Nucleoside-modified mRNA vaccines induce potent T follicular helper and germinal center B cell responses

T follicular helper (Tfh) cells are required to develop germinal center (GC) responses and drive immunoglobulin class switch, affinity maturation, and long-term B cell memory. In this study, we characterize a recently developed vaccine platform, nucleoside-modified, purified mRNA encapsulated in lipid nanoparticles (mRNA-LNPs), that induces high levels of Tfh and GC B cells. Intradermal vaccination with nucleoside-modified mRNA-LNPs encoding various viral surface antigens elicited polyfunctional, antigen-specific, CD4+ T cell responses and potent neutralizing antibody responses in mice and nonhuman primates. Importantly, the strong antigen-specific Tfh cell response and high numbers of GC B cells and plasma cells were associated with long-lived and high-affinity neutralizing antibodies and durable protection. Comparative studies demonstrated that nucleoside-modified mRNA-LNP vaccines outperformed adjuvanted protein and inactivated virus vaccines and pathogen infection. The incorporation of noninflammatory, modified nucleosides in the mRNA is required for the production of large amounts of antigen and for robust immune responses.

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Cbl and Cbl-b control the germinal center reaction by facilitating naive B cell antigen processing

Journal of Experimental Medicine ◽

10.1084/jem.20191537 ◽

2020 ◽

Vol 217 (9) ◽

Cited By ~ 1

Author(s):

Xin Li ◽

Liying Gong ◽

Alexandre P. Meli ◽

Danielle Karo-Atar ◽

Weili Sun ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

Germinal Center ◽

Antigen Processing ◽

Cell Interaction ◽

Affinity Maturation ◽

Antigen Uptake ◽

Cell Antigen ◽

Germinal Center Reaction ◽

Follicular Helper

Antigen uptake and presentation by naive and germinal center (GC) B cells are different, with the former expressing even low-affinity BCRs efficiently capture and present sufficient antigen to T cells, whereas the latter do so more efficiently after acquiring high-affinity BCRs. We show here that antigen uptake and processing by naive but not GC B cells depend on Cbl and Cbl-b (Cbls), which consequently control naive B and cognate T follicular helper (Tfh) cell interaction and initiation of the GC reaction. Cbls mediate CD79A and CD79B ubiquitination, which is required for BCR-mediated antigen endocytosis and postendocytic sorting to lysosomes, respectively. Blockade of CD79A or CD79B ubiquitination or Cbls ligase activity is sufficient to impede BCR-mediated antigen processing and GC development. Thus, Cbls act at the entry checkpoint of the GC reaction by promoting naive B cell antigen presentation. This regulation may facilitate recruitment of naive B cells with a low-affinity BCR into GCs to initiate the process of affinity maturation.

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Cyclin D3 drives inertial cell cycling in dark zone germinal center B cells

10.1101/2020.11.17.385716 ◽

2020 ◽

Author(s):

Juhee Pae ◽

Jonatan Ersching ◽

Tiago B. R. Castro ◽

Marta Schips ◽

Luka Mesin ◽

...

Keyword(s):

Cell Cycle ◽

B Cells ◽

B Cell ◽

Germinal Center ◽

Clonal Expansion ◽

Affinity Maturation ◽

Cyclin D3 ◽

Dark Zone ◽

Follicular Helper ◽

Cell Cycle Regulator Cyclin

AbstractDuring affinity maturation, germinal center (GC) B cells alternate between proliferation and so-matic hypermutation in the dark zone (DZ) and affinity-dependent selection in the light zone (LZ). This anatomical segregation imposes that the vigorous proliferation that allows clonal expansion of positively-selected GC B cells takes place ostensibly in the absence of the signals that triggered selection in the LZ, as if by “inertia.” We find that such inertial cycles specifically require the cell cycle regulator cyclin D3. Cyclin D3 dose-dependently controls the extent to which B cells proliferate in the DZ and is essential for effective clonal expansion of GC B cells in response to strong T follicular helper (Tfh) cell help. Introduction into the Ccnd3 gene of a Burkitt lymphoma-associated gain-of-function mutation (T283A) leads to larger GCs with increased DZ proliferation and, in older mice, to clonal B cell lymphoproliferation, suggesting that the DZ inertial cell cycle program can be coopted by B cells undergoing malignant transformation.

