bluuebunny/crossref_metadata_2025_split huggingface dataset:
DISTINCT ROLES OF IL-10 IN REGULATION OF PEANUT ALLERGY (140.10)
Authors: Lotoski Larisa C , Simons F Estelle R , Liem Joel , Chooniesdass Rishma , Becker Allan B , HayGlass Kent T 
Published: January 2023

Abstract
Objective: To evaluate the role of IL-10 in regulation of peanut-driven cytokine production in peanut allergic, sensitized, and clinically tolerant human populations.
Methods: Eighteen clinically peanut allergic, 8 sensitized, and 29 peanut non-allergic individuals between 6-45y were studied. PBMC were stimulated with peanut Ag alone, and in the presence of rIL-10 or anti-IL-10R neutralising Ab in short-term primary cultures. Peanut-driven Type 1, Type 2, and regulatory cytokine response profiles were quantified by ELISA.
Results: IL-10 production in response to peanut-specific stimulation was higher in peanut allergic than non-allergic individuals. Exogenous rIL-10 abrogates peanut-driven cytokine production in peanut allergics. Blocking endogenous IL-10 function has no impact on recall Type 2 cytokine responses in non-allergics. Among peanut allergics, anti-IL-10R treatment during Ag stimulation enhanced both Th2 and Th1 recall responses.
Conclusion: IL-10 and the IL-10R play no detectable role in preventing initiation of peanut specific food allergy, but may be important in limiting the intensity of peanut specific Th2 and pro-inflammatory responses in peanut allergic individuals.
Syk, a novel therapeutic target for PTLD, drives Epstein Barr Virus B cell lymphoma growth and survival through the PI3K/Akt pathway (141.23)
Authors: Hatton Olivia L , Lambert Stacie , Vaysberg Maria , Krams Sheri M , Esquivel Carlos O , Martinez Olivia M 
Published: January 2023

Abstract
Post-transplant lymphoproliferative disorder (PTLD)-associated Epstein Barr Virus (EBV)+ B cell lymphomas are a serious, and often fatal, complication of solid organ and bone marrow transplantation. In EBV+ PTLD, latent membrane protein 2a (LMP2a), a mimic of the B cell receptor, provides a constitutive survival signal to latently infected cells. This signal is transmitted through the sequestering and activation of Lyn and Syk and subsequent activation of downstream survival pathways. We hypothesized that inhibition of Syk activity would diminish growth of EBV+ B cell lymphoma lines derived from patients with PTLD. Treatment with R406, a novel Syk inhibitor, decreased proliferation and induced apoptosis of PTLD lines. While the NFkB and p38 pathways were unaffected after PTLD lines were treated with R406, both the Akt and Erk pathways were inhibited. Akt is constitutively active in these cells, and treatment with R406 led to decreased Akt-dependent autocrine IL-10 secretion. These data indicate that Syk mediates its effects on EBV+ PTLD growth and survival through activation of the PI3K/Akt pathway. Syk inhibitors, such as R406, may serve as an effective therapeutic strategy for EBV+ PTLD.
Paracrine Generation of NO by Bystander Human CD8 T Cells Augments Allogeneic Responses by Inhibiting Cytokine Deprivation-Induced Cell Death (141.3)
Authors: Choy Jonathan C. , Pober Jordan S. 
Published: January 2023

Abstract
We previously reported that NO, generated by iNOS expressed in bystander human CD8 T cells, augments the accumulation of allogeneically activated human CD8 T cells in vitro and in vivo. Here we report that iNOS-derived NO does not affect T cell proliferation but rather inhibits cell death of activated human CD8 T cells after activation by allogeneic endothelial cells in culture. Furthermore, exogenous NO does not affect activation-induced cell death of human CD8 T cells but specifically reduces death of activated T cells due to cytokine deprivation. This effect does not involve cGMP signaling, and NO does not affect the protein expression levels of Bcl-2, Bcl-xL, Mcl-1, Bim, or PUMA, which are Bcl-2-related proteins previously implicated as regulators of cytokine deprivation-induced cell death. However, NO inhibits the activity of caspases activated as a consequence of cytokine deprivation in activated T cells. This protective effect correlated with S-nitrosylation of caspases and was phenocopied by ZVAD-FMK and LEDH-FMK, pharmacological inhibitors of caspases. Our findings suggest that NO augments the accumulation of allo-activated human T cells principally by inhibiting cytokine deprivation-induced cell death through S-nitrosylation of caspases.
Cyclosporine A modifies immune-mediating and therapeutic efficacy of allogeneic perivascular porcine endothelial cell implants (141.51)
Authors: Methe Heiko , Edelman Elazer R 
Published: January 2023

