bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adhesive and/or Signaling Functions of CD44 Isoforms in Human Dendritic Cells
Authors: Haegel-Kronenberger Hélène , de la Salle Henri , Bohbot Alain , Oberling Francis , Cazenave Jean-Pierre , Hanau Daniel 
Published: December 2022

AbstractThe regulation and function of the CD44 family of surface glycoproteins were investigated in human monocyte-derived dendritic cells (DCs). Variant CD44 isoform transcripts encoding exons v3, v6, and v9 are differently regulated during the differentiation of monocytes into DCs. TNF-α treatment, which induces the maturation of DCs, up-regulates the expression of all v3-, v6-, and v9-containing isoforms examined. CD44 molecules are involved in the adhesion of DCs to immobilized hyaluronate (HA), and v3- and v6-containing variants participate in this function, whereas anti-CD44v9 mAbs were unable to inhibit DC adhesion to HA. The consequences of ligand binding to CD44 were examined by culturing DCs on dishes coated with HA or various anti-CD44 mAbs. HA, the anti-pan CD44 mAb J173, and mAbs directed against v6- and v9-containing (but not v3-containing) isoforms provoked DC aggregation, phenotypic and functional maturation, and the secretion of IL-8, TNF-α, IL-1β, and granulocyte-macrophage CSF. In addition, IL-6, IL-10, and IL-12 were released by DCs stimulated with either J173 or HA, although these cytokines were not detected or were found only at low levels in the culture supernatants of DCs treated with anti-CD44v6 or anti-CD44v9 mAbs. Our study points to distinct capacities of the v3-, v6-, and v9-containing isoforms expressed by human DCs to mediate cell adhesion to HA and/or a signal inducing DC maturation and the secretion of cytokines.
The Regulation of CD95 Ligand Expression and Function in CTL
Authors: Li Jie-hui , Rosen Dalia , Ronen Denise , Behrens Christian K. , Krammer Peter H. , Clark William R. , Berke Gideon 
Published: December 2022

AbstractPrevious studies with CTL lines and CTL hybridomas have suggested that functional CD95 (APO-1/Fas)-ligand (CD95L) expression on effector CTLs is a consequence of specific CTL-target recognition and TCR triggering of newly transcribed CD95L. Such a control on the expression of CD95L could provide a double safeguard for killing only cognate target cells. Here the regulation of CD95L expression and function was tested in in vivo primed, alloreactive peritoneal exudate CTL (PEL) from perforin-deficient (P0) mice. CD95L-based, PEL-mediated cytotoxicity was blocked by brefeldin A, an inhibitor of intracellular protein transport, but not by the protein synthesis inhibitor emetine, the immunosuppressive drug cyclosporin A, or the DNA transcription inhibitor actinomycin D. CD95L mRNA transcripts in freshly isolated PEL were shown by RT-PCR; CD95L surface expression was evident by staining with Fas-Fc as well as CD95L Abs. Undiminished CD95L expression and cytocidal activity were found in PEL incubated for 48 h in culture, without adding Ag, mitogen, or cytokines. PEL expressed functional CD95L, yet exhibited target cell-specific killing, except when encountering high CD95-expressing cells. The results indicate that PEL use CD95L probably expressed in the Golgi and/or on the cell surface and do not require newly transcribed CD95L upon target cell conjugation. Hence the TCR-triggered recruitment of preformed CD95L, rather than its biosynthesis, controls CD95L-based specific lysis induced by CTL.
TGF-β1 Somatic Gene Therapy Prevents Autoimmune Disease in Nonobese Diabetic Mice
Authors: Piccirillo Ciriaco A. , Chang Yigang , Prud’homme Gérald J. 
Published: December 2022

