bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age‐dependent changes in tolerizability with rabbit gamma‐globulin in the Biozzi high and low‐responder lines of mice
Authors: Papers Short , Nakano Katsuji , Cinader Bernhard , Sabiston Brian H. 
Published: February 2007

AbstractThe antibody response to rabbit gamma‐globulin (RGG) of high‐responder, but not of low‐responder Biozzi mice decreased with age. Injection with aggregate‐freed RGG reduced the response of high‐responder but not of low‐responder mice to subsequent injections with aggregated RGG. This reduction in the antibody response, formed by high‐responder mice, decreased with increasing age; aggregate‐freed RGG appeared to sensitize 6‐month‐old low‐responder mice to a subsequent injection with aggregated RGG. When animals, not pretreated with aggregate‐freed RGG, were immunized with RGG and lipopolysaccharide (LPS), the immune response was greatly enhanced. The response of both pretreated low and high responders was substantially smaller than that of corresponding animals which were not given aggregate‐freed RGG, prior to immunization. LPS revealed an inhibitory effect on low‐responder mice of aggregate‐freed RGG, which was not detected upon immunization with heat‐aggregated RGG alone. The involvement of nonspecific suppressor cells and of B cell tolerance in low‐responder mice is discussed.
Failure of allogeneic thymocytes to survive in nude mice
Authors: Piguet Pierre‐François , Vassalli Pierre 
Published: February 2007

AbstractAthymic nude mice or thymectomized mice, irradiated and reconstituted with T‐ depleted bone marrow cells (“B mice”), were injected with allogeneic or syngeneic thymocytes bearing caryotypically distinct chromosomes. The fate of the thymocytes was investigated after various periods of time using two methods: (a) frequency of the cells bearing the Thy‐1 antigen as detected by immunofluorescence with a heteroantiserum among the recipient spleen cells, (b) presence of chromosomally detectable donor cells in phytohemagglutinin‐stimulated spleen cell cultures. These two methods indicate that allogeneic thymocytes disappear after about 7 days, semiallogeneic thymocytes after about 20 days, while syngeneic thymocytes, even when injected in 50 times lower number (106 cells), are detectable for months, thanks to the sensitivity of the caryotypic method. Allogeneic thymocytes induce the production of high titers of alloantibodies, which were shown to react specifically against their own H‐2, a phenomenon interpreted as a “suicidal” allogeneic collaboration. These experiments demonstrate that the failure of allogeneic thymocytes, in contrast to syngeneic thymocytes, to achieve long‐term restoration of the immune responsiveness of T‐depleted mice is due to a rejection of the foreign thymocytes, and not to a failure of T and B cells to collaborate across the histocompatibility barrier.
Stimulation of regulatory T cell circuits by immunoglobulin‐dependent structures on activated B cells
Authors: L'age‐Stehr Johanna , Teichmann Hans , Gershon Richard K. , Cantor Harvey 
Published: February 2007

AbstractAn immunoregulatory circuit is described in which B cell blasts activate syngeneic Ly‐1+2−3− T cells to (a) start a reaction which is indistinguishable from a graft‐vs.‐ host reaction (syngeneic GvH) and (b) induce suppressor cell activity which abrogates the syngeneic GvH. Since capping the surface immunoglobulin (Ig) on B cell blasts blocks their ability to activate this circuit, it is likely that the relevant cell surface structure “seen” on the B cell by the Ly‐1 T cell is either Ig itself or another molecule in association with Ig.
Prolonged exposure to antigen induces specific unresponsiveness of mixed leukocyte culture‐activated cells
Authors: Sagman Julius Gordon Uri , Rode Harold 
Published: February 2007

AbstractOne‐way mixed leukocyte cultures, supplemented by the daily addition of small numbers of fresh stimulating cells between days 5 and 15 of incubation, failed to give a secondary proliferative or cell‐mediated lyrnpholytic response upon challenge with activating concentrations of the same stimulating cells. However, these cultures could be fully activated by blastogenic factor (BF). The unresponsiveness induced was immunologically specific: when reponding cells were primed simultaneously with stimulating cells from two donors and one stimulator was added daily, the cultures were unresponsive to challenge with cells of the stimulator which were added daily, but good secondary responses were elicited both by cells of the other stimulator used in priming and by BF. The induced unresponsiveness may be a consequence of specific inactivation of helper cells.
Subpopulations of T lymphocytes from human blood differing in density and stage of maturation
Authors: van de Griend René J. , Astaldi Giulia C. B. , van den Ende Abraham , Loos Johannes A. , Roos Dirk 
Published: February 2007

