bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression and regulation of erythrocyte auto‐antibodies in mice following immunization with rat erythrocytes
Authors: Day Michael J. , Russell Jackie , Kitwood Alison J. , Ponsford Mary , Elson Christopher J. 
Published: March 2007

AbstractMice immunized with intact rat red blood cells (RBC) developed serum auto‐antibodies (some of which were mouse specific) to the RBC membrane components spectrin and antigens of 100 and 81 kDa as shown by Western blotting and enzyme‐linked immunosorbent assay as well as RBC surface‐bound autoantibodies detected by the Coombs' test. In order to discover whether these autoantibodies were induced and contolled in similar or different ways, mice were challenged with a variety of rat and mouse RBC preparations. In addition, the ability of recipients given spleen cells from the above donors to generate autoantibody responses to intact rat RBC was measured. It was found that all the autoantibodies were induced in mice challenged with rat RBC ghosts but none following immunization with butanol‐extracted rat RBC ghosts or intact mouse RBC. By contrast, mice injected with mouse RBC ghosts made autoantibodies to spectrin and to the 100‐kDa band. Spleen cells from mice primed with intact rat RBC, rat RBC ghosts or butanol‐extracted rat RBC ghosts curtailed Coombs' autoantibody production of recipient mice challenged with intact rat RBC. Serum from recipients of spleen cells primed with intact rat RBC or the butanol extract generally failed to react with rat or mouse spectrin or with the 81‐kDa band, although antibody was detected to the rat 100‐kDa band. Recipients of rat RBC ghost‐primed spleen cells produced antibody to rat and mouse spectrin and to rat 100‐kDa band but not to mouse 100‐kDa or rat or mouse 81‐kDa bands. Occasionally, suppression of antibody to the rat‐specific 38‐kDa band was observed in recipients of intact rat RBC‐primed spleen cells. It is therefore suggested that regulation of cross‐reactive and mouse‐specific autoantibodies as well as rat‐specific antibodies occurs in an independent, determinant‐specific manner.
One allele [G2m(n)] of the human IgG2 locus is more productive than the other
Authors: Rautonen Nina , Sarvas Heikki , Mäkelä Olli 
Published: March 2007

AbstractEarlier investigators have shown that a high serum concentration of IgG2 and a high IgG2 antibody response to several polysaccharide antigens is associated with the allotype G2m(n) of the IgG2 subclass. We now show that the total IgG2 concentrations are significantly higher in G2m(n) than in G2m(–n) homozygotes (difference of means was 1.26‐fold, p = 0.002). Furthermore, in G2m(n) heterozygotes, the G2m(n) allele contributed more than the G2m(–n) allele to specific IgG2 antibody responses and to the total IgG2.
T cell activation via the CD2 molecule is associated with protein kinase C translocation from the cytosol to the plasma membrane
Authors: Bagnasco Marcello , Nunes Jacques , Lopez Marc , Cerdan Chantal , Pierres Anne , Mawas Claude , Olive Daniel 
Published: March 2007

AbstractT cell activation via the CD2 molecule involves phospholipase C and phosphoinositide hydrolysis. Here we demonstrate that the triggering of subclones of the human T leukemia Jurkat cell line by anti‐CD2 as well as anti‐CD3 monoclonal antibodies is able to induce activation (i.e. translocation from cytosol to cell membrane) of protein kinase C (PKC), which is dependent on the formation of 1,2‐diacylglycerol from inositol 4–5‐bisphosphate. The kinetics of PKC translocation parallels the rise in intracellular calcium following both CD2 and CD3 stimulations. These results further demonstrate that CD2 and CD3 activation pathways use similar signal transduction mechanisms.
Expression and regulation of CD5 on in vitro activated human B cells
Authors: Freedman Arnold S. , Freeman Gordon , Whitman James , Segil Jeff , Daley John , Levine Herbert , Nadler Lee M. 
Published: March 2007