Abstract
Non-syngeneic endothelial cell embedded within 3D-matrices (MEEC) when placed in the vascular adventitia control vascular repair processes. Host immunity directed against engrafted allogeneic tissue is a predominant Th1-driven immune response and a major impediment for graft survival. We aimed to identify if cyclosporine A (CsA) would enhance immune compatibility and therapeutic efficacy of allogeneic MEEC.
Pigs (n=4/group) underwent balloon injury of both carotid arteries and received a 12 days course of CsA (group 1), perivascular implants of porcine MEEC (group 2), combination of CsA and MEEC (group 3) or were left untreated (group 4). Host immune reactivity was analyzed after 28 and 90 days in 2 pigs/group respectively.
No immune reactivity against MEEC was observed in treatment groups 1 and 4. MEEC treatment alone (group 2) induced formation of IgG1 antibodies specific for the allogeneic EC and differentiation of host splenocytes into Th2 but not Th1 cytokine-producing cells. CsA-therapy reduced the frequency of IgG1 antibodies and Th2-cytokine producing splenocytes upon MEEC treatment (group 3). Compared with groups 1 and 4 treatment with MEEC (group 2) significantly inhibited luminal occlusion 28 and 90 days after balloon injury. CsA-treatment reduced the ability of MEEC to inhibit luminal occlusion.
MEEC are powerful regulators of vascular injury. MEEC failed to induce a significant Th1-driven allo-immune response but induced differentiation of splenocytes into Th2-cytokine producing cells. This induction and their therapeutic efficacy were alleviated by a 12 day course of CsA. Adventitial MEEC implants -even of allogeneic sources and without immunosuppressive treatment- may be useful in decreasing luminal narrowing in a clinical setting.
The role of Drak2 in T-cells during an alloresponse (141.7)
Authors: Weist Brian M , Walsh Craig M 
Published: January 2023

Abstract
Drak2 is a serine threonine kinase that has previously been shown to negatively regulate activation of T cells through the T cell receptor. Additionally, T cells lacking Drak2 are hypersensitive to low levels of stimulation, but are surprisingly resistant to autoimmunity in an EAE model. Since it has been hypothesized that Drak2 deficient T-cells die after activation, I tested the ability of these T cells to respond to allogeneic stimulation, which would mimic transplantation from an allogeneic donor. Using in vitro mixed lymphocyte reactions, Drak2-/- CD8+ T-cells responded less to allogeneic stimulation compared to wildtype T-cells when analyzed by CFSE dilution. Additionally, allogeneic tumors were used to determine the role of Drak2 during an in vivo allogeneic transplant. Contrary to in vitro results, Drak2-/- mice were able to clear the allogeneic tumor in vivo. Subsequently, T cells isolated from Drak2-/- mice which had cleared an allogeneic tumor displayed proliferation defects when re-challenged in vitro. In the future adoptive transfers of Drak2-/- T-cells into mice lacking B, T, and NK cells will be done to address the specific role of Drak2 in T cell mediated allorejection.
Mast cell-mediated antigen presentation regulates CD8 T cell effector functions (33.15)
Authors: Bulfone-Paus Silvia , Stelekati Erietta , Bahri Rajia , D'Orlando Orietta , Orinska Zane 
Published: January 2023

Abstract
Mast cells (MCs) - long-living cells at sites of host-environment interphase, are important players of the innate immunity and central regulatory cells in adaptive immunity. We have previously described that MCs can detect viral infections and that TLR3-activated MCs contribute to antiviral host defence. MCs can regulate CD8 T cell- dependent autoimmune responses and CD8 T cell chemotaxis. Using three model antigens, we demonstrate that MCs induce antigen-specific CD8 T cell activation and proliferation. This requires direct cell contact and MHC class I-dependent antigen cross-presentation by MCs and induces the secretion of IL-2, IFN-γ and MIP-1α by CD8 T cells. Furthermore, MCs regulate antigen-specific CD8 T cell cytotoxicity by increasing granzyme B expression and promoting CD8 T cell degranulation. MCs also upregulate their expression of costimulatory molecules, and release the T cell proliferation inducer osteopontin upon direct contact. In vivo, adoptive transfer of antigen-pulsed MCs induces MHC class I-dependent, antigen-specific CD8 T cell proliferation. Furthermore, we characterised the bidirectional crosstalk between MCs and CD8 T cells and identified a new pathway of MC activation induced by MC interaction with CD8 T cells. Specifically, a number of genes coding for proteins involved in the IFN-mediated antiviral response are upregulated upon MC-CD8 T cell interaction.
Suppression of TLR4 signaling activated CTL response by scavenger receptor SRA/CD204 (33.18)
Authors: Wang Xiangyang , Yi Huanfa , Yu Xiaofei , Subjeck John 
Published: January 2023