AbstractPrevious investigations have shown that peripheral lymphocytes with a low specific gravity are much more active than are heavy lymphocytes in the proliferative response towards mitogens, antigens and allogeneic lymphocytes. We have now studied the biological significance of this difference in human peripheral T lymphocytes with two independent parameters generally regarded as maturation criteria.Heavy human T lymphocytes contain about one‐third of the amount of cyclic AMP found in light T cells, but the increase in cyclic AMP produced by isoproterenol or prostaglandin E1 is much higher in the heavy T cells. The lactate dehydrogenase isoenzyme pattern of heavy human T lymphocytes is intermediate between that of human thymocytes and light T lymphocytes, the latter showing the most mature pattern. A high correlation was found between these two parameters, the cell density and the reactivity towards phytohemagglutinin.We conclude that human peripheral T lymphocytes are heterogeneous in maturation level: heavy, nonreactive T lymphocytes are less mature than light T lymphocytes.
Suppression of the immune response to altered self induced by immunogenic and nonimmunogenic altered self structures
Authors: Ramos Teresa , Möller Erna , Möller Göran 
Published: February 2007

AbstractFluorescein (FITC)‐haptenated mouse spleen cells are capable of inducing a B cell immune response characterized by the production of antibodies directed against hapten‐altered self structures. The induction of this response is thymus‐independent and strictly dependent on the hapten concentration used for labeling the cells.Pretreatment of mice with immunogenic, labeled spleen cells strongly suppressed the plaque‐forming cell response to a subsequent challenge with FITC‐labeled spleen cells, sheep (SRC) or horse (HRC) red cells labeled with the same hapten and native FITC‐dextran.Mice primed with lightly haptenated (nonimmunogenic) cells 7 days before challenge were completely unresponsive to the immunogenic dose of labeled cells and displayed a significantly reduced response to FITC‐SRC or FITC‐HRC. However, the response to FITC‐dextran was enhanced, as compared to unprimed animals.The concept of immunogenic vs. nonimmunogenic requirements of an antigen to induce unresponsiveness, and the specificity of the B cell clones affected by suppression is discussed.
Correlated expression of VH framework and VHidiotypic determinants on T helper cells and on functionally undefined T cells binding group A streptococcal carbohydrate
Authors: Eichmann Klaus , Ben‐Neriah Yinon , Hetzelberger Doris , Polke Christine , Givol David , Lonai Peter 
Published: February 2007

AbstractAntibodies to framework determinants of the VH and Vλ. fragments of MOPC 315 and antisera to the VH idiotype determinants of the A 5 A antibody were used to analyze the antigen receptors of mouse T (and B) cells. This was done by using the antibodies as inhibitors in (a) an assay in which the binding of radiolabeled streptococcal carbohydrate (A‐CHO) antigen by primed and unprimed T and B cells is determined and (b) an assay in which the helper activity of group A streptococcal vaccine‐primed T cells is determined. The results suggest that the major proportion of primed and unprimed T cells binding A‐CHO (70–9076) exhibit VH framework and VH idiotypic determinants. This population appears to include the helper T cells. A minor proportion of T cells (10–3076) express Vλ‐related framework determinants and lack VHframework and VH idiotypic determinants. This population does not include T helper cells. Taken together, the data suggest that a subpopulation of T cells, including the helper cells, uses entire Ig VH regions as part of their antigen receptor system.
Microsequence analysis of Ia antigens from three strains of rats
Authors: Cecka J. Michael , Blankenhorn Elizabeth P. , Götze Dietrich , Hood Leroy 
Published: February 2007

