bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of mouse CD43 in the B cell lineage of transgenic mice causes impaired immune responses to T‐independent antigens
Authors: Ostberg Julie R. , Dragone Leonard L. , Borrello Melinda A. , Phipps Richard P. , Barth Richard K. , Frelinger John G. 
Published: March 2007

AbstractCD43 (leukosialin), a sialylated glycoprotein expressed on the surface of most hematopoietic cells, has been implicated in cell adhesion and signaling. However, its precise physiological function remains unclear. We used mouse CD43 (mCD43)‐immunoglobulin enhancer‐transgenic (TG) mice to study the role of mCD43 in vivo. Previous work revealed that mCD43 expression on mature B cells in these mice resulted in immunodeficiency to T‐dependent (TD) antigens (Ag), possibly by impairing B‐T cell interactions. In the present study we have immunized the TG mice with the T‐independent (TI) Ag fluorescein‐(Fl) lipopolysaccharide (LPS) (TI type 1 Ag) and Fl‐Ficoll (TI type 2 Ag). Surprisingly, the mCD43‐Ig enhancer expressing mice were impaired in their ability to mount humoral responses to both Fl‐LPS and Fl‐Ficoll, and had decreased numbers of cells responding to Ag in vivo. Flow cytometric analysis was performed on peritoneal B‐1 cells, a population which often plays a major role in humoral responses to TI Ag such as bacterial Ag. This analysis revealed similar B220, IgM and CD5 expression patterns for the TG and nontransgenic (NTG) B‐1 cells. In addition, purified peritoneal B‐1 cells from TG and NTG mice were able to respond to LPS. Stimulation of splenic B cells in vitro with Fl‐LPS and Fl‐Ficoll revealed that, in contrast to NTG B cell responses, TG B cell responses could not be enhanced by co‐culture with T cells. However, soluble T cell factor enhancement of the TG B cell responses was normal. These data suggest that the mCD43 expression on B cells may inhibit cell interactions that are important for enhanced TI Ag responses. The anti‐adhesive forces of mucins in general may thus be critical in regulating both TD and TI humoral responses.
Induction of endothelial cell surface adhesion molecules by tumor necrosis factor is blocked by protein tyrosine phosphatase inhibitors: Role of the nuclear transcription factor NF‐xB
Authors: Dhawan Subhash , Singh Sanjaya , Aggarwal Bharat B. 
Published: March 2007

AbstractRecent studies from our laboratory have indicated that protein tyrosine phosphatase (PTPase) inhibitors can down‐modulate the tumor necrosis factor (TNF)‐mediated activation of the nuclear transcription factor NF‐xB in ML‐1a, a monocytic cell line (Singh and Aggarwal, J. Biol. Chem. 1995: 270: 10631). Since TNF is one of the major inducers of various adhesion molecules in human endothelial cells and their expression is known to require the activation of NF‐xB, we examined the effect of PTPase inhibitors on the TNF‐mediated induction of intracellular adhesion molecule (ICAM)‐1, vascular cell adhesion molecule (VCAM)‐1 and endothelial leukocyte adhesion molecule (ELAM)‐1. Like ML‐1a, human dermal microvessel endothelial cells (MVEC) treated with TNF rapidly activated (within 30 min) NF‐xB; this effect was completely abolished by co‐treatment with phenylarsine oxide (PAO), a specific inhibitor of PTPase. The induction of ICAM‐1, VCAM‐1, and ELAM‐1 by TNF in MVEC occurred within 6 h and was also completely down‐regulated by PAO in a dose‐dependent manner. PAO was found to be effective even when added 3 h after TNF, suggesting a rapid mode of action of this inhibitor. Besides PAO, other inhibitors of PTPase, including pervanadate and diamide, also blocked TNF‐dependent NF‐xB activation and induction of all the three adhesion proteins. Consistent with these results, the attachment of monocytes to MVEC was also blocked by the PTPase inhibitors. Thus, overall, our results demonstrate that a PTPase is involved either directly or indirectly in the pathway leading to the induction of endothelial cell adhesion molecules by TNF. Because of their role in cell adhesion, PTPase may provide a novel target of drug development for treatment of inflammation, atherogenesis, and tumor metastasis.
The migratory behavior of murine CD4+ cells of memory phenotype
Authors: Tietz Wolfgang , Hamann Alf 
Published: March 2007

