bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro and in vivo secretion of human ISG15, an IFN-induced immunomodulatory cytokine.
Authors: D'Cunha J , Ramanujam S , Wagner R J , Witt P L , Knight E , Borden E C 
Published: December 2022

Abstract
ISG15, a 15-kDa protein of unique primary amino acid sequence, functions intracellularly as a ubiquitin homologue and a cytokine that induces production of IFN-gamma and augments NK/lymphokine-activated killer cell proliferation and function. ISG15 is secreted from monocytes and lymphocytes, and in this study we have characterized in vitro and in vivo production of ISG15 in response to IFN-alphabeta. Low levels of ISG15 were present constitutively in PBMCs; dose-dependent ISG15 synthesis was observed in response to IFN-alpha or IFN-beta, but not IFN-gamma. High m.w. conjugates, present in PBMC extracts constitutively, were enhanced after IFN-alpha or IFN-beta treatment. Metabolic labeling experiments demonstrated that IFN-beta-induced ISG15 was released from primary cultures of peripheral blood CD3+ (including both CD4+ and CD8+ subpopulations). Furthermore, ISG15 was released from viable cell lines of monocyte, T lymphocyte, B lymphocyte, and epithelial origins. Since ISG15 was secreted in response to IFN treatment in vitro, its levels in the serum of healthy human volunteers treated with IFN-beta(ser) were quantitated by asymmetric sandwich ELISA. Both single and multiple doses of IFN-beta(ser) increased serum ISG15 levels significantly (p &lt; 0.01) over baseline. A maximum 7.3-fold enhancement of serum ISG15 was obtained after multiple injections of 8 million units of IFN-beta(ser). Significant change was observed at 24 and 48 h of multiple 0.02-million-unit injections, yielding 1.2- and 1.7-fold increases over basal levels, respectively. These studies suggest that ISG15 is a novel member of the cytokine cascade that is synthesized and released in response to IFN-beta both in vitro and in vivo.
Escherichia coli hemolysin and Staphylococcus aureas alpha-toxin potently induce neutrophil adhesion to cultured human endothelial cells.
Authors: Krüll M , Dold C , Hippenstiel S , Rosseau S , Lohmeyer J , Suttorp N 
Published: December 2022

Abstract
Adhesion of polymorphonuclear leukocytes (PMN) to endothelial cells is an essential step in inflammatory reactions. We characterized the effects of two important bacterial exotoxins, Escherichia coli hemolysin (HlyA) and Staphylococcus aureus alpha-toxin (S. alpha-toxin) on PMN adhesion to cultured HUVEC. Both toxins increased adherence of human PMN to HUVEC in a dose- and time-dependent manner, peaking after 30 min at 0.01 hemolytic units/ml HlyA or 0.5 microg/ml S. alpha-toxin. Pretreatment of HUVEC with anti-P-selectin mAbs or of PMN with anti-CD11b/CD18 mAb reduced HlyA- and S. alpha-toxin-related cell adhesion significantly. Increased P-selectin expression on toxin-treated endothelial cells was demonstrated by cell surface ELISA. Compared with endotoxin, HlyA and S. alpha-toxin did not induce the expression of E-selectin, ICAM-1, or VCAM-1. FACS analysis showed increased CD11b/CD18 expression on HlyA-, but not on S. alpha-toxin-stimulated PMN. Platelet-activating factor, an important costimulatory factor for PMN adhesion and activation, was also active in the exotoxin-stimulated adhesion system, as evidenced by studies using the platelet-activating factor receptor antagonist BN50727. HPLC analysis of endothelial cell extracts confirmed enhanced toxin-mediated PAF synthesis. The capacity of exotoxins to stimulate PMN adhesion to endothelial cells may be relevant in patients with severe local or systemic bacterial infections.
TNF-alpha and IL-1beta selectively induce expression of 92-kDa gelatinase by human macrophages.
Authors: Sarén P , Welgus H G , Kovanen P T 
Published: December 2022

