bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of colorectal cancer liver metastases on intrahepatic B cells (P2093)
Authors: Thorn Mitchell , Burga Rachel , Ngyen Cang , Licata Lauren , Espat N. , Katz Steven 
Published: January 2023

Abstract
Background: We and others have found that liver metastases (LM) mediate tolerogenic effects. B cells make up a significant proportion of liver lymphocytes but their function in the normal liver and in the setting of LM is poorly defined. Therefore, we attempted to define the features of HBC in the setting of LM. Methods: We have used a murine model of CEA+ colorectal LM to study the effects of malignancy on HBC. Tumor cells were injected into the portal circulation of C57Bl/6 mice to induce LM, and HBC were analyzed after two weeks. Results: 50% of mice with LM secreted anti-CEA antibodies, suggesting that the tumor is recognized by B cells in our model. HBC comprised 45±10% of lymphocytes in normal livers, and their frequency was reduced in mice with LM (25±3%, p=0.03). A significant reduction in the frequency of IgM+IgDlo transitional B cells, precursors of mature B cells, was observed in mice with LM (23±2% and 8±4% in normal and metastatic livers respectively, p=0.02). HBC exhibited significant down-regulation of two molecules associated with T cell activation: MHCII (7.5±3.5%, down from 31±5% in normal livers, p=0.03) and CD80 (0.9±0.4%, down from 9.6±1.4% in normal livers, p=0.02). Conclusion: The ability of HBC to mount an immune response may be compromised in the setting of LM as evidenced by reduction of HBC number and diminished HBC expression of MHCII and CD80. Further research is needed to elucidate the function of hepatic B cells during liver metastasis.
Reducing agents such as ascorbic acid or N-acetylcysteine support the chemotactic and proliferation-inducing effect of S100A4 on mesenchymal stromal cells (P2165)
Authors: Grassl Stefan , Yildiz Tatjana , Jahrsdörfer Bern , Schrezenmeier Hubert , Lotfi Ramin 
Published: January 2023

Abstract
Chronic inflammatory response is found in most advanced solid tumors with subsequent necrosis associated with release of various damage-associated molecular patterns (DAMPs) including S100A4. Mesenchymal stromal cells (MSCs) seem to interfere with the anti-tumor-immune response resulting in a poor prognosis for cancer patients, given the immunosuppressive capacity of these cells. In previous experiments we already showed that S100A4 induces MSC proliferation with an optimum at 100ng/ml. We now tested higher S100A4 concentrations and observed a bimodal effect with a second optimum achieved when using more than 2000ng S100A4/ml. Furthermore, stimulation of MSCs with graded concentrations of S100A4 inhibited dose-dependently the proliferation of lymphocytes. Based on our previous observations that S100A4 activity is enhanced in the presence of uric acid, we now tested further reducing agents like ascorbic acid, dithiothreitole, and N-acetylcysteine and could demonstrate increased chemotactic activity of S100A4 on MSCs when mentioned antioxidants were present, while they had minimal - if any - effect by themselves. Considering that MSCs respond to necrosis-associated factors, we conclude that creating an oxidative environment could be one possible strategy to inactivate not only S100A4 but also further oxidation-sensitive DAMPs like HMGB1, which contribute to the immunosuppressive nature of tumor microenvironment.
Gap junction intercellular communication enhances NK cell activation and cytotoxic capacity (P2185)
Authors: Salazar-Onfray Flavio , Tittarelli Andres , Mendoza-Naranjo Ariadna , López Mercedes , Chambers Benedict , Lundqvist Andreas , Guerrero Israel 
Published: January 2023