AbstractLymphocyte differentiation is connected with profound alterations in the migratory pattern of lymphocytes. Whereas naive cells predominantly recirculate through lymphoid tissues, activated lymphocytes acquire an increased preference for immigration into non‐lymphoid tissues and a reduced capacity for recirculation via high endothelial venules (HEV). A variety of data had indicated that memory‐related subpopulations of cells in man and sheep, classified by the low expression of the CD45RA isotype, also lack the capacity to recirculate via HEV. However, recent data in the rat called these results into question. We therefore analyzed the migration properties of murine CD4+ T cell subpopulations defined by several markers used to distinguish memory from naive CD4+ cells in mice, namely CD45RB, L‐selectin and CD44. Our data clearly show that the majority of putative memory cells expressing either low levels of CD45RB, low levels of L‐selectin or high levels of CD44 display a strongly reduced capacity for direct entry into lymphoid tissues, including the spleen, from the blood stream. The accumulation in peripheral lymph nodes is further reduced by treatment with anti‐L‐selectin antibody, which blocks their entry via HEV. This indicates that memory CD4+ T cells are not excluded from crossing lymph node HEV, and that the numbers of cells entering the node via this route exceed the numbers entering via the afferent lymph, at least in the absence of local inflammation. Concomitantly, a strongly enhanced localization of cells of the memory phenotype is observed in lung and liver as compared with naive cells. Trafficking to specific sites such as skin or gut mucosa is not a prominent feature of the total population of memory cells. The trafficking to lung and liver and an increased ability to bind to dendritic cells, demonstrable in in vitro adhesion assays, suggest a more sessile phenotype of most memory cells. With respect to these properties, memory cells have a surprizing similarity to fully activated lymphocytes.
Opposite role for interleukin‐4 and interferon‐γ on CD30 and lymphocyte activation gene‐3 (LAG‐3) expression by activated naive T cells
Authors: Annunziato Francesco , Manetti Roberto , Cosmi Lorenzo , Galli Grazia , Heusser Christoph H. , Romagnani Sergio , Maggi Enrico 
Published: March 2007

AbstractPolarized human type 1 and type 2 T helper cells not only produce different sets of cytokines, but they also preferentially express certain activation markers, such as lymphocyte activation gene‐3 (LAG‐3) and CD30, respectively. In this study we have examined the LAG‐3 and CD30 expression in relation to the lineage commitment of human naive CD4+ T cells, as assessed at the single‐cell level of committed T cells. Purified CD45RA+ umbilical cord blood T lymphocytes were activated with phytohemagglutinin and interleukin (IL)‐2 in the absence or presence of interleukin IL‐4 or IL‐12 and assessed for CD30 and LAG‐3 expression, as well as for intracellular cytokine synthesis. Significant numbers of CD30+ cells were only found in CD4+ and CD8+ T lymphocytes of cultures primed with IL‐4, which developed into cells able to produce IL‐4 and IL‐13 in addition to interferon (IFN)‐γ. By contrast, LAG‐3 expression was strongly up‐regulated in CD4+ and CD8+ T cells from cultures primed with IL‐12, which developed into high numbers of IFN‐γ producers. The addition of a neutralizing anti‐IFN‐γ antibody to IL‐12‐primed CD4+ T cell cultures virtually abolished the development of LAG‐3‐expressing CD4+ T cells. Taken together, these data suggest that CD30 expression is dependent on the presence of IL‐4, whereas LAG‐3 expression is dependent on the production of IFN‐γ during the lineage commitment of human naive T cells.
Double‐positive T cell receptorhigh thymocytes are resistant to peptide/major histocompatibility complex ligand‐induced negative selection
Authors: Ghendler Yoseph , Hussey Rebecca E. , Witte Torsten , Mizoguchi Emiko , Clayton Linda K. , Bhan Atul K. , Koyasu Shigeo , Chang Hsiu‐Chiang , Reinherz Ellis L. 
Published: March 2007

AbstractTo investigate negative selection events during intrathymic ontogeny, we established T cell receptor (TCR)‐transgenic mice [N15tg/RAG‐2−/− (H‐2b)] expressing a single TCR specific for vesicular stomatitis virus nuclear octapeptide N52–59 (VSV8) in the context of the major histocompatibility complex (MHC) class I molecule, Kb. Administration of VSV8 in vivo induced apoptosis in less than 4 h, deleting the majority of immature double‐positive (DP) thymocytes by 24 h. In contrast, DP TCRhigh as well as single‐positive (SP) thymocytes were refractory to this death process. Moreover, DP TCRhigh cells differentiated into SP thymocytes in vitro and in vivo, maturing into functional cytotoxic T lymphocytes upon intrathymic transfer to β RAG 2−/− recipients. Hence, negative selection processes involving MHC‐bound peptide ligands are operative only prior to the late DP thymocyte stage in this MHC class I‐restricted TCR transgene system.
Blood‐ and skin‐derived monocytes/macrophages respond to C3a but not to C3a(desArg) with a transient release of calcium via a pertussis toxin‐sensitive signal transduction pathway
Authors: Zwirner Jörg , Götze Otto , Moser Alexander , Sieber Anja , Begemann Gabriele , Kapp Alexander , Elsner Jörn , Werfel Thomas 
Published: March 2007