AbstractHomologues of Ia antigens of the mouse are identified in three rat strains by partial N‐terminal amino acid sequence analysis. Ia antigens of the rat were isolated by indirect immune precipitation using specific rat alloantisera. Rat Ia antigens consist of two components, α and β, which have respective mol. wts. of approximately 35000 and 28 000. Partial N‐terminal sequence analysis of each of the αa components of the H‐la, H‐1l and H‐1n haplotypes yields a single, apparently homogeneous sequence which is identical among the three haplotypes and is strikingly homologous to the a polypeptides of the I‐E subregion of mouse and to the human polypeptide, p34. Partial N‐terminal sequence analysis of the β components shows that a mixture of polypeptides is present for each haplotype. There are differences in the β sequences among the three haplotypes and potential homologies between the rat β sequences and the sequences of the β polypeptides of the I‐A and I‐E subregions of mouse. These observations imply that the rat has at least two distinct groups of Ia molecules. The organization of genes encoding the Ia polypeptides in the major histocompatibility complex of the rat is discussed.
Fc receptors on rabbit lymphocytes Existence of receptors for IgG antibody complexed with antigen; conditions for its detection
Authors: Bast Bert J. E. G. , Manten‐Slingerland Ria , Roholl Paul , Meyling Frits Gmelig , Ballieux Rudy E. 
Published: February 2007

AbstractThe presence of Fc receptors (FcR) on rabbit peripheral blood leukocytes is demonstrated using rosette formation with an ox erythrocyte‐antibody (EoxA) complex. The receptor is specific for the Fc fragment of IgG (neither IgM nor F (ab′)2anti‐Eox mediates rosette formation) that is antigen‐bound (aggregated rabbit IgG inhibits the rosette formation only transiently). The receptor is species‐specific: guinea pig IgG/ Eox, goat IgG/Eox and sheep IgG/Eox complexes do not show rosette formation, and goat IgG aggregates do not inhibit rosette formation.The origin of the target erythrocytes is of importance. Sheep erythrocytes are not useful, and within Eox large differences between donors were found. Rosette formation was only inhibited by pretreatment of the rosette‐forming cells with homologous immune complexes, whereas the size of the antigen greatly influenced the degree of inhibition. The rabbit FcR is pronase‐resistant, unlike the human and murine FcR. The interaction of IgG and the FcR is not inhibited by isolated Cγ 3 domains. Further evidence for the requirement of the whole Fc region was obtained in experiments where inhibition of the rosette formation was observed using antisera directed to the Cγ3 and the Cγ2 domain, respectively. Anti‐Fab antiserum did not inhibit rosette formation. Results are discussed in relation to the mechanism of allotypic suppression.
Fc receptors on rabbit lymphocytes. Identification and organ distribution of rosette‐forming cells; cocapping with surface immunoglobulin
Authors: Bast Bert J. E. G. , Manten‐Slingerland Ria , Roholl Paul , van Graft Marja , Ballieux Rudy E. 
Published: February 2007

AbstractFc receptor (FcR)‐bearing cells were demonstrated using ox erythrocytes coated with homologous IgG‐type antibodies (EAY) in rabbit peripheral blood leukocytes (PBL) and in various lymphoid organs.Discrimination of the rosette‐forming cells (RFC) is carried out after prior ingestion of tetramethylrhodamine isothiocyanate‐labeled latex particles and in transmission electron microscopic studies. Most of the nonlymphoid cells (5‐10%) in PBL and spleen cell suspensions expose FcR. These nonlymphoid cells are almost absent in other lymphoid organs, except in bone marrow. The average percentage of cells rosetting with IgG‐sensitized erythrocytes (EAγRFC) in lymphoid cell preparations of the various tissues was as follows: PBL 25%, bone marrow 65%, appendix 37%, spleen 40%, Peyer's patches 44%, thymus 2% and peripheral lymph node 27%.The nature of FcR‐bearing PBL was further studied using F(ab′)2 anti‐IgM, anti‐IgA or anti‐T cell conjugates. About half of the population of B cells, bearing IgM or IgA, express FcR. Moreover, about 80% of the RFC are found within the B cell population. Only a few T cells were found rosetting with EAγ suggesting that most of the non‐B lymphoid RFC are “null” cells. In different lymphoid organs, the percentages of EAγRFC and B cells are comparable but not identical. A greater part of the EAγRFC also expresses the receptor for the third component of complement. After capping of membrane IgM determinants, FcR is located in the same cap on the majority (60%) of the FcR‐positive IgM‐capped cells.
Thymus cell migration: Quantitative aspects of cellular traffic from the thymus to the periphery in mice
Authors: Scollay Roland G. , Butcher Eugene C. , Weissman Irving L. 
Published: February 2007