Abstract
Gap junctions (GJ) mediate intercellular communications between adjacent cells. Previously, we showed that connexin 43 (Cx43) was accumulated between DCs mediating antigen transfer and recruited to the immunological synapse during T cell priming. Moreover, this intercellular crosstalk contributed to T cell activation, intracellular Ca2+ responses, and cytokine release. However, the role of Cx43-GJ in NK cell activation and NK cell cytotoxicity against tumor cells, have not been elucidated. Here, we evaluated GJ role in the NK-DC interaction and in NK cell cytotoxicity against tumors. Cx43 expression was quantified on NK-DCs and in NK-tumor cell co-cultures using CX43 Abs. GJIC was evaluated by Calcein transfer and GJ inhibitors. Cytotoxicity, Granzyme-B activity and Ca2+ signaling was evaluated by flow cytometry. We found that NK cells form functional GJ with DC and tumor cells. The polarization of Cx43 increases in the NK-DCs synapsis and between NK and melanoma or K562 cells. The blocking of Cx43 using an analogue peptide or antisense RNA inhibited Ca2+ influx, Granzyme-B activity and NK cytotoxicity. NK-DC communication was bidirectional, although blocking of GJIC inhibited NK cell activation but not DC function. Moreover, Cx43-blocking inhibited tumor lysis by NK cells. Thus, our data suggest that GJ play an important role in the NK cell activation and anti-tumor effector function.
Tumor infiltrating lymphocytes derived from metastatic melanoma during intralesional immunostimulatory therapy exhibit a phenotype reflecting tumor progression (P2193)
Authors: Sieling Peter , Faries Mark , Morton Donald , Lee Delphine 
Published: January 2023

Abstract
Intralesional immunostimulatory therapy is a rational approach for in transit metastatic melanoma, as lesions are accessible and provide a source of matched tumor antigen to facilitate local and systemic immune responses. Moreover, the lesions are accessible for evaluation of the local immune response at the site of disease. To examine the immunological status at the site of disease during the course of intralesional therapy, T cells were extracted from lesions, cultured to preserve their in vivo phenotype, and expanded for functional analysis. T cells isolated from the skin lesions two weeks after initiation of intralesional therapy produced elevated Th1 cytokines relative to pre-therapy lesions. In contrast, T cells isolated at nine weeks produced decreased Th1 cytokines, but elevated Th2 cytokines, soluble IL-2Ra and IL-6, mediators associated with tumor progression. Expression of skin homing receptor cutaneous lymphocyte antigen (CLA) on lesion derived T cells correlated with Th1 cytokine production. Strikingly, lesion-derived Th1 cytokines and CLA expression were inversely correlated with tumor size during the course of therapy, whereas the phenotype of T cells derived from the blood did not change dramatically over the course of the therapy. Our studies indicate that T cells isolated from the site of disease in melanoma provide insight into the clinical state of the patient and suggest that they are critical regulators in the progression of tumor in malignant melanoma.
OX40 engagement promotes potent tumoricidial CD4+ T cells (P2199)
Authors: Hirschhorn-Cymerman Daniel , Budhu Sadna , Kitano Shigehisa , Merghoub Taha , Wolchok Jedd 
Published: January 2023

Abstract
Several immune-based strategies are currently used to treat melanoma in the clinic; however, very few result in a complete response. CD4+ T cells are potent mediators of anti-tumor immunity and adoptive transfer of specific CD4+ T cells leads to tumor regression. OX40, a costimulatory molecule expressed primarily on activated CD4+ T cells, promotes and enhances anti-tumor immunity with limited success on large tumors in mice. Here we show that OX40 engagement induces a novel CD4+ T cell population characterized by the expression of the master regulator eomesodermin that leads to both terminal differentiation and central memory phenotype, with concomitant secretion of Th1 and Th2 cytokines. This subpopulation of CD4+ T cells eradicates very advanced melanomas in mice, and an analogous population of human tumor-specific CD4+ T cells can kill melanoma in an in vitro system. Interestingly, the combination therapy effectively eliminates tumor escape variants. Our results show that these uniquely programmed effector CD4+ T cells have a distinctive phenotype with increased tumoricidal capability and support the use of immune modulation in reprogramming the phenotype of CD4+ T cells
Tumor growth and anti-tumor immunity depend upon extent of metabolic energy devoted to thermoregulation in laboratory mice (P2099)
Authors: Kokolus Kathleen , Capitano Maegan , Lee Chen-Ting , Eng Jason , Hylander Bonnie , Waight Jeremy , Gordon Christopher , Abrams Scott , Repasky Elizabeth 
Published: January 2023

