bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of proteolytic (C 3‐cleaving) activity on mouse mastocytoma (P815) cells and other mouse cell lines by formation of cell contact with C 3‐carrying mouse lymphocytes
Authors: Dierich Manfred P. , Schulz Thomas , Yefenof Eitan , Kiein George 
Published: February 2007

AbstractMouse mastocytoma cells (P815) formed rosettes with normal mouse spleen lymphocytes which had been coated with uncleaved human C 3; this interaction was clearly dependent on the amount of C 3. Lymphocytes treated with C 3 b or buffer alone were ineffective. Formation of cell contact could be inhibited by the presence of protease inhibitors such as diisopropyl fluorophosphate, phenyl methyl sulfonyl fluoride and tosyllysyl chloromethyl ketone. Seven out of 13 different cell lines behaved like P 815 cells.The results strongly suggested that a proteolytic activity on mouse tumor cells led to a cooperation with uncleaved C3 on a carrier cell to connect these two cells. We interpreted these data in analogy to the complement‐dependent bridge formation mechanism (M. P. Dierich and B. Landen, J. Exp. Med. 1977. 146: 1484): uncleaved C3, attached to mouse spleen lymphocytes as carriers, becomes cleaved by enzymes associated with the tumor cells tested; by this cleavage, the labile binding site is released on C3 (nascent C3b) and anchors the C3‐carrying cell to the protease‐ carrying cell; since this labile binding site is short‐lived, this process can be induced by membrane‐associated proteases only. The nature of the proteases and the biological implications of this process are as yet uncertain.
Surface markers on natural killer cells of the mouse
Authors: Habu Sonoko , Hayakawa Kyoko , Okumura Ko , Tada Tomio 
Published: February 2007

AbstractRabbit antiserum against mouse brain tissue (anti‐brain‐associated T cell antigen, anti‐BAT) was capable of killing splenic natural killer (NK) cells of CBA/J, BALB/c, C 57 BL/6 J, C 3 H/He and nude mice, which were detected with Molony virus‐induced lymphoma (YAC‐1) and radiation‐induced leukemia (RL ♂ 1) cells as targets. The same antiserum abolished T cell functions, e.g. carrier‐specific helper function and the responsiveness to concanavalin A, but not B cell functions, e.g. immunological memory for the secondary antibody response and the responsiveness to lipopolysac‐ charide. After absorption of the anti‐BAT with thymocytes, the ability to kill T cells was completely abrogated, leaving the activity to kill NK cells intact. No other heterologous and isologous antisera, i.e. rabbit anti‐mouse thymocyte antiserum, goat antiserum against antigens shared by thymus and B cells, anti‐Thy‐1.2 and anti‐la antisera, could eliminate NK function regardless of their definite reactivity against T or B cells. The results indicate that the absorbed anti‐BAT can distinguish NK cells from other known subsets of T and B cells.
Markers of macrophage heterogeneity. I. Studies of macrophages from various organs of normal mice
Authors: Roubin Regine , Zolla‐Pazner Susan 
Published: February 2007

AbstractA unique subpopulation of macrophages (MΦ) was identified among the spleen and bone marrow MΦ of normal mice. After 24 h of culture, approximately 2.5% of the adherent cells cluster into “foci” of 10–30 cells. On the basis of their phagocytic and morphologic characteristics, these focus‐forming MΦ (FF‐MΦ) appeared to be highly activated. Uncoated sheep erythrocytes (E) were ingested by FF‐MΦ indicating that opsonization was not a prerequisite for phagocytosis. However, IgM‐coated E (EIgM) were more readily phagocytosed by FF‐MΦ than were E suggesting that IgM is recognized as an effective opsonin by these cells. EIgM and E coated with IgM and complement(C) (ElgMC) were ingested by approximately the same percentage of FF‐ MΦ; thus, if these cells possess complement receptors in addition to structures which bind EIgM, the C receptors do not enhance the ability of FF‐MΦ to ingest opsonized particles.The non‐focus‐forming MΦ, e.g. individual MΦ (I‐MΦ), in the spleen and bone marrow can, themselves, be divided into various subpopulations distinguished by their ability to bind and ingest E, EIgM and ElgMC. These may represent various subpopulations of MΦ or MΦ at various stages of activation or differentiation.While spleen and bone marrow MΦ contained FF‐MΦ and I‐MΦ which vary in their ability to ingest E, EIgM and ElgMC, the MΦ of the peritoneum and blood of normal mice were far more homogeneous. Peritoneal and blood MΦ did not form foci, and did not ingest E or EIgM in significant amounts although a small percentage were able to ingest ElgMC. These data suggest that the population of MΦ in the spleen and bone marrow are far more heterogeneous than those found in the peritoneum or blood and that binding and phagocytosis of various coated and uncoated erythrocytes can be studied to elucidate this heterogeneity.
Identification of TL+ thymocytes with different Lyt phenotypes
Authors: Kisielow Paweł , Dráber Petr , Wysocka Maria 
Published: February 2007