AbstractControversial results have been published in the past regarding the functional reactivity of monocytes (Mo) and macrophages (Mϕ) to the anaphylatoxin C3a and its degradation product C3a(desArg). In this study we performed binding and calcium mobilization experiments with recombinant human C3a (rC3a) and rC3a(desArg). Blood Mo displayed non‐inhibitable binding of FITC‐labeled rC3a (rC3aFITC) but responded to rC3a with a transient release of the intracellular calcium concentration ([Ca2+]i), whereas rC3a(desArg) was completely inactive. In contrast, binding of rC3aFITC to eosinophilic granulocytes and the mast cell line HMC‐1 which have been shown previously to express C3a binding sites could be blocked by a monoclonal anti‐C3a antibody. The rC3a‐induced [Ca2+]i release in blood Mo was pertussis toxin (PTX)‐sensitive suggesting the involvement of G‐proteins in the signal transduction pathway. Skin‐derived Mo/Mϕ reacted similarly to blood Mo as no specific binding of rC3aFITC to these cells could be demonstrated, whereas an intracellular release of calcium ions in response to the anaphylatoxin was observed. Homologous desensitization to rC3a but not heterologous desensitization to rC5a was detected in further experiments. The functional effect of C3a, but not the unspecific binding of rC3aFITC blood Mo and skin‐derived Mo/Mϕ could be blocked by the monoclonal anti‐C3a antibody. These results suggest the expression of the recently cloned G‐protein‐coupled receptor for C3a on human blood Mo and skin‐derived Mo/Mϕ. However, the total number of specific C3a binding sites on these cells is distinctly lower as compared to eosinophilic granulocytes and cells of the mast cell line HMC‐1. The small number of C3a receptors on Mo/Mϕ may be masked by a pronounced non‐inhibitable binding of rC3aFITC. This binding, however, may contribute to the recently described biological effects of C3a(desArg) on Mo.
Deviation of pancreas‐infiltrating cells to Th2 by interleukin‐12 antagonist administration inhibits autoimmune diabetes
Authors: Trembleau Sylvie , Penna Giuseppe , Gregori Silvia , Gately Maurice K. , Adorini Luciano 
Published: March 2007

AbstractNonobese diabetic (NOD) mice develop spontaneous insulin‐dependent diabetes mellitus (IDDM), and the pancreas‐infiltrating T cells invariably show a Th1 phenotype. We demonstrated here that the interleukin (IL)‐12 antagonist (p40)2 can deviate the default Th1 development of naive T cell receptor (TCR)‐transgenic CD4+ cells to the Th2 pathway in vitro. Although (p40)2 does not modify the cytokine profile of polarized Th1 cells, it prevents further recruitment of CD4+ cells into the Th1 subset. To study the involvement of Th1 and Th2 cells in the initiation and progression of IDDM, we targeted endogenous IL‐12 by administration of (p40)2 in NOD mice. (p40)2 administration to NOD mice inhibits interferon‐γ but not IL‐10 production in response to lipopolysaccharide (LPS) or to the putative autoantigen IA‐2. Serum immunoglobulin isotypes determined after (p40)2 treatment indicate an increase in Th2 and a decrease in Th1 helper activity. Administration of (p40)2 from 3 weeks of age onwards, before the onset of insulitis, results in the deviation of pancreas‐infiltrating CD4+ but not CD8+ cells to the Th2 phenotype as well as in the reduction of spontaneous and cyclophosphamide‐accelerated IDDM. After treating NOD mice with (p40)2 from 9 weeks of age, when insulitis is well established, few Th2 and a reduced percentage of Th1 cells are found in the pancreas. This is associated with a slightly decreased incidence of spontaneous IDDM, but no protection from cyclophosphamide‐accelerated IDDM. In conclusion, deviation of pancreas‐infiltrating CD4+ cells to Th2 is associated with protection from IDDM. However, targeting IL‐12 after the onset of insulitis, when the pancreas contains polarized Th1 cells, is not sufficient to induce an effective immune deviation able to significantly modify the course of disease.
Presentation of a viral peptide assembled on the carbohydrate moieties of immunoglobulin does not require processing
Authors: Brumeanu Teodor‐D. , Casares Sofia , Dehazya Philip , Bot Simona , Bona Constantin A. 
Published: March 2007

