B Cells Are Essential for Vaccination-Induced Resistance to Virulent Toxoplasma gondii

ABSTRACT T lymphocytes and gamma interferon (IFN-γ) are known mediators of immune resistance to Toxoplasma gondii infection, but whether B cells also play an important role is not clear. We have investigated this issue using B-cell-deficient (μMT) mice. If vaccinated with attenuated T. gondii tachyzoites, μMT mice are susceptible to a challenge intraperitoneal infection with highly virulent tachyzoites that similarly vaccinated B-cell-sufficient mice resist. Susceptibility is evidenced by increased numbers of parasites at the challenge infection site and by extensive mortality. The susceptibility of B-cell-deficient mice does not appear to be caused by deficient T-cell functions or diminished capacity of vaccinated and challenged B-cell-deficient mice to produce IFN-γ. Administration of Toxoplasma-immune serum, but not nonimmune serum, to vaccinated B-cell-deficient mice significantly prolongs their survival after challenge with virulent tachyzoites. Vaccinated mice lacking Fc receptors or the fifth component of complement resist a challenge infection, suggesting that neither Fc-receptor-dependent phagocytosis of antibody-coated tachyzoites nor antibody-dependent cellular cytotoxicity nor antibody-and-complement-dependent lysis of tachyzoites is a crucial mechanism of resistance. However, Toxoplasma-immune serum effectively inhibits the infection of host cells by tachyzoites in vitro. Together, the results support the hypothesis that B cells are required for vaccination-induced resistance to virulent tachyzoites in order to produce antibodies and that antibodies may function protectively in vivo by blocking infection of host cells by tachyzoites.

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T Cell-Independent Gamma Interferon and B Cells Cooperate To Prevent Mortality Associated with DisseminatedChlamydia muridarumGenital Tract Infection

Infection and Immunity ◽

10.1128/iai.00143-18 ◽

2018 ◽

Vol 86 (7) ◽

pp. e00143-18 ◽

Cited By ~ 6

Author(s):

Taylor B. Poston ◽

Catherine M. O'Connell ◽

Jenna Girardi ◽

Jeanne E. Sullivan ◽

Uma M. Nagarajan ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

Tract Infection ◽

B Cell ◽

Gamma Interferon ◽

Wild Type ◽

Content Type ◽

Ifn Γ ◽

Deficient Mice

ABSTRACTCD4 T cells and antibody are required for optimal acquired immunity toChlamydia muridarumgenital tract infection, and T cell-mediated gamma interferon (IFN-γ) production is necessary to clear infection in the absence of humoral immunity. However, the role of T cell-independent immune responses during primary infection remains unclear. We investigated this question by inoculating wild-type and immune-deficient mice withC. muridarumCM001, a clonal isolate capable of enhanced extragenital replication. Genital inoculation of wild-type mice resulted in transient dissemination to the lungs and spleen that then was rapidly cleared from these organs. However, CM001 genital infection proved lethal forSTAT1−/−andIFNG−/−mice, in which IFN-γ signaling was absent, and forRag1−/−mice, which lacked T and B cells and in which innate IFN-γ signaling was retained. In contrast, B cell-deficient muMT mice, which can generate a Th1 response, and T cell-deficient mice with intact B cell and innate IFN-γ signaling survived. These data collectively indicate that IFN-γ prevents lethal CM001 dissemination in the absence of T cells and suggests a B cell corequirement. Adoptive transfer of convalescent-phase immune serum but not naive IgM toRag1−/−mice infected with CM001 significantly increased the survival time, while transfer of naive B cells completely rescuedRag1−/−mice from CM001 lethality. Protection was associated with a significant reduction in the lung chlamydial burden of genitally infected mice. These data reveal an important cooperation between T cell-independent B cell responses and innate IFN-γ in chlamydial host defense and suggest that interactions between T cell-independent antibody and IFN-γ are essential for limiting extragenital dissemination.

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Primary Immune Responses and Affinity Maturation Are Controlled by IgD

Frontiers in Immunology ◽

10.3389/fimmu.2021.709240 ◽

2021 ◽

Vol 12 ◽

Author(s):