AbstractThe surface antigenic phenotype of BALB/c thymocytes has been analyzed by sequential cytotoxic treatment with Lyt‐1.2, Lyt‐2.2 and TL.2 antisera plus complement. Two new minor subpopulations with TL+Lyt‐l+2− and TL+Lyt‐l−2+ phenotypes have been identified providing direct evidence for the heterogeneity of the Lyt phenotype among the TL‐positive supopulation of thymocytes. This finding suggests that differentiation pathways of Lyt subsets of T cells are more complex than originally proposed and that commitment to separate lines of differentiation may occur already at the level of immature, cortical thymocytes.
Chemiluminescence and immune cell activation II. Enhancement of concanavalin A‐induced chemiluminescence following in vitro preincubation of rat thymocytes; dependency on macrophage‐ lymphocyte interaction
Authors: Wrogemann Klaus , Weidemann Maurice J. , Ketelsen Uwe‐Peter , Wekerle Hartmut , Fischer Herbert 
Published: February 2007

AbstractThe immediate chemiluminescence (CL) response to concanavalin A (Con A) of rat thymocytes is enhanced 10 to 20‐fold when the cells are preincubated in serum‐free medium for 5–20 h. During this period, multiple encounters between lymphocytes and macrophages occur which morphologically appear as rosettes or grape‐like cell aggregates. Addition of bone marrow‐derived macrophages increases the number of cell aggregates and also the CTL response to Con A. Paradoxically, removal of macrophage‐containing cell aggregates after cocultivation leaves a pure thymocyte population which strongly responds to Con A with CL.Our results confirm that macrophage‐depleted “competent” lymphocytes are capable of CL and, furthermore, that “competence” is gained during cocultivation with macrophages. We are therefore convinced that measurements of macrophage and lymphocyte CL are a powerful tool for further elucidation of lymphocyte differentiation and of interactions between macrophages and lymphocytes.
Generation of cytolytic T lymphocytes in vitro. O XI. Accessory cell requirement in secondary responses to particulate alloantigen
Authors: Degiovanni Gérard , Cerottini Jean‐Charles , Brunner K. Theodor 
Published: February 2007

AbstractThe non‐T accessory cell requirement for cytolytic T lymphocyte (CTL) generation in vitro was studied in a system which makes use of particulate membrane preparations as a source of alloantigen, and spleen cells from alloimmune mice as a source of responding cells. It is shown that removal of nylon‐adherent cells from the responding cell population strongly reduced CTL generation, whereas direct removal of Ig+, phagocytic or plastic‐adherent cells had no effect. The CTL response of the nylon‐ nonadherent cell population could be reconstituted by the addition of normal spleen cells, which by themselves do not generate CTL in response to particulate alloantigen. The accessory cell function of normal spleen cells was not affected by depletion of T cells or of phagocytic cells, but was sensitive to γ‐irradiation (1000 rd). The system thus demonstrates the requirement for a nylon‐adherent accessory cell population in the secondary CTL response to particulate alloantigens which does not exhibit the typical characteristics of T cells, B cells or macrophages.
Evidence of the presence in normal serum of a carrier of the serum thymic factor (FTS)
Authors: Dardenne Mireille , Pléau Jean‐Marie , Bach Jean‐François 
Published: February 2007

AbstractChromatography of normal human or mouse serum on Sephadex G‐150 revealed the presence of two peaks of activity in the rosette assay used for the characterization of the serum thymic factor (FTS). one peak corresponded to the elution volume of FTS (mol. wt. 867), the other to molecules with mol. wts. of 40000–60000. Both peaks were absent in serum of thymectomized (Tx) mice but could be induced in such Tx mice by injection of synthetic FTS. Study of the biological half‐life of both peaks (assessed by the rosette assay) and demonstration of their specific retention on anti‐ FTS immunosorbent indicate, altogether with direct binding experiments, that FTS is transported in serum by a molecule with a mol. wt. of the order of that of albumin or prealbumin. It is apparent that FTS bound to this molecule is responsible for the biological FTS‐like activity associated with large mol. wt. fractions of normal serum.
Mechanism of T cell activation I. A screening of “step one” ligands
Authors: Larsson Eva‐Lotta , Coutinho Antonio 
Published: February 2007