AbstractWe have previously demonstrated that an immunodominant CD4 T cell epitope, HA110‐120 of the hemagglutinin (HA) of the A/PR/8/34 influenza virus, enzymatically assembled on the carbohydrate moieties of self immunoglobulins (Ig) primed the precursors of peptide‐specific T cells and induced efficient proliferation in vivo of naive lymphocytes from transgenic mice expressing the peptide‐specific T cell receptor. Here, we show that an immuno‐galacto‐peptide construct, IgG‐gal‐HA, does not require intracellular or extracellular processing to present the peptide to the specific T cells. The presentation occurs following the binding of the IgG‐gal‐HA construct to Fcγ receptor on the surface of antigen‐presenting cells (APC), with concurrent interaction of the peptides to their neighboring major histocompatibility complex class II molecules. This mechanism of peptide presentation may harness the immune response in vivo by the engagement of APC with a low capacity of antigen processing, such as neonatal B cells. In addition, the enzymatic method of assembling various aminated compounds on the sugar moieties of Ig may offer novel perspectives on immunotargeting of antagonist peptides, cytostatic drugs, and biologically active ligands of therapeutic use.
The mannose receptor functions as a high capacity and broad specificity antigen receptor in human dendritic cells
Authors: Engering Anneke J. , Cella Marina , Fluitsma Donna , Brockhaus Manfred , Hoefsmit Elizabeth C. M. , Lanzavecchia Antonio , Pieters Jean 
Published: March 2007

AbstractDendritic cells, in contrast to B lymphocytes, must be able to efficiently internalize a diverse array of antigens for processing and loading onto major histo‐compatibility complex (MHC) class II molecules. Here we characterize the mannose receptor pathway in dendritic cells and show that mannose receptor‐mediated uptake of antigens results in a ∼ 100‐fold more efficient presentation to T cells, as compared to antigens internalized via fluid phase. Immunocytochemistry as well as subcellular fractionation revealed the localization of the mannose receptor and MHC class II molecules in distinct subcellular compartments. The mannose receptor thus functions in rapid internalization and concentration of a variety of glycosylated antigens that become available for processing and presentation. This may contribute to the unique capacity of dendritic cells to generate primary T cell responses against infectious agents.
Identification and analysis of a novel member of the ubiquitin family expressed in dendritic cells and mature B cells
Authors: Bates Elizabeth E. M. , Ravel Odile , Dieu Marie‐Caroline , Ho Stephen , Guret Christiane , Bridon Jean‐Michel , Ait‐Yahia Smina , Brière Francine , Caux Christophe , Banchereau Jacques , Lebecque Serge 
Published: March 2007

AbstractUsing a cDNA subtraction technique, a novel member of the ubiquitin family was isolated from human dendritic cells. This gene encodes a diubiquitin protein containing tandem head to tail ubiquitin‐like domains, with the conservation of key functional residues. Expression of this 777‐bp mRNA was restricted to dendritic cells and B cells, with strong expression in mature B cells. Southern blot analysis indicated that a single copy of this gene is present. In situ hybridization on tonsillar tissue showed expression in epithelial cells and isolated cells within the germinal center. With respect to an expressed‐sequence tag (EST) this cDNA could be localized to the major histocompatibility complex class I region of chromosome 6. Comparative analysis and the expression pattern of this gene suggests a function in antigen processing and presentation.
Biochemical characterization of the human diabetes‐associated HLA‐DQ8 allelic product: Similarity to the major histocompatibility complex class II I‐Ag7 protein of non‐obese diabetic mice
Authors: Reizis Boris , Altmann Daniel M. , Cohen Irun R. 
Published: March 2007