Timm Amendt ◽

Omar El Ayoubi ◽

Alexandra T. Linder ◽

Gabriele Allies ◽

Marc Young ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

Antibody Production ◽

Autoimmune Diabetes ◽

Affinity Maturation ◽

Antibody Responses ◽

Cell Functions ◽

High Affinity ◽

Deficient Mice

Mature B cells co-express IgM and IgD B cell antigen receptors (BCR) on their surface. While IgM BCR expression is already essential at early stages of development, the role of the IgD-class BCR remains unclear as most B cell functions appeared unchanged in IgD-deficient mice. Here, we show that IgD-deficient mice have an accelerated rate of B cell responsiveness as they activate antibody production within 24h after immunization, whereas wildtype (WT) animals required 3 days to activate primary antibody responses. Strikingly, soluble monovalent antigen suppresses IgG antibody production induced by multivalent antigen in WT mice. In contrast, IgD-deficient mice were not able to modulate IgG responses suggesting that IgD controls the activation rate of B cells and subsequent antibody production by sensing and distinguishing antigen-valences. Using an insulin-derived peptide we tested the role of IgD in autoimmunity. We show that primary autoreactive antibody responses are generated in WT and in IgD-deficient mice. However, insulin-specific autoantibodies were detected earlier and caused more severe symptoms of autoimmune diabetes in IgD-deficient mice as compared to WT mice. The rapid control of autoimmune diabetes in WT animals was associated with the generation of high-affinity IgM that protects insulin from autoimmune degradation. In IgD-deficient mice, however, the generation of high-affinity protective IgM is delayed resulting in prolonged autoimmune diabetes. Our data suggest that IgD is required for the transition from primary, highly autoreactive, to secondary antigen-specific antibody responses generated by affinity maturation.

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Antibody-Mediated Protection against Cryptococcus neoformans Pulmonary Infection Is Dependent on B Cells

Infection and Immunity ◽

10.1128/iai.73.2.1141-1150.2005 ◽

2005 ◽

Vol 73 (2) ◽

pp. 1141-1150 ◽

Cited By ~ 53

Author(s):

Johanna Rivera ◽

Oscar Zaragoza ◽

Arturo Casadevall

Keyword(s):

B Cells ◽

B Cell ◽

Cryptococcus Neoformans ◽

Scid Mice ◽

Monocyte Chemoattractant Protein 1 ◽

Monocyte Chemoattractant ◽

Inflammatory Protein ◽

Ifn Γ ◽

Macrophage Inflammatory Protein ◽

Deficient Mice

ABSTRACT The pathogenesis of pulmonary Cryptococcus neoformans infection and the efficacy of passive immunoglobulin G1 (IgG1) administration were investigated in B-cell-deficient and C57BL/6J mice. C57BL/6J mice lived longer than B-cell-deficient mice after both intratracheal and intravenous infections. Administration of IgG1 prior to infection prolonged the survival of C57BL/6J mice but had no effect on the survival or numbers of CFU in the lungs of B-cell-deficient mice. C. neoformans infection in B-cell-deficient mice resulted in significantly higher levels of gamma interferon (IFN-γ), monocyte chemoattractant protein-1 (MCP-1), and macrophage inflammatory protein-1α (MIP-1α) than in C57BL/6J mice. IgG1 administration reduced IFN-γ and MCP-1 levels in C57BL/6J mice but not in B-cell-deficient mice. In addition, compared to its effect in C57BL/6J mice, C. neoformans infection in FcRγIII-deficient, athymic, and SCID mice significantly increased IFN-γ and MCP-1 levels. IgG1 administration was associated with reduced IFN-γ levels in C57BL/6J mice but not in FcRγIII-deficient, athymic, and SCID mice. These observations suggest that IgG1-mediated protection in this system is a consequence of alterations in the inflammatory response that translate into less damage to the host without directly reducing the fungal burden. For hosts with impaired immunities, the ineffectiveness of passive antibody (Ab) may reflect an inability to down-regulate inflammation and avoid self-damage. The results indicate an important role for B cells in host defense against C. neoformans infection and demonstrate a surprising dependence of Ab-mediated protection on B cells in this system.

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B Cells Are Essential for Moderating the Inflammatory Response and Controlling Bacterial Multiplication in a Mouse Model of Vaccination against Chlamydophila abortus Infection

Infection and Immunity ◽

10.1128/iai.00503-09 ◽

2009 ◽

Vol 77 (11) ◽

pp. 4868-4876 ◽

Cited By ~ 7

Author(s):

Antonio J. Buendía ◽

Nieves Ortega ◽

María R. Caro ◽

Laura Del Río ◽

María C. Gallego ◽

...