Abstract
Macrophages are present in inflammatory tissue sites where abnormal degradation of the extracellular matrix takes place. To evaluate the potential of macrophages to participate in such matrix destruction, we studied the effects of three cytokines present in inflammatory tissue sites, TNF-alpha, IL-1beta, and IFN-gamma, on the production of three matrix-degrading metalloproteinases, interstitial collagenase, stromelysin, and 92-kDa gelatinase, as well as their natural inhibitor, TIMP-1 (tissue inhibitor of metalloproteinases number 1), by human monocyte-derived macrophages differentiated in vitro. Spontaneous production of interstitial collagenase and stromelysin by these cells was minimal, and was not influenced by the cytokines. In contrast, the cells secreted substantial basal amounts of 92-kDa gelatinase, the secretion of which was stimulated (2- to 15-fold; on average 5-fold) by both TNF-alpha and IL-1beta, while the production of TIMP-1 was unaffected. IFN-gamma suppressed the production of the 92-kDa gelatinase induced by TNF-alpha- and IL-1beta. TNF-alpha and IL-1beta regulated the expression of 92-kDa gelatinase by monocyte-derived macrophages at the pretranslational level. The results show that expression of 92-kDa gelatinase, but not its natural inhibitor TIMP-1, by human tissue-type macrophages is selectively up-regulated by proinflammatory cytokines; which suggests that these cells, when actually present in an inflammatory environment, will actively participate in the destruction of the extracellular matrix.
Bronchoalveolar lavage neutrophilia is associated with obliterative bronchiolitis after lung transplantation: role of IL-8.
Authors: DiGiovine B , Lynch J P , Martinez F J , Flint A , Whyte R I , Iannettoni M D , Arenberg D A , Burdick M D , Glass M C , Wilke C A , Morris S B , Kunkel S L , Strieter R M 
Published: December 2022

Abstract
Obliterative bronchiolitis (OB) is a devastating complication in lung transplantation. We postulated that the pathogenesis of OB is mediated, in part, by neutrophils. We serially collected bronchoalveolar lavage (BAL) fluid from lung transplant recipients. Patients were divided into two groups depending on the presence or absence of OB. Samples from patients who never developed OB were further divided according to whether rejection was present. These samples were labeled healthy or rejection. Samples from patients who developed OB were divided according to whether the sample was obtained before (future OB) or at the time of diagnosis of OB (OB). The OB group, as compared with the healthy and rejection group, had significantly elevated neutrophil counts (3.9 x 10(5) +/- 1.8 x 10(5) vs 0.3 x 10(5) +/- 0.07 x 10(5) and 0.4 x 10(5) +/- 0.1 x 10(5), respectively, p &lt; 0.01 for both) and levels of IL-8 (3131 +/- 1468 pg/ml vs 240 +/- 62 pg/ml and 172 +/- 47 pg/ml, p &lt; 0.01 for both). Furthermore, we demonstrated immunolocalization of IL-8 associated with alpha smooth muscle actin-positive cells in the peribronchial region of OB. To confirm that the IL-8 present in BAL fluid from patients with OB was bioactive, we performed neutrophil chemotaxis experiments that showed that IL-8 accounted for a significant amount of the neutrophil chemotactic activity. We also found a trend toward higher levels of neutrophils and IL-8 in BALs from the future OB as compared with the healthy group (7.1 x 10(4) +/- 4.2 x 10(4) vs 3.4 x 10(4) +/- 0.7 x 10(4) and 500 +/- 306 pg/ml vs 240 +/- 62 pg/ml). In conclusion, we have provided the novel observation that in lung transplant recipients with OB, neutrophilia is present and highly correlated with the presence of IL-8.
Suppression of murine chronic relapsing experimental autoimmune encephalomyelitis by the oral administration of myelin basic protein.
Authors: Meyer A L , Benson J M , Gienapp I E , Cox K L , Whitacre C C 
Published: December 2022

Abstract
Chronic relapsing experimental autoimmune encephalomyelitis (EAE), induced in mice by the injection of myelin basic protein (MBP), is a T cell-mediated autoimmune disease characterized by periods of paralysis and remission. We have shown previously that the oral administration of MBP or MBP peptides renders Lewis rats refractory to EAE. This study was undertaken to examine the conditions necessary to produce oral tolerance in a chronic relapsing model of EAE in B10.PL mice. The optimal tolerizing regimen for the mouse was found to be a single feeding of 20 mg of MBP suspended in PBS. To determine the ability to suppress chronic disease, a range of doses (0.4-100 mg) was administered orally in a single dose before challenge. Larger oral doses (20 or 100 mg) of MBP provided the best protection from EAE, while 0.4 mg exacerbated the clinical course of disease. Secretion of the proinflammatory cytokines, IL-2 and IFN-gamma, were lowest in the group fed 20 mg. A single feeding of MBP before challenge or as late as the first day of clinical signs showed significant protection over the relapsing disease course. Once relapsing EAE was established, multiple oral doses of MBP were required to achieve suppression of clinical signs of disease. These findings suggest that vehicle, dosage, and timing are important considerations in the successful application of oral tolerance strategies for suppression of chronic disease processes.
Genetic bases of human complement C7 deficiency.
Authors: Nishizaka H , Horiuchi T , Zhu Z B , Fukumori Y , Volanakis J E 
Published: December 2022