AbstractNonobese diabetic (NOD) mice develop insulitis and diabetes through an autoimmune process. Since TGF-β1 down-regulates many immune responses, we hypothesized that TGF-β1 could prevent disease in NOD mice and that there would be several advantages to cytokine delivery by a somatic gene therapy approach. We opted for i.m. injection of a naked plasmid DNA expression vector encoding murine TGF-β1 (pCMV-TGF-β1). Treatment with pCMV-TGF-β1 resulted in the retention and expression of the vector in muscle cells, associated with a considerable elevation in the plasma levels of TGF-β1, that was not observed in control vector-treated mice. The levels of TGF-β1 produced were sufficient to exert immunosuppressive effects. Delayed-type hypersensitivity responses were suppressed, and autoimmunity-prone NOD mice were protected from insulitis and diabetes in models of cyclophosphamide-accelerated and natural course disease. In pCMV-TGF-β1-treated mice, pancreatic IL-12 and IFN-γ mRNA expression was depressed, and the ratio of IFN-γ to IL-4 mRNA was decreased, as determined by semiquantitative reverse-transcription PCR. In contrast, NOD mice injected with a vector encoding the proinflammatory cytokine IFN-γ developed diabetes earlier. Intramuscular administration of cytokine-encoding plasmid vectors proved to be an effective method of cytokine delivery in these mice, and altered autoimmune disease expression.
Normal Thymic Selection of TCR Transgenic CD4 T Cells, but Impaired Survival in the Periphery Despite the Presence of Selecting MHC Molecules
Authors: Barthlott Thomas , Wright Rebecca J. , Stockinger Brigitta 
Published: December 2022

Abstract
In this paper, we investigate selection in the thymus and survival in the periphery of CD4 T cells, which carry a major histocompatibility class II-restricted transgenic TCR (A18 TCRtg) specific for a natural self Ag, the fifth component of complement (C5). A18 TCRtg thymocytes develop normal numbers of CD4 single-positive (SP) thymocytes, but do not show pronounced overselection as do some other TCR transgenic strains. CD4 SP cells are mature as judged by termination of CD8 synthesis, resistance to cortisone, and functional competence. The kinetics of positive selection, determined by BrdU labeling, are very fast. CD4 SP thymocytes are demonstrable within 2 days of labeling, and within 8 days after labeling a large proportion (20%) of lymph node T cells are recent thymic emigrants. The high number of recent thymic emigrants suggests rapid turnover of CD4 T cells in the periphery, which was confirmed by thymectomy and determination of CD4 T cell life spans. A18 TCRtg T cells have a t1/2 of ∼6 wk, despite the presence of selecting MHC molecules. This explains the failure to accumulate high numbers of peripheral T cells and suggests that the MHC-bound ligand(s) responsible for initiating survival signals is limiting for the selection and maintenance of A18 transgenic CD4 T cells.
Localization of Splenic B Cells Activated for Switch Recombination by In Situ Hybridization with Iγ1 Switch Transcript and Rad51 Probes
Authors: Peakman Marie-Claire , Maizels Nancy 
Published: December 2022

AbstractB cells are activated for switch recombination by signals from Th cells, but the site at which this first occurs in vivo has yet to be identified. By in situ hybridization of splenic sections using riboprobes specific for the Iγ1 switch transcript and Rad51 mRNA, we have visualized B cells that are newly activated for switch recombination and characterized the spatial and temporal patterns of Iγ1 and Rad51 mRNA expression. Within 2 days after immunization with (4-hydroxy-3-nitrophenyl)acetyl-chicken gamma-globulin, expression of Iγ1 switch transcripts and Rad51 mRNA was evident and was localized to B220+ B cells clustered within the T cell-rich periarteriolar lymphoid sheath (PALS) and surrounding follicles. By Ab staining, we have shown previously that cells switching from IgM to IgG expression can be visualized at 3 to 5 days postimmunization and colocalize to clusters of Rad51+ cells. Hybridization of adjacent sections with probes for Cμ and Cγ1 mRNA now shows that switching from μ to γ expression occurs within Rad51+Iγ1+ regions of the PALS and peaks between days 3 and 5. Colocalized expression of Iγ1 and Rad51 transcripts was observed from days 2 through 12 of the immune response. Iγ1 and Rad51 transcripts were down-regulated but still detectable at 12 days postimmunization, when they were evident in peanut agglutinin-positive germinal center B cells. Taken together, these observations show that B cells are first activated for switch recombination in the T cell-rich PALS.
Definition of Natural T Cell Antigens with Mimicry Epitopes Obtained from Dedicated Synthetic Peptide Libraries
Authors: Hiemstra Hoebert S. , van Veelen Peter A. , Schloot Nanette C. , Geluk Annemieke , van Meijgaarden Krista E. , Willemen Sabine J. M. , Leunissen Jack A. M. , Benckhuijsen Willemien E. , Amons Reinout , de Vries René R. P. , Roep Bart O. , Ottenhoff Tom H. M. , Drijfhout Jan W. 
Published: December 2022