Abstract
Laboratory mice are housed under relatively cool conditions and even though their core temperature remains normal, mice are cold stressed and exhibit significant increases in metabolic heat production. We compared tumor growth in mice housed at a standard ambient temperature (22oC) and at a thermoneutral temperature (30oC) which reduces metabolic effort needed for maintaining core temperature. We found significantly reduced tumor incidence and growth rates in animals housed at thermoneutral vs standard temperature using four different syngeneic tumor models, including a metastasis model. Because this difference was not seen in SCID or NUDE mice or in mice depleted of CD8+ T cells, we suspected that a prominent result of metabolic cold stress is diminished adaptive immunity. Immunohistochemistry and flow cytometry confirmed the presence of more CD8+ T cells (including antigen-specific cells) within the tumor microenvironment and spleens of animals at thermoneutral vs standard temperature. Conversely, animals at standard temperature had significantly increased infiltration of immunosuppressive cell subsets including GR-1+CD11b+ myeloid derived suppressor cells and Foxp3+ cells. These data reveal a fundamental relationship between energy utilized for thermoregulation and CD8+ T cell-dependent immunity and strongly suggest that immunological data collected from tumor bearing mice housed at standard temperature could be significantly biased by chronic cold stress.
ERK mitogen-activated protein kinase regulates Th17 cell production of IL-10 and the pathogenesis of colitis (P3197)
Authors: Liu Houpu , Yao Suxia , Qin Hongwei , Elson Charles , Cong Yingzi 
Published: January 2023

Abstract
Distinct from proinflamamtory Th17 cells which produce high levels of IL-17 and IL-22, and mediate the pathogenesis of inflammatory bowel disease, regulatory Th17 cells have recently been identified, which produce low levels of IL-17 but high level of IL-10. However, the factors and signaling pathways regulating Th17 production of IL-10 are still largely unclear. In this report, we investigated the role of ERK MAPK signal pathway, which is activated by both TGF-β and IL-6, in Th17 cell differentiation and IL-10 production. We demonstrated that blockade of ERK activation by both ERK inhibitor or siRNA specific for ERK activity inhibited Th17 cell development while upregulating Treg cells under Th17 polarization conditions. Inhibition of ERK decreased IL-6 induction of RORγt but enhanced TGF-β induction of Foxp3. Importantly, blockade of ERK activation promoted Th17 cell IL-10 production. ERK inhibitor-treated Th17 cells function differently from proinflamamtory Th17 cells, in that ERK inhibitor-treated Th17 cells possessed suppressive function in vitro as they inhibited naïve T cell proliferation and IFNγ production at the levels comparable to that of Tregs, and had a decreased potency to induce colitis in vivo. Collectively, our data demonstrated that the ERK pathway regulated Th17 differentiation and IL-10 production, and thus interfering with the ERK pathway could provide a therapeutic treatment for inflammatory bowel diseases and other Th17-related autoimmune diseases.
Development and regulation of dermal γδ T cells (P3219)
Authors: Cai Yihua , Fleming Christopher , Yan Jun 
Published: January 2023

Abstract
Recently, others and we have identified a unique subset of γδ T cells in dermis that is capable of producing IL-17. Dermal γδ T cells have been demonstrated to play a critical role in the psoriasis pathogenesis. However, it is still unclear how these cells are developed and regulated. In this study, we found that dermal γδ T cells were mainly developed from the thymus. Surprisingly, there is also an extrathymic pathway for these cells development as our data showed that bone marrow cells alone could also reconstitute the dermal γδ T cells in the mice absence of thymus (Nude mice). Although most of dermal γδ T cells are skin bona-fide residents, there were a part of γδ T cells migrated from the periphery. Such trafficking process required chemokine receptor 6. In the periphery, we found that both IL-23 and IL-1β promoted dermal γδ T cells proliferation. However, IL-23-induced dermal γδ T cell proliferation was mainly dependent on IL-1β. Additionally, IL-1β synergized with IL-23 to produce large amounts of IL-17 by dermal γδ T cells. Moreover, mice with IL-1RI deficiency had significantly decreased epidermal thickness and neutrophil infiltration induced by IL-23 or Imiquimod. Taken together, we demonstrate the development, peripheral trafficking and regulation of dermal γδ T cells, which provides new insights into understanding the biology of this newly discovered cell population and implies new mechanisms involved in the pathogenesis of skin inflammation such as psoriasis.
Interleukin-21 drives intestinal inflammation by bridging the adaptive and innate immune compartments (P3181)
Authors: Poholek Catherine , Harrington Laurie 
Published: January 2023

