Constitutive CD40L Expression on B Cells Prematurely Terminates Germinal Center Response and Leads to Augmented Plasma Cell Production in T Cell Areas

Abstract Background Germinal center derived memory B cells and plasma cells constitute, in health and during EBV reactivation, the largest functional EBV reservoir. Hence, by reducing germinal center derived formation of memory B cells and plasma cells, EBV loads may be reduced. Animal and in-vitro models have shown that IL-21 can support memory B and plasma cell formation and thereby potentially contribute to EBV persistence. However, IL-21 also displays anti-viral effects, as mice models have shown that CD4+ T cell produced IL-21 is critical for the differentiation, function and survival of anti-viral CD8+ T cells able to contain chronic virus infections. Case presentation We present immunological work-up (flow-cytometry, ELISA and genetics) related to a patient suffering from a condition resembling B cell chronic active EBV infection, albeit with moderately elevated EBV copy numbers. No mutations in genes associated with EBV disease, common variable immunodeficiency or pertaining to the IL-21 signaling pathway (including hypermorphic IL-21 mutations) were found. Increased (> 5-fold increase 7 days post-vaccination) CD4+ T cell produced (p < 0.01) and extracellular IL-21 levels characterized our patient and coexisted with: CD8+ lymphopenia, B lymphopenia, hypogammaglobulinemia, compromised memory B cell differentiation, absent induction of B-cell lymphoma 6 protein (Bcl-6) dependent peripheral follicular helper T cells (pTFH, p = 0.01), reduced frequencies of peripheral CD4+ Bcl-6+ T cells (p = 0.05), compromised plasmablast differentiation (reduced protein vaccine responses (p < 0.001) as well as reduced Treg frequencies. Supporting IL-21 mediated suppression of pTFH formation, pTFH and CD4+ IL-21+ frequencies were strongly inversely correlated, prior to and after vaccination, in the patient and in controls, Spearman’s rho: − 0.86, p < 0.001. Conclusions To the best of our knowledge, this is the first report of elevated CD4+ IL-21+ T cell frequencies in human EBV disease. IL-21 overproduction may, apart from driving T cell mediated anti-EBV responses, disrupt germinal center derived memory B cell and plasma cell formation, and thereby contribute to EBV disease control.

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Paracrine Regulation of Germinal Center B Cell Adhesion through the c-Met–Hepatocyte Growth Factor/Scatter Factor Pathway

Journal of Experimental Medicine ◽

10.1084/jem.185.12.2121 ◽

1997 ◽

Vol 185 (12) ◽

pp. 2121-2131 ◽

Cited By ~ 84

Author(s):

Robbert van der Voort ◽

Taher E.I. Taher ◽

Robert M.J. Keehnen ◽

Lia Smit ◽

Martijn Groenink ◽

...

Keyword(s):

Cell Adhesion ◽

T Cell ◽

B Cells ◽

Growth Factor ◽

Hepatocyte Growth Factor ◽

Tyrosine Kinase ◽

B Cell ◽

Germinal Center ◽

Scatter Factor ◽

Hepatocyte Growth

T cell–dependent humoral immune responses are initiated by the activation of naive B cells in the T cell areas of the secondary lymphoid tissues. This primary B cell activation leads to migration of germinal center (GC) cell precursors into B cell follicles where they engage follicular dendritic cells (FDC) and T cells, and differentiate into memory B cells or plasma cells. Both B cell migration and interaction with FDC critically depend on integrin-mediated adhesion. To date, the physiological regulators of this adhesion were unkown. In the present report, we have identified the c-met–encoded receptor tyrosine kinase and its ligand, the growth and motility factor hepatocyte growth factor/scatter factor (HGF/SF), as a novel paracrine signaling pathway regulating B cell adhesion. We observed that c-Met is predominantly expressed on CD38+CD77+ tonsillar B cells localized in the dark zone of the GC (centroblasts). On tonsil B cells, ligation of CD40 by CD40-ligand, induces a transient strong upregulation of expression of the c-Met tyrosine kinase. Stimulation of c-Met with HGF/SF leads to receptor phosphorylation and, in addition, to enhanced integrin-mediated adhesion of B cells to both VCAM-1 and fibronectin. Importantly, the c-Met ligand HGF/SF is produced at high levels by tonsillar stromal cells thus providing signals for the regulation of adhesion and migration within the lymphoid microenvironment.