AbstractProgress has recently been made in the use of synthetic peptide libraries for the identification of T cell-stimulating ligands. T cell epitopes identified from synthetic libraries are mimics of natural epitopes. Here we show how the mimicry epitopes obtained from synthetic peptide libraries enable unambiguous identification of natural T cell Ags. Synthetic peptide libraries were screened with Mycobacterium tuberculosis-reactive and -autoreactive T cell clones. In two cases, database homology searches with mimicry epitopes isolated from a dedicated synthetic peptide library allowed immediate identification of the natural antigenic protein. In two other cases, an amino acid pattern that reflected the epitope requirements of the T cell was determined by substitution and omission mixture analysis. Subsequently, the natural Ag was identified from databases using this refined pattern. This approach opens new perspectives for rapid and reliable Ag definition, representing a feasible alternative to the biochemical and genetic approaches described thus far.
Cloning, Structure, and Function of Two Rainbow Trout Bf Molecules
Authors: Sunyer J. Oriol , Zarkadis Ioannis , Sarrias Maria Rosa , Hansen John D. , Lambris John D. 
Published: December 2022

AbstractThe factor B (Bf) and C2 complement genes are closely linked within the MHC class III region and are thought to have arisen by gene duplication from a single gene encoding an ancestral molecule; the animal phyla in which this duplication event took place is unknown. Two teleost fish, (zebrafish and medaka fish) have each been shown to possess only a single molecule that shows an equivalent degree of similarity to mammalian Bf and C2. In contrast, here we present the characterization of two factor B molecules (Bf-1 and Bf-2) in another teleost fish (the rainbow trout) that are about 9% more similar to mammalian factor B than C2, yet play a role in both alternative and classical pathways of complement activation. The full lengths of Bf-1 and Bf-2 cDNAs are 2509 and 2560 bp, respectively, and their deduced amino acid sequences are 75% identical. Both trout Bf genes are mainly expressed in liver and appear to be single-copy genes. The isolated Bf-1 and Bf-2 proteins are able to form the alternative pathway C3 convertase and are cleaved (in the presence of purified trout C3, trout factor D, and Mg2+EGTA) into Ba- and Bb-like fragments in a manner similar to that seen for mammalian factor B. The most remarkable feature of trout Bf-2 is its ability to restore the hemolytic activity of trout Bf-depleted serum through both the alternative and classical pathways; whether Bf-1 possess similar activity is unclear at present.
Blockade of CTLA-4 Enhances Host Resistance to the Intracellular Pathogen,Leishmania donovani
Authors: Murphy Michaela L. , Cotterell Sara E. J. , Gorak Patricia M. A. , Engwerda Christian R. , Kaye Paul M. 
Published: December 2022