Abstract
Th17 CD4 T cells have been cast as pathogenic in the context of many autoimmune diseases, including Inflammatory Bowel Disease (IBD); however, the mechanism for this pathogenicity has yet to be elucidated. Based on the observation that IL-21 expression is increased in biopsies from patients with ulcerative colitis compared to healthy controls, we posit that IL-21 produced by Th17 cells mediates inflammation in the intestine. Using models of both spontaneous and CD4 T cell-dependent colitis, we show that a large number of IL-21-producing CD4 T cells are present in the intestines of mice with colitis and importantly, that IL-21 production is required for full disease progression. We find that although IL-21-/- CD4 T cells are unable to initiate disease, they produce elevated levels of IL-17A and IL-17F and are not selectively converted into Foxp3+ regulatory T cells, indicating that IL-21 is both crucial to the induction of colitis and surprisingly, is not acting via effects on the activation and differentiation of T cells. In direct support of this idea, IL-21R-/- CD4 T cells are capable of inducing disease unlike their IL-21-/- counterparts. In fact, our data demonstrate that IL-21 has an impact on the innate lymphoid cell compartment, which has previously been implicated in IBD pathogenesis. Taken together, our data show an important and previously unrecognized role for IL-21 that links CD4 T cells to innate lymphoid cells in the induction of chronic intestinal inflammation.
The magnitude of acute hepatitis is more limited by regulation of cytokine signalling than apoptosis of liver-infiltrating effector CD8 T cells (P4174)
Authors: Vo Michelle , Holz Lauren , Benseler Volker , McGuffog Claire , Hilton Douglas , McCaughan Geoffrey , Bowen David , Bertolino Patrick 
Published: January 2023

Abstract
Acute hepatitis is often mediated by CD8 T cells that kill target cells or secrete hepatotoxic cytokines. However, the parameters regulating CD8 T cell-mediated acute hepatitis are not well understood. We used the well-characterized Met-Kb Tg mouse model of acute hepatitis, in which hepatitis is mediated by lymph node activated TCR Tg CD8 recognizing their cognate antigen in the liver. To investigate whether cytokine regulation or apoptosis of CD8 T cells were critical in limiting acute hepatocellular injury, adoptive transfer experiments were performed using TCR Tg T cells deficient for either suppressor of cytokine signaling (SOCS-1) or the pro-apoptotic molecule Bim. Although there was a substantial accumulation of Bim-/- Tg cells, the outcome of hepatitis remained unchanged, suggesting that effector T cell survival was not a critical parameter in limiting liver damage. In contrast, SOCS-1-/- Tg T cells induced a heightened severity of hepatitis than their wt counterparts. SOCS-1-/- Tg cells isolated from the liver displayed upregulated IL-2Rα, required for the high affinity IL-2 receptor, and was associated with higher levels of IFN-γ expression, CTL activity, and proliferation rates, consistent with enhanced effector function. These data support a critical role for cytokines in CTL function, and demonstrate that the propensity of CD8 T cells to mediate acute hepatitis is determined by the quality rather than the number of CTLs infiltrating the liver.
Neuropathy in a mouse model of CD8+ T cell-mediated CNS demyelination (P4176)
Authors: Rainone Anthony , Fournier Sylvie 
Published: January 2023

Abstract
Several lines of evidence suggest that CD8+ T cells could contribute to the pathogenesis of many autoimmune diseases of the nervous system. Our group studies a mouse model that spontaneously develops neurological symptoms associated with demyelinated lesions in the CNS (herein referred to as L31 mice). We have shown that the demyelinating disease in L31 mice is T cell-dependent with CD8+ T cells acting as effector T cells in the pathological process while CD4+ T cells play a regulatory role. Because L31 mice exhibit motor dysfunction indicated by clasping of the limbs and difficulty walking, we wanted to determine whether the PNS was also affected. A flow cytometry approach was used to determine T cell kinetic accumulation in the CNS and PNS. Data demonstrate that CD8+ T cells accumulate in the CNS of L31 mice from early on in life while they only appear in the PNS once mice display neurological symptoms. Furthermore, immunofluoresecent studies of the CNS and PNS of these mice recapitulate the flow cytometry data and demonstrate the large extent of demyelination in the PNS of symptomatic L31 mice, which is associated with CD8+ T cell accumulation. We hypothesize that epitope spreading during the course of this CD8+ mediated demyelinating disease is the cause of PNS pathology. It will be of further interest to determine the T cell receptor specificity of the CNS and PNS infiltrating lymphocytes.
Interferon-beta therapy increases concentration of soluble interferon alpha/beta receptor in multiple sclerosis patient serum. (P4156)
Authors: Fatakdawala Taher , Skawinski Michael , Ferreira Jonathan , Stauffer Tara , Lavoie Thomas 
Published: January 2023

