bluuebunny/crossref_metadata_2025_split huggingface dataset:
Liver DC modulate Foxp3 expression in allogeneic CD4+ T cells via IL-27 (145.3)
Authors: Matta Benjamin , Sumpter Tina , Raimondi Giorgio , Thomson Angus 
Published: January 2023

Abstract
Liver dendritic cells (DC) possess immunoregulatory properties that influence the nature of T cell responses. We investigated the impact of IL-27 on CD4+ T cell responses by liver DC. Both plasmacytoid DC (mPDCA-1+) and myeloid DC (CD11c+ mPDCA-1-) were immunobead-purified from livers and spleens of Flt3L-treated C57BL/6 mice. DC phenotype was analyzed by flow cytometry and cytokine levels were quantified by ELISA. Ebi-3 (a component of the IL-27 molecule) protein expression was determined by Western blot. T cell allostimulatory capacity in MLR was quantified by CFSE dilution analysis, and Foxp3+ T cells quantified by intracellular flow cytometric analysis. Liver DC exhibited reduced expression of antigen (Ag)-presenting and costimulatory molecules and induced inferior T cell proliferation compared to splenic DC. They also produced elevated levels of IL-27p28, IL-10, and IL-6, but reduced IL-12p40 levels compared to splenic DC. Liver DC expressed higher levels of Ebi-3 protein compared to spleen DC. Blockade of IL-27 in allogeneic MLR resulted in greater levels of Foxp3+ T cells when liver but not spleen DC were used as stimulators. Thus, liver DC exhibit lower Ag-presenting and costimulatory molecule expression but produce greater levels of immunoregulatory cytokines than splenic DC, which may contribute to their poor CD4+ T cell allostimulatory capacity. Interestingly, IL-27 produced by liver DC may inhibit their ability to induce Foxp3+ regulatory T cells.
Small Modular ImmunoPharmaceutical (SMIPTM) Molecules Directed at the TCR Complex Block Acute Graft Versus Host Disease and Cause Minimal Cytokine Release In Vivo (145.30)
Authors: Beckett Travis , Wang Camilla , Kim Kei , Odegard Valerie , Mohler Ken , McMahan Catherine 
Published: January 2023

Abstract
The T cell receptor complex (TCR) is a powerful therapeutic target for modulating autoimmunity and transplantation biology. A number of studies have shown that TCR/CD3-directed molecules are beneficial in mouse models of disease (e.g, acute graft vs host disease, aGVHD). However, both 145-2C11 (anti-CD3ϵ) and H57-597 (anti-TCRβ) are T cell mitogens and stimulate the activation of T cells and cytokine release in vitro and in vivo . In contrast to conventional antibodies, SMIP molecules are single chain binding proteins based on a scFv-CH2-CH3 format. Compared to their corresponding parent antibodies, SMIP molecules utilizing the 2C11 and H57 binding domains demonstrate a more robust down modulation of the TCR complex, enhanced efficacy in in vitro assays of T cell function, and significantly reduced levels of pro-inflammatory cytokines. Administration of these compounds in vivo results in significantly lower levels of cytokine release with no measurable changes in animal weight loss or adverse clinical symptoms despite dosage of 60 fold molar excess compared to the original full-length antibody. In addition, our SMIPs significantly abrogate donor cell engraftment in spleens of host animals in a parent into F1 model of aGVHD. These observations indicate that features in the SMIP format could generate novel anti-human CD3-directed therapeutics with greatly reduced levels of cytokine release in vivo.
Dendritic cells and Regulatory T cells facilitate donor engraftment after hematopoietic stem cell transplantation (145.35)
Authors: Langfitt Deanna , Wallace Nikki , Gaines Sara , Dallas Mari 
Published: January 2023