AbstractCTLA-4 has recently been shown to act as a negative regulator of T cell activation. Here we provide evidence that blockade of CTLA-4 can result in enhanced host resistance to an intracellular pathogen. The administration of anti-CTLA-4 mAb 4F10 to BALB/c mice, 1 day following infection with Leishmania donovani, enhanced the frequency of IFN-γ and IL-4 producing cells in both spleen and liver, and dramatically accelerated the development of a hepatic granulomatous response. The expression of mRNA for the CXC chemokine γIP-10 was also elevated above that seen in control Ab treated mice, and was directly correlated with the frequency of IFN-γ producing cells. In contrast, macrophage inflammatory protein-1α (MIP-1α) and monocyte chemotactic protein-1 (MCP-1) mRNA levels were unaffected by anti-CTLA-4 treatment, suggesting that CTLA-4 blockade may exert selective effects on chemokine expression. These changes in tissue response and cytokine/chemokine production were accompanied by a 50 to 75% reduction of parasite load in the spleen and liver of anti-CTLA-4-treated animals compared to controls. Furthermore, administration of anti-CTLA-4 mAb 15 days after L. donovani infection, when parasite burden is increasing in both organs, also resulted in enhanced resistance. Thus, these studies indicate a potent immunomodulatory and potentially therapeutic role for interventions targeted at CTLA-4.
Dermal Endothelial Cells and Keratinocytes Produce IL-7 In Vivo After HumanSchistosoma mansoniPercutaneous Infection
Authors: Roye Olivier , Delhem Nadirah , Trottein François , Remoué Franck , Nutten Sophie , Decavel Jean-Pierre , Delacre Myriam , Martinot Véronique , Cesbron Jean-Yves , Auriault Claude , Wolowczuk Isabelle 
Published: December 2022

AbstractThe parasite Schistosoma mansoni infects its definitive mammalian host through an obligatory cutaneous penetration. In this work, we studied early immune response following migration of larvae through human skin, the first immunocompetent organ encountered by the parasite. For this purpose we used an experimental model of severe combined immunodeficient mice engrafted with human skin and injected with autologous PBL. Six days after percutaneous infection, we observed an infiltration of lymphocytes within the human skin, predominantly composed of CD4+ T cells. Moreover, among the cytokines potentially present in the infected skin, immunohistochemistry analysis revealed an in vivo expression of IL-7 in the epidermal layers and strikingly at the level of vascular endothelium. Using an in vitro coculture system, we showed that the S. mansoni larvae directly trigger IL-7 production by human dermal microvascular endothelial cells but not by keratinocytes. Finally, measurements of IL-7 concentrations in plasma of 187 S. mansoni-infected individuals showed that the youngest, which are also the most infected, displayed the highest IL-7 levels. Together, these findings describe dermal endothelial cells as a novel source of IL-7, a cytokine particularly important in schistosomiasis.
Functional Dissociation Between Local and Systemic Immune Response During Anti-Melanoma Peptide Vaccination
Authors: Lee Kang-Hun , Panelli Monica C. , Kim Christina J. , Riker Adam I. , Bettinotti Maria P. , Roden Matthew M. , Fetsch Patricia , Abati Andrea , Rosenberg Steven A. , Marincola Francesco M. 
Published: December 2022

Abstract
Peptide vaccination against tumor Ags can induce powerful systemic CTL responses. However, in the majority of patients, no tumor regression is noted. To study this discrepancy, we analyzed CTL reactivity in a melanoma patient (F001) vaccinated with g209-2M peptide, a single residue variant of gp100209–217. G209/g209-2M-reactive CTL were identified in post- but not pre-vaccination PBL. Limiting dilution analysis identified one predominant CTL clone (C1-35), with TCR Vβ6s2, recognizing g209/HLA-A*0201-expressing targets. Additionally, two autologous melanoma lines (F001TU-3 and -4) and 20 separate tumor-infiltrating lymphocyte cultures were generated from a fine needle aspirate of a metastatic lesion progressing after initial response to vaccination. Both F001TU did not express gp100 and were not recognized by C1-35. Loss of gp100 by F001TU correlated with a marked reduction of gp100 expression in the same metastatic lesion compared with prevaccination. Thus, ineffectiveness of C1-35 and tumor progression could be best explained by loss of target Ag expression. Interestingly, 12 of 20 tumor-infiltrating lymphocyte cultures recognized F001TU, but none demonstrated g209/g209-2M reactivity, suggesting a functional dissociation between systemic and local immune response. This study suggests that vaccination effects must be analyzed in the target tissue, rather than in the systemic circulation alone.
Weak Anamnestic Responses of Inbred Mice to Yersinia F1 Genetic Vaccine Are Overcome by Boosting with F1 Polypeptide While Outbred Mice Remain Nonresponsive
Authors: Brandler Patricia , Saikh Kamal U. , Heath David , Friedlander Arthur , Ulrich Robert G. 
Published: December 2022