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Marginal zone SIGN-R1+macrophages are essential for the maturation of germinal center B cells in the spleen

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1921673117 ◽

2020 ◽

Vol 117 (22) ◽

pp. 12295-12305

Author(s):

Gabriela Pirgova ◽

Anne Chauveau ◽

Andrew J. MacLean ◽

Jason G. Cyster ◽

Tal I. Arnon

Keyword(s):

B Cells ◽

B Cell ◽

Germinal Center ◽

Marginal Zone ◽

Cell Responses ◽

Functional Specification ◽

Follicular Helper ◽

Initial Activation ◽

Macrophage Subsets ◽

Specific Contribution

The mechanisms that regulate germinal center (GC) B cell responses in the spleen are not fully understood. Here we use a combination of pharmacologic and genetic approaches to delete SIGN-R1+marginal zone (MZ) macrophages and reveal their specific contribution to the regulation of humoral immunity in the spleen. We find that while SIGN-R1+macrophages were not essential for initial activation of B cells, they were required for maturation of the response and development of GC B cells. These defects could be corrected when follicular helper T (Tfh) cells were induced before macrophage ablation or when Tfh responses were enhanced. Moreover, we show that in the absence of SIGN-R1+macrophages, DCIR2+dendritic cells (DCs), which play a key role in priming Tfh responses, were unable to cluster to the interfollicular regions of the spleen and were instead displaced to the MZ. Restoring SIGN-R1+macrophages to the spleen corrected positioning of DCIR2+DCs and rescued the GC B cell response. Our study reveals a previously unappreciated role for SIGN-R1+macrophages in regulation of the GC reaction and highlights the functional specification of macrophage subsets in the MZ compartment.

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Excessive CD11c+Tbet+B cells promote aberrant TFHdifferentiation and affinity-based germinal center selection in lupus

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1901340116 ◽

2019 ◽

Vol 116 (37) ◽

pp. 18550-18560 ◽

Cited By ~ 8

Author(s):

Wenqian Zhang ◽

Huihui Zhang ◽

Shujun Liu ◽

Fucan Xia ◽

Zijian Kang ◽

...

Keyword(s):

Cell Differentiation ◽

B Cells ◽

B Cell ◽

Germinal Center ◽

Molecular Mechanisms ◽

Affinity Maturation ◽

Antibody Affinity ◽

Autoantibody Production ◽

Cell Responses ◽

Antigen Presenting

Excessive self-reactive and inadequate affinity-matured antigen-specific antibody responses have been reported to coexist in lupus, with elusive cellular and molecular mechanisms. Here, we report that the antigen-specific germinal center (GC) response―a process critical for antibody affinity maturation―is compromised in murine lupus models. Importantly, this defect can be triggered by excessive autoimmunity-relevant CD11c+Tbet+age-associated B cells (ABCs). In B cell-intrinsic Ship-deficient (ShipΔB) lupus mice, excessive CD11c+Tbet+ABCs induce deregulated follicular T-helper (TFH) cell differentiation through their potent antigen-presenting function and consequently compromise affinity-based GC selection. Excessive CD11c+Tbet+ABCs and deregulated TFHcell are also present in other lupus models and patients. Further, over-activated Toll-like receptor signaling in Ship-deficient B cells is critical for CD11c+Tbet+ABC differentiation, and blocking CD11c+Tbet+ABC differentiation in ShipΔB mice by ablating MyD88 normalizes TFHcell differentiation and rescues antigen-specific GC responses, as well as prevents autoantibody production. Our study suggests that excessive CD11c+Tbet+ABCs not only contribute significantly to autoantibody production but also compromise antigen-specific GC B-cell responses and antibody-affinity maturation, providing a cellular link between the coexisting autoantibodies and inadequate affinity-matured antigen-specific antibodies in lupus models and a potential target for treating lupus.

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A Simple Flow-Cytometric Method Measuring B Cell Surface Immunoglobulin Avidity Enables Characterization of Affinity Maturation to Influenza A Virus

mBio ◽

10.1128/mbio.01156-15 ◽

2015 ◽

Vol 6 (4) ◽

Cited By ~ 24

Author(s):