Abstract
Scavenger receptor A (SRA)/CD204 is known to participate in the pathogenesis of atherosclerosis and the pattern recognition of pathogen infection. However, its role in adaptive immune responses has not been well defined. Here we report that the lack of SRA/CD204 promotes TLR4 agonist augmented antigen-specific immunity, as indicated by increased CD8+ T-cell proliferation, enhanced cytolytic activity of T-effector cells, and improved control of tumor growth. Dendritic cells (DCs) deficient in SRA/CD204 display more effective immunostimulatory activities upon TLR4 engagement than those from WT counterparts. Biochemical analysis indicates that SRA/CD204 suppresses TLR4 signaling stimulated activation of transcription factor NF-kappaB and subsequent production of pro-inflammatory cytokines. Moreover, silencing of SRA/CD204 by RNA interference improves the ability of DCs to prime antigen-specific CD8 T-cells, suggesting that antigen presenting cell (APC), especially DC, plays a major role in SRA/CD204-mediated immune modulation. Our findings reveal a previously unrecognized role for SRA/CD204, a non-TLR pattern recognition receptor, as a physiological negative regulator of TLR4 signaling-elicited immune consequences.
Dasatinib potential for anti-inflammatory efficacy while avoiding suppression of T cell activation in preclinical models (33.8)
Authors: Schieven Gary L , Zhang Rosemary , Pitt Sidney , McIntyre Kim , Gillooly Kathleen , Brock Barry , Smykla Richard , Townsend Robert , Saltercid Luisa , Lee Francis 
Published: January 2023

Abstract
Dasatinib potently inhibits Src-family kinases in addition to BCR-Abl and blocks T cell responses in vitro, suggesting potential utility in the treatment of autoimmune disease. A linear relationship was observed between serum concentration and in vitro T cell proliferation IC50 values. Modeling the human PK profile, delayed dasatinib treatment of T cells after T cell stimulation in vitro led to a time dependent decrease in potency as measured by both IC50 and Emax values. Comparison of serum adjusted IC50 values from these studies to the human PK profile suggests that dasatinib at the approved 100 mg QD dose would not be able to achieve a blockade of T cell activation on a daily basis. A similar pattern was observed in preclinical in vivo models. Dasatinib was found to be completely protective in a mouse model of cardiac allograft rejection at a dose of 25 mg BID, whereas a dose of 15 mg BID was not protective. By contrast, dasatinib at a dose of 3 mg/kg BID was highly efficacious in the mouse collagen induced arthritis model. Taken together, these results suggest that dasatinib may be able to provide anti-inflammatory effects while avoiding suppression of T cell activation at clinically relevant doses.
Direct CD8:CD4 T cell interactions improve memory recall of CD8 T cells (33.9)
Authors: Romagnoli Pablo Alberto , Premenko-Lanier Mary F , Loria Gilbert David , Altman John David 
Published: January 2023

Abstract
Protection against intracellular pathogens is conferred by CD8 T cells, which require CD4 T cell help to develop into effective memory CD8 T cells. It is believed that CD4 help is provided via licensing of APCs or IL-2 secretion to optimally stimulate CD8 T cells. We propose a new model where T:T interactions also play a role in CD8 T cell memory formation.
Here, we show that endogenous CD8 T cells, detected by tetramer enrichment, can acquire MHC class II when responding to infection. Next, we demonstrate that CD11c+ APCs are the main source of this MHC class II. Finally, we show that MHC class II bearing activated CD8 T cells can directly interact with experienced CD4 T cells impacting memory recall responses of CD8 T cells in vivo.
These observations suggest that program differentiation of memory CD8 T cells involves a novel direct interaction between CD8 and CD4 T cells. Furthermore, this model may also facilitate the understanding of immune regulation exerted on CD8 T cells depending on the profile of the interacting CD4 T cell population.
Support for this Research comes from the National Institutes of Health, Grant: 1RO1AI042373-04, PI: John D. Altman.
In vitro exposure to Atrazine does not alter activation, but prevents proliferation of primary murine B cells, T cells, or macrophages (34.10)
Authors: Wetzel Scott A , Browning Diana 
Published: January 2023