Abstract
Complement C7 deficiency (C7D) is associated frequently with recurrent bacterial infections, especially meningitis caused by Neisseria meningitidis. We report in this work the molecular bases of C7D in two unrelated Japanese males. We used exon-specific PCR/single-strand conformation polymorphism analysis as a screening step for mutations. Subsequent direct sequencing of the target exons identified homozygous mutations in exon 16 of case 1 and in exon 15 of case 2. The mutation of case 1 was a homozygous T to A transversion at nucleotide 2250, the third nucleotide of the codon TGT for Cys728, leading to a stop codon TGA (C728X). In case 2, a homozygous 2-bp deletion (2137delTG/2138delGT/2139delTG) caused a frameshift, generating a premature termination codon 4 to 6 nucleotides downstream. Family study in case 1 confirmed the genetic nature of the defect. Moreover, we detected a novel polymorphism in intron 11 that presumably is linked to the mutation responsible for C7D in case 1. Our results indicate that the pathogenesis of C7D is heterogeneous like most of the other deficiencies of complement components.
Influence on CD8 of TCR/CD3-generated signals in CTL clones and CTL precursor cells.
Authors: Anel A , Martínez-Lorenzo M J , Schmitt-Verhulst A M , Boyer C 
Published: December 2022

Abstract
Alloreactive CTL clones and naive CTL precursor cells (CTLp) from TCR-transgenic mice were analyzed for their response in total and in TCR-associated kinase activation upon stimulation with the relevant class I allo-APCs. The responses were found to be stronger and more sustained for the CTL clone and CTLp expressing a TCR previously characterized as CD8 coreceptor independent than for the CTL clone and CTLp expressing a TCR characterized as CD8 dependent. Unexpectedly, it was found that also in response to CD3 engagement, total and TCR-associated kinase activation were stronger and more sustained in the CTL clone and CTLp expressing the CD8-independent TCR. In both types of CTL clones, p56(lck) was found associated with the TCR complex, and CD3 components were found associated with CD8 before CD3 engagement. Upon CD3 engagement, ZAP-70 was also found associated with the TCR complex and the kinase activity (p56(lck)) associated with CD8 increased. This increase was more pronounced for the CD8-independent than for the CD8-dependent clone. An increased association of CD3zeta with CD8 was also detected after CD3 engagement for each clone. These data indicate that signals resulting from exclusive CD3 engagement can influence CD8 molecular associations and activate CD8-bound p56(lck). They further suggest that clonal differences exist that influence the efficiency of signaling upon binding of the same CD3 ligand. The observation that this property was shared between independently derived CTL clone and CTLp expressing the same TCR suggests that it may be acquired during repertoire selection.
Oligonucleotide-mediated inhibition of CD28 expression induces human T cell hyporesponsiveness and manifests impaired contact hypersensitivity in mice.
Authors: Tam R C , Phan U T , Milovanovic T , Pai B , Lim C , Bard J , He L 
Published: December 2022

Abstract
Ligation of CD28 provides a costimulatory signal essential for Ag-mediated T cell activation via the TCR. Blocking CD28 ligation can inhibit cytokine expression and elicits a state of T cell hyporesponsiveness. In this study, we examined the effect of inhibiting CD28 expression on in vitro and in vivo T cell responses. To address this, we have synthesized a series of G-rich phosphorothioate oligonucleotides that inhibited activation-induced transcription and cell surface expression of CD28 on human T cells. CD28 blockade was selective, as expression of other activation-induced receptors was unaffected by oligonucleotide treatment. Using strategic changes to base composition, we identified a minimal 12-mer sequence, containing two sets of four contiguous guanosines separated by 3 to 5 bases, which conferred activity in vitro. Furthermore, inhibition of CD28 expression mediated by one representative active oligonucleotide, GR1, resulted in a concomitant dose-dependent diminution of anti-CD3/PMA-induced cytokine (IL-2, IFN-gamma, IL-8) production. Inhibition of IL-2 synthesis was dependent on CD28 expression, as GR1 failed to abrogate activated IL-2 production in a CD28-deficient T cell line, HUT 78. The inhibitory activity of GR1 reduced T cell proliferative responses in MLR and induced Ag-specific T cell hyporesponsiveness to alloantigens. Finally, s.c. administration of GR1 impaired in vivo contact hypersensitivity responses in mice and was associated with substantially decreased CD28 and IFN-gamma mRNA expression in lymph node cells. Collectively, our studies show the tolerogenic potential of oligonucleotide-mediated CD28 inhibition on T cell activation, in vitro and in vivo.
Mapping regions of herpes simplex virus type 1 glycoprotein I required for formation of the viral Fc receptor for monomeric IgG.
Authors: Basu S , Dubin G , Nagashunmugam T , Basu M , Goldstein L T , Wang L , Weeks B , Friedman H M 
Published: December 2022