Keyword(s):

Immune Response ◽

B Cells ◽

Inflammatory Response ◽

B Cell ◽

Transforming Growth Factor Beta ◽

Transforming Growth Factor ◽

Immune Serum ◽

Chlamydophila Abortus ◽

Cytokines And Chemokines ◽

Deficient Mice

ABSTRACT The use of inactivated vaccines associated with suitable adjuvants has been demonstrated to confer a good level of protection against Chlamydophila abortus. However, the basis of the immune protective response induced by these vaccines has been poorly studied. B cells act as an immune regulatory population during primary infection by C. abortus. Thus, it was considered of interest to study the role of B cells in an infection after immunization with a killed vaccine. For this, C57BL/6 and B-cell-deficient mice were immunized with a killed vaccine against C. abortus using QS-21 as the adjuvant. After challenge, the course of infection was established by analysis of morbidity, C. abortus burden in the liver, and histopathological changes. The immune response induced was studied by real-time PCR techniques. Experiments involving transfer of immune serum from vaccinated or previously infected mice were also carried out. The lack of B cells reduced the protection conferred by the QS-21 adjuvant vaccine. Vaccinated B-cell-deficient mice showed a 1,000-fold-greater bacterial burden in the liver than their wild-type counterparts. Obvious differences existed in the liver, where a severe neutrophilic reaction and extended areas of necrosis were observed with vaccinated B-cell-deficient mice. An analysis of the immune response pointed to a significant increase in inflammatory cytokines and chemokines and the deficient production of transforming growth factor beta. The transfer of antibodies restored the level of protection. This study demonstrates that B cells play a crucial role in controlling C. abortus multiplication and prevent an exacerbated inflammatory response.

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Deficient Humoral Responses Underlie Susceptibility to Toxoplasma gondii in CD4-Deficient Mice

Infection and Immunity ◽

10.1128/iai.70.1.185-191.2002 ◽

2002 ◽

Vol 70 (1) ◽

pp. 185-191 ◽

Cited By ~ 72

Author(s):

Lawrence L. Johnson ◽

Peter C. Sayles

Keyword(s):

T Cells ◽

Toxoplasma Gondii ◽

Immune Serum ◽

Wild Type ◽

Ifn Γ ◽

Resistance To Infection ◽

Humoral Responses ◽

Brain Cysts ◽

Deficient Mice

ABSTRACT Resistance to infection with Toxoplasma gondii was studied in mice lacking CD4 expression. Such mice developed more brain cysts and survived for a shorter time than did wild-type controls after peroral infection with ME49 cysts. After immunization with the ts-4 strain of T. gondii, CD4-deficient mice exhibited impaired resistance to a challenge infection with virulent RH tachyzoites. Thus, deficient CD4 expression increases the susceptibility of mice to a primary peroral T. gondii infection with cysts and impairs their ability to be successfully vaccinated. CD8+ T cells from blood or spleens of Toxoplasma-infected, CD4-deficient mice expressed markers of activation at frequencies similar to those of infected wild-type mice. Production of IFN-γ in vitro was moderately depressed, and levels of Toxoplasma-specific immunoglobulin G2a in serum were substantially lower than in wild-type mice. Administration of Toxoplasma-immune serum to ts-4-vaccinated CD4-deficient mice significantly improved their resistance to RH challenge. Also, the survival of CD4-deficient mice chronically infected with ME49 was significantly prolonged by administration of immune serum. These results demonstrate that in addition to CD8+ T cells and IFN-γ, which are known to be critical for resistance, CD4+ cells also contribute significantly to protection against chronic T. gondii infections and against challenge infections with highly virulent tachyzoites in immunized mice via their role as helper cells for production of isotype-switched antibodies.

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TP53INP1 deficiency maintains murine B lymphopoiesis in aged bone marrow through redox-controlled IL-7R/STAT5 signaling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1809980116 ◽

2018 ◽

Vol 116 (1) ◽

pp. 211-216 ◽

Cited By ~ 2

Author(s):

Bochra Zidi ◽

Christelle Vincent-Fabert ◽

Laurent Pouyet ◽

Marion Seillier ◽

Amelle Vandevelde ◽

...

Keyword(s):

Oxidative Stress ◽

Bone Marrow ◽

B Cells ◽

B Cell ◽

Immune Cell ◽

B Lymphopoiesis ◽

Hematopoietic Stem ◽

Chronic Oxidative Stress ◽

The Impact ◽

Deficient Mice

Bone marrow (BM) produces all blood and immune cells deriving from hematopoietic stem cells (HSCs). The decrease of immune cell production during aging is one of the features of immunosenescence. The impact of redox dysregulation in BM aging is still poorly understood. Here we use TP53INP1-deficient (KO) mice endowed with chronic oxidative stress to assess the influence of aging-associated redox alterations in BM homeostasis. We show that TP53INP1 deletion has no impact on aging-related accumulation of HSCs. In contrast, the aging-related contraction of the lymphoid compartment is mitigated in TP53INP1 KO mice. B cells that accumulate in old KO BM are differentiating cells that can mature into functional B cells. Importantly, this phenotype results from B cell-intrinsic events associated with defective redox control. Finally, we show that oxidative stress in aged TP53INP1-deficient mice maintains STAT5 expression and activation in early B cells, driving high Pax5 expression, which provides a molecular mechanism for maintenance of B cell development upon aging.