Abstract
The role of thymic DCs in facilitating donor engraftment after hematopoietic stem cell transplantation (HSCT) has not been investigated. Here we show addition of ex-vivo generated DCs accelerates thymic engraftment as well as enhances T cell recovery after HSCT. We also show the ability of regulatory T cells (Tregs) to facilitate engraftment. Control group received 103 lin-sca-1+c-kit+ (LSK) HSC progenitors while DC and Treg groups received LSK cells along with ex-vivo generated DCs or ex vivo expanded Tregs. On day of HSCT, C57BL/6 recipients received lethal irradiation with 1000 cGy. Day 4 & 7 post HSCT, thymuses of the DC and T reg groups contained 1.5 and 2 fold, respectively, higher number of thymocytes compared to control group. Furthermore, at 4 and 7 days after HSCT, H&E slides of thymuses of showed increased cellularity with medullary lymphoid regeneration in the cohort receiving Tregs. We demonstrate that ex-vivo generated DCs efficiently migrate and home to the thymic medulla and hasten thymic recovery as demonstrated by the higher number of total thymoctyes. The addition of Tregs facilitates engraftment as demonstrated by total number of thymocytes, and lymphoid regeneration in the medullary region of the thymus. Lastly, recipients receiving Tregs were able to facilitate engraftment compared to control group as demonstrated by survival 50% and 0%, respectively (p=0.04).
A novel approach to deplete antigen-specific T cells (145.45)
Authors: Lee Sang Chul , Lee Sun Kyoung , Kim Eun Hwa , Kim Hye Jung , Cho Hong Rae , Kwon ByungSuk 
Published: January 2023

Abstract
CD137 is expressed on activated T cells and is believed to be a reliable surrogate marker for antigen-specific T cells. In this study, we examined the possibility for toxin-conjuated anti-CD137 mAb to kill CD137-expressing T cells. Saporin or doxorubicin was conjugated to anti-CD137 mAb. The efficacy of toxin-conjugated anti-CD137 mAb was examined in vitro and in vivo. First, we observed that fluorescence-conjugated anti-CD137 mAb was internalized into activated CD4+ T cells and CD8+ T cells within 4 hrs after its treatment as well as cell lines that constitutively express CD137. We next treated primary T cells with toxin-conjugated anti-CD137 mAb, following their activation with anti-CD3 mAb. Saporin- or doxorubicin-conjugated anti-CD137 mAb induced apoptosis in a majority of CD4+ T cells and CD8+ T cells within 48 hrs after its treatment, compare with control antibodies. We further confirmed the specificity of toxin-conjugated anti-CD137 mAb showing that only T cells that expressed CD137 underwent apoptosis by staining with toxin-FITC-anti-CD137 mAb conjugates. Finally, we found that toxin-conjugated anti-CD137 mAb was able to delete alloreactive T cells in vivo and prevent aGVHD in animal model. Our results indicate that CD137-targeted delivery of toxin is a good strategy to delete antigen-specific T cells. This approach may be useful for the prevention of rejection after transplantation and treatment of autoimmune diseases.
Donor-specific B cell quiescence following desensitization and transplantation (145.7)
Authors: Jackson Annette , Montgomery Robert 
Published: January 2023

Abstract
Transplantation improves the health and quality of life for patients suffering from renal failure, but for many, antibodies specific for HLA antigens create a substantial barrier. Our center has developed a desensitization protocol to remove HLA-specific antibodies and successfully transplant these sensitized patients. This protocol involves alternate day plasmapheresis, intravenous immunoglobulin (IvIg), and immunosuppressants. We use a Luminex assay to detect HLA-specific antibody and developed a flow cytometric technique using HLA tetramer molecules to quantitate HLA-specific B cells. Following desensitization and transplantation, we observe a sustained loss of donor-specific HLA antibodies, while antibodies specific for 3rd party HLA return to pre-treatment levels. Interestingly, B cells specific for donor-specific HLA persist. We hypothesize that transplantation in the absence of inflammation, due to continued desensitization treatment, allows for the induction of B cell anergy toward donor-HLA. We have isolated HLA-specific B cells post-transplant from desensitized patients using HLA tetramers and performed in vitro cultures for 10-12 days using media containing CD40L, IL2, IL21, IL10, and CpG. B cells specific for donor HLA did not differentiate into antibody secreting cells, while B cells specific for 3rd party HLA did. Further research is underway to understand the mechanisms involved in keeping donor-specific B cells quiescent in these patients post-transplant.
IL-17 promotes the conversion of normal neutrophils to PMN-I, an immunostimulating subset of neutrophils (34.14)
Authors: Inatsu Akihito , Yoshida Shohei , Asai Akira , Kobayashi Makiko , Herndon David , Suzuki Fujio 
Published: January 2023