Abstract
Glycoprotein E (gE) and glycoprotein I (gI) of herpes simplex virus type 1 (HSV-1) form a complex that binds the Fc domain of monomeric IgG. In this study, we used two approaches to map the regions of gI-1 required for formation of the HSV-1 Fc receptor for monomeric IgG. First, we constructed six plasmids encoding gD-1/gI-1 fusion proteins. Each fusion protein contains a large gI-1 peptide inserted into the ectodomain of gD-1. gD-1/gI-1 fusion proteins were coexpressed with gE-1 using a transfection-infection assay in which cells were transfected with individual fusion protein constructs and then infected with a gE+/gI- virus. Cells were then assayed for monomeric IgG binding using immunofluorescence microscopy. Transfection-infection with two of six fusion proteins conferred monomeric IgG binding activity to cells, whereas cells infected with gE+/gI- virus alone failed to bind IgG monomers. The smallest gI-1 peptide to confer monomeric IgG binding activity contained amino acids 43 to 192. To more precisely map the region of gI-1 required for monomeric IgG binding, we constructed a panel of 10 gI-1 linker insertion mutants. Transfection-infection studies identified two mutants containing linker insertions at gI-1 amino acids 128 and 145, which failed to bind monomeric IgG. The other eight mutants demonstrated wild-type IgG binding activity. Taken together, these results indicate that the region of gI-1 between amino acids 128 and 145 is required for formation of the HSV-1 Fc receptor for monomeric IgG.
Analysis of the contact sites on the CD4 molecule with class II MHC molecule: co-ligand versus co-receptor function.
Authors: Huang B , Yachou A , Fleury S , Hendrickson W A , Sekaly R P 
Published: December 2022

Abstract
The CD4 molecule interacts with the alpha2 and beta2 domains of the MHC class II molecules. However, the class II contact sites on CD4 are less clear. Involvement of different regions throughout D1, D2, and D3 domains have been suggested. To further delineate the class II MHC contact sites on CD4, a crystal structure-informed mutagenesis was performed. Alanine scan mutants were generated for exposed residues located throughout D1 and the FG loop of D2, and in the "hinge-like" region, a short and flexible region between D2 and D3. Mutants were tested in a co-ligand (Dd stimulation) and a co-receptor (staphylococcal enterotoxin B stimulation) assay. In the co-ligand assay, TCR and CD4 interact with two distinct ligands (Dd or HLA-DR), while in the co-receptor assay both molecules interact with the same ligand, namely HLA-DR. Results show that residues from both lateral faces of D1 and the FG loop of D2 are implicated in interaction with class II, although a bigger surface of CD4 was involved in co-receptor compared with co-ligand function. The potential involvement of residues on both the top and two side faces of CD4 is consistent with a bivalent model, which involves the interaction between a single CD4 and two class II molecules. Alternatively, our results can be interpreted with a model of a specifically organized CD4 and/or class II oligomerization event. Finally, results from the hinge region mutants revealed a very important role in maintaining the overall structural integrity of CD4, its topology, and function.
Regulation of IL-15 secretion via the leader peptide of two IL-15 isoforms.
Authors: Onu A , Pohl T , Krause H , Bulfone-Paus S 
Published: December 2022

