bluuebunny/crossref_metadata_2025_split huggingface dataset:
The monoclonal antibody ER‐BMDM1 recognizes a macrophage and dendritic cell differentiation antigen with aminopeptidase activity
Authors: Leenen Pieter J. M. , Melis Marleen , Kraal Georg , Hoogeveen Andre T. , Ewijk Willem Van 
Published: March 2007

AbstractHere we describe the reactivity of monoclonal antibody (mAb) ER‐BMDM1, directed against a 160‐kDa cell membrane‐associated antigen (Ag) with aminopeptidase activity. The aminopeptidase recognized by ER‐BMDM1 is present on various mouse macrophage (MΦ) and dendritic cell (DC) subpopulations as well as on microvillous epithelia. Analysis of ER‐BMDM1 Ag expression in in vitro models of MΦ maturation revealed that the Ag is expressed at increasing levels upon maturation of MΦ. In vivo, high level expression of the ER‐BMDM1 Ag occurs after thmonocytic stage of maturation, since bone marrow cells and peripheral blood monocytes are essentially ER‐BMDM1 negative. Analysis of isolated‐resident and elicited MΦ populations showed that ER‐BMDM1 recognizes a specific subpopulation of mature MΦ: only some resident peritoneal and alveolar MΦ are ER‐BMDM1 positive, whereas virtually all thioglycollate‐elicited peritoneal exudate MΦ bind the mAb. In lymphoid organs, a subpopulation of MΦ is recognized as well as interdigitating cells (IDC) located in T cell areas. Phenotypic analysis of isolated DC‐ the in vitro equivalents of IDC ‐ from spleen and lymph nodes confirmed that the majority of this important antigen‐presenting cell population expresses the ER‐BMDM1 aminopeptidase. The molecular characteristics of the ER‐BMDM1 Ag suggest that it may represent the mouse homolog of human CD13.
Complement regulatory proteins at the feto‐maternal interface during human placental development: distribution of CD59 by comparison with membrane cofactor protein(CD46) and decay accelerating factor (CD55)
Authors: Holmes Christopher H. , Simpson Karen L. , Okada Hidechika , Okada Noriko , Wainwright Shane D. , Purcell Damian F. J. , Houlihan James M. 
Published: March 2007

AbstractThe complement (C) regulatory proteins decay‐accelerating factor (DAF, CD55)and membrane cofactor protein (MCP, CD46), which control C3 convertases, together with CD59, an inhibitor of the membrane attack complex (MAC), were found to be present in the developing human placenta from at least 6 weeks of gestation until term. Immunostaining revealed differences in the distribution of these proteins on the fetally derived trophoblast epithelium, especially in early placentae which contain trophoblast populations of diverse proliferative potential and differentiation status. Expression of all three proteins occurred on the terminally differentiated syncytiotrophoblast epithelium covering chorionic villi and which is in direct contact with maternal blood. CD59 was also expressed on the underlying villous cytotrophoblast cells and on their extra‐villous derivatives. These two populations showeddifferential expression of the C3 convertase regulators. Villous cytotrophoblast cells expressed MCP but were largely devoid of DAF. Proliferation of this population to generate extra‐villous cytotrophoblast cellcolumns was associated with both an increase in DAF expression and a decrease in MCP expression. Throughout placental development, expression of DAF appeared to be lower than that of MCP and CD59 as assessed by solid‐phase binding assays on isolated trophoblast membranes. Early placentae were also found to contain both DAF+ and DAF− chorionic villi. Conversely, expression of CD59 appeared comparatively high and transcripts for CD59 were found to be much more abundant than those for DAF in purified trophoblast cells. C regulatory proteins appear to play an important role throughout gestation in protectingthe fetally derived human conceptus from maternal C. The differential expression patterns of the proteins on trophoblast may reflect differences in requirement for specific functional activities at different locations within the placenta.
Preferred size of peptides that bind to H‐2 Kb is sequence dependent
Authors: Deres Karl , Schumacher Ton N. M. , Wiesmüller Karl‐Heinz , Stevanovic Stefan , Greiner Georg , Jung Günther , Ploegh Hidde L. 
Published: March 2007