AbstractThe T cell‐associated antigen CD5 has been shown to play an important role in the regulation of T cell activation. Monoclonal antibodies directed against CD5 upregulate helper function, and induce interleukin 2 (IL 2) production by mature T cells as well as thymocytes. CD5 is also expressed on subsets of B cells associated with autoantibody production, and CD5+ B cells are present in increased numbers in patients with rheumatoid arthritis and systemic lupus erythematosis. More recently CD5 has been found to be present on human B lymphocytes following in vitro activation with phorbol myristate acetate. To date a similar functional role for CD5 has not to date been demonstrated for B cells. In this study we have shown that structurally similar CD5 molecules are present on activated B cells and T cells. In addition, CD5 on both stimulated B cells and T cells is phosphorylated, which may be important in the function of CD5 following activation. CD5 protein or mRNA was not detected on unstimulated splenic B cells depleted of any CD5+ cells. To investigate the control of CD5 expression, we examined a series of cytokines either alone or in combination for their effect on the induction of CD5. CD5 expression was specifically inhibited by IL 4 but not by the other cytokines tested. This inhibition was very specific as IL 4 did not inhibit the expression of other B cell activation antigens including CD25, B5, T9 and CD23 as well as the pan‐B cell antigen CD20. The addition of other cytokines did not increase or reverse the inhibition of CD5 expression by IL 4. This inhibition was demonstrated by immunofluorescence and flow cytometric analysis. Immunoprecipitation studies of 125I‐labeled activated B cells demonstrated that there was a decrease in cell surface CD5 protein, and not simply inhibition of expression of a particular epitope. Northern blot analysis demonstrated that the expression of CD5 mRNA was markedly inhibited in the presence of IL 4, whereas the induction of the protooncogene c‐myb was unaffected. This suggests that IL 4 inhibits CD5 protein expression on activated B cells by reducing the amount of CD5 mRNA transcription or increasing the degradation of CD5 mRNA. The role of the T cell‐derived lymphokine IL 4 in regulating CD5 expression may be important in the disease states characterized by increased numbers of CD5+ B cells.
Immunity to experimental infection with Leishmania major: generation of protective L3T4+ T cell clones recognizing antigen(s) associated with live parasites
Authors: Müller Ingrid , Louis Jacques A. 
Published: March 2007

AbstractExacerbation and resolution of lesions induced by Leishmania major promastigotes are, at least in part, the result of the activity of distinct parasite‐specific L3T4+ T lymphocytes. The present report describes L. major‐specific cloned L3T4+ T lymphocytes capable of transferring substantial protective immunity to normal highly susceptible BALB/c mice. The two protective T cell clones analyzed appear to recognize antigen associated only with live L. major parasites. Therefore, the pattern of antigen reactivity of these protective T cell clones is different from that of the previously described parasite‐specific L3T4+ T cells which contribute to exacerbation of disease. The results presented in this report indicate that the two opposite effects of parasite‐specific L3T4+ T cells on the disease process could be mediated by functionally similar L3T4+ T cells differing in their antigen specificity.
Interleukin 1 and tumor necrosis factor enhance transcription from the SV40 early promoter in a T cell line
Authors: Plaetinck Geert , Combe Marie Claire , Corthésy Patricia , Seckinger Philippe , Nabholz Markus 
Published: March 2007

AbstractInterleukin 1 (IL 1) and tumor necrosis factor (TNF) increase the expression of a number of T lymphocyte‐specific genes in the T cell hybrid PC60. We show here that human IL 1α and 1β, mouse IL 1α and mouse TNF‐α strongly enhance expression of reporter genes transcribed from the SV40 early promoter in this cell line. We found that IL 1 and TNF each induce up to a 30‐fold increase in the rate of transcription, resulting in a proportional increase of mRNA and protein levels. Induction with IL 1 and TNF is detectable after 1 h and reaches a plateau after about 15 h. Removal of these factors from the culture medium results in complete reversion. Induction with IL 1, but not with TNF, can be inhibited with an inhibitor of IL 1 binding. The effects of both factors are not impaired by the protein synthesis inhibitor cycloheximide, suggesting that they stimulate expression from the SV40 early promoter by activation of preexisting transcription factors.
Membrane‐bound IgM obstructs B cell development in transgenic mice
Authors: Müller Werner , Rüther Ulrich , Vieira Paulo , Hombach Joachim , Reth Michael , Rajewsky Klaus 
Published: March 2007

AbstractRearranged immunoglobulin genes encoding either the secreted (m̈s) or membrane (m̈m) form of IgM were introduced into the mouse germ line. We report here the phenotypic analysis of lymphocyte populations in these mice (Tm̈s and Tm̈m). In Tm̈s mice the transgenic m̈ chain is present in serum antibodies. The frequencies of B cells in the various B cell compartments of Tm̈S mice are normal or slightly reduced compared to littermates. In Tm̈m mice, however, B cell (but not T cell) development is severely affected. Spleens of 8‐week‐old Tm̈m mice contain about 3%–8% B cells, increasing to approximately 20% at the age of 8 months. These cells express endogenous IgM. B cells expressing only transgenic m̈m chains are not detectable. In the bone marrow B cells are almost completely depleted. A B cell population characterized by reduced levels of IgD on the cell surface is enriched in the spleen and present at almost normal levels in the peritoneum of Tm̈m mice.
Most anti‐human CD3 monoclonal antibodies are directed to the CD3 ε subunit
Authors: Transy Catherine , Moingeon Philippe E. , Marshall Bruce , Stebbins Christopher , Reinherz Ellis L. 
Published: March 2007