Abstract
Neutrophils (PMN) influenced by Th1 cytokines or Th17 pathway are essential effector cells in host’s anti-Candida resistance. However, the properties of PMN influenced by IL-17 remain unclear. IL-17 is a cytokine produced by Th17 cells. In this paper, PMN-I with the abilities to kill Candida albicans were shown to be generated from normal neutrophils (PMN-N) after stimulation with IL-17. PMN were considered to be PMN-I when resident Mϕ or naive T cells transwell-cultured with PMN samples were converted to M1Mϕ (CCL3+ IL-10- Mϕ) or Th1 cells (IFN-γ+ IL-4- T cells). PMN (1 × 105 cells/ml), isolated from peripheral blood of healthy donors, were cultured with rIL-17 (0.1 to10 ng/ml) for 9 h. Thereafter, these PMN were transwell-cultured for 9 h with resident Mϕ or T cells syngeneic to PMN donors (1 × 106 cells/ml, lower chamber). Cells in the lower chamber were re-cultured for 24 to 48 h, and culture fluids obtained were assayed for M1Mϕ markers (CCL3 and IL-10) or Th1 cell markers (IFN-γ and IL-4) by ELISA. In the results, M1Mϕ were generated from resident Mϕ transwell-cultured with IL-17-stimulated PMN. Also, Th1 cells were generated from naive T cells transwell-cultured with IL-17-stimulated PMN. These results indicate that IL-17 stimulates the neutrophil conversion from PMN-N to PMN-I.
Toll-like receptor 4 (TLR4) and interferon-gamma (IFN-r) are required for HMGB1-induced TNF release from macrophages. (34.18)
Authors: Yang Huan , Rosas Mauricio , Ochani Mahendar , Li Jianhua , Lu Ben , Olofsson Peder , Chavan Sangeeta , Tracey Kevin 
Published: January 2023

Abstract
High mobility group box 1 (HMGB1) has been implicated as a cytokine mediator in the pathogenesis of inflammatory diseases (Yang et al. BBA, 2009). To study mechanisms of HMGB1 action, we produced mammalian HMGB1, devoid of bacterial products, and examined receptor signaling for HMGB1 mediated macrophage cytokine release. HMGB1 induced significant TNF release in macrophages from TLR2 KO, RAGE KO and wild type (WT) mice (n = 4-5 experiments). HMGB1 induced TNF release was completely abolished in TLR4 KO macrophages as compared to WT. Interestingly, we observed that HMGB1 induced TNF mRNA expression, but not TNF protein release, from TLR4 KO mouse macrophages. Pre-treatment of TLR4 KO macrophages with IFN-r restored HMGB1-induced TNF protein release. Thus, our results indicate that TLR4 is required for HMGB1-mediated cytokine release from macrophages, and that IFN-r can restore HMGB1-induced TNF release in TLR4 KO macrophages. (supported in part by grant from NIH, NIGMS, to KJT).
Characterization of the role of indirect TRAF6 association in CD40 signaling (34.2)
Authors: Decker Dima , Bishop Gail 
Published: January 2023