AbstractThe identification of naturally processed viral peptides reveals that major histocompatibility complex (MHC) class I epitopes are composed of nine or eight amino acid residues. Peptides eluted from H‐2 Kb MHC class I molecules have been suggested, as a class, to be eight amino acid residues long. To assay for peptide‐class I interactions, a stabilization assay described for surface labeled “empty” class I molecules was employed, but on biosynthetically labeled class I molecules. The Sendai virus nucleoprotein‐derived octapeptide APGNYPAL does not bind and stabilize Kb molecules, whereas other octameric Kb−restricted peptides and the nonameric peptide FAPGNYPAL interact stably. We attribute the failure of Sendai octamer binding to the presence of proline in position two: replacement of proline renders the resulting octamers as efficient as FAPGNYPAL for binding and stabilization of H‐2 Kb. Substitution of glycine in position three of APGNYPAL slighty improves its Kb stabilizing capacity. Iodination of the tyrosine residue significantly alters the binding properties of the nonamer peptide. We conclude that the length of epitopes as selected by the class I Kb molecule is influenced by their sequence and suggest that proper positioning of the NH2 terminus of peptides is essential for class I stabilizing properties. The ability to stabilize newly synthesized “empty” class I molecules with peptide argues against an involvement of β2 microglobulin exchange in the experiments described here.
The monoclonal antibody MEL‐14 can block lymphocyte migration into a site ofchronic inflammation
Authors: Dawson Janet , Sedgwick Anthony D. , Edwards Jonathan C. W. , Lees Peter 
Published: March 2007

AbstractThe effect of MEL‐14, a monoclonal antibody which binds to the lymphocyte homing receptor (MEL‐14 Ag) on lymphocytes for peripheral lymph node (PLN) high endothelial venules (HEV), was investigated on lymphocyte migration into a delayed‐type hypersensitivity (DTH)‐like lesion produced by sensitization and challenge to Bordetella pertussis vaccine (BPV). Pretreatment of lymphocytes with saturating concentrations of MEL‐14 caused a highly significant inhibition of lymphocyte migration into the chronically inflamed site and PLN. This finding suggests that lymphocyte migration into the BPV‐induced site of chronic inflammation may be regulated by the same mechanism as lymphocyte migration into the PLN. It further indicates that the ligand for the MEL‐14 Ag adhesion molecule, recognized by lymphocyte which home to the PLN, may also be expressed on HEV‐like vessels at sites of BPV‐induced chronic inflammation.
Sensitivity of T cells to anti‐CD3‐stimulated suicide is independent of functional phenotype
Authors: Russell John H. , Rush Brian J. , Abrams Scott I. , Wang Ruduan 
Published: March 2007

AbstractWe have examined mixed populations and cloned murine CD4+ T cell lines for their sensitivity to anti‐CD3‐stimulated suicide. The sensitivity of CD4+ clones to anti‐CD3‐stimulated suicide is independentof their interleukin‐2/interleukin‐4 or interferon‐γ secretion profile or their lytic efficiency in anti‐CD3 redirected lytic assays.
Secretion of granulocyte‐macrophage colony‐stimulating factor by human blood monocytes is stimulated by engagement of Fcγ receptors type I by solid‐phase immunoglobulins requiring high‐affinity Fc‐Fcγ receptor type I interactions
Authors: Herrmann Friedhelm , de Vos Sven , Brach Marion , Riedel Detlef , Lindemann Albrecht , Mertelsmann Roland 
Published: March 2007

AbstractDespite reports on the secretion of granulocyte — macrophage — colony‐stimulating factor (GM‐CSF) by murine peritoneal macrophages in response to inflammatory stimuli, the ability of human monocytes to generate this growth factor has remained doubtful. Neither endotoxin, phorbol compounds, nor inflammatory cytokines have been shown to elicit GM‐CSF by these cells. Our present studies indicate that exposure of monocytes to solid‐phase murine IgG2a, but not to murine IgG1 and thus cross‐linkage of the 72‐kDa FcγRI results in transcription of the GM‐CSF gene, accumulation of stable GM‐CSF mRNA and finally in release of biologically active GM‐CSF protein. Cross‐linking of FcγRI by a murine anti‐FcγRI monoclonal antibody and goat anti‐mouse antibody failed, however, to stimulate GM‐CSF release. This suggests that high affinity Fc‐FcγRI interactions are required for induction of expression of GM‐CSF by monocytes.
Anergy induced by thymic medullary epithelium
Authors: Schönrich Günther , Momburg Frank , Hämmerling Günter J. , Arnold Bernd 
Published: March 2007

