bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunoglobulin‐bearing lymphocytes of the chicken. I. Heavy chain immunoglobulin commitment and organ distribution
Authors: Hudson L. 
Published: February 2007

AbstractWhen purified anti‐immunoglobulin light chain antibodies were used in indirect immunofluorescence or labeled with 125I for autoradiographic staining, a similar percentage of Ig‐bearing lymphocytes were detected by both techniques in lymphoid cell suspensions from the thymus or blood of 8–14‐week‐old chickens. However, a larger proportion of Ig positive lymphocytes were detected in suspensions of bursal cells by the more sensitive autoradiographic method, suggesting a lower surface density of Ig: perhaps on newly differentiated stem cells. In thymus and spleen suspensions, the proportions of Ig positive lymphocytes carrying μ and γ‐chains were roughly equal, whereas in the B cell populations of the bursa and blood, cells carrying surface γ‐chains predominated. IgA‐bearing lymphocytes were only a minor population (<5%) in lymphocyte suspensions prepared from the thymus, bursa, blood and spleen of adult chickens, but formed almost 50% of the Ig‐bearing lymphocytes in the caecal tonsils.
Suppression of immune responses to sheep red cell antigens in rats preimmunized with heterophilic antigen: cellular events
Authors: Hellering I. , Stern K. 
Published: February 2007

AbstractDepression of humoral immune response to sheep red cells (SRC) has been observed in rats previously immunized with heterophilic (Forssman) antigen. Analogous phenomena were observed by assay of splenic plaque‐forming cells obtained from rats immunized in vivo with heterophilic antigen (HA) and challenged with SRC. Isophilic immune responses were almost completely suppressed. Kinetics of the primary and secondary immune responses were analyzed. Intervals of two to four days between administration of HA and SRC yielded maximal suppression. Primary immune responses to SRC were determined in cultures of splenic cell suspensions derived from rats which had been either injected in vivo with HA or received no treatment. Under these conditions, too, administration of HA interfered with the antibody responses to SRC. Both adherent and nonadherent cells caused inhibition, with this property appearing earlier in adherent than in nonadherent cells. A hypothesis, capable of explaining the observations made in this study and compatible with similar phenomena described in other systems, has been proposed according to which after immunization with HA, SRC are diverted to HA‐stimulated cells which are not equipped to deal with the antigen complex represented by SRC.
Comparison of specificities of humoral and cellular immune responses to haptens
Authors: Alkan Ş. Ş. , El‐Khateeb M. 
Published: February 2007

AbstractIn this study we induced humoral and cellular immunity to three isomers of aminosulfanilic and aminobenzoic acids and compared their respective specificities. These studies were facilitated by using a new method for preferentially inducing a cellular immune response to haptens: the haptens were covalently coupled to mycobacteria and injected into animals in incomplete Freund's adjuvant. Humoral antibody was iduced by coupling the same isomers to bovine serum albumin and injecting them into animals in complete Freund's adjuvant. Both groups of animals were examined for hapten‐specific cellular immunity (migration inhibition factor, delayed skin tests) and for antibody response (passive hemolysin test). The results show that although both cell‐mediated and humoral responses can discriminate the para, meta and ortho isomeric forms of the haptens used, the antibody response demonstrated much less cross‐reactivity. The relevance of this finding to different requirements for B and T cells in antigenic recognition is discussed.
The migration of recirculating autologous and allogeneic lymphocytes through single lymph nodes
Authors: Frost H. , Cahill R. N. P. , Trnka Z. 
Published: February 2007

AbstractUsing cannulated single lymph nodes in sheep the migration of 51 Cr‐labeled autologous and allogeneic recirculating lymphocytes (RL) into efferent lymph was studied after i. v. infusion and infusioninto an afferent lymphatic. The majority of autologous and allogeneic RL appeared in efferent lymph 27–36 h after their infusion i. v. and 6–12 h after intralymphatic infusion. The recovery of i. v. infused allogeneic RL in efferent lymph was only 5–10% that of autologous RL. In contrast, there was no difference in the recovery of autologous and allogeneic RL after infusion into an afferent lymphatic. In primed animals the migration of allogeneic RL through a lymph node was completely inhibited.
Studies on the maturation of thymus stem cells The effects of catecholamines, histamine and peptide hormones on the expression of T cell alloantigens
Authors: Singh Upendra , Owen J. J. T. 
Published: February 2007