Abstract
CD40 is a member of the TNFR superfamily expressed on the surface of B cells. The activation of CD40 by its ligand CD154 results in signaling pathways that are of major importance for the activation of B lymphocytes. CD40 lacks direct kinase activity; therefore TNFR-associated factors (TRAFs) are adapter proteins which initiate CD40-mediated signaling by associating with its cytoplasmic (CY) domain. One of these proteins, TRAF6, promotes CD40-mediated NF-κB, JNK and ERK activation. Interestingly, previous work has shown that although TRAF6 binds the CD40 CY domain, and this binding is required for a subset of CD40-mediated functions, TRAF6 can also contribute to CD40 signaling without direct receptor association. To understand the potential regulatory functions mediated by CY TRAF6, we utilized a TRAF6 mutant that cannot bind CD40 (TRAF6ΔC). Expression of this mutant in TRAF6-/- B cells showed that TRAF6 binding was not needed to induce CD40-mediated NF-κB activation. Our results indicated that cytoplasmic signaling of TRAF6 without direct association to CD40 was also sufficient for AKT, p38 and TAK1 activation. Ongoing studies probe additional signaling pathways, and seek to determine the detailed mechanism used by TRAF6 to indirectly mediate CD40 effects.
Anti-inflammatory property of the cannabinoid receptor-2-selective agonist in spinal cord injury (35.11)
Authors: Adhikary Sabina , Hongbo Li , Skarica Mario , Tuma Ronald , Ganea Doina 
Published: January 2023

Abstract
Recently cannabinoids are being studied in treatment of various animal models of CNS disorders such as MS, AD, PD and stroke. They are also being used in treating neuropathic pain in patients with spinal cord injury (SCI). Two cannabinoid receptors have been cloned; CB1, mainly expressed in the CNS and CB2, predominantly expressed in the periphery including immune cells. Previous studies from our laboratory showed that treatment with the CB2 specific agonist O-1966 improved recovery of motor and bladder function in mouse model of acute spinal cord injury. In SCI, increased infiltration and activation of inflammatory immune cells that follow the initial injury exacerbate neuronal damage. In this study we analyzed expression of inflammatory molecules that serve as markers for activation and infiltration of immune cells and their modulation by the CB2 agonist treatment. A murine thoracic spinal cord contusion model of SCI was used and spinal cords were analyzed for expression of various cytokines and chemokines. We found suppression of a number of molecules in spinal cords that were subjected to the CB2 agonist treatment. There was decreased expression of the CXCL family chemokine members CXCL1, 2, 3, 9 and 11, the CC family chemokine members CCL 8, 11, 20, T cell activation cytokines: IFN-γ, IL-23, IL-22 and some of the Toll-like receptors such as TLR1, 4, 6, and 7. Thus, it appears that CB2 agonist treatment may aid in recovery in acute SCI via its immunomodulating effects.
An essential function of FADD in hematopoietic stem cells and progenitors (36.10)
Authors: Zhang Jianke , Rosenberg Stephen 
Published: January 2023

Abstract
Signal transduction mediated by FADD represents a paradigm of co-regulation of both apoptosis and proliferation. Death receptors signal through FADD to activate the downstream caspase 8, and are required for homeostasis in the immune system, yet dispensable during embryonic development. In contrast, a FADD deficiency results in embryonic lethality. In previous studies, a lack of FADD in embryonic stem cells led to severe defects in lymphocyte development. However, conditional deletion of FADD following lymphoid lineage commitment still allows for the generation of T and B cell compartments. Whereas Fas-mediated apoptosis is blocked, a lymphoproliferation disease is lacking in lymphocyte-specific FADD-deficient mice due in part to defective lymphocyte activation. Recent studies indicated that a loss of Fas in dendritic cells is sufficient to cause lymphoproliferation diseases, while the impact of a FADD deficiency in non-lymphiod cells has not been determined. The current study analyzed the effect of simultaneous deletion of FADD in multiple cell types in adult mice by using the IFN-inducible MX1-Cre transgene. Unlike Fas deficient mice, the resulting FADD mutant mice do not develop lymphoproliferation diseases. However, the data demonstrated that FADD plays a critical role in the differentiation and maintenance of hematopoietic stem cells and progenitors.
B cell lineage progression and identity are impeded synergistically in EBF1 and Runx1 haploinsuficient mice (36.13)
Authors: Lukin Kara , Fields Scott , Guerrettaz Lisa , Lopez Desiree , Mansson Robert , Cherrier Marie , Cambier John , Feeney Ann , Sigvardsson Mikael , Hagman James 
Published: January 2023