AbstractThymocytes can be rendered tolerant by non‐deletional mechanisms upon interaction with major histocompatibility complex (MHC) antigens on thymic epithelium. Whether the epithelial cells in the cortex or medulla could mediate this effect was not clear so far. To address this question, a transgenic mouse was generated in which the bovine keratin IV promoter was used to control expression of the alloantigen Kb. In the periphery the Kb transgene was expressed on a subset of keratinocytes. In the thymus expression was restricted to a subpopulation of medullary epithelial cells. No expression was found in the cortex. Such a tissue distribution has been reported for the keratin IV molecule demonstrating the faithfulness of the promoter used here.To follow the fate of the Kb‐reactive thymocytes, this mouse was mated with another transgenic mouse expressing an anti‐Kb T cell receptor (TcR). In the double‐transgenic mice the CD8+CD4− thymocytes were not deleted but they were found to be anergic as assayed by their failure to be activated in vitro by either Kb‐positive spleen cells or by cross‐linked anti‐TcR antibodies. These observations establish that expression of an MHC class I antigen in the thymic medullary epithelium is sufficient to induce anergy in the mature CD8+CD4− thymocyte population.
Human monoclonal and polyclonal anti‐human immunodeficiency virus‐1 antibodies share a common clonotypic specificity
Authors: Wang Haitao , Müller Sybille , Köhler Heinz , Zolla‐Pazner Susan 
Published: March 2007

AbstractHuman monoclonal and purified polyclonal anti‐human immunodeficiency virus(HIV)‐1 antibodies were tested for binding to a murine monoclonal anti‐idiotypic antibody (1F7, IgM, χ). Four human monoclonal anti‐p24 and three human monoclonal anti‐gp120 antibodies express the 1F7 clonotype, while one human monoclonal anti‐gp41 antibody does not bind to 1F7. Affinity‐purified anti‐p24 and anti‐gp120 antibodies from HIV‐1‐infected individuals also react with 1F7. Western blot analysis and enzyme‐linked immunosorbent assay confirmed that 1F7 reacts with human antibodies of different HIV‐1 antigen specificities. A survey of sera from 329 HIV‐1‐infected individuals showed binding to 1F7 in 239 sera (72.6%) while 1F7 was not reacting with 109 HIV‐1‐negative sera. These results show that 1F7 idiotype is an HIV‐1 infection‐associated clonotypic marker shared by anti‐HIV‐1 antibodies with different epitope specificites.
CD4+ suppressor cells of autoimmune encephalomyelitis respond to T cell receptor‐associated determinants on effector cells by interleukin‐4 secretion
Authors: Karpus William J. , Gould Karen E. , Swanborg Robert H. 
Published: March 2007

AbstractWe have previously demonstrated that CD4+ suppressor T cells (Ts) inhibit the secretion of interferon (IFN)‐γ, but not interleukin (IL)‐2, by effector cells of experimental autoimmune encephalomyelitis (EAE). Moreover, CD4+ Ts appear to regulate IFN‐γ by secretion of transforming growth factor‐β. We now show that CD4+ Ts produce a lymphokine with IL‐4 activity in response to a determinant associated with EAE effector cells. CD4+ Ts do not proliferate or secrete IFN‐γ, IL‐2, or IL‐4 in response to myelin basic protein, nor do CD4+ Ts proliferate or secrete IL‐2 when co‐cultured with irradiated EAE effector cells. Rather, CD4+ Ts secrete IL‐4 when co‐cultured with either irradiated effector spleen cells or irradiated encephalitogenic line cells. CD4+ Ts do not secrete IL‐4 in response to OVA‐primed spleen cells, suggesting that the suppressor cells recognize a determinant specific to encephalitogenic T cells. Furthermore, CD4+ Ts secrete IL‐4 when cultured with synthetic T cell receptor (TcR) Vβ8, but not TcR Vβ14 peptide, in the presence of antigen‐presenting cells. This response is major histocompatibility complex class II restricted as demonstrated by inhibition of the response with anti‐class II monoclonal antibody. These results suggest that CD4+ Ts recognize a determinant associated with TcR on the surface of EAE effector cells and respond by secreting IL‐4, in a manner analogous to the Th2 lymphocyte subtype.
An anti‐B cell autoantibody from Wiskott‐Aldrich syndrome which recognizes i blood group specificity on normal human B cells
Authors: Grillot‐Courvalin Catherine , Brouet Jean‐Claude , Labaume Sylvaine , Piller Friedrich , Rassenti Laura Z. , Silverman Greg J. , Kipps Thomas J. , Silberstein Leslie 
Published: March 2007