AbstractA number of ligands which bind to T cell surfaces were screened on murine spleen cells for their functional ability to induce either of the two necessary steps in the process of T cell triggering: (a) expression of growth receptors by T lymphocytes and (b) production of T cell growth factors in cultures containing both T cells and accessory cells. Among four lectins tested, concanavalin A was found to induce both responses but is primarily a “step 2” ligand, in particular at low concentrations; leucoagglutinin was the most potent “step 1” ligand with very limited “step 2” activity; wheat germ agglutinin and soybean lectin were inactive. Direct mitogenicity of the lectin to normal spleen cell cultures was limited by the poorest of these two functional properties. A number of rabbit anti‐lymphocyte antisera, anti‐Thy‐1 alloantisera, anti‐H‐2 and anti‐Ia monoclonal antibodies, as well as complexes of rabbit IgG, were all found to be devoid of “step 1” activity, and consequently, non‐ mitogenic for spleen cells. In contrast, a rabbit anti‐mouse brain antiserum, although also devoid of mitogenicity, was found to be capable of “step 1” induction.These results suggest that not all rearrangements of T cell surface membrane components upon binding of a ligand result in the functional expression of growth receptors. This appears to be the result of selective interactions with specific sites which include structures binding to concanavalin A, leucoagglutinin and rabbit anti‐mouse brain antibodies.
Biochemical characterization of an Fc receptor of rabbit lymphocytes
Authors: Sire Joséphine , Kahn‐Perles Brigitte , Collé Allain , Bourgois Alain 
Published: February 2007

AbstractIsolation of Fc‐binding molecules was performed by complexing IgG antibodies and the corresponding antigens in lysates of radiolabeled rabbit lymphoid cells. A single‐ chain molecule of 110000 apparent mol. wt. (unreduced) or 120000 (reduced) was observed in sodium dodecyl sulfate polyacrylamide gel electrophoresis when the antibodies were in the IgG form but not as F (ab′),. This molecule was very susceptible to proteolysis, but the fragments thus produced remained associated by disulfide bridges, and the binding properties of the molecule were conserved. The molecule and its proteolytic fragments (mol. wts. 75 000, 45 000 and 20 000) were very similar to those obtained for the mouse Fc receptor under similar conditions, and therefore the molecule was designated as rabbit Fc receptor. Among several precipitating systems used, some Ig‐anti‐Ig complexes appeared to be the most efficient in co precipitating the rabbit Fc receptor. Remarkably high titers of Fc receptor were found on lymphocyte membrane of infected rabbits, in agreement with a possible role of this molecule in immune regulation.
Two major idiotypes in mouse anti‐(4‐hydroxy‐3‐nitrophenyl)acetyl (NP) antibodies are controlled by “allelic” genes
Authors: Karjalainen Klaus 
Published: February 2007

AbstractAnti‐NP [(4‐hydroxy‐3‐nitro‐phenyl)acetyl)] antibodies from the primary response of BALB/c mice contain a major idiotype NP‐a that is controlled by an allotype‐linked gene VHNPa. A new strain distribution pattern for a VH marker was discovered: strains BALB/c, RF, DBA, RIII and SM were positive, and strains C57BL/6, SJL, CBA, A/J, CE, AKR and NZB were negative for the idiotype NP‐a.NP‐a idiotype shared many characteristics with previously described idiotype NP‐b and, therefore, allelism was suggested between them. Both idiotypes have γ light chains, both seem to be conservative in evolution, both are predominant early in the antibody response. Later during the response, antibodies become increasingly idiotype‐negative while at the same time, homogeneous isoelectric focusing patterns become very heterogeneous. The study of VH recombinant strains supported the concept of allelism because in every case studied, the idiotypes were mutually exclusive. (C57BL/6 × BALB/c)F1 mice expressed idiotypes NP‐a and NP‐b regularly and in approximately equal amounts.
Monoclonal antibodies to hemagglutinin and to H‐2 inhibit the cross‐reactive cytotoxic T cell populations induced by influenza
Authors: Askonas Brigitte A. , Webster Robert G. 
Published: February 2007