Abstract
The transcription factors Early B cell factor 1 (EBF1) and Runx1 are essential for B cell development. B lymphopoiesis is arrested at an early state and hematopoiesis is ablated in the absence of EBF1 and Runx1, respectively. Previously, we demonstrated synergistic activity of EBF1 and Runx1 in the activation of the B cell-specific gene mb-1(Cd79a). To identify cooperative functions of these factors in vivo, we generated Ebf(Ehet)Runx(Rhet)-double haploinsufficient(ERhet) mice. Significant compound effects were observed in ERhet mice. B cell numbers in the bone marrow and spleen were reduced greatly. Generation of pre-B and immature B cells in ERhet mice is impeded by: 1) reduced frequencies of Ig light chain gene rearrangements and 2) significant alterations in B cell-specific gene expression. Notably, repression of c-kit and activation of Aiolos were delayed. Interestingly, a high percentage of pro- and pre-B cells from ERhet mice expressed the NK cell markers NK1.1, CD160 and 2B4. Co-expressions of these NK cell markers with genes indicative of B cell commitment was demonstrated using multiplex, single cell PCR. Retroviral complimentation of Ebf1 and Runx1 deficiencies eliminated the promiscuous expression of NK cell genes in ERhet pro-B cells. Thus, appropriate dosage of Ebf1 and Runx1 is necessary for efficient activation of the B cell-specific program and suppression of lineage inappropriate genes. Our data solidify EBF1’s role in controlling B cell lineage commitment.
Identifying chemokine receptor signals required for thymic settling (36.26)
Authors: Zlotoff Daniel , Sambandam Arivazhagan , Logan T. , Bell J. , Schwarz Benjamin , Bhandoola Avinash 
Published: January 2023

Abstract
T cell generation requires the recruitment of bone marrow derived hematopoietic precursors to the thymus via the bloodstream. The chemokine receptor CCR9 and the selectin ligand PSGL-1 each independently support progenitor recruitment to the unirradiated thymus, but progenitors lacking each are not restricted from thymic entry. Hence, additional molecules are likely at work. We now show that the chemokine receptor CCR7 is also involved in this process, as CCR7-/- progenitors are impaired in thymic settling. Furthermore, mice lacking both CCR7 and CCR9 have severe reductions in the number of early intrathymic progenitors, and in competitive assays CCR7-/-CCR9-/- progenitors are almost completely restricted from thymic settling. The compensatory proliferation of rare intrathymic progenitors can allow CCR7-/-CCR9-/- thymi to achieve near-normal cellularity despite severely impaired settling by circulating progenitors. These studies, however, focused on the signals used in unirradiated mice. The mechanisms involved in reconstituting a lethally-irradiated thymus remain poorly defined. We found that during a brief period following irradiation, CCR7-/-CCR9-/- cells are now capable of thymic setttling. Together, these observations illustrate the critical role of chemokine receptor signaling in thymic settling and help to clarify the cellular identity of the physiologic thymic settling progenitors.
FoxN1 in K14 promoter-driven epithelium is required for generation and maintenance of 3D-thymus medulla and preventing nude phenotype in the skin (36.33)
Authors: Guo Jianfei , Rahman Moshiur , Zhang Shuangmin , Zhang Zhijie , Tvinnereim Amy , Su Dong-Ming 
Published: January 2023