Gregory M. Frank ◽

Davide Angeletti ◽

William L. Ince ◽

James S. Gibbs ◽

Surender Khurana ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

Influenza A Virus ◽

Germinal Center ◽

Neutralizing Antibodies ◽

Influenza A ◽

Affinity Maturation ◽

Flow Cytometric Method ◽

Flow Cytometric ◽

Simple Flow

ABSTRACT Antibody (Ab) affinity maturation enables an individual to maintain immunity to an increasing number of pathogens within the limits of a total Ig production threshold. A better understanding of this process is critical for designing vaccines that generate optimal Ab responses to pathogens. Our study describes a simple flow-cytometric method that enumerates virus-specific germinal center (GC) B cells as well as their AC50, a measure of Ab avidity, defined as the antigen concentration required to detect 50% of specific B cells. Using a model of mouse Ab responses to the influenza A virus hemagglutinin (IAV HA), we obtained data indicating that AC50 decreases with time postinfection in an affinity maturation-dependent process. As proof of principle of the utility of the method, our data clearly show that relative to intranasal IAV infection, intramuscular immunization against inactivated IAV in adjuvant results in a diminished GC HA B cell response, with increased AC50 correlating with an increased serum Ab off-rate. Enabling simultaneous interrogation of both GC HA B cell quantity and quality, this technique should facilitate study of affinity maturation and rational vaccine design. IMPORTANCE Though it was first described 50 years ago, little is known about how antibody affinity maturation contributes to immunity. This question is particularly relevant to developing more effective vaccines for influenza A virus (IAV) and other viruses that are difficult vaccine targets. Limitations in methods for characterizing antigen-specific B cells have impeded progress in characterizing the quality of immune responses to vaccine and natural immunogens. In this work, we describe a simple flow cytometry-based approach that measures both the number and affinity of IAV-binding germinal center B cells specific for the IAV HA, the major target of IAV-neutralizing antibodies. Using this method, we showed that the route and form of immunization significantly impacts the quality and quantity of B cell antibody responses. This method provides a relatively simple yet powerful tool for better understanding the contribution of affinity maturation to viral immunity.

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Germinal center responses to SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals

10.1101/2021.09.16.21263686 ◽

2021 ◽

Author(s):

Katlyn Lederer ◽

Kalpana Parvathaneni ◽

Mark M Painter ◽

Emily Bettini ◽

Divyansh Agarwal ◽

...

Keyword(s):

B Cells ◽

Lymph Nodes ◽

B Cell ◽

Germinal Center ◽

Neutralizing Antibodies ◽

Needle Aspiration ◽

Memory B Cells ◽

Cell Responses ◽

Protective Antibodies ◽

B Cell Responses

Vaccine-mediated immunity often relies on the generation of protective antibodies and memory B cells, which commonly stem from germinal center (GC) reactions. An in-depth comparison of the GC responses elicited by SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals has not yet been performed due to the challenge of directly probing human lymph nodes. In this study, through a fine-needle-aspiration-based approach, we profiled the immune responses to SARS-CoV-2 mRNA vaccines in lymph nodes of healthy individuals and kidney transplant (KTX) recipients. We found that, unlike healthy subjects, KTX recipients presented deeply blunted SARS-CoV-2-specific GC B cell responses coupled with severely hindered T follicular helper cells, SARS-CoV-2 receptor-binding-domain-specific memory B cells and neutralizing antibodies. KTX recipients also displayed reduced SARS-CoV-2-specific CD4 and CD8 T cell frequencies. Broadly, these data indicate impaired GC-derived immunity in immunocompromised individuals, and suggest a GC-origin for certain humoral and memory B cell responses following mRNA vaccination.

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SARS-CoV-2 mRNA vaccines induce a robust germinal centre reaction in humans

10.21203/rs.3.rs-310773/v1 ◽

2021 ◽

Cited By ~ 2

Author(s):

Ali Ellebedy ◽

Jackson Turner ◽

Jane O'Halloran ◽

Elizaveta Kalaidina ◽

Wooseob Kim ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

Messenger Rna ◽

Neutralizing Antibodies ◽

Germinal Centre ◽

S Protein ◽

Fine Needle Aspirates ◽

Cell Responses ◽

Cell Clones ◽

Shared Epitopes

Abstract Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) messenger RNA (mRNA)-based vaccines are ~95% effective in preventing coronavirus disease 2019. However, the dynamics of antibody secreting plasmablasts (PBs) and germinal centre (GC) B cells induced by these vaccines in SARS-CoV-2 naïve and antigen-experienced humans remains unclear. Here we examined peripheral blood and/or lymph node (LN) antigen-specific B cell responses in 32 individuals who received two doses of BNT162b2, an mRNA-based vaccine encoding the full-length SARS-CoV-2 spike (S) gene. Circulating IgG- and IgA-secreting PBs targeting the S protein peaked one week after the second immunization then declined and were undetectable three weeks later. PB responses coincided with maximal levels of serum anti-S binding and neutralizing antibodies to a historical strain as well as emerging variants, especially in individuals previously infected with SARS-CoV-2, who produced the most robust serological responses. Fine needle aspirates of draining axillary LNs identified GC B cells that bind S protein in all participants sampled after primary immunization. GC responses increased after boosting and were detectable in two distinct LNs in several participants. Remarkably, high frequencies of S-binding GC B cells and PBs were maintained in draining LNs for up to seven weeks after first immunization, with a substantial fraction of the PB pool class-switched to IgA. GC B cell-derived monoclonal antibodies predominantly targeted the RBD, with fewer clones binding to the N-terminal domain or shared epitopes within the S proteins of human betacoronaviruses OC43 and HKU1. Our studies demonstrate that SARS-CoV-2 mRNA-based vaccination of humans induces a robust and persistent GC B cell response that engages pre-existing as well as new B cell clones, which enables generation of high-affinity, broad, and durable humoral immunity.