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Lymphocyte interleukin 2 production and responsiveness are altered in patients with primary myelodysplastic syndrome

Blood ◽

10.1182/blood.v70.2.494.bloodjournal702494 ◽

1987 ◽

Vol 70 (2) ◽

pp. 494-500

Author(s):

O Ayanlar-Batuman ◽

J Shevitz ◽

UC Traub ◽

S Murphy ◽

D Sajewski

Keyword(s):

T Cells ◽

B Cells ◽

Myelodysplastic Syndrome ◽

B Cell ◽

Interleukin 2 ◽

T Cell Proliferation ◽

Cell Functions ◽

Normal Limits ◽

Stimulatory Capacity

Immunoregulatory T and B cell functions in 15 patients with primary myelodysplastic syndrome (MDS) were studied by measuring the proliferative and the stimulatory capacity of T and B cells, respectively, in autologous (auto) and allogeneic (allo) mixed lymphocyte reaction (MLR). T cell proliferation in the auto MLR was 25% of the control (P less than .02), whereas proliferation in the allo MLR was normal. When control T cells were stimulated by MDS B cells, their proliferative response was only 57% of the control (P less than .01). The mechanism responsible for these abnormalities was studied by determining the capacity of MDS and normal T cells to produce interleukin 2 (IL 2) and to generate IL 2 receptors (IL 2R) following stimulation with control and MDS B cells. In the auto MLR of MDS patients, only 3% +/- 2% of T cells developed IL 2R positivity, whereas in control cultures 12% +/- 2% of T cells were positive, as determined by immunofluorescence, using a monoclonal antibody (MoAb) directed against the IL 2R, and FACS analysis. When MDS T cells were stimulated by control B cells, IL 2R generation and the production of IL 2 were within normal limits. In contrast, when control T cells were stimulated by MDS B cells or control B cells, the MDS B cells induced production of only 26% of IL 2 as compared with control B cells. In parallel experiments, IL 2R generation in control T cells stimulated by either MDS or control B cells was similar. We conclude that in the primary MDS, T and B cell interactions are impaired. Although MDS T cells develop normal quantities of IL 2R and produce normal amounts of IL 2 when stimulated by control B cells, they are markedly impaired when stimulated by self B cells. Similarly, MDS B cells can induce IL 2R generation in control T cells but not in MDS T cells. Myelodysplastic B cells are also defective in inducing IL 2 production by normal T cells in an allo MLR. These in vitro abnormalities strongly suggest that generation of lymphocytes with immunoregulatory functions is impaired in patients with MDS.

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Accounting for B cell behaviour and sampling bias yields a superior predictor of anti-PD-L1 response in bladder cancer

10.1101/2021.03.04.433370 ◽

2021 ◽

Author(s):

Ilya A Dyugay ◽

Daniil K Lukyanov ◽

Maria A Turchaninova ◽

Andrew R Zaretsky ◽

Oybek A Khalmurzaev ◽

...

Keyword(s):

Bladder Cancer ◽

T Cell ◽

B Cells ◽

B Cell ◽

Molecular Subtype ◽

Specific Antigen ◽

Therapy Response ◽

Prognostic Indicator ◽

Molecular Signature ◽

Cell Functions

Tumor-infiltrating B cells and intratumorally-produced immunoglobulins (IG) play important roles in the tumor microenvironment and response to immunotherapy. IgG antibodies produced by intratumoral B cells may drive antibody-dependent cellular cytotoxicity (ADCC) and enhance antigen presentation by dendritic cells. Furthermore, B cells are efficient antigen-specific antigen presenters that can essentially modulate the behaviour of helper T cells. Here we investigated the role of intratumoral IG isotype and clonality in bladder cancer. Our results show that the IgG1/IgA ratio offers a strong and independent prognostic indicator for the Basal squamous molecular subtype and for the whole ImVigor210 cohort in anti-PD-L1 immunotherapy. Our findings also indicate that effector B cell functions, rather than clonally-produced antibodies, are involved in the antitumor response. High IgG1/IgA ratio was associated with relative abundance of cytotoxic genes and prominence of the IL-21/IL-21R axis suggesting importance of T cell/B cell interaction. We integrated the B, NK, and T cell components, employing immFocus-like normalization to account for the stochastic nature of tumor tissue sampling. Using a random forest model with nested cross-validation, we developed a tumor RNA-Seq-based predictor of anti-PD-L1 therapy response in muscle-invasive urothelial carcinoma. The resulting PRIMUS (PRedIctive MolecUlar Signature) predictor achieves superior sensitivity compared to PD-L1 expression scores or existing gene signatures, allowing for reliable identification of responders even within the desert patient subcohort analyzed as a hold out set.