Abstract
An organized 3D thymic epithelial cell (TEC) meshwork is crucial for T-lymphocyte development. Expansion of thymic epithelial cystic cavities represents disruption of this 3D-structure. Abnormal culture, lacking lympho-stromal interactions, thymic aging, and gene mutation induce 2D-thymus cysts. Since germline FoxN1 gene mutation develops a 2D-cystic thymic rudiment, while abnormal culture caused 2D-thymus cyst-lining was reported to be non-FoxN1-dependent, it is unclear whether loss of FoxN1 promotes generation of thymic cysts, whether FoxN1 regulates maintenance of the 3D-thymus structure. Using loxP-floxed FoxN1 mouse model, we demonstrated that deletion of FoxN1 in K-14 promoter-driven epithelium induced loss of 3D-thymus medullary structure by producing a large number of alveolus-like 2D-epithelial cysts. The cyst-lining epithelium showed immature TEC phenotype by expressing Cld3,4 and K8, but low levels of MHC-II and K5. These 2D-thymus cysts expanded with ages, associated with reduced UEA-1+ and Aire+ TECs, and FoxN1 mutant Cld3,4+ TECs cannot develop mature medullary TECs. Meanwhile, K14-specific FoxN1 deletion sufficiently induced hair follicle defect and caused FoxN1-null nude phenotype in the skin, but did not cause athymia. These findings provide new insight into gene regulation on 3D-thymus epithelial structure and separate roles of FoxN1 in the thymus and skin. Supported by the NIH grants (R01AI081995, R21AG031880, and R21AI079747) to D-M S.
Cbl Inhibits Vav-1-Independent T Cell Differentiation (36.56)
Authors: Chiang Jeffrey , Hodes Richard 
Published: January 2023

Abstract
Cbl, an E3 ubiquitin ligase, negatively regulates signal transduction events involved in thymic development. Most recently, we reported that inactivation of Cbl rescues the defect of T cell development in mice expressing a mutant SLP-76 that lacks the ability to bind Vav. The defect in T cell development in these SLP-76 mutant mice is similar to that of Vav1 deficient mice, marked by a block at the DN3 stage. It was therefore possible that Cbl inactivation facilitates T cell development through a Vav signaling pathway independent of SLP-76. To assess this possibility, we generated Cbl-/-Vav1-/- double knockout mouse and hypothesized that Cbl inactivation would not be able to reverse the defects of T cell development in Vav1-/- mice. Unexpectedly, the inactivation of Cbl rescued T cell development of Vav1-/- mice. Rescued development in Cbl-/-Vav1-/- DP thymocytes is associated with enhanced tyrosine-phosphorylation of signaling molecules, including Vav2, PLC-gama1 and ERKs in response to TCR stimulation. Therefore, Cbl normally inhibits a T cell differentiation pathway which is independent of Vav-1. The role of Vav2 and other components of this pathway remain to be elucidated.
Expression of CD38 during ontogeny of murine B cells. (36.59)
Authors: Romero-Ramirez Hector , Pelayo-Camacho Rosana , Lopez-Santiago Ruben , Santos-Argumedo Leopoldo 
Published: January 2023

Abstract
CD38 is a 45 KD transmembrane protein, expressed by immature and mature lymphocytes. Agonistic antibodies directed to this molecule induce several biological responses: cellular proliferation, protein phosphorylation, intracellular Ca2+ mobilization, rescue from and induction of apoptosis. CD38 ligation with a mAb anti-CD38 (NIM-R5) induces apoptosis of the murine pro-B cell line (Ba/F3); this phenomenon depends on tyrosine kinases activation and the MAP kinase ERK. The expression and function of CD38 during B-cell ontogeny has been poorly analyzed in mice. We analyzed the expression of CD38 during the ontogeny of B cells in murine bone marrow. Bone marrow cells from C57BL/6J mice were stained with antibodies against: CD19, CD45R, IgM, CD43 and CD38. The samples were captured in a Beckman coulter’s CyAn flow cytometer and each subpopulation was analyzed with FlowJo v.7.5 software. CD38 is expressed from the preproB stage. ProB, preB and immature B cells from murine bone marrow were all positive for the expression of CD38, but immature B cells had the highest fluorescence intensity. The results suggest that CD38 may play a role during the ontogeny of murine B cells. Then, the next step is to analyze whether CD38 ligation on these subpopulations, induces proliferation, maturation or apoptosis.