AbstractThe T cell receptor is a molecular complex comprized of a clonally restricted heterodimer (Ti) responsible for specific antigen recognition and a set of invariant CD3 peptides termed γ δ, ε ζ and η. The latter are believed to be involved in transmembrane signaling events given that monoclonal antibodies (mAb) directed to the native CD3 structure can trigger T cell activation. We show here that the vast majority of anti‐human CD3 mAb are directed to an epitope(s) encoded in part or in total by the ε subunit since 15 of 18 independent mAb specifically react with a murine T cell line expressing the human CD3 ε chain at its cell surface. The WT31 mAb is also reactive with this cell line showing that its target epitope, originally assigned to the Ti structure, rather maps to the CD3 ε subunit. These findings suggest that the CD3 ε subunit is the most exposed of the native CD3 structures which are immunogenic and that cross‐linking of the CD3 ε chain by mAb mediates the subsequent T cell activation via the T cell receptor complex.
Emigration of B cells from chicken bursa of Fabricius
Authors: Lassila Olli 
Published: March 2007

AbstractThe extent of emigration of cells from the bursa of Fabricius to the periphery was estimated. Per anum application of fluorescein isothiocyanate to label bursal cells in situ was used. Migrant cells can be visualized on frozen sections or cell suspensions of peripheral organs by their fluorescence. The data show that at 2–3 weeks after hatching about 5% of bursal cells leave the bursa per day. Since the bursal cells divide rapidly, this indicates that the vast majority (95%) of bursal cells die in situ. Cells that leave the bursa are surface IgM positive and go first to peripheral blood and later into B cell areas of spleen, thymus and cecal tonsils. The results are also discussed on the basis of their implication for the generation of antibody diversity in the chicken bursa.
Induction of T cell function via the gp33/27 activation inducer molecule (AIM) requires co‐expression of the CD3/TcR complex
Authors: Rincón Mercedes , Cebrián Marta , Sánchez‐Madrid Francisco , López‐Botet Miguel 
Published: March 2007

AbstractMonoclonal antibodies specific for a dimeric cell surface activation antigen (gp33/27), preliminary designated as activation inducer molecule (AIM), are capable of triggering interleukin 2 (IL 2) synthesis, IL 2 receptor expression and T cell proliferation when used in conjunction with phorbol esters. We have analyzed the functional relationship between the AIM and the CD3/TcR‐mediated activation pathways. Transient modulation of the CD3/TcR complex in the Jurkat cell line, as well as the stable loss of the CD3/TcR surface expression in variant subclones, determined an inhibition of the IL 2 production triggered by anti‐AIM monoclonal antibody (mAb). In contrast, neither the surface expression of AIM nor the ability to respond to a Ca2+ ionophore were affected. Similar results were observed in peripheral blood T lymphocytes, detecting after CD3 modulation an inhibition of both the IL 2 synthesis and the proliferative response to anti‐AIM mAb. Altogether our data indicate that the activation pathway triggered by anti‐AIM mAb is functionally linked to the expression of the CD3/TcR complex in mature T cells.
CD8+CD11b+ peripheral blood T lymphocytes contain lymphokine‐activated killer cell precursors
Authors: Dianzani Umberto , Zarcone Daniela , Pistoia Vito , Grossi Carlo E. , Pileri Alessandro , Massaia Massimo , Ferrarini Manlio 
Published: March 2007