AbstractThe target antigens recognized by the cross‐reactive population of cytotoxic T cells on A/USSR/90/77 (H 1N 1) influenza virus‐infected cells was studied with monoclonal antibodies to the H‐2k antigen and viral hemagglutinin. The cytotoxic killing of virus‐ infected cells was differentially inhibited by three monoclonal antibodies to H‐2k. Synergistic inhibition of cytotoxic activity was obtained with monoclonal antibodies to H‐2 and to some antigenic determinants on the hemagglutinin melecule of A/USSR but not with others. Since target cells infected with other subtypes of influenza A viruses were not inhibited by any of the monoclonal antibodies to AIUSSR hemagglutinin, it is suggested that the sites recognized by the cross‐reactive cytotoxic T cells were satirically inhibited by the anti‐A/USSR monoclonal antibodies. The results suggest that at least one of the target antigens recognized by the cross‐reactive population of cytotoxic T cells is located on the hemagglutinin molecule. The present observations are in agreement with cytotoxic T cell recognition of closely situated viral and H‐ 2 determinants.
Delayed‐type hypersensitivity induced by antigen pulsed, bone marrow‐derived macrophages
Authors: Mottram Patricia L. , Miller Jacques F. A. P. 
Published: February 2007

AbstractMouse bone marrow cells, cultured in specifically conditioned medium, were found to be virtually pure macrophages after 7 days. When pulsed with antigen, these cells induced and elicited delayed‐type hypersensitivity (DTH) with the same efficiency and major histocompatibility complex restrictions as antigen‐pulsed peritoneal exudate cells. Both of these macrophage populations had 20% Ia+ cells, as measured by complement‐mediated cytotoxicity. When most of the Ia+ cells were removed, the remaining antigen‐pulsed macrophages could not elicit DTH in sensitized mice.
Presence of multiple isotypes on the surface of human tonsillar lymphocytes
Authors: Vessière‐Louveaux Françoise M. Y. R. , Hijmans Willy , Schuit Henrica R. E. 
Published: February 2007

AbstractFormaldehyde‐fixed small lymphocytes from human tonsils were investigated for the presence of the Ig heavy chain class isotypes α, γ, δ and μ on their membranes by means of a direct immunofluorescence technique. About 50% of the small lymphocytes were defined as B cells with an anti‐Fab antiserum. Most of the B lymphocytes carried more than one isotype on their membrane, and all combinations of two isotypes were observed. The existence of three or four isotypes on the membrane of individual lymphocytes was deduced. The sIgD, sIgM and sIgA, sIgD, sIgM combinations were the most common. The isotypes were present as separate molecules since they showed independent distribution patterns under capping conditions.
Macrophage handling of soluble immune complexes ingestion and digestion of surface‐bound complexes at 4, 20 and 37 °C
Authors: Leslie Robert G. Q. 
Published: February 2007

AbstractRadioassays have been developed to measure, as separate events, the ingestion and degradation of macrophage‐bound guinea pig IgG anti‐DNP (2,4‐dinitrophenyl)‐ DNP‐BSA (bovine serum albumin) complexes of defined size and subclass. Complex ingestion was observed to be temperature‐dependent and was effectively blocked only by a combination of inhibitors of respiration and glycolysis indicating that the process is under the same metabolic control as fluid phase pinocytosis. On the other hand, the half‐life of membrane‐bound complexes at 37 °C (t1/2 = 5.6 ± 1.7 min) was considerably shorter than the value expected from membrane turnover studies (t1/2 = 22.4 min) suggesting that complexes are selectively cleared from the cell surface. The rate of ingestion at 20°C was independent of complex size and of the IgG subclass used in complex formation, but was affected by in vivo stimulation of the macrophages before assay.Complex digestion was shown to be highly temperature‐dependent and, at 37 °C, proceeded at a rate (t1/2 = 1.5‐5 h) which was 20‐60‐fold slower than the rate of ingestion indicating that the latter is unlikely to influence digestion kinetics. On the other hand, the selective action of 2‐deoxyglucose in blocking digestion, but not ingestion, suggests that pinosome‐lysosome fusion may play a part in determining the overall catabolic rate. A 2 to 3‐fold difference in digestion rates was observed between the proteins employed as antibody (guinea pig IgG1 or IgG2) and as antigen (DNP‐BSA). This finding suggests that the intrinsic susceptibility of ingested proteins to enzymatic hydrolysis may be the prime determinant of digestion rate. As with ingestion, no discrimination was observed in the degradation of complexes of different size or IgG antibody subclass.The observations in this and the preceding study (Eur. J. Immunol. 1980. 10: 317) indicate that complex size is important in determining the level of uptake by phagocytes but not subsequent events associated with catabolism.
Induction of susceptibility to HgCl2 immune glomerulonephritis in the Lewis rat by immunocompetent cells from susceptible F1 hybrids
Authors: Sapin Catherine , Druet Philippe , Mandet Chantal 
Published: February 2007

