bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estradiol Coupling to Human Monocyte Nitric Oxide Release Is Dependent on Intracellular Calcium Transients: Evidence for an Estrogen Surface Receptor
Authors: Stefano George B. , Prevot Vincent , Beauvillain Jean-Claude , Fimiani Caterina , Welters Ingeborg , Cadet Patrick , Breton Christophe , Pestel Joel , Salzet Michel , Bilfinger Thomas V. 
Published: January 2023

Abstract
We tested the hypothesis that estrogen acutely stimulates constitutive NO synthase (cNOS) activity in human peripheral monocytes by acting on an estrogen surface receptor. NO release was measured in real time with an amperometric probe. 17β-estradiol exposure to monocytes stimulated NO release within seconds in a concentration-dependent manner, whereas 17α-estradiol had no effect. 17β-estradiol conjugated to BSA (E2-BSA) also stimulated NO release, suggesting mediation by a membrane surface receptor. Tamoxifen, an estrogen receptor inhibitor, antagonized the action of both 17β-estradiol and E2-BSA, whereas ICI 182,780, a selective inhibitor of the nuclear estrogen receptor, had no effect. We further showed, using a dual emission microfluorometry in a calcium-free medium, that the 17β-estradiol-stimulated release of monocyte NO was dependent on the initial stimulation of intracellular calcium transients in a tamoxifen-sensitive process. Leeching out the intracellular calcium stores abolished the effect of 17β-estradiol on NO release. RT-PCR analysis of RNA obtained from the cells revealed a strong estrogen receptor-α amplification signal and a weak β signal. Taken together, a physiological dose of estrogen acutely stimulates NO release from human monocytes via the activation of an estrogen surface receptor that is coupled to increases in intracellular calcium.
Thymic Transplantation Across an MHC Class I Barrier in Swine
Authors: Haller Gary W. , Esnaola Nestor , Yamada Kazuhiko , Wu Anette , Shimizu Akira , Hansen Andrew , Ferrara Vincent R. , Allison Kenneth S. , Colvin Robert B. , Sykes Megan , Sachs David H. 
Published: January 2023

Abstract
Thymic tissue transplantation has been performed previously in adult mice to induce donor-specific tolerance across allogeneic and xenogeneic barriers. We have now attempted to extend this technique to a large animal preclinical model and describe here our initial studies of allogeneic thymic transplantation in miniature swine. Two miniature swine were thymectomized before thymic tissue transplantation, and two remained euthymic. Donor thymic tissue was harvested from SLA class I-mismatched juvenile pigs and placed into recipient sternocephalicus muscle, kidney capsule, and omentum. A 12-day course of cyclosporin A was started on the day of transplantation. Allogeneic thymic engraftment could only be achieved in euthymic and not in thymectomized miniature swine using this treatment regimen. Both nonthymectomized animals showed good graft development, with evidence of thymopoiesis, as indicated by positive CD1 and host-type SLA class I immunoperoxidase staining of immature graft-infiltrating cells. Both animals also demonstrated donor-specific T cell hyporesponsiveness, as measured by MLR and cell-mediated lympholysis. The thymic grafts continued to develop despite the appearance of high levels of anti-donor specific cytotoxic IgG Abs. Thus, thymic tissue transplanted across an SLA class I barrier can engraft and support host thymopoiesis in euthymic miniature swine. The presence of the host thymus was required for engraftment. These data support the potential of thymic transplantation as part of a regimen to induce donor-specific tolerance to xenogeneic organ grafts.
Regulation of T Cell Homeostasis by Heparan Sulfate-Bound IL-2
Authors: Wrenshall Lucile E. , Platt Jeffrey L. 
Published: January 2023