Abstract
The role of immunity to intracellular Ags in resistance to infection by Yersinia is not well established. The enteropathogenic bacteria Yersinia pseudotuberculosis and Yersinia enterocolitica actively translocate Ags to the cytosol of eukaryotic cells. Whereas Yersinia pestis does not always express the requisite cellular adhesins, results have varied as to whether similar cytosolic translocation of Ags occurs in vitro. We used a genetic vaccine to induce intracellular expression of the fraction 1 (F1) capsular protein of Y. pestis within host mammalian cells and examined the ensuing immune response. The F1 genetic vaccine stimulated only weak CTL responses in BALB/c mice. Substantial Ab responses to the F1 genetic vaccine were obtained in all inbred strains of mice tested, but Ab levels were less than those resulting from vaccination with the F1 polypeptide. In contrast, outbred mice did not respond to the F1 plasmid, suggesting that some inbred mouse strains may exhibit exaggerated responses to plasmid vaccines. A primary immunization with the F1 genetic vaccine followed by a boost with recombinant F1 polypeptide produced a vigorous Ab response from inbred mice that was equivalent to three injections of F1 polypeptide. We conclude that cytosolic expression of the F1 Ag efficiently primes immunity, while secondary exposure to the F1 polypeptide is required for optimal Ab induction.
Soluble CD141–152 Confers Responsiveness to Both Lipoarabinomannan and Lipopolysaccharide in a Novel HL-60 Cell Bioassay
Authors: Yu Weiming , Soprana Elisa , Cosentino Giovanna , Volta Manuela , Lichenstein Henri S. , Viale Giovanna , Vercelli Donata 
Published: December 2022

AbstractCD14 is a pattern recognition receptor involved in the interaction with multiple ligands, including LPS from Gram-negative bacteria and lipoarabinomannan (LAM) from mycobacteria. While the interactions between LPS and soluble CD14 (sCD14) have been analyzed in detail, LAM/CD14 interactions remain uncharacterized due to the lack of suitable functional assays. We describe herein a novel bioassay for the analysis of CD14/ligand interactions. CD14-negative myeloid HL-60 cells up-regulate endogenous CD14 gene expression when stimulated with LPS in the presence of recombinant soluble CD141–348. Using the HL-60 bioassay, we showed that sCD141–348 confers responsiveness not only to LPS, but also to LAM. The response to LAM, but not that to LPS, was highly dependent on LPS binding protein (LBP). The N-terminal half of CD14 was sufficient to mediate HL-60 responses to LAM, since HL-60 cells responded with similar efficiency when stimulated with LAM and LBP in the presence of sCD141–348 or sCD141–152. Thus, the N-terminal 152 amino acids of CD14 contain the site(s) involved in the interaction with LAM and LBP, as well as the residues required for LAM-dependent CD14 signaling.
Ca2+-Dependent Production and Release of IL-8 in Human Neutrophils
Authors: Kuhns Douglas B. , Young Howard A. , Gallin Elaine K. , Gallin John I. 
Published: December 2022

