bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased reactivity of responding cells in the mixed lymphocyte reaction by a thymic humoral factor
Authors: Umiel Tehila , Trainin N. 
Published: February 2007

AbstractA thymic humoral factor (THF) induces competence in a certain sector of the lymphoid cell population. The target cell for THF activity was studied using the one‐way mixed lymphocyte culture (MLC). Cells from various lymphoid tissues (responding cells) were preincubated in THF for 1 hour and then mixed with mitomycin‐C‐treated cells (stimulating cells). The results obtained indicate that THF increases MLC competence of lymphocytes from spleen and thymus origin of intact mice and that of spleen of thymus‐deprived mice. In contrast, no enhancing effect in the MLC response by THF could be observed when bone marrow‐derived spleen cells, cortisone‐resistant thymocytes or lymph node cells were used as responding cells. These results confirm our hypothesis that THF leads to differentiation of young thymus‐derived (T) cells, promoting them to maturation and thus to the acquisition of full immune competence.
Radioactive antigen suicide of an anti‐DNP (2,4‐dinitrophenyl) clone. II. Follow‐up of clones relatively resistant to radioactive antