinity antibodies required for long-term serological immunity. Nevertheless, the process whereby GC B cells differentiate into PCs is uncharacterized, and the mechanism underlying the selective PC differentiation of only high-affinity GC B cells remains unknown. In this study, we show that differentiation into PCs is induced among a discrete subset of high-affinity B cells residing within the light zone of the GC. Initiation of differentiation required signals delivered upon engagement with intact antigen. Signals delivered by T follicular helper cells were not required to initiate differentiation but were essential to complete the differentiation process and drive migration of maturing PCs through the dark zone and out of the GC. This bipartite or two-signal mechanism has likely evolved to both sustain protective immunity and avoid autoantibody production.

scholarly journals The Tumor Microenvironment in Follicular Lymphoma: Its Pro-Malignancy Role with Therapeutic Potential

2021 ◽  
Vol 22 (10) ◽  
pp. 5352
Author(s):  
Takashi Watanabe
Keyword(s):  
T Cells ◽  
B Cells ◽  
Follicular Lymphoma ◽  
Therapeutic Potential ◽  
Cytotoxic T Cells ◽  
Interleukin 4 ◽  
Cell Frequency ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Reticular Cells

In the follicular lymphoma (FL) microenvironment, CXCR5+ICOS+PD1+BCL6+ follicular helper T (Tfh) cells, which closely correlate with FL B cells in neoplastic follicles, play a major role in supporting FL. Interleukin-4 secreted by Tfh cells triggers the upregulation of the lymphocyte chemoattractant CXCL12 in stromal cell precursors, in particular by fibroblastic reticular cells (FRCs). In turn, mesenchymal fistromal cells (MSCs) can be committed to FRC differentiation in the bone marrow and lymph nodes involved by FL. Noteworthy, MSCs can promote the differentiation of Tfh cells into highly immunosuppressive T-follicular regulatory cells. The tumor suppressor HVEM is highly mutated in FL cells, and its deficiency increases Tfh cell frequency. In contrast, PI3Kδ inhibition impedes the recruitment of Tfh/regulatory T cells and impairs the proliferation of follicular dendritic cells (FDCs) and FDC-induced angiogenesis. Since TIGIT ligands are expressed by FDCs, the immune checkpoint receptor TIGIT plays an important role in tumor-infiltrating T cells. Thus, TIGIT blockade might invigorate cytotoxic T cells in the FL microenvironment. Given their potential to simultaneously reduce the neoplastic B cells, Tfh, and TFR cells could also reinforce the effects of the cytotoxic T cells. This combinatory strategy should be explored as a treatment option to tackle FL.

Sign in / Sign up

Export Citation Format

Share Document