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Down-regulation of BLIMP1α by the EBV oncogene, LMP-1, disrupts the plasma cell differentiation program and prevents viral replication in B cells: implications for the pathogenesis of EBV-associated B-cell lymphomas

Blood ◽

10.1182/blood-2010-09-307710 ◽

2011 ◽

Vol 117 (22) ◽

pp. 5907-5917 ◽

Cited By ~ 64

Author(s):

Katerina Vrzalikova ◽

Martina Vockerodt ◽

Sarah Leonard ◽

Andrew Bell ◽

Wenbin Wei ◽

...

Keyword(s):

Cell Differentiation ◽

B Cells ◽

B Cell ◽

Virus Replication ◽

Plasma Cell ◽

Germinal Center ◽

Lytic Cycle ◽

Transformed Cells ◽

Down Regulation ◽

Plasma Cell Differentiation

AbstractAn important pathogenic event in Epstein-Barr virus (EBV)-associated lymphomas is the suppression of virus replication, which would otherwise lead to cell death. Because virus replication in B cells is intimately linked to their differentiation toward plasma cells, we asked whether the physiologic signals that drive normal B-cell differentiation are absent in EBV-transformed cells. We focused on BLIMP1α, a transcription factor that is required for plasma cell differentiation and that is inactivated in diffuse large B-cell lymphomas. We show that BLIMP1α expression is down-regulated after EBV infection of primary germinal center B cells and that the EBV oncogene, latent membrane protein-1 (LMP-1), is alone capable of inducing this down-regulation in these cells. Furthermore, the down-regulation of BLIMP1α by LMP-1 was accompanied by a partial disruption of the BLIMP1α transcriptional program, including the aberrant induction of MYC, the repression of which is required for terminal differentiation. Finally, we show that the ectopic expression of BLIMP1α in EBV-transformed cells can induce the viral lytic cycle. Our results suggest that LMP-1 expression in progenitor germinal center B cells could contribute to the pathogenesis of EBV-associated lymphomas by down-regulating BLIMP1α, in turn preventing plasma cell differentiation and induction of the viral lytic cycle.

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Somatic diversification in the absence of antigen-driven responses is the hallmark of the IgM+IgD+CD27+ B cell repertoire in infants

Journal of Experimental Medicine ◽

10.1084/jem.20071555 ◽

2008 ◽

Vol 205 (6) ◽

pp. 1331-1342 ◽

Cited By ~ 108

Author(s):

Sandra Weller ◽

Maria Mamani-Matsuda ◽

Capucine Picard ◽

Corinne Cordier ◽

Damiana Lecoeuche ◽

...

Keyword(s):

T Cell ◽

B Cells ◽

Immune Responses ◽

Germinal Center ◽

Early Stage ◽

Cell Repertoire ◽

Very Young Children ◽

B Cell Repertoire ◽

Somatic Diversification ◽

The Many

T cell–dependent immune responses develop soon after birth, whereas it takes 2 yr for humans to develop T cell–independent responses. We used this dissociation to analyze the repertoire diversification of IgM+IgD+CD27+ B cells (also known as “IgM memory” B cells), comparing these cells with switched B cells in children <2 yr of age, with the aim of determining whether these two subsets are developmentally related. We show that the repertoire of IgM+IgD+CD27+ B cells in the spleen and blood displays no sign of antigen-driven activation and expansion on H-CDR3 spectratyping, despite the many antigenic challenges provided by childhood vaccinations. This repertoire differed markedly from those of switched B cells and splenic germinal center B cells, even at the early stage of differentiation associated with μ heavy chain expression. These data provide evidence for the developmental diversification of IgM+IgD+CD27+ B cells, at least in very young children, outside of T cell–dependent and –independent immune responses.

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Germinal center B cell development has distinctly regulated stages completed by disengagement from T cell help

eLife ◽

10.7554/elife.19552 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 20

Author(s):

Ting-ting Zhang ◽

David G Gonzalez ◽

Christine M Cote ◽

Steven M Kerfoot ◽

Shaoli Deng ◽

...