Abstract
Although IL-2 is commonly thought to promote proliferation of T lymphocytes, mice deficient in IL-2 exhibit splenomegaly, lymphocytosis, and autoimmunity, suggesting this cytokine may have a prominent role in T cell homeostasis. Since the number of T cells in the bloodstream and lymphoid organs is tightly controlled, it is likely that the availability of IL-2 must also be closely regulated. One mechanism altering the local availability of cytokines is association with heparan sulfate, a glycosaminoglycan found on cell surfaces and within extracellular matrices. Here we show that an association between IL-2 and heparan sulfate localizes IL-2 to lymphoid organs such as the spleen. We also show that IL-2, sequestered in this way, contributes to the activation of T lymphocytes and primes T lymphocytes for activation-induced cell death.
Identification and Functional Characterization of the ζ-Chain Dimerization Motif for TCR Surface Expression
Authors: Bolliger Luca , Johansson Britt 
Published: January 2023

Abstract
We recognized a common dimerization motif between the transmembrane (TM) domain of ζ-chain family members and glycophorin A. We have shown that a glycine within the ζ-dimerization motif is critical for ζ-homodimerization and also for its association with the TCR/CD3 complex. Similarly, two residues within the CD3δγ TM domains have proven to be critical for their interaction with the ζ-homodimer. A three-dimensional homology model of the ζ-chain TM domain highlights potential residues preferentially involved either in the ζ2-CD3 or ζ2-TCRαβ association, confirming our experimental findings. These results indicate that, for symmetrical reasons, the ζ-homodimer participates in the TCR/CD3 complex assembly by interacting with CD3γδ TM domains, thereby masking their degradation signals located in the cytoplasmic tails.
Mycobacterium tuberculosis Inhibits IFN-γ Transcriptional Responses Without Inhibiting Activation of STAT1
Authors: Ting Li-Min , Kim Anne C. , Cattamanchi Ashok , Ernst Joel D. 
Published: January 2023

Abstract
IFN-γ activates macrophages to kill diverse intracellular pathogens, but does not activate human macrophages to kill virulent Mycobacterium tuberculosis. We tested the hypothesis that this is due to inhibition of IFN-γ signaling by M. tuberculosis and found that M. tuberculosis infection of human macrophages blocks several responses to IFN-γ, including killing of Toxoplasma gondii and induction of FcγRI. The inhibitory effect of M. tuberculosis is directed at transcription of IFN-γ-responsive genes, but does not affect proximal steps in the Janus kinase-STAT pathway, as STAT1α tyrosine and serine phosphorylation, dimerization, nuclear translocation, and DNA binding are intact in M. tuberculosis-infected cells. In contrast, there is a marked decrease in IFN-γ-induced association of STAT1 with the transcriptional coactivators CREB binding protein and p300 in M. tuberculosis-infected macrophages, indicating that M. tuberculosis directly or indirectly disrupts this protein-protein interaction that is essential for transcriptional responses to IFN-γ. Gamma-irradiated M. tuberculosis and isolated cell walls reproduce the effects of live bacteria, indicating that the bacterial component(s) that initiates inhibition of IFN-γ responses is constitutively expressed. Although lipoarabinomannan has been found to exert effects on macrophages, it does not account for the inhibitory effects of cell walls. These results indicate that one mechanism for M. tuberculosis to evade the human immune response is to inhibit the IFN-γ signaling pathway, and that the mechanism of inhibition is distinct from that reported for Leishmania donovani or CMV, in that it targets the interaction of STAT1 with the basal transcriptional apparatus.
Ig Heavy Chain Complex-Linked Genes Influence the Immune Response in a Murine Cryptococcal Infection
Authors: Lovchik Julie A. , Wilder Julie A. , Huffnagle Gary B. , Riblet Roy , Lyons C. Richard , Lipscomb Mary F. 
Published: January 2023