Abstract
Atrazine (ATR) is one of the most widely applied herbicides in the United States. The US Environmental Protection Agency reported in 2001 that Atrazine and its primary metabolite are the most common ground water contaminants in the US. Atrazine, an estrogen disrupting compound, has been linked to abnormalities in reproduction and as well as development of human cancer. Previous studies from other labs have also implicated the immune system as a target of ATR toxicity. In this study we examined the impact of ATR on the in vitro activation and expansion of mitogen-activated primary murine B cells and primary murine TCR transgenic T cells in an antigen-driven response. In the presence of ATR we observed only minimal changes in the expression of activation markers on macrophages, B cells and T cells. While there was not an increase in apoptosis induction in the presence of ATR, there was significant inhibition of proliferation in all three cell types. Interestingly, the effect is more pronounced on cells derived from male animals, consistent with the estrogen disrupting function of ATR. Thus, it appears that ATR may allow activation of B and T lymphocytes and macrophages while at the same time inhibiting proliferation of these cells. Studies examining potential ATR-induced changes in the effector functions of these cells are underway.
Funded By NIH COBRE 2P20RR017670 Subproject 5
CD137 promotes proliferation and survival of human B cell (34.14)
Authors: Zhang Xiaoyu , Voskens Caroline J. , Sallin Michelle , Strome Scott E 
Published: January 2023

Abstract
CD137 (4-1BB) mediated co-stimulation plays an important role in directing the fate of antigen stimulated T cells and NK cells, yet its role on B cell function is currently unknown. The goal of our study was first to evaluate which external signals regulate CD137 expression on human B cells and second to define the biological effect of CD137-mediated co-stimulation on human B cells. Flow cytometric analysis was used to evaluate cell surface expression of CD137. Cell proliferation was assessed by 3H-TdR incorporation and CFSE dilution assay. Cell apoptosis was determined by Annexin V and 7-AAD staining. Here we report that CD137 is expressed on human B cells stimulated with anti-Ig. CD137 expression is enhanced by CD40 ligation and IFN-γ, and is inhibited by IL-4 and IL-10. The expression of CD137 on activated human B cells is functionally relevant, as engagement with its ligand at the time of activation stimulates B cell proliferation. Furthermore, CD137 stimulation enhances B cell survival which is associated with expression of the anti-apoptotic proteins Bcl-xl and Mcl-1. Our study demonstrates a direct role for CD137-mediated co-stimulation in defining the fate of antigen-stimulated human B cells.
Interactions between LMP1 and CD40 signals (34.15)
Authors: Stunz Laura , Bishop Gail 
Published: January 2023

Abstract
The EBV encoded protein LMP1 signals to B lymphocytes in a manner similar in many respects to the normal cellular protein CD40. Under circumstances in which LMP1, not expressed in normal latency, is re-expressed in vivo, LMP1 and CD40 are expressed in the same cells. Thus, we have used both cell line and transgenic mouse models to investigate the interaction of LMP1 and CD40 signals. CD40 and LMP1 signals cooperate in stimulation of JNK , IkBa and p38 MAPK phosphorylation in B cell lines, as well as in primary mouse B cells and BMDCs, though TRAFs 2 and 3 are degraded in a manner similar to CD40 signaling alone. Though additivity is seen in early signaling through these two pathways, in vivo effects of LMP1 + CD40 signaling do not always show cooperation. Expression of a hybrid molecule with the extracellular domain of mouse CD40 and the intracellular signaling domain of LMP1 in B cells, macrophages and dendritic cells on a CD40 negative background leads to lymphadenopathy, splenomegaly, spontaneous germinal centers, and autoantibody formation. However, when CD40 is also expressed some of these in vivo effects are ameliorated (splenomegaly, some cytokines), or delayed (autoantibody production). One interesting effect of mCD40-LMP1 signaling in vivo is elevated serum IL17, which we hypothesized is secondary to elevated IL6 production in the mCD40-LMP1tg mice. However, mice expressing both mCD40-LMP1 and mCD40 transgenes also have elevated IL6, but serum IL17 levels are not elevated, suggesting that other factors or pathways are involved.
Regulation of HSH2 Adaptor Protein Expression in B cells is Mediated by Posttranscriptional Mechanisms (34.18)
Authors: Lewis Karon C , King Rodney , Justement Louis 
Published: January 2023