Abstract
The secretion of IL-15, a potent modulator of T, B, and NK lymphocyte functions, is likely to be tightly controlled. Here, we show that human T lymphoblasts transcribe the IL-15 gene and generate an alternative splicing product that codes for the same amino acid composition as the mature IL-15 protein, but produces an IL-15 precursor protein with a shorter signal peptide. Both alternative splicing products are transcribed by non-IL-15-secreting lymphocytes, suggesting that IL-15 secretion is not primarily controlled at the level of transcription. We generated an in vitro system for correlating the expression, translation, and secretion of IL-15 or IL-15-IgG1 fusion protein. This revealed that the two isoforms of IL-15 or a truncated IL-15 variant, both alone and fused to human IgG1, are all transcribed and translated, but not efficiently secreted. After replacing the IL-15 leader peptide with a foreign one, translation and secretion clearly increase. These results suggest that IL-15 is mainly controlled at the level of translation and secretion.
Antigen-driven but not lipopolysaccharide-driven IL-12 production in macrophages requires triggering of CD40.
Authors: DeKruyff R H , Gieni R S , Umetsu D T 
Published: December 2022

Abstract
We demonstrated that two distinct pathways exist for the induction of IL-12 in APC. The first pathway for IL-12 production occurred during responses to T cell-dependent Ags such as OVA and required triggering of CD40 molecules on the APC. IL-12 production in this T cell-dependent system increased in direct proportion to Ag concentration and required TCR ligation but not CD28 costimulation. The second pathway occurred when bacterial products such as LPS or heat-killed Listeria monocytogenes were used to activate macrophages to produce IL-12 in the complete absence of T cells. In this second pathway, IL-12 production was completely independent of CD40 triggering. In both pathways, the presence of IFN-gamma was not required for induction of IL-12 synthesis when splenic adherent cells (SAC) from normal mice were used. However, addition of IFN-gamma to cultures of Th2 T cells and SAC increased IL-12 production two- to fivefold, and addition of rTNF-alpha with IFN-gamma further enhanced IL-12 production. The addition of TNF-alpha in the absence of IFN-gamma, however, had no effect on IL-12 production in the T cell-dependent pathway. Similarly, addition of TNF-alpha in the presence or the absence of IFN-gamma to cultures of LPS or heat-killed Listeria and SAC did not increase IL-12 production, but addition of IFN-gamma alone greatly enhanced IL-12 production, consistent with the idea that bacterial stimuli induce significant quantities of endogenous TNF-alpha production. These results indicate that the requirements for the induction of IL-12 production in T cell-dependent and T cell-independent responses differs mainly with regard to CD40 triggering. Furthermore, these results suggest that IL-12 production can be induced by bacterial products in patients with hyper-IgM syndrome who lack CD40 ligand expression and in those treated with soluble gp39 to interrupt CD40-CD40 ligand interactions.
Neutrophil CD18-dependent arrest on intercellular adhesion molecule 1 (ICAM-1) in shear flow can be activated through L-selectin.
Authors: Gopalan P K , Smith C W , Lu H , Berg E L , McIntire L V , Simon S I 
Published: December 2022

Abstract
Neutrophil emigration through endothelial cells under shear flow involves several adhesion processes including cell rolling, arrest, and transmigration. Rolling is mediated by selectins, while arrest and transmigration both require activated CD18 integrins. One mode of CD18 activation is via selectins expressed on neutrophils and endothelial cells. We have recently reported that cross-linking of L-selectin (CD62L) resulted in the rapid activation of CD18-dependent adhesion. In the current study, we examine whether binding of E-selectin (CD62E) and L-selectin can activate neutrophil CD18-dependent adhesion under shear flow. Human ICAM-1 (CD54) and E-selectin were co-transfected into L cells. Neutrophil capture, rolling, and arrest on these monolayers were quantitated in a parallel plate flow chamber at a wall shear stress of 2.0 dyne/cm2. Under these conditions, E-selectin supported cell capture and rolling on the monolayer, but did not trigger CD18-mediated cell arrest within 200 microm of rolling. However, when neutrophils were treated with anti-L-selectin mAb and cross-linked with a secondary mAb, approximately 50% of the cells arrested within 54 microm. Cell arrest was also observed in response to IL-8 stimulation. A subthreshold level of IL-8 in combination with L-selectin cross-linking potentiated the level of cell arrest due to either stimulus alone. The transition to cell arrest involved both LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18). Blocking either subunit alone failed to reduce arrest, while blocking both molecules with mAbs reduced the number to baseline levels. These data support the conclusion that L-selectin, but not E-selectin, can signal the transition from neutrophil rolling to cell arrest under shear flow.