Abstract
A murine pulmonary infection with Cryptococcus neoformans (Cne) has been used to determine mechanisms regulating effective T cell-mediated immunity in the lungs. In BALB/c and C.B-17 mice, following intratracheal deposition of Cne, the fungus initially grows rapidly and is then progressively cleared from the lungs. Cne clearance in C.B-17 mice requires CD4 and CD8 T cells, IFN-γ, and NO. Clearance in congenic BALB/c mice proceeds more slowly than in C.B-17 mice, even though the only genetic difference between these strains is at the Ig H chain-containing region of chromosome 12. Examination of the pulmonary immune response in the two strains revealed that both cleared lung Cne by T cell-dependent mechanisms and generated equivalent levels of NO. Furthermore, both strains recruited equal numbers of macrophages, lymphocytes, and neutrophils to the lungs, although BALB/c mice recruited higher numbers of eosinophils. Notably, leukocytes isolated from BALB/c lungs during infection secreted lower levels of IFN-γ and higher levels of the Th2 cytokines IL-4 and IL-5 as compared with lung leukocytes from C.B-17 mice. Furthermore, serum levels of IgM, IgG1, IgG2a, and IgG3 anti-Cne Abs generated during infection were significantly greater in BALB/c mice than C.B-17 mice. These data suggest that although both BALB/c and C.B-17 mice clear pulmonary cryptococcosis through T cell-mediated mechanisms, Ig H chain-linked genes in BALB/c mice are associated with a decreased effectiveness of the host response, which we suggest might influence the balance in Th1/Th2 T cell subset development or increase anti-Cne Abs, or both.
Apoptosis of a Human Melanoma Cell Line Specifically Induced by Membrane-Bound Single-Chain Antibodies
Authors: de Inés Concepción , Cochlovius Björn , Schmidt Stefanie , Kipriyanov Sergey , Rode Hans-Jürgen , Little Melvyn 
Published: January 2023

Abstract
CD28 is a key regulatory molecule in T cell responses. Ag-TCR/CD3 interactions without costimulatory signals provided by the binding of B7 ligands to the CD28R appear to be inadequate for an effective T cell activation. Indeed, the absence of B7 on the tumor cell surface is probably one of the factors contributing to the escape of tumors from immunological control and destruction. Therefore, to increase the immunogenicity of tumor cell vaccines, we have expressed anti-CD3 and anti-CD28 single-chain Abs (scFv) separately on the surface of a human melanoma SkMel63 cell line (HLA-A*0201). A mixture of cells expressing anti-CD3 with cells expressing anti-CD28 resulted in a marked activation of allogeneic human PBL in vitro. The apparent induction of a Th1 differentiation pathway was accompanied by the proliferation of MHC-independent NK cells and MHC-dependent CD8+ T cells. PBL that had been cultured together with transfected SkMel63 tumor cells were able to specifically induce apoptosis in untransfected SkMel63 cells. In contrast, three other tumor cell lines expressing HLA-A*0201, including two melanoma cell lines, showed no significant apoptosis. These results provide valuable information for both adoptive immunotherapy and the generation of autologous tumor vaccines.
Inflammatory Cytokines IL-1α, IL-1β, IL-6, and TNF-α Impart Neuroprotection to an Excitotoxin Through Distinct Pathways
Authors: Carlson Noel G. , Wieggel Whitney A. , Chen Jian , Bacchi Annalisa , Rogers Scott W. , Gahring Lorise C. 
Published: January 2023

Abstract
The proinflammatory cytokines IL-1α, IL-1β, IL-6, and TNF-α are produced within the CNS, and, similar to the periphery, they have pleotrophic and overlapping functions. We have shown previously that TNF-α increases neuronal survival to a toxic influx of calcium mediated through neuronal N-methyl-d-aspartic acid (NMDA) glutamate-gated ion channels. This process, termed excitotoxicity, is a major contributor to neuronal death following ischemia or stroke. Neuroprotection by this cytokine requires both activation of the p55/TNF receptor type I and the release of TNF-α from neurons, and it is inhibited by the plant alkaloid nicotine. Here, we report that other inflammatory cytokines (IL-1α, IL-1β, and IL-6) are also neuroprotective to excessive NMDA challenge in our system. Neuroprotection provided by IL-1 is distinct from TNF-α because it is inhibited by IL-1 receptor antagonist; it is not antagonized by nicotine, but it is inhibited by a neutralizing Ab to nerve growth factor (NGF). Similar to IL-1, IL-6-mediated neuroprotection is also antagonized by pretreatment with IL-1 receptor antagonist and it is not affected by nicotine. However, neutralizing anti-NGF only partially blocks IL-6-mediated protection. These studies support an important role for distinct but overlapping neuroprotective cytokine effects in the CNS.
Involvement of Phosphatidylinositol 3-Kinase in Stromal Cell-Derived Factor-1α-Induced Lymphocyte Polarization and Chemotaxis
Authors: Vicente-Manzanares Miguel , Rey Mercedes , Jones David R. , Sancho David , Mellado Mario , Rodriguez-Frade Jose Miguel , del Pozo Miguel Angel , Yáñez-Mó María , de Ana Ana Martín , Martínez-A. Carlos , Mérida Isabel , Sánchez-Madrid Francisco 
Published: January 2023