AbstractWe previously identified IgM autoantibodies in the sera of patients with Wiskott‐Aldrich syndrome (WAS) that react with a subset of normal human B lymphocytes and induce B cell differentiation in vitro. From splenocytes of a patient with WAS we generated heterohybridomas (HY18 and HY21) and a lymphoblastoid cell line (LWA10) that produce human IgM λ or IgM χ anti‐B lymphocyte autoantibodies, respectively. Immunohistochemical and multiparameter flow cytometric analyses demonstrate that these autoantibodies are specific for lymphocytes of the B lineage and preferentially stain B cells that reside in the mantle zone of secondary follicles and that constitutively co‐express the CD5 surface antigen and most major autoantibody‐associated cross‐reactive idiotypes; in addition, these antibodies stain most pre‐B cells in adult bone marrow. Molecular studies show that these anti‐B lymphocyte autoantibodies are encoded by a highly conserved VH4 gene, designated VH4.21. The gene encodes a number of autoantibodies, especially anti‐i and anti‐I IgM cold agglutinins. Hemagglutination and surface labeling studies reveal that HY18 and LWA10 recognize the “i” carbohydrate antigenic determinant(s) which is classically found on human cord red blood cells and, as shown now by this study, on a subpopulation of human B cells which expresses it early in B cell development. These studies raise the possibility that the gene product encoded by this highly conserved germ‐line VH4 gene may play a physiological role in B cell development and/or differentiation.
Specificity, T cell receptor diversity and activation requirements of CD4+ and CD8+ clones derived from human melanoma‐infiltrating lymphocytes
Authors: Pandolfino Marie‐Christine , Viret Christophe , Gervois Nadine , Guilloux Yannick , Davodeau François , Diez Elisabeth , Jotereau Francine 
Published: March 2007

AbstractTo try to understand the functional significance of human melanoma‐infiltrating lymphocytes (TIL), a clonal analysis of the specificity, T cell receptor (TcR) diversity and activation requirements of these lymphocytes isolated from four different tumors was carried out. Supporting the presence of in vivo primed tumor‐specific T lymphocytes in these four tumors, a high frequency of the CD8+ and CD4+ clones, obtained from the TIL cultured for a few days with recombinant interleukin (rIL)‐2 and autologous tumor cells, exhibited a restricted lysis or proliferation in response to the autologous tumor cell line. In contrast, no tumor‐specific clone was obtained from freshly extracted TIL, suggesting that the frequency of tumor‐specific effectors remained low in these tumors. Only the CD8+ clones lysed the autologous tumor cells and their activity was major histocompatibility complex MHC class I restricted. Significant expansion of CD4+ and CD8+ tumor‐specific clones required regular restimulation by autologous melanoma cells but also the addition of exogenous IL‐2 and of Epstein‐Barr virus‐transformed B feeder cells. Five different tumor‐specific clones, three CD8+ and two CD4+ clones were identified in a single tumor on the basis of their TcR gene configuration. Together, these data suggest that a spontaneous and diverse immune response, mediated by tumor‐specific CD4+ as well as CD8+ T lymphocytes, arises in most MHC‐bearing human melanomas but that antigen‐MHC complex presentation by tumor cells does not, at least in vitro, allow a significant proliferation of these lymphocytes.
Cell adhesion molecules of the immunoglobulin supergene family as tissue‐specific autoantigens: induction of experimental allergic neuritis (EAN) by PO protein‐specific T cell lines
Authors: Linington Christopher , Kosin Sabine , Mongan Laura , Lassmann Hans , Ozawa Kyoko 
Published: March 2007

AbstractThe PO glycoprotein is a homophilic cell adhesion molecule of the immunoglobulin supergene family which is responsible for maintaining the structure of compact internodal myelin in the peripheral nervous system (PNS). Utilizing a panel of synthetic PO peptides two distinct T cell epitopes have been identified that can induce T cell‐mediated experimental autoimmune neuritis (EAN) in the Lewis rat. One T cell epitope (amino acid residues 56–71), is located within the extracellular, immunoglobulin‐like domain of PO, while the other disease‐inducing T cell epitope (residues 180–199) is located within the proteins cytoplasmic carboxyterminal domain. The adoptive transfer of 106 CD4+ T line cells specific for either of these peptide antigens induced EAN in syngeneic recipients. However, while the pathogenic response induced by both peptide‐specific T cell lines was identical, their epitopes differ markedly in their immunologic properties in vivo. In particular while the response to peptide p180–199 was immunodominant in animals immunized with either purified PO protein or the native membrane‐bound PO protein in autologous rat peripheral nerve myelin, no response to peptide p56–71 was detected, indicating that this epitope is cryptic. This study provides the first experimental evidence that the immunoglobulin‐like domains of members of the immunoglobulin supergene family can function as target autoantigens in T cell‐mediated autoimmune disease.
CD45 isoform expression during T cell development in the thymus
Authors: Fujii Yoshitaka , Okumura Meinoshin , Inada Keiji , Nakahara Kazuya , Matsuda Hikaru 
Published: March 2007