AbstractStudies have been performed in order to investigate the effects of catecholamines, histamine, peptide hormones and various other agents known to increase cellular adenosine 3′:5′‐cyclic monophosphate (cAMP) levels, on the expression of Thy‐1 and TL antigens on 14‐day fetal thymic stem cells. It has been shown that the proportions of Thy‐1 and TL positive cells, as detected by dye exclusion cytotoxicity tests, can be significantly increased by some of these agents and that these effects may be inhibited by β adrenergic and H2 antagonists. The value of these tests as a means for studying normal thymic stem cell maturation and for investigating T cell deficiency is discussed.
Cytophilic activity of enzymatically derived fragments of guinea pig IgG2
Authors: Alexander M. D. , Leslie R. G. Q. , Cohen S. 
Published: February 2007

AbstractThe hydrolysis products from short term exposure of guinea pig IgG2 to papain and pepsin have been characterized. Papain hydrolysis liberates 4 types of Fc fragment, only one of which retains both an interchain disulfide bond and an intact CH2 domain, cFc, mol. wt. 56 000. The other three fragments noncovalently linked Fc (nFc) (mol. wt. 56 000), incomplete Fc (iFc) (mol. wt. 39 000) and Fc′ (23 000) represent further degradation products of covalently linked complete Fc (cFc). The cytophilic activities of these fragments as well as F(ab′)2 and pFc′ from pepsin hydrolysis, were studied to determine the domain(s) responsible for binding to homologous peritoneal macrophages. Only the native immunoglobulin and the intact cFc manifested cytophilic activity; in particular pepsin‐derived pFc′ and Fc′ were inactive. Following mild reduction and alkylation, performed to affect only the interchain disulfide bonds, the cytophilic activity of cFc was markedly reduced. The low cytophilic activity in the pFc′ fragment suggests that the CH2 domains play a major part in binding to the macrophage Fc receptor through a site(s) stabilized by the interchain disulfide bonds.
The requirement for tetravalency of soybean agglutinin for induction of mitogenic stimulation of lymphocytes
Authors: Schechter B. , Lis H. , Lotan R. , Novogrodsky A. , Sharon N. 
Published: February 2007

AbstractThe mitogenic activity of soybean agglutinin was found to depend on the presence of lectin aggregates formed in lectin preparations stored in the lyophilized state. Such soybean agglutinin preparations gave maximal stimulation of untreated pig lymph node cells and neuraminidase‐treated mouse spleen cells at relatively high concentrations, ranging from 100 to 2000 μg/ml. After separation into unaggregated (divalent) and polymeric (tetra‐and multivalent) fractions, it was found that the unaggregated lectin did not stimulate the cells, while the tetravalent and multivalent fractions were active and gave maximal stimulation at a concentration of 10 μg/ml. These results suggest that soybean agglutinin must have at least four sugar binding sites in order to be able to stimulate lymphocytes.
H‐2 antigen‐specific cytotoxic T cells induced by concanavalin A: estimation of their relative frequency
Authors: Bevan M. J. , Langman R. E. , Cohn M. 
Published: February 2007

AbstractSpecific and nonspecific lysis of DBA/2 (H‐2d) mastocytoma cells, P815, by concanavalin A (Con A)‐induced cytotoxic T cells was studied. In the assay for nonspecific lysis, phytohemagglutinin (PHA) was present to glue the target and killer cells together. We have presented evidence previously to show that PHA reveals only, and all, cytotoxic T cells. In the assay for specific lysis the only glue present was specific receptors on a fraction of the killer cells and surface antigens of P815. We show that when PHA was present, Con A‐induced cells which were syngeneic, semi‐syngeneic, or allogeneic, lysed P8 15 very efficiently in a 4‐h51Cr release assay. However, only Con A‐induced T cells which were allogeneic and did not carry H‐2d lysed P815 when the assay was carried out in the absence of PHA. In an experiment with two target cells, Con A‐induced B10 (H‐2b) T cells lysed B 10.D2 (H‐2d) targets specifically but did not lyse B10 targets, while Con A‐ induced B10.D2 T cells lysed B10 targets specifically but not B10.D2 targets. Furthermore, Con A‐induced B6 (H‐2b) T cells from normal mice lysed P815 specifically but Con A‐induced B6 T cells from irradiated F1(B6 × BALB/c) (H‐2b/d) mice reconstituted with B6 bone marrow did not lyse P815 specifically. A fraction of Con A‐induced T cells therefore appear to bear specific surface receptors for nonself H‐2 coded structures. We describe conditions of assay and a new method of plotting the results such that nonspecific (PHA‐revealed) and specific (PHA‐independent) cytotoxicity can be quantitatively compared. We conclude that 1–4 % of the total Con A‐induced cytotoxic effector T cells are directed against any particular foreign H‐2 haplotype. This is the first estimate of the relative frequency of antigen‐reactive cytotoxic T cells.
Frequency of precursor cells against the enzyme β‐galactosidase An estimate of the BALB/c strain antibody repertoire
Authors: Köhler G. 
Published: February 2007