Abstract
The role of phosphatidylinositol 3-kinase (PI3-kinase), an important enzyme involved in signal transduction events, has been studied in the polarization and chemotaxis of lymphocytes induced by the chemokine stromal cell-derived factor-1α (SDF-1α). This chemokine was able to directly activate p85/p110 PI3-kinase in whole human PBL and to induce the association of PI3-kinase to the SDF-1α receptor, CXCR4, in a pertussis toxin-sensitive manner. Two unrelated chemical inhibitors of PI3-kinase, wortmannin and Ly294002, prevented ICAM-3 and ERM protein moesin polarization as well as the chemotaxis of PBL in response to SDF-1α. However, they did not interfere with the reorganization of either tubulin or the actin cytoskeleton. Moreover, the transient expression of a dominant negative form of the PI3-kinase 85-kDa regulatory subunit in the constitutively polarized Peer T cell line inhibited ICAM-3 polarization and markedly reduced SDF-1α-induced chemotaxis. Conversely, overexpression of a constitutively activated mutant of the PI3-kinase 110-kDa catalytic subunit in the round-shaped PM-1 T cell line induced ICAM-3 polarization. These results underline the role of PI3-kinase in the regulation of lymphocyte polarization and motility and indicate that PI3-kinase plays a selective role in the regulation of adhesion and ERM proteins redistribution in the plasma membrane of lymphocytes.
Human Transaldolase and Cross-Reactive Viral Epitopes Identified by Autoantibodies of Multiple Sclerosis Patients
Authors: Esposito Maria , Venkatesh Vijay , Otvos Laszlo , Weng Zhiping , Vajda Sandor , Banki Katalin , Perl Andras 
Published: January 2023

Abstract
Multiple sclerosis is mediated by an autoimmune process causing selective destruction of oligodendrocytes. Transaldolase, which is expressed in the brain selectively in oligodendrocytes, is a target of high affinity autoantibodies in serum and cerebrospinal fluid of multiple sclerosis patients. A three-dimensional model of human transaldolase was developed based on the crystal structure of the enzyme from Escherichia coli. To identify immunodominant epitopes, 33 peptides overlapping human transaldolase by 5 amino acids were synthesized. Ab 12484, raised against enzymatically active human transaldolase, recognized antigenic determinants corresponding to linear epitopes (residues 27–31 and 265–290) and α helices (residues 75–98 and 302–329). Four immunodominant peptides harboring charged amino acid residues with topographically exposed side chains were identified by sera from 13 multiple sclerosis patients with predetermined autoreactivity to transaldolase. Autoantibodies binding to the most prominent human transaldolase epitope, between residues 271 and 285, showed cross-reactivity with Epstein-Barr and herpes simplex virus type 1 capsid-derived peptides. Molecular mimicry between immunodominant autoepitopes and viral Ags may be a decisive factor in directing autoimmunity to transaldolase in multiple sclerosis patients.
Involvement of IL-15 in the Pathogenesis of Human T Lymphotropic Virus Type I-Associated Myelopathy/Tropical Spastic Paraparesis: Implications for Therapy with a Monoclonal Antibody Directed to the IL-2/15Rβ Receptor
Authors: Azimi Nazli , Jacobson Steven , Leist Thomas , Waldmann Thomas A. 
Published: January 2023