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Vav proteins regulate peripheral B-cell survival

Blood ◽

10.1182/blood-2004-12-4894 ◽

2005 ◽

Vol 106 (7) ◽

pp. 2391-2398 ◽

Cited By ~ 33

Author(s):

Elena Vigorito ◽

Laure Gambardella ◽

Francesco Colucci ◽

Simon McAdam ◽

Martin Turner

Keyword(s):

B Cells ◽

B Cell ◽

Marginal Zone ◽

Cell Receptor ◽

Cross Linking ◽

Marginal Zone B Cells ◽

Survival Signal ◽

B Cell Survival ◽

Follicular B Cells ◽

Deficient Mice

AbstractMice lacking all 3 Vav proteins fail to produce significant numbers of recirculating follicular or marginal zone B cells. Those B cells that do mature have shortened lifespans. The constitutive nuclear factor-kappaB (NF-κB) activity of resting naive B cells required Vav function and expression of cellular reticuloendotheliosis (c-Rel). Rel-A was reduced in Vav-deficient B cells. Furthermore, expression of the NF-κB-regulated antiapoptotic genes A1 and Bcl-2 was reduced in mature Vav-deficient B cells. Overexpression of Bcl-2 restored the number of mature follicular B cells in the spleens of Vav-deficient mice. When activated by B-cell receptor (BCR) cross-linking, Vav-deficient B cells failed to activate NF-κB. Vav proteins thus regulate an NF-κB-dependent survival signal in naive B cells and are required for NF-κB function after BCR cross-linking.

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Deficiency of the B Cell-Activating Factor Receptor Results in Limited CD169+Macrophage Function during Viral Infection

Journal of Virology ◽

10.1128/jvi.02976-14 ◽

2015 ◽

Vol 89 (9) ◽

pp. 4748-4759 ◽

Cited By ~ 13

Author(s):

Haifeng C. Xu ◽

Jun Huang ◽

Vishal Khairnar ◽

Vikas Duhan ◽

Aleksandra A. Pandyra ◽

...

Keyword(s):

B Cells ◽

Viral Infection ◽

B Cell ◽

Viral Infections ◽

Type I Interferon ◽

Type I ◽

Interferon Production ◽

Immune Priming ◽

Adaptive Immune ◽

Deficient Mice

ABSTRACTThe B cell-activating factor (BAFF) is critical for B cell development and humoral immunity in mice and humans. While the role of BAFF in B cells has been widely described, its role in innate immunity remains unknown. Using BAFF receptor (BAFFR)-deficient mice, we characterized BAFFR-related innate and adaptive immune functions following infection with vesicular stomatitis virus (VSV) and lymphocytic choriomeningitis virus (LCMV). We identified a critical role for BAFFR signaling in the generation and maintenance of the CD169+macrophage compartment. Consequently,Baffr−/−mice exhibited limited induction of innate type I interferon production after viral infection. Lack of BAFFR signaling reduced virus amplification and presentation following viral infection, resulting in highly reduced antiviral adaptive immune responses. As a consequence, BAFFR-deficient mice showed exacerbated and fatal disease after viral infection. Mechanistically, transient lack of B cells inBaffr−/−animals resulted in limited lymphotoxin expression, which is critical for maintenance of CD169+cells. In conclusion, BAFFR signaling affects both innate and adaptive immune activation during viral infections.IMPORTANCEViruses cause acute and chronic infections in humans resulting in millions of deaths every year. Innate immunity is critical for the outcome of a viral infection. Innate type I interferon production can limit viral replication, while adaptive immune priming by innate immune cells induces pathogen-specific immunity with long-term protection. Here, we show that BAFFR deficiency not only perturbed B cells, but also resulted in limited CD169+macrophages. These macrophages are critical in amplifying viral particles to trigger type I interferon production and initiate adaptive immune priming. Consequently, BAFFR deficiency resulted in reduced enforced viral replication, limited type I interferon production, and reduced adaptive immunity compared to BAFFR-competent controls. As a result, BAFFR-deficient mice were predisposed to fatal viral infections. Thus, BAFFR expression is critical for innate immune activation and antiviral immunity.

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