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T cell-intrinsic Interferon Regulatory Factor-1 expression suppresses differentiation of CD4 + T cell populations that support chronic gammaherpesvirus infection.

Journal of Virology ◽

10.1128/jvi.00726-21 ◽

2021 ◽

Author(s):

C. N. Jondle ◽

K. E. Johnson ◽

W. P. Mboko ◽

V. L. Tarakanova

Keyword(s):

T Cell ◽

B Cells ◽

B Cell ◽

Germinal Center ◽

T Cell Subsets ◽

Viral Reservoir ◽

B Cell Differentiation ◽

Follicular Helper ◽

Interferon Regulatory Factor 1 ◽

Latent Viral Reservoir

Gammaherpesviruses are ubiquitous pathogens that establish life-long infection and are associated with B cell lymphomas. To establish chronic infection, these viruses usurp B cell differentiation and drive a robust germinal center response to expand the latent viral reservoir and gain access to memory B cells. Germinal center B cells, while important for the establishment of latent infection, are also thought to be the target of viral transformation. The host and viral factors that impact the gammaherpesvirus-driven germinal center response are not clearly defined. We showed that global expression of the antiviral and tumor-suppressor interferon regulatory factor 1 (IRF-1) selectively attenuates the murine gammaherpesvirus 68 (MHV68)-driven germinal center response and restricts expansion of the latent viral reservoir. In this study we found that T cell intrinsic IRF-1 expression recapitulates some aspects of antiviral state imposed by IRF-1 during chronic MHV68 infection, including attenuation of the germinal center response and viral latency in the spleen. We also discovered that global and T cell-intrinsic IRF-1 deficiency leads to unhindered rise of IL-17A-expressing and follicular helper T cell populations, two CD4 + T cell subsets that support chronic MHV68 infection. Thus, this study unveils a novel aspect of antiviral activity of IRF-1 by demonstrating IRF-1-mediated suppression of specific CD4 + T cell subsets that support chronic gammaherpesvirus infection. Importance Gammaherpesviruses infect over 95% of the adult population, last the lifetime of the host, and are associated with multiple cancers. These viruses usurp the germinal center response to establish lifelong infection in memory B cells. This manipulation of B cell differentiation by the virus is thought to contribute to lymphomagenesis, though exactly how the virus precipitates malignant transformation in vivo is unclear. IRF-1, a host transcription factor and a known tumor suppressor, restricts the MHV68-driven germinal center response in a B cell-extrinsic manner. We found that T cell intrinsic IRF-1 expression attenuates the MHV68-driven germinal center response by restricting the CD4 + T follicular helper population. Further, our study identified IRF-1 as a novel negative regulator of IL-17-driven immune responses, highlighting the multifaceted role of IRF-1 in gammaherpesvirus infection.

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

Journal of Experimental Medicine ◽

10.1084/jem.20091738 ◽

2010 ◽

Vol 207 (2) ◽

pp. 353-363 ◽

Cited By ~ 496

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.

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CD10 delineates a subset of human IL-4 producing follicular helper T cells involved in the survival of follicular lymphoma B cells

Blood ◽

10.1182/blood-2015-02-625152 ◽

2015 ◽

Vol 125 (15) ◽

pp. 2381-2385 ◽

Cited By ~ 28

Author(s):

Patricia Amé-Thomas ◽

Sylvia Hoeller ◽

Catherine Artchounin ◽

Jan Misiak ◽

Mounia Sabrina Braza ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

Follicular Lymphoma ◽

B Cell ◽

Germinal Center ◽

Helper T Cells ◽

Follicular Helper T Cells ◽

Follicular Helper ◽

Key Points ◽

Cell Niche

Key Points CD10 identifies a unique subset of fully functional germinal center TFH that are activated and amplified within the FL cell niche. FL CD10pos TFH specifically display an IL-4hiIFN-γlo cytokine profile and encompass the malignant B-cell-supportive TFH subset.

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