AbstractWe have used intrathymic injection of fluorescein isothiocyanate to label thymocytes in situ. The method gives random labeling of the thymocyte population and so can be used to quantitate the extent of migration of cells from the thymus to the periphery. Migrant cells can be visualized in frozen sections or cell suspensions of peripheral organs by their fluorescence.Our data show that in young adults, about 1% of thymocytes leave the thymus per day. Since the bulk of thymocytes turn over every 5 to 7 days, this indicates that the vast majority (95%) of thyrnocytes die within the thymus. Cells that do leave the thymus, go mainly to the T areas of lymph nodes, spleen and Peyer's patches. Migrants are extremely rare in bone marrow, gut and liver. Migration is about the same in neonates as in adults relative to the size of the thymus, but is considerably lower in older animals where it is only about 0.1% of thymocytes per day at the age of six months.
Dissociation between interferon production induced by phytohemagglutinin and concanavalin A in spleen cell cultures of nude mice
Authors: Kirchner Holger , Fenkl Herbert , Zawatzky Rainer , Engier Helmut , Becker Hans 
Published: February 2007

AbstractSpleen cells of homozygous nude mice did not react with lymphoproliferation to both phytohemagglutinin (PHA) and concanavalin A (Con A), and there was no detectable interferon production in response to Con A. However, PHA‐induced interferon production was equal in spleen cells of nuinu mice and nu/+ mice. One possible explanation for these findings is that a subset of T cells responds to PHA with interferon production different from that responding to Con A with interferon production.
Presence of receptors for IgA on human T and non‐T lymphocytes
Authors: Sjöberg Olof 
Published: February 2007

AbstractLatex particles coated with human IgA were used to detect the presence in human blood of lymphocytes capable of binding IgA. It was necessary to culture the lymphocytes in medium without IgA before the assay. A small percentage of both T and non‐T cells had IgA receptors. The receptors were distinct from those binding to IgG or IgM.
Antibodies to immunoglobulin heavy chain variable regions protect helper cells from specific suicide by radiolabeled antigen
Authors: Puri Joseph , Ben‐Neriah Yinon , Givol David , Lonai Peter 
Published: February 2007

AbstractThe antigen‐binding receptor of helper T cells was studied by radioactive antigen‐ caused suicide in vitro. Purified antibodies to immunoglobulin variable regions, obtained from sera of rabbits immunized with isolated VH and VL fragments of mouse myeloma proteins (MOPC 315, XRPC 25), were used to inhibit the binding of radiotoxic antigen. Anti‐VH, but not anti‐Vγ, or anti‐Vχ, inhibited suicide of carrier‐ primed cells.
The binding of soluble immune complexes of guinea pig IgG2 to homologous peritoneal macrophages Determination of the avidity constants at 4 °C.
Authors: Leslie Robert G. Q. 
Published: February 2007

AbstractSoluble immune complexes of guinea pig IgG2 anti‐DNP (2,4‐dinitrophenyl) antibodies and DNP19BSA (bovine serum albumin) were prepared at a variety of antibody‐to‐antigen ratios. The mean sizes of the complexes were determined by gel filtration, and equilibrium binding of the complexes to homologous peritoneal macrophages was measured at 4°C. Scatchard plots of the binding data were linear indicating that the complexes were binding to a uniform population of functionally independent membrane receptors.The avidity constants for complex binding to macrophages increased from 15.4 × 107 M−1 for complexes containing an average of two antibody molecules to 59.0 × 107 M−1 for complexes containing an average of four, compared with an association constant for monomeric IgG2 of 0.21 × 107 M−1. Calculation of the molar‐free energy changes accompanying monomer and immune complex binding revealed not only that the intrinsic binding activity of mononer was sufficient to account for the complex binding activities by simple cooperation of linked antibodies, but also that the cross‐ linking of antibodies with antigen imposed a strain on the antibody‐receptor interaction, resulting in complex binding energies that were lower than the values expected from a simple cooperative mechanism.Complex inhibition by monomeric IgG2 of unrelated antibody specificity was studied, and it was observed that high concentrations of monomer led to an increase in macrophage discrimination between complexes of different size. The relevance of this finding to the in vivo clearance of circulating complexes is discussed.
Active and passive re‐expression of Fcγ receptors on human lymphocytes
Authors: Samarut Christiane , Revillard Jean‐Pierre 
Published: February 2007