AbstractThe human HLA‐DQ8 (A1*0301/B1*0302) allelic product manifests a strong association with insulin‐dependent diabetes mellitus (IDDM). Previous biochemical studies of the major histocompatibility complex (MHC) class II I‐Ag7 protein of IDDM‐prone non‐obese diabetic mice produced controversial results. To better define the biochemical properties of IDDM‐associated MHC class II molecules, we analyzed DQ8 proteins, in comparison to other DQ allelic products, by partially denaturing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE). We now report that DQ8 proteins have a normal peptide occupancy and lifespan in cells. Similar to I‐Ag7, DQ8 proteins formed only a minor fraction of SDS‐stable complexes with peptides. Although this phenotype was not unique to DQ8, some DQ allelic products such as IDDM‐protective DQ6 proteins were SDS resistant. The DQ9 allelic product, differing from DQ8 only at position (P) β57, was SDS stable, suggesting that non‐Asp residues at β57 might decrease the SDS stability of DQ proteins. We identified a single peptide which specifically induced an SDS‐stable conformation in DQ8 as well as in I‐Ag7 molecules. The residues at anchor P1 in this peptide were found to influence the SDS stability of both molecules. Together with our previous observation of similar binding motifs of I‐Ag7 and DQ8, these results demonstrate an overall biochemical similarity of mouse and human diabetes‐associated MHC class II molecules. This similarity might contribute to a common immunological mechanism of IDDM in both species.
Anterior chamber inoculation of splenocytes without Fas/Fas‐ligand interaction primes for a delayed‐type hypersensitivity response rather than inducing anterior chamber‐associated immune deviation
Authors: Kawashima Hidetoshi , Yamagami Satoru , Tsuru Tadahiko , Gregerson Dale S. 
Published: March 2007

AbstractThe inoculation of antigens into the anterior chamber (AC) of the eye induces an antigen‐specific immune response that inhibits delayed‐type hypersensitivity (DTH). This regulatory response is known as anterior chamber‐associated immune deviation (ACAID). The ACAID response appears to be complex, as it can be elicited by a wide variety of soluble and cell‐associated antigens, including foreign, self, tumor, and alloantigens. To evaluate the contribution of Fas/Fas ligand (FasL) interaction to the induction of ACAID to alloantigens, gld and lpr mutant mice were used in conjunction with normal C3H, MRL, and BALB/c mice. ACAID was induced by inoculation of non‐irradiated splenocytes from donor mice into the AC of various recipients. After 1 week, recipients were primed intradermally with donor splenocytes. One week later DTH was measured by ear swelling. C3Hgld mutants lacking functional FasL did not develop ACAID after the AC inoculation of BALB/c splenocytes. Conversely, the AC inoculation sensitized these mutants. MRLlpr mutants, which lack Fas, developed ACAID following inoculation of BALB/c cells. AC inoculation of lpr splenocytes did not induce ACAID, but sensitized C3H recipients. Treatment of the AC inoculum with an anti‐Fas antibody blocked ACAID induction in a transient manner, as the recipients developed ACAID later. These results show that interaction of the Fas and FasL is required to induce ACAID to allogeneic cells. In the absence of Fas expression on donor splenocytes, or FasL expression by the recipient, AC inoculation primes for a DTH response rather than inducing ACAID.
Neutrophil Fcγ and complement receptors involved in binding soluble IgG immune complexes and in specific granule release induced by soluble IgG immune complexes
Authors: Voice Julia Kate , Lachmann Peter Julius 
Published: March 2007

AbstractWe examined the effect of soluble IgG immune complex (IC) characteristics on the binding of IC to human neutrophils and IC‐induced specific granule release of neutrophils via Fcγ receptors (CD16 and CD32) and complement receptors (CR1 and CR3). A set of soluble IgG IC varying in size, IgG subclass, antigen epitope density and complement (C) incorporation were formed between 5‐iodo‐4‐hydroxy‐3‐nitrophenacetyl (NIP) coupled to bovine serum albumin (BSA) and chimeric mouse‐human anti‐NIP monoclonal antibodies (mAb) of all four IgG subclasses. High and low epitope density IC of all four IgG subclasses induced specific granule release with C, but in the absence of C only IgG1 and IgG3 IC were functionally active. The Fcγ and C receptors responsible for IgG IC‐induced specific granule release and IC binding were determined using mAb specific for the ligand binding sites of CD16, CD32 and CR3, and recombinant soluble CR1. Each defined IC displayed a unique pattern of receptor preference, dependent upon subclass and antigenic epitope density. IC binding and IC‐induced specific granule release was not mediated by the same receptor, or combination of receptors. High and low epitope density IgG3 IC binding and induction of specific granule release was mediated predominantly via CD16. Other IC subclasses bound differently, i.e. IgG1 IC used CD16 and CR3; IgG2 and IgG4 predominantly used complement receptors; but all three induced specific granule release via CD32. In vivo these results may translate into differential activation of neutrophils by soluble IC dependent upon their characteristics, leading to subtle nuances in the etiology, pathology and control of the immune response in IC‐related diseases.