Keyword(s):

T Cell ◽

B Cells ◽

B Cell ◽

Germinal Center ◽

B Cell Differentiation ◽

B Cell Maturation ◽

Germinal Center B Cell ◽

T Cell Help ◽

Dose Dependent

To reconcile conflicting reports on the role of CD40 signaling in germinal center (GC) formation, we examined the earliest stages of murine GC B cell differentiation. Peri-follicular GC precursors first expressed intermediate levels of BCL6 while co-expressing the transcription factors RelB and IRF4, the latter known to repress Bcl6 transcription. Transition of GC precursors to the BCL6hi follicular state was associated with cell division, although the number of required cell divisions was immunogen dose dependent. Potentiating T cell help or CD40 signaling in these GC precursors actively repressed GC B cell maturation and diverted their fate towards plasmablast differentiation, whereas depletion of CD4+ T cells promoted this initial transition. Thus while CD40 signaling in B cells is necessary to generate the immediate precursors of GC B cells, transition to the BCL6hi follicular state is promoted by a regional and transient diminution of T cell help.

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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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Intrinsic Plasma Cell Differentiation Defects in B Cell Expansion with NF-κB and T Cell Anergy Patient B Cells

Frontiers in Immunology ◽

10.3389/fimmu.2017.00913 ◽

2017 ◽

Vol 8 ◽

Cited By ~ 15

Author(s):

Swadhinya Arjunaraja ◽

Brent D. Nosé ◽

Gauthaman Sukumar ◽

Nathaniel M. Lott ◽

Clifton L. Dalgard ◽

...

Keyword(s):

Cell Differentiation ◽

T Cell ◽

B Cells ◽

B Cell ◽

Plasma Cell ◽

Cell Expansion ◽

Plasma Cell Differentiation ◽

T Cell Anergy ◽

Cell Anergy

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The HVEM-BTLA Axis Restrains T Cell Help to Germinal Center B Cells and Functions as a Cell-Extrinsic Suppressor in Lymphomagenesis

Immunity ◽

10.1016/j.immuni.2019.05.022 ◽

2019 ◽

Vol 51 (2) ◽

pp. 310-323.e7 ◽

Cited By ~ 19

Author(s):

Michelle A. Mintz ◽

James H. Felce ◽

Marissa Y. Chou ◽

Viveka Mayya ◽

Ying Xu ◽

...

Keyword(s):

T Cell ◽

B Cells ◽

Germinal Center ◽

A Cell ◽

T Cell Help ◽

Germinal Center B Cells

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Human Germinal Center CD4+CD57+T Cells Act Differently On B Cells Than Do Classical T-Helper Cells

Developmental Immunology ◽

10.1155/1995/76790 ◽

1995 ◽

Vol 4 (3) ◽

pp. 189-197 ◽

Cited By ~ 18

Author(s):

Farida Bouzahzah ◽

Alain Bosseloir ◽

Ernst Heinen ◽

Léon J. Simar

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

B Cells ◽

B Cell ◽

Germinal Center ◽

Functional Study ◽

Target Cells ◽

Helper Cells ◽

Ig Synthesis

We have isolated two subtypes of helper T cells from human tonsils: CD4+CD57+cells, mostly located in the germinal center (GC), and CD4+CD57-cells, distributed through the interfollicular areas but also present in the GC. In a functional study, we have compared the capacities of these T-cell subtypes to stimulate B cells in cocultures. In order to block T-cell proliferation while maintaining their activation level, we pretreated isolated T cells with mitomycin C prior to culture in the presence of B cells and added polyclonal activators such as PHA and Con A, combined or not with IL-2. Contrary to CD4+CD57-cells, CD4+CD57+cells did not markedly enhance B-cell proliferation. Even when sIgD-B cells typical of germinal center cells were tested, the CD4 CD57 cells had no significant effect. This is in accordance with the location of these cells: They mainly occupy the light zones of the GC where few B cells divide. Even when added to preactivated, actively proliferating cells, CD4+CD57+cells failed to modulate B-cell multiplication. On the supernatants of B-cell-T-cell cocultures, we examined by the ELISA technique the effect of T cells on Ig synthesis. Contrary to CD57-T cells, whose effect was strong, CD57+T cells weakly stimulated Ig synthesis. More IgM than IgG was generally found. Because CD57 antigen is a typical marker of natural killer cells, we tested the cytolytic activity of tonsillar CD4+CD57+cells on K562 target cells. Unlike NK cells, neither CD4+CD57+nor CD4+CD57-cells exhibit any cytotoxicity. Thus, germinal center CD4+CD57+cells are not cytolytic and do not strongly stimulate either B-cell proliferation or Ig secretion. CD4+CD57-cells, however, enhance B-cell proliferation and differentiation, thus acting like the classical helper cells of the T-dependent areas.

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