AbstractCD3+CD8+ cells, purified from peripheral blood T cells by depletion of CD4+ lymphocytes, were tested for their cytotoxic activity against K‐562 or HL‐60 cells. Freshly prepared cells had no cytotoxic function, but upon exposure to recombinant interleukin 2 (rIL 2) in vitro they acquired a lymphokine‐activated killer (LAK) activity. Fractionation of CD3+CD8+ cells into CD11b+ and CD11b− cells demonstrated that all the cells with the potential of developing LAK cell functions were within the CD8+CD11b+ subset. These cells lacked natural killer cell markers such as CD16 or NKH1, but a proportion of them stained for Leu‐7. Furthermore, they expressed the α/β chains, but not the γ/δ chains, of the T cell receptor, as could be determined by staining with the appropriate monoclonal antibodies. CD8+CD11b+ cells had a large granular lymphocyte morphology, as shown by both cytochemical and electron microscopy analyses. They proliferated in response to IL 2 in vitro and developed cytotoxic functions against a number of natural killer resistant targets. Their response to phytohemagglutinin or pokeweed mitogen was very weak or absent. By contrast, CD8+CD11b− cells failed to generate LAK cells in response to rIL 2, did not show a large granular lymphocyte morphology, but responded vigorously to phytohemagglutinin or pokeweed mitogen.Purified CD8+CD11b+ cells were cloned by limiting dilution in the presence of rIL 2. The observed cloning efficiency of 19 ± 0.3% indicates that a fraction of the cells only could respond to IL 2. Furthermore, only 50% of the clones obtained had a LAK cell function. These data show that CD8+CD11b+ cells represent a heterogeneous cell population. Nevertheless this cell subset probably represents the major source of LAK cell progenitors within the circulating T cells.
Monoclonal antibody 5.5 reacts with p8,14, a myeloid molecule associated with some vascular endothelium
Authors: Hogg Nancy , Allen Catherine , Edgeworth Jonathan 
Published: March 2007

AbstractThe movement of mononuclear phagocytes and neutrophils from the circulation into tissues is a process which is not completely understood. Monoclonal antibody 5.5 is specific for an 8/14‐kDa molecule known variously as the CF antigen, L1 molecule or MRP8 and 14. We show that this molecule, which will be named p8, 14 in this study, is expressed in all circulating monocytes and neutrophils as an intracellular product (as well as some types of epithelium). Tissue staining patterns suggest that when monocytes and neutrophils adhere to vascular endothelium, they release this molecule onto the associated endothelium. This process occurs with single monocytes and when monocytes form part of an inflammatory infiltrate. Monoclonal antibody 5.5 does not react with cultured endothelial cells even when stimulated with phorbol ester, tumor necrosis factor, interferon‐γ or interleukin 1α providing further evidence that myeloid cells are the source of the p8, 14 in this interactive process. Monocytes which have moved further into such tissues and tissue macrophages in general are monoclonal antibody 5.5 negative, suggesting that the ability to synthesize this molecule may be lost when monocytes leave the circulation and enter tissues. These results indicate that p8,14 plays a role in the interaction between myeloid cells and the vascular endothelium to which they adhere prior to leaving the circulation.
Proliferation of lymphocyte subsets in the adult rat: a comparison of different lymphoid organs
Authors: Westermann JÜRgen , Ronneberg Sabine , Fritz Franz Joachim , Pabst Reinhard 
Published: March 2007

AbstractAdult, male Lewis rats received a single injection of 5‐bromo‐2′‐deoxyuridine (BrdUrd) i.v. to label proliferating cells in the S phase of the cell cycle. After 1 and 24 h the thymus, bone marrow, blood, spleen, peripheral, cervical and mesenteric lymph nodes as well as Peyer's patches were removed. In cell suspensions surface staining was performed for B, T, T helper (Th) and cytotoxic/suppressor (Tc/s) T lymphocytes by identifying χ light chain, CD5+, CD4+ and CD8+ cells, respectively. On the same slide the DNA label BrdUrd was demonstrated by a monoclonal antibody.B, T, Th and Tc/s lymphocytes proliferate locally both in central lymphoid organs such as the thymus and the bone marow, and in peripheral lymphoid organs such as the spleen, lymph nodes and Peyer's patches. Within an organ the amount of proliferation among the lymphocyte subsets is similar, differing not more than threefold. Although concerning only a small fraction of cells within the organ, an unexpected finding is the high percentage of BrdUrd‐labeled cells among B lymphocytes in the thymus (3%) and among T lymphocytes in the bone marrow (3%). One day after injection of BrdUrd the thymus contains 25% BrdUrd+ T lymphocytes, while the other organs investigated do not show more than about 2% BrdUrd+ B and T lymphocytes. Many of the newly formed lymphocyte subsets leave their organ of birth within 24 h. Thus the amount of proliferation in the lymphocyte subsets investigated is very similar and the differences between central (thymus and bone marrow) and peripheral lymphoid organs are much smaller than expected.
Characterization of C3a receptor‐proteins on guinea pig platelets and human polymorphonuclear leukocytes
Authors: Gerardy‐Schahn Rita , Ambrosius Dorothee , Saunders Derek , Casaretto Monica , Mittler Christa , Karwarth Gabriele , Görgen Susanne , Bitter‐Suermann Dieter 
Published: March 2007