AbstractSusceptibility to HgCl2‐induced glomerulonephritis was transferred to resistant Lewis (LEW) rats, irradiated and reconstituted with (LEW × BN)F1, hybrid immunocompetent cells. This glomerulonephritis was similar to that observed in Brown‐Norway (BN) rats with a first stage characterized by anti‐glomerular basement membrane antibodies and a second stage with immune complex‐type deposits in the glomerular tufts and in the small renal arteries.
Immune interferon secretion as an expression of immunological memory to transplantation antigens: in vivo generation of long‐lived, recirculating memory cells
Authors: Virelizier Jean‐Louis , Guy‐Grand Delphine 
Published: February 2007

AbstractLeukocytes from C57BL/6 mice immunized against DBA/2 strain antigens by intraperitoneal injection of mastocytoma P 815 cells produced, when stimulated in the mixed leukocyte reaction assay with DBAI2 spleen cells, an earlier and more intense secretion of immune interferon than leukocytes from untreated mice. This secondary‐type interferon response was independent of cell proliferation. The memory phenomenon was induced by long‐lived, recirculating lymphocytes found in spleen, lymph nodes and thoracic duct, but not in the thymus. Memory cells could be recruited into inflammatory sites. They were shown to be specific for H‐2 alloantigens, although some cross‐reactivity with stimulating cells bearing unrelated H‐2 antigens was observed. The possible anti‐tumor, antiviral and immunoregulatory roles of this memory phenomenon, and its significance in transplantation immunity are discussed.
Separation of memory cell subpopulations by complement receptors: in vivo analysis
Authors: Feldbush Thomas L. 
Published: February 2007

AbstractThe appearance of complement receptors (CR) on memory B cells was used as a measure of memory cell maturation. At various times after priming, lymphocytes were separated by rosette formation (EAC‐RFC) and Ficoll‐Hypaque separation followed by transfer to carrier‐primed, irradiated recipients. The relative contribution of the CR+ and CR− memory cells to the total memory cell response was then calculated using the amount of antibody produced, corrected for the yield and number of B cells in each fraction. Using this technique, the following results were obtained: (a) in agreement with other investigators, the mature memory cell population is composed of both CR+ and CR− cells; (b) early after immunization (2 and 4 weeks), the predominate memory cell population is CR−, while later (6 to 8 months) the CR+ cells can contribute an average of 50% of the response; (c) at all times tested, the CR− B cell population was greatly enriched for memory cell activity, and (d) the shift from CR+ to CR− by some of the memory cells seemed to accompany a change in cell size.
Sendai virus stimulates chemiluminescence in mouse T and B lymphocytes
Authors: Peterhans Ernst , Mundy Janice , Parish Christopher R. 
Published: February 2007

AbstractMouse spleen cells emit a burst of chemiluminescence (CL) starting within a few seconds on infection with Sendai virus. We have analyzed the cell types responsible for the generation of CL in the spleen cell population. Cell suspensions, treated with iron carbonyl powder to remove adherent cells, showed similar CL compared to untreated spleen cells suggesting that lymphocytes, rather than phagocytic cells, were responsible for CL generation. Furthermore, killing of T lymphocytes with anti‐ Thy‐1.2 antibody and complement, and removal of Ig+ cells from the cell population, respectively, showed that both T and B lymphocytes are active in CL generation. The results suggest that changes in lymphocyte metabolism occur within the first few minutes of cell‐virus contact.
Preferential retention of human chromosome 14 in mouse × human B cell hybrids
Authors: Crocem Carlo M. , Shander Monica , Martinis Joanne , Cicurel Lucienne , D'ancona Gian G. , Koprowski Hilary 
Published: February 2007

AbstractLoss of human chromosomes from mouse × human hybridomas is not random. Human chromosomes 14, 5 and 22 are preferentially retained, while chromosomes 2 and 1 are preferentially lost. Interestingly, human chromosome 14, which carries the genes for human immunoglobulin heavy chains, appears to be retained by almost all the hybrid clones and subclones.