AbstractA method has been developed for detecting anti‐β‐galactosidase antibodies after isoelectric focusing in thin layers of polyacrylamide gel. By “staining” with wild‐type enzyme, all antibodies against β‐galactosidase are detected, while a subset of antibodies able to activate a mutant enzyme is detected by staining with that enzyme.Limiting dilutions of β‐galactosidase‐primed or unprimed spleen cells of BALB/c mice were transferred together with antigen into sublethally irra‐diated syngeneic hosts. The limiting role of the precursor B cells has been judged by the analysis of the clonal distribution of galactosidase‐specific antibodies in recipient sera. The frequency of anti‐wild‐type β‐galactosidase precursor cells was one in 0.42 × 106 in the primed and one in 0.93 × 106 in the unprimed spleen. The frequency of precursor cells for antibodies activating the mutant enzyme was one in 1.5 × 1O6 in the primed and one in 4.6 × 106 in the unprimed spleen. Therefore four and five times less anti‐B (mutant) than anti‐B (wild‐type) precursor cells exist in the spleens of primed and unprimed BALB/c mice, respectively.Comparing 51 clones derived from one primed donor mouse, it was possible to demonstrate that at least 43 different mutant‐β‐galactosidase‐activating antibodies can be produced in one mouse. Comparing these 43 clones with 27 clones derived from another donor mouse, only one clone seemed to be common to both mice. From this the repertoire of the BALB/c strain has been estimated to consist of over 1000 different mutant enzyme‐activating antibodies.
Immune complex nephritis in Schistosoma mansoni‐ infected mice
Authors: Natali P. G. , Cioli D. 
Published: February 2007

AbstractSwiss outbred mice infected with 80–100 cercariae of Schistosoma mansoni developed in 60 % of the cases a wide range of glomemlar lesions involving mainly the mesangium. The lesions were associated with the presence of granular deposits of murine immunoglobulins and C3, suggesting an immune complex mechanism. In addition, nephritic glomeruli in about 20 % of the cases could be stained by a specific rabbit antischistosoma serum after removal of excess host immunoglobulins. The presence of circulating immune complexes in the serum of infected animals was suggested by the increased molecular weight of circulating C3. The onset of the immunopathologic lesions appeared to be related to duration, intensity and type of infection. Single‐sex parasite infection, in fact, led to significant reduction of glomerular lesions.
Mechanisms by which hapten conjugates of pneumococcal polysaccharide interfere with the challenge of anti‐hapten memory cells
Authors: Romano T. J. , Lerman S. P. , Thorbecke G. J. 
Published: February 2007

AbstractIncubation of trinitrophenylated hemocyanin (TNP‐KLH)‐primed spleen cells with microgram amounts of 2,4‐dinitrophenyl (DNP) or 2,4,6‐trinitrophenyl (TNP) conjugates of pneumococcal polysaccharide type 3 (SIII) for as little as 5 min at 4 °C results in a specific “block” of the 19 S and 7 S adoptive memory response to TNP‐KLH. This hapten‐SIII‐induced block of anti‐hapten memory B cell responsiveness seems to be an example of specific receptor blockade. The block is specific and can be prevented by simultaneous incubation of the primed cells with hapten‐protein conjugates which presumably compete with the hapten‐polysaccharide for attachment to the B cell surface via anti‐hapten Ig receptors. Removal via capping of these Ig receptors by exposure of TNP‐KLH‐primed memory cells to rabbit anti‐mouse Fab serum for 45 min at 37 °C renders these cells refractory to the blocking effect of hapten‐SIII. Once the hapten‐SIII has attached to the memory cells, these blocked cells can be “rescued” (i.e. returned to a state of responsiveness) by incubating these cells with either mouse anti‐SIII at 37 °C or rabbit anti‐DNP serum at 4 °C. Since a papain digest of the IgG fraction of rabbit anti‐DNP did not rescue the cells while the intact IgG did, a capping off of the TNP‐SIII was proposed as the mechanism for this return to responsiveness of the hitherto blocked cells. A rescue was not seen by treatment of recipient mice with such B cell mitogens as dextran sulfate, endotoxin or purified protein derivative of tuberculin.
Migratory patterns of B lymphocytes. V. Surface Ig and migration properties of density gradient‐separated bursa cells
Authors: Dekruyff R. H. , Onikul S. R. , Thorbecke G. J. 
Published: February 2007