Abstract
IL-8, a potent neutrophil chemoattractant that is elevated about 200-fold in exudative neutrophils isolated from localized inflammatory sites in vivo, is thought to play a major role in recruitment of neutrophils to inflammatory sites. Incubation of peripheral blood neutrophils with thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+-sequestering-ATPase, causes a dose-dependent induction of IL-8 synthesis that continues for up to 8 h. Cycloheximide inhibits the thapsigargin-induced IL-8 production, suggesting the induction of protein synthesis de novo. In addition, Northern blot analysis of mRNA isolated from neutrophils indicates that thapsigargin treatment increases IL-8 mRNA in a time- and dose-dependent manner. Thapsigargin also induces a biphasic rise in the intracellular Ca2+ concentration, [Ca2+]i, which is composed of an initial (within 15 s) EGTA-insensitive elevation in [Ca2+]i, followed by a delayed (2-min) EGTA-sensitive component. Addition of EGTA before thapsigargin inhibited the induction of IL-8 production. Experiments in which EGTA was added at various times after thapsigargin treatment indicated that a sustained Ca2+ influx was required for maximum IL-8 production. Ascomycin and cyclosporin A, inhibitors of the Ca2+-dependent phosphatase, calcineurin, also inhibited thapsigargin-induced IL-8 production. Thus, in neutrophils, a prolonged increase in [Ca2+]i stimulates IL-8 transcription and synthesis, possibly through a calcineurin-dependent pathway.
Human Class I Supertypes and CTL Repertoires Extend to Chimpanzees
Authors: Bertoni Roberto , Sette Alessandro , Sidney John , Guidotti Luca G. , Shapiro Max , Purcell Robert , Chisari Francis V. 
Published: December 2022

AbstractUsing an in vitro peptide stimulation strategy, two chimpanzees that were acutely infected by the hepatitis B virus (HBV) produced peripheral blood CTL responses to several HBV-encoded epitopes that are known to be recognized by class I-restricted CTL in acutely infected humans. One animal responded to three HBV peptides that, in humans, are restricted by HLA-A2; the other animal responded to three peptides that are restricted by HLA-B35 and HLA-B51, members of the HLA-B7 supertype in man. The peptides recognized by each chimp corresponded with the ability of its class I molecules to bind peptides containing the HLA-A2 and HLA-B7 supermotifs. Similar, apparently class I-restricted CTL responses to some of these peptides were also detected in occasional HBV-uninfected chimps. These results demonstrate that the CTL repertoire overlaps in humans and chimps and that the HLA-A2 and HLA-B7 supertypes extend to the chimpanzee. Based on these results, the immunogenicity and efficacy of vaccines designed to induce CTL responses to human HLA-restricted viral epitopes may be testable in chimpanzees.
Cutting Edge: CpG DNA Is a Potent Enhancer of Systemic and Mucosal Immune Responses Against Hepatitis B Surface Antigen with Intranasal Administration to Mice
Authors: McCluskie Michael J. , Davis Heather L. 
Published: December 2022

AbstractMucosal immunity is difficult to induce with subunit vaccines unless such vaccines are administered with a mucosal adjuvant such as cholera toxin (CT); however, CT is toxic in humans. Synthetic oligodeoxynucleotides containing immunostimulatory CpG motifs (CpG) are potent adjuvants for the induction of Th1-like systemic immune responses against parenterally delivered proteins. Here, we show in mice that intranasal delivery of hepatitis B surface Ag, which alone has no effect, elicits good immune responses when given with CpG oligodeoxynucleotides and/or CT. Overall, CpG is superior to CT for the induction of humoral and cell-mediated systemic immunity as well as mucosal immune responses (IgA) at local (lung) and distant (feces) sites. Furthermore, CpG and CT act synergistically, giving stronger responses than those observed with 10 times more of either adjuvant alone. Ab isotypes were predominantly IgG1 (Th2-like) with CT, mixed IgG1/IgG2a (Th0) with CpG, and predominantly IgG2a (Th1-like) with CpG and CT together.