AbstractModulation of receptors for IgG (FcγR) on human lymphocytes was induced by the interaction with erythrocyte‐IgG antibody (EAG) complexes followed by incubation at 37°C. The re‐expression of FcγR could be achieved by two independent processes, (a) Active synthesis, susceptible to inhibition by puromycin or cycloheximide was shown to peak 4 to 6 h after removal of EAG complexes; it required addition of at least 2% fetal calf serum. (b) Insertion of soluble FcγR into the membrane of modulated lymphocytes was shown to occur within 20 min of contact between cells and FcγR‐containing supernatants; it was not altered by protein synthesis inhibitors. FcγR‐like material, spontaneously released by unstimulated peripheral blood lymphocytes or by polymorphonuclear cells, was taken up by modulated lymphocytes. This soluble material was fully absorbed on polymerized human IgG; it was non‐ dialyzable, thermolabile (56 °C, 30 min) and partially destroyed by freezing and thawing; it was recovered as two broad peaks from chromatography on polyacrylamide gel; it was shown to bind to both T and non‐T FcγR‐bearing lymphocytes capable of forming EAG rosettes before modulation; and it could be inserted into allogeneic lymphocytes. These results demonstrate that the FcγR structure bears two active sites, one binding to the Fcγ and the other to the surface of EAG rosette‐forming cells. Rapid release of soluble FcγR from the cells and their possible insertion into the membrane may have important implications with respect to the biological functions associated with these receptors.
Multiple H‐2 and non‐H‐2 genes controlling the anti‐lysozyme response: Alternative gene constellations can lead to responsiveness
Authors: Hill Sharon W. , Kipp Dale E. , Melchers Inga , Frelinger Jeffrey A. , Sercarz Eli E. 
Published: February 2007

AbstractMice carrying the H‐Zb and H‐2s haplotypes are genetically nonresponsive to hen egg‐white lysozyme (HEL). Analysis of the anti‐HEL response patterns of F1, F2 and backcross progeny showed that responsiveness was dominant and H‐2‐linked. From plaque‐forming cell and serum assays in intra‐H‐2 recombinant mice, it was established that two I loci were implicated, the possession of either leading to responsiveness to HEL. One of the I genes maps in I‐A, and the second in I‐C, S or G. While the nonresponse phenotype was determined by the H‐2 haplotype, there were codominant non‐H‐2 genes which contributed to a severe reduction in the level of antibody produced in responder strains. A model is presented attributing the outcome of an encounter with HEL to the regulatory balance of helper and suppressor T cells, which have been activated by different subregions of the major histocompatibility complex.
Enhancement of the primary antibody response by 2‐mercaptoethanol is mediated by its action on glutathione in the serum
Authors: Hoffeld J. Terrell , Oppenheim Joost J. 
Published: February 2007

Abstract2‐Mercaptoethanol (2‐ME) is widely used in rodent lymphoid cell cultures as an enhancer of multiple cellular functions. We have confirmed that the action of 2‐ME must be on a serum component(s), rather than a direct action on the cells. The serum component(s) is contained within the dialyzable fraction of fetal calf serum (FCS) since: (a) dialysis of FCS diminished the ability of FCS to support an antibody response even in the presence of 2‐ME; and (b) FCS dialysate, pulsed with 2‐ME, restored the ability of dialyzed FCS to support an antibody response. Diminution of the reduced glutathione content of FCS by heating reduced the capacity of FCS to support an antibody response, whereas addition of 2‐ME‐pulsed glutathione restored the supportive capacity of heated FCS. Conversely, oxidized glutathione inhibited the antibody response in the absence of 2‐ME, but that inhibition was not seen in the presence of 2‐ME. We have concluded that reduced glutathione is an essential component in FCS in order for 2‐ME to produce its enhancing effect. The most plausible explanation for the enhancement of antibody responses, in vitro, by 2‐ME is the concomitant reversal of the inhibitory effect of oxidized glutathione and the increased availability of reduced glutathione which can scavenge oxygen‐derived radicals, thus protecting macrophages and lymphocytes from the deleterious effects of oxygen‐derived free radicals.