Abstract
Previous studies have shown that the adaptor protein hematopoietic src homology 2 (HSH2) is expressed at low levels in resting B cells. HSH2 expression is up-regulated in response to various stimuli that promote splenic B cell survival and differentiation including α-CD40 mAb, LPS, CpG, and Blys. HSH2 expression was found to be dependent upon NF-¿B stimulation in that inhibitors of NF-¿B blocked up-regulation of HSH2 expression. HSH2 expression did not increase upon stimulation of B cells via the BCR unless cells were previously stimulated through CD40. Preliminary data reveal that HSH2 protein expression is decoupled from transcript abundance. Real-time PCR analyses show that upon α-CD40 stimulation of splenic B cells, HSH2 transcript levels remain relatively constant, whereas protein expression increases. This suggests that there are one or more posttranscriptional mechanisms in place that control HSH2 expression at the protein level. One possibility is that the untranslated regions of HSH2 mRNA contain regulatory regions responsible for translational control, which is currently under investigation. A second finding is that HSH2 turns over rapidly at the protein level in response to conditions in which the 26S proteosome is blocked with pharmacological antagonists. Thus, it is apparent that HSH2 is subject to proteolytic degradation and that this is under tight regulation. In summary, HSH2 expression is controlled by posttranscriptional mechanisms that maintain low basal expression in resting B cells, but promote increased expression in cells exposed to agonists that promote survival and differentiation.
Superoxide production influences cell cycle entry downstream of BCR ligation (34.20)
Authors: Richards Sabrina , Clark Edward A. 
Published: January 2023

Abstract
Purpose: To investigate the contribution of BCR-induced superoxides to BCR-dependent signaling outcomes. Methods: gp91phoxiKO mice were utilized. Purified B cells from WT or gp91phoxiKO mice were loaded with CFSE, and stimulated via the B cell receptor (BCR). Proliferation was determined by CFSE dilution and G1 entry by Pyronin-Y staining. Western blotting of BCR-stimulated B cells was performed to measure cell cycle proteins. WT and gp91phoxiKO mice were immunized with TI-2 and TD antigens and serum Ab titers measured using ELISA. Results: More gp91phoxiKO B cells entered G1 and knockout B cells proliferated more after BCR stimulation. Reduction in levels of p27Kip1 occurred more quickly in BCR-stimulated gp91phoxiKO B cells. gp91phoxiKO mice displayed enhanced Ag-specific Ab production after TI-2 immunization. Conclusions: Superoxide derivatives negatively regulate signaling pathways leading to BCR-dependent proliferation. The perturbation in signaling in ROS-deficient B cells lies downstream of calcium signaling but upstream of p27Kip1.
These studies supported by a Cancer Research Institute Training Grant and NIH grants GM37905 and AI44257.
Preformed CD40 ligand is expressed in effector but not regulatory CD4+ T cells, and is sufficient to induce antigen-specific B cell activation (34.4)
Authors: Koguchi Yoshinobu , Thauland Timothy J. , Gardell Jennifer L. , Buenafe Abigail C. , Slifka Mark K. , Parker David C. 
Published: January 2023

Abstract
Previously, we showed that preformed CD40 ligand (pCD40L) exists in effector CD4+ T cells and can be sent to the cell surface within minutes following antigen recognition. We tested which subsets of Th cells possess pCD40L. In vitro primed and polarized Th1 and Th17 but not Th2 and induced regulatory T (iTreg) cells possess pCD40L. Consistently, Th1 and follicular helper T cells from LCMV infected mice and Th1 and Th17 cells from mice with EAE have pCD40L. However, Th2 cells induced in vivo by papain plus OVA immunization do possess pCD40L. In contrast, natural Treg cells as well as iTreg cells from an in vivo oral tolerance model do not have pCD40L. To examine the function of pCD40L, we cultured cyclosporine A-treated Th1 cells, which maintain pCD40L expression but not de novo production of cytokines and CD40L, with a mixture of peptide-pulsed and -unpulsed B cells from WT and CD40-deficient mice. This assay revealed an antigen-specific, CD40-dependent, activation of B cells by pCD40L. Interestingly, anti-CD40L mAb can only partially neutralize this CD40-dependent activation, suggesting that the adhesion ring of the immune synapse may block access of the antibody to delivery of pCD40L to antigen-presenting B cells. pCD40L may be used by effector Th cells to deliver an activation signal to antigen-presenting APCs through the immune synapse during brief interactions that are not long enough for de-novo CD40L to be synthesized.