AbstractA study was made of bovine serum albumin density gradient‐separated bursa cells with respect to their distribution on the gradients, % cytotoxicity with anti‐Ig + complement (C) or anti‐μ + C, and localization of fractions in irradiated syngeneic recipients. Layer A showed a higher cytotoxicity with anti‐Ig + C or anti‐μ + C than the others; layer D showed the lowest % cytotoxicity, although a large % of the cells not killed by anti‐Ig were killed by anti‐bursa serum + C. The C + D layers contained a much larger fraction of the Ig+ cells from the bursa in the 1–4‐week‐old than in the 6–12‐week‐old animals, suggesting a relative shift towards lower density of Ig+ bursa cells with age.When [3H]adenosine‐labeled bursa cells from density gradient fractions were transferred, the % injected radioactivity found in recipient spleens was higher for fractions A and B than for fraction C + D. While 50–60 % of the cells from fractions A and B which localized in spleen were found in germinal centers and follicles, a much lower % of the cells from fraction C + D seen in spleen localized in these areas. The results were in agreement with those of previous studies suggesting that it is primarily the Ig‐bearing population among bursa cells which localizes in follicles.
Induction of immune responsiveness in a genetically low‐responsive tumor‐host combination by chemical modification of the immunogen
Authors: Galili Naomi , Naor D. , Åsjö Birgitta , Klein G. 
Published: February 2007

AbstractTrinitrophenylated Moloney virus‐induced YAC cells induced a higher cytotoxic antibody response and better protection against small tumor cell doses in syngeneic, low‐responsive strain A mice than nonmodified YAC cells that had been inactivated by irradiation or mitomycin C treatment. The results indicated that genetically determined low responsiveness to a virally induced antigen can be overcome, at least to some extent, by coupling the immunizing cells to a strong immunogenic hapten.
Immunosuppressive activity of Phaseolus coccineus and Phaseolus vulgaris extracts in mice
Authors: Calderón Raquel A. , Córdoba F. 
Published: February 2007

AbstractLectin mixtures from 10 samples of Phaseolus coccineus and Phaseolus vulgaris beans were used as immunosuppressive agents in the sheep red blood cell (SRBC) antibody response of the mouse. Some bean samples contain lectins capable of inducing several times better suppression of humoral immunity than concanavalin A and phytohemagglutinin tested before in the same immune system.High dilutions of the 10 bean extracts were shown to agglutinate mouse, rabbit and sheep erythrocytes in vitro but the titers and “specificities” did not correlate with the immunosuppressive potency and selectivity displayed by the same extracts in mice.Two immunosuppressive bean extracts, assayed in lymphocyte cultures, were found to stimulate DNA synthesis of murine spleen T cells. This interaction appears to be a necessary step for the reduction of antibody synthesis to SRBC in the whole animal.
A study of the immunoglobulin classes present on the membrane and in the cytoplasm of human tonsil plasma cells
Authors: Ferrarini M. , Viale Giovanna , Risso Angela , Pernis B. 
Published: February 2007

AbstractThe problem of whether immunoglobulin (Ig)‐containing plasma cells expressed membrane Ig has been investigated using cells from human tonsils. In tonsils, IgG‐containing cells are predominant, but a certain number of IgM, IgA and IgD‐containing cells are also present. By using a double staining immunofluorescent technique for the simultaneous detection of membrane and intracytoplasmic Ig, it has been possible to ascertain that the large majority of IgA, IgM and IgD‐containing cells had membrane immunoglobulin (mIg) of a class coincident with that of intracytoplasmic Ig. In addition a noticeable proportion of IgM‐containing cells expressed membrane IgD, thus indicating that a certain number of these cells bore both membrane IgM and IgD. About 60 % of IgG‐containing cells had membrane IgG, while the remaining cells did not express mIg. Furthermore the surface staining of these cells was generally fainter than that of the cells containing other Ig classes.Experiments on the surface light chain type expressed by the single Ig‐containing cells (IgCC) as compared to that found in the cytoplasm have shown that in the large majority of IgCC the light chain type of mIg coincided with that of intracytoplasmic Ig. Discordant light chain types of membrane and cytoplasmic Ig were found on about 12% of IgCC only. These values can be taken as a measure of how many IgCC had passively acquired mIg.
Expression of la determinants on immunocompetent cells
Authors: Hämmerling G. J. , Eichmann K. 
Published: February 2007