Abstract
Interferon-beta is a frontline treatment for Multiple Sclerosis and yet the molecule’s mechanism of action in this disease is not fully understood. We have examined the serum/plasma concentrations of soluble Interferon alpha/beta receptor 2 (sIFNAR2) using a newly developed IFNAR2 ELISA in 35 normal human donors, 23 MS patients not on IFN therapy, and 29 MS patients on IFN therapy. Other biomarkers, IFN-beta, and Type I IFN activity were also assessed in most samples. In most patients receiving IFN-beta therapy, IFN beta mass as well as IFN bioactivity can be detected in the serum. Consistent with previous literature, IFN bioactivity is lower than that which would be predicted based on IFN beta mass. For patients on IFN-beta therapy, we observe that sIFNAR2 concentration is significantly (p=0.0001) higher than that in MS patients on IFN-free therapy and relative to normal donors (p=0.0007). Normal donor sIFNAR2 concentration does not significantly differ from that of MS patients on IFN-free therapy. These results expand upon previous literature which suggests that the mRNA encoding a soluble form of the IFN receptor is increased by long term IFN-beta therapy. Data from additional samples, potential mechanisms, and correlations to other biomarkers will be discussed.
Use of gingiva-derived MSC ameliorates CIA via suppressing Th1 and Th17 and enhancing Treg cell differentiation (P4158)
Authors: Zheng Song Guo , Chen Maogen , Wang Julie , Le Anh , He Xiaoshun 
Published: January 2023

Abstract
Accumulating evidence has revealed that manipulation of bone-marrow mesenchymal stem cells (BMSCs) may have the potential to treat RA. While BMSC-based therapy faces many challenges, we reveal that substitution of gingival-derived mesenchymal stem cells (GMSCs) results in significantly improved therapeutic effects on established collagen-induced arthritis (CIA). CIA was induced with the immunization of type II collagen (CII) and CFA in DBA/1J mice. GMSCs were injected i.v. into mice on day 14 after immunization. In some experiments, injection of PC61 (anti-CD25 antibody) i.p. was used to delete Tregs in arthritic mice. Infusion of GMSCs to CIA mice significantly decreased the severity of arthritis and pathology scores, and down-regulated inflammatory cytokine (IFN-γ, IL-17A) production. Infusion of GMSCs resulted in an increase in CD4+CD39+Foxp3+ cells in arthritic mice. These increases were noted early in spleen and LN and later in synovial fluid. The increased frequency of Foxp3+ Treg cells consisted of cells that were mainly Helios negative. Infusion of GMSCs partially interfered with the progress of CIA when Treg cells were depleted. Pre-treatment of GMSCs with CD39 or CD73 inhibitor significantly reversed the protective effect of GMSCs on CIA. The role of GMSCs in controlling CIA pathology mostly depends upon CD39/CD73 signals and partially upon the induction of CD4+CD39+Foxp3+ Treg cells. GMSCs provide a promising approach for the treatment of autoimmune diseases.
Quantitative and qualitative differences in CD4+ T cell responses for subjects with symptomatic and asymptomatic West Nile virus infection (P6125)
Authors: James Eddie , Gates Theresa , May Duy , LaFond Rebecca , Malhotra Uma , Kwok William 
Published: January 2023

Abstract
The West Nile virus (WNV), a mosquito-borne flavivirus, induces a wide range of clinical manifestations in humans. While the majority of infections are essentially asymptomatic, a small percentage of inflections lead to neuroinvasive disease with symptoms ranging from mild disorientation to paralysis and death. Increased risk of symptomatic infection in immunosuppressed subjects could suggest that lack of effective immune responses against WNV may lead to worse outcomes. In this study, we utilized HLA class II tetramers to characterize the epitope specificity, frequency, and phenotype of WNV-specific T cells in subjects who had previously documented WNV infection. CD4+ T cell epitopes were present within all WNV fever proteins allowing broad characterization of WNV-specific responses. Ex vivo tetramer analysis revealed that WNV-specific CD4+ T cells were present at significantly higher frequencies in subjects with symptomatic infection than in those with no symptoms. CD4+ T cells had a memory phenotype in all WNV infected subjects, exhibited varying levels of activation, and produced multiple cytokines, including interferon-γ and IL-17. T cells from symptomatic subjects had a distinct phenotype, producing higher levels of Th2 cytokines after re-activation in vitro. Therefore, quantitative and qualitative differences in CD4+ T cell responses toward WNV are associated with neuroinvasive disease.