AbstractThe expression of specific membrane receptors for C3a was determined on guinea pig C3a‐sensitive (gp R+) platelets and human polymorphonuclear leukocytes (hu PMNL). Binding studies with 125I‐labeled C3a from gp or hu sources and Scatchard analysis applied to the binding data revealed the existence of two receptor classes on gp R+ platelets; a high‐affinity class with about 200 binding sites/cell and Kd = 1.7 x 10−9 M, and a relatively low‐affinity class with Kd = 10−8 M and about 500 sites/cell. Hu PMNL express a homogeneous receptor class with Kd = 3 x 10−8 M and 40000 sites/cell. Molecular characterization of the C3a receptor on gp R+ platelets was achieved by (a) cross‐linking photoaffinity‐labeled receptors to bound 125I‐labeled C3a; (b) photoaffinity labeling receptors with a 13‐amino acid residue C3a analogue 125I‐Nap‐Ahx‐13; and (c) use of chemical cross‐linkers like disuccinimidylsuberate to cross‐link receptors with 125I‐C3a. All three techniques gave rise to very similar labeling patterns. With the photoaffinity labeling methods, a diffuse band pattern was observed with an apparent molecular mass of 95–123 kDa with 125I‐C3a as label, and 85–105 kDa with 125I‐Nap‐Ahx‐13 as label. Chemical cross‐linking of 125I‐C3a revealed three distinct bands with molecular masses of approximately 123, 108 and 95 kDa. Subtracting the contribution of the cross‐linked ligands, the C3a receptor on gp R+ platelets appears to be a protein complex, consisting of one to three components with estimated molecular masses between 83–114 kDa.
Immunoglobulin VH gene expression in Ly‐1+ and conventional B lymphocytes
Authors: Andrade Luiz , Freitas António A. , Huetz François , Poncet Pascal , Coutinho António 
Published: March 2007

AbstractLymphocyte populations in which Ly‐1 B cells are differentially represented were studied for the expression of ten VH gene families, either by an RNA colony blot assay or by in situ hybridization of single cells, in BALB/c and C57BL/6 mice. The comparisons of cells from lymph nodes, Peyer's patches and adult spleen (poor in Ly‐1 B cells) with cells from peritoneal cavity and neonatal spleen (rich in Ly‐1 B cells) were confirmed by the analysis of adult peritoneal Ly‐1− and Ly‐1+ B cells sorted on the fluorescence‐activated cell sorter. The results indicate that the peritoneal Ly‐1+ B subset uses the whole spectrum of known VH gene families, and shows a preferential utilization of CP12 VH genes, most likely as a result of a selective process during life.
Histone H1° mapping using monoclonal antibodies
Authors: Dousson Sandrine , Gorka Claude , Gilly Claudine , Lawrence Jean‐Jacques 
Published: March 2007

AbstractMonoclonal antibodies (mAb) to ox liver histone H1° were produced and characterized. Two sets of mice were immunized either with pure H1° or with an H1°‐yeast tRNA complex. Eleven hybridomas of various clonal origin were selected. Typing of the antibodies indicated that all but three IgM belonged to the IgG1 class and contained χ light chains. Immunoblotting experiments using peptides derived from H1° or H5 treated by various proteolytic agents (trypsin, N‐bromosuccinimide, cyanogen bromide, acetic acid), revealed that nine of the mAb reacted with the globular part of H1°. More advanced characterization of the antigenic determinants allowed us to determine distinct regions within this globular part which are involved in the antigenic recognition. The peptopes could be subdivided into two groups. Three mAb bound to residues 24–27 and were specific for H1°. Six mAb bound to residues 27–30 and were specific for H1° except one of them which strongly cross‐reacted with H5 and GH5. Two mAb reacted with the entire histone H1° but failed to react with any of the peptides, suggesting that the corresponding epitope is a conformational antigenic determinant. In order to confirm the localization of the two distinct regions which are involved in the antigenic recognition, a synthetic decapeptide corresponding to the beginning of human H1° globular part (from residue 19 to residue 28) was synthesized. Inhibition experiments of the reaction between H1° and the various IgG1 mAb by increasing amounts of peptide‐bovine serum albumin conjugates were then performed.