AbstractVarious isoforms of leukocyte common antigen, or CD45, are expressed differentially on T cells at different stages of development and activation. We report studies on CD45 isoform expression on various subsets of human T cells using two‐ and three‐color flow cytometry and cell depletion. Bone marrow cells that were depleted of CD3+ and HLA‐DR+ cells were CD45RA−RO−. The earliest CD3−CD4−CD8−CD19− thymocytes were CD45RO− with 20%–30% CD45RA+ cells. The most prominent population of CD4+CD8+ double‐positive thymocytes were CD45RA−RO+. Even the CD4+CD8+ blasts were >90% CD45RO+. About 80% of single‐positive thymocytes (CD4+CD8− or CD4−CD8+) were also CD45RO+. Only 4.3% of CD4+ and 18% of CD8+ single‐positive thymocytes were CD45RA+. In constrast, cord blood T cells which represent the stage that immediately follows single‐positive thymocytes, contained 90% CD45RA+ cells. Thus, in terms of CD45 isoform expression, single‐positive thymocytes are more like double‐positive cells than cord blood T cells. These results suggest the following sequence of CD45 isoform switching during T cell development: CD45RA−RO− or RA+RO− (double‐negative thymocytes) → RA−RO+ (double‐positive and most single‐positive thymocytes) → RA+RO− (cord blood T cells), the last switch from CD45RO to CD45RA occurring as a final step of maturation in the thymus.
Induction of homotypic T cell adhesion by triggering of leukocyte function‐associated antigen‐1α (CD11a): differential effects on resting and activated T cells
Authors: Koopman Gerrit , Pals Steven T. , de Graaff Michael , Huysmans Anita C. L. M. , Meijer Chris J. L. M. 
Published: March 2007

AbstractThe leukocyte integrin LFA‐1 (CD11a/CD18) plays a key role in many adhesive interactions involving cells of the immune system. Recently, it has been shown that LFA‐1 is not only involved in cell adhesion, but that stimulation of LFA‐1 can also contribute to cell activation. We now demonstrate that triggering of LFA‐1 on T lymphocytes by monoclonal antibodies (mAb) against the LFA‐1α chain, but not against the LFA‐1β chain, promotes cell adhesion. Induction of homotypic adhesion was only observed in T cells that had been pre‐activated with anti‐CD3 and not in resting peripheral blood T lymphocytes. The induced homotypic adhesion is mediated by LFA‐itself, because it was inhibited by anti‐LFA‐1β mAb. This notion is supported by the temperature and divalent cation dependence which is characteristic of LFA‐1‐mediated adhesion. mAb against ICAM‐1 (CD54) did not block LFA‐1α‐induced adhesion. The sensitivity of LFA‐1α‐induced adhesion to H7, which prevents the activation of protein kinase C and protein kinase A, and to cytochalasin B, which inhibits microfilament formation, suggests that the activation of the LFA‐1 pathway through the LFA‐1α chain involves cell activation and requires an intact cytoskeleton.
Eosinophil as antigen‐presenting cell: activation of T cell clones and T cell hybridoma by eosinophils after antigen processing
Authors: Pozo Victoria Del , de Andrés Belen , Martín Elena , Cárdaba Blanca , Fernández Julio Cesar , Gallardo Soledad , Tramón Paloma , Palomino Pilar , Lahoz Carlos , Leyva‐Cobian Francisco 
Published: March 2007

AbstractWe have studied the role of murine eosinophils as antigen‐presenting cells (APC). Eosinophils have several characteristics that support the hypothesis of its function as potential APC: they have phagocytic capacity, express adhesion molecules and major histocompatibility complex (MHC) class II antigens and can produce and release interleukin‐1 (IL‐1).We have obtained several T cell clones specific for Mesocestoides corti antigens and used T cell hybridoma specific for ovalbumin (OVA) to test this hypothesis. Granulocyte‐macrophage colony‐stimulating factor‐activated pure eosinophils (99.9%), express class II antigens and are able to present M. corti antigens to specific T cell clones or OVA to T cell hybridoma 3DO 11.10, inducing the proliferation of T cell clones and IL‐2 release by the T cell hybridoma. Proliferation of T cells clones is dependent on the number of eosinophils used as APC. We have compared the efficiency of the same number of macrophages and eosinophils as APC, and have found that macrophages are more efficient than eosinophils. Lysosomotropic agents, such as chloroquine and ammonium chloride, that inhibit antigen processing, impaired eosinophil presentation. This presentation is restricted by MHC class II and inhibited by anti‐I‐Ad monoclonal antibody. The present study provides clear evidence of APC function for eosinophils. Our investigation points to a new role for eosinophils in the immune response.