AbstractThe expression of Ia (immune response region‐associated) antigens on the surface of lymphocyte subpopulations with defined immunological functions has been investigated by negative selection of subpopulations with anti‐Ia sera and complement. la determinants were found on both unprimed (IgM) and on primed (IgG) antibody‐forming precursor cells. No Ia antigens were detected on the surface of helper T cells. In contrast, suppressor T cells were sensitive to treatment with anti‐Ia sera and complement demonstrating the presence of Ia determinants on this T cell subpopulation.
Antigenic determinants of heavy chain variable regions: immunological typing of the human immunoglobulin VHIII subgroup
Authors: Rivat Liliane , Rivat C. , Lebreton J.‐P. , Ropartz C. 
Published: February 2007

AbstractAn antigenic determinant of the VHIII variable region subgroup was defined by means of a heterologous specific antiserum using a hemagglutination inhibition procedure. The specificity of this antiserum was established in inhibition experiments with proteins either of known primary structure or belonging to a definite VH subgroup.A series of IgG, IgA, IgM and IgD monoclonal proteins was examined for the presence of this VHIII subgroup antigenic determinant. The data showed that 50% of the IgG, 62% of the IgA, 55 % of the IgM and 41% of the IgD were VHIII‐positive, and that certain “blocked” monoclonal immunoglobulins belonged to this subgroup. A preferential association of the VHIII antigenic determinant with the IgG1 and IgG3 subclasses was observed among IgG myeloma proteins while the preferential association was only observed with the JgG1 subclass when anti‐Rh antibodies were studied. The VHIII subgroup exhibited nonallelic behavior.
Role of epitope density in the induction of tolerance and immunity with thymus‐independent antigens. III. Interaction of epitope density and receptor avidity
Authors: Desaymard Catherine , Pearce Barbara , Feldmann Marc 
Published: February 2007

AbstractThe induction of B cell tolerance to 2,4‐dinitrophenyl conjugates of polysaccharide antigens (levan or dextran) was studied in mice primed with keyhole limpet hemocyanin (KLH) or 2,4,6‐trinitrophenylated KLH. The relationship of the epitope density of the tolerogen with avidity of B cell receptors (as judged indirectly by a plaque inhibition assay) was investigated. It was found that high avidity precursors (IgG) were tolerized by antigen of much lower epitope density, and at lower concentration, than were low avidity precursors (especially IgM cells). IgA cells were intermediate in behavior. These results suggest that the epitope density effect acts by ensuring a necessary degree and/or energy of antigen binding.
T cell necessity in the pathogenesis of experimental autoimmune encephalomyelitis in mice
Authors: Bernard C. C. A. , Leydon Jennifer , Mackay I. R. 
Published: February 2007

AbstractCellular transfer of experimental autoimmune encephalomyelitis (EAE) was effected in mice with lymph node and spleen cells from appropriately immunized donors. In contrast to lymphoid cells, immune serum did not transfer this autoimmune disease nor did serum have any facilitating or inhibitory effect on the capacity of lymphoid cells to transfer EAE. Transfer of EAE was effected in normal mice, lightly irradiated (350 rad) and lethally irradiated (850 rad) and bone marrow‐protected mice, but not in mice which had been given 850 rad total‐body irradiation. There was a striking augmentation of severity of transferred EAE in the lightly irradiated recipients, possibly attributable to selective radiosensitivity of suppressor T cells. Cell‐mediated immunity but not circulating antibody to basic protein of myelin was demonstrated in recipients with transferred EAE.The immune lymphoid cells responsible for transfer of EAE were T lymphocytes. Thus transfer was successful after passage of sensitized cells through anti‐immunoglobulin columns and was abrogated following treatment with anti‐Thy‐1 serum and complement.Neonatally thymectomized mice failed to develop either EAE, cell‐mediated immunity or humoral antibody against myelin basic protein (BPM). Inhibition of EAE and immune responsiveness was solely due to the removal of the source of thymus lymphocytes, because reconstitution of neonatally thymectomized mice with T lymphocytes completely restored these functions. It is concluded that T lymphocytes are required for the production and adoptive transfer of EAE, for the development of cell‐mediated immunity to BPM and for the production of antibody to BPM.