AbstractHuman T lymphotropic virus type I (HTLV-I) is the causative agent of an inflammatory neurological disease termed HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). An ongoing lymphocyte activation exists in patients with HAM/TSP, which was demonstrated by the spontaneous proliferation of their PBMC ex vivo. It was shown that spontaneous proliferation present in HAM/TSP is due, in part, to an IL-2/IL-2R autocrine loop. However, addition of Abs against IL-2 or IL-2Rα only partially inhibited the spontaneous proliferation. Since IL-15 is a cytokine with similar functional characteristics to those of IL-2, we reasoned that IL-15 might be an additional growth factor that contributes to the spontaneous proliferation observed in HAM/TSP. In this study, we demonstrated that IL-15 mRNA expression was elevated in PBMC obtained from HAM/TSP patients when compared with those of the normal donors. Furthermore, we showed that the addition of blocking Abs against IL-15 or its receptor inhibited the spontaneous proliferation of HAM/TSP PBMC. Addition of Abs directed toward both IL-15 and IL-2, or their receptors, inhibited the proliferation almost completely. These data suggest the existence of two autocrine loops involving IL-15/IL-15R and IL-2/IL-2R, both contributing to the spontaneous proliferation of HAM/TSP PBMC.
Depressed IL-12-Mediated Signal Transduction in T Cells from Patients with Sézary Syndrome Is Associated with the Absence of IL-12 Receptor β2 mRNA and Highly Reduced Levels of STAT4
Authors: Showe Louise C. , Fox Floyd E. , Williams Donna , Au Karen , Niu Zhutian , Rook Alain H. 
Published: January 2023

Abstract
Sézary syndrome (SS) is the leukemic phase of cutaneous T cell lymphoma characterized by the proliferation of clonally derived CD4+ T cells that release cytokines of the Th2 T cell phenotype (IL-4, IL-5, IL-10), whereas Th1 T cell cytokines (IL-2, IFN-γ) are markedly depressed as is expression of IL-12, a pivotal cytokine for Th1 cell differentiation. Normal Th1 cells express both the β1 and β2 chains of the IL-12 receptor (IL-12R) and tyrosine phosphorylate STAT4 in response to IL-12. Th2 T cells express only the IL-12R β1 and thus do not tyrosine phosphorylate STAT4 in response to IL-12. To determine whether SS cells are Th2-like at the level of IL-12 signal transduction, we analyzed RNA from seven patients for the presence of message for the IL-12R β1 and β2 genes using RNase protection assays and assessed whether IL-12 induced tyrosine-phosphorylation of STAT4 by immunoblotting. In PBL from six of seven SS patients tested, β2 message was expressed at low to undetectable levels and its expression could not be stimulated by either IFN-α or IFN- γ, which stimulated β2 expression in control PBL. The absence of β2 expression is further supportive evidence for the Th2 lineage of SS cells. However, unlike normal Th2 cells, SS cells also showed severely reduced levels of STAT4, suggesting that they have a depressed response to any inducer of the STAT4 signal transduction pathway, including IFN-α. This is the first observation linking STAT4 gene expression with a human disease and suggests that dysregulation of STAT4 expression may be significant to the development and/or progression of SS.
Vasoactive intestinal peptide (VIP) up-regulates IL-17 generation by mouse CD4 T cells (100.1)
Authors: Dai Qun , Goetzl Edward J 
Published: January 2023

Abstract
VIP produced by cholinergic and sensory nerves and by T cells affects T cell functions through the constitutively-expressed VPAC1 and inducible VPAC2 G protein-coupled receptors. Transgenic mice overexpressing VPAC2 (TG) selectively on CD4 T cells exhibit increased hypersensitivity and immunoinflammatory responses. Present studies were designed to examine the capacity of the VIP-VPAC2 axis to recruit the Th17 inflammatory subset of CD4 T cells. Splenic CD4 T cells isolated from TG and wild-type (WT) mice were incubated with adherent anti-CD3 and anti-CD28 antibodies and cytokines that initiate Th17 development, without and with IL-23 or VIP. IL-17 generation quantified by ELISA was enhanced significantly by 1μM VIP with the same time-course as for IL-23 over five days. IL-17 generation by CD4 T cells of TG mice was significantly greater than by those of WT mice with and without added VIP. Augmentation of IL-17 generation by both VIP and IL-23 was suppressed similarly by IL-27. Thus VIP may be a neuroalternative endogenous stimulus for Th17 development and recruit Th17 cells independently of IL-23 in inflammatory and autoimmune processes. (NIH grant AI029912)
HMGB1 binds to LPS and transfers it to CD14 (100.12)
Authors: Youn Ju Ho , Oh Young Joo , Kim Ah Reum , Shin Jeon-Soo 
Published: January 2023

Abstract
Lipopolysaccharide (LPS) itself released from Gram-negative bacteria poorly induces biological function because of its poor solubility. With help of LPS-binding protein (LBP), the diffusion of LPS monomers from the aggregates is mediated and transferred to CD14 to induce TLR4-mediated signal pathway. Secreted extracellular high mobility group box-1 protein (HMGB1) from activated monocytes acts as a proinflammatory cytokine and serum concentrations of HMGB1 are increased in patients presenting with sepsis and hemorrhagic shock. However, the exact role in triggering inflammation signal transduction on the immune cell surface membrane by secreted HMGB1 is poorly understood. We first show that HMGB1 could bind to three LPS from E. coli, S. typhi and S. minnesota in a concentration-dependent manner by surface plasmon resonance (SPR) and ELISA assay. LBP could inhibit the binding of HMGB1 to LPS in a dose-dependent manner. HMGB1 bound to diphosphryl lipid A moiety containing 2-keto-3-deoxyoctanate from S. minnesota LPS Re595, but poorly to detoxified LPS without lipid A moiety. In addition, HMGB1 could efficiently transfer LPS to CD14 protein in time-dependent and dose-dependent manners using BODIPY-LPS transfer assay and the native gel mobility shift assay. These results suggest that HMGB1 has a novel role in initiating LPS-mediated signaling by catalyzing movement of LPS monomers from LPS aggregates to cell surface CD14 in addition to the previous report of TLR4 signaling by direct HMGB1-TLR4 binding.
Novel immuno-spin trapping-based assay for the analysis of myeloperoxidase (100.13)
Authors: RAMIREZ DARIO C , GOMEZ-MEJIBA SANDRA E , CORBETT JEAN T , MASON RONALD P 
Published: January 2023

Abstract
Myeloperoxidase (MPO) is an important biomarker of inflammatory diseases. The analyses of MPO in biological samples are based on detection of its peroxidase activity, chloramine formation, and MPO-capture immunoassays. We have developed an immuno-spin trapping (IST)-based approach to determine MPO in biological samples. In this approach,
MPO/H2O2/Cl system produces hypochlorous acid (HOCl);HOCl reacts with proteins forming chloramines;chloramines decay forming protein radicals,protein radicals are trapped by the nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) forming DMPO-protein nitrone adducts, andnitrone adducts are determined using a chemiluminescent direct ELISA with the anti-DMPO antiserum.
We used this assay to quantify MPO in plasma, bronchoalveolar fluid and lung parenchyma of rats exposed to lipopolysaccharide, and compared its sensitivity with a capture-based commercial ELISA kit. Hemoglobin does not interfere and the assay can be used in animal and human samples. The assay has three levels of amplification:
enzymatic formation of HOCl;many DMPO molecules bound per single protein molecule;a sensitive developing system.
The IST-based assay for quantification of MPO will enhance the power of this biomarker for early detection of environmental- and metabolic-induced inflammatory disorders in both experimental and clinical settings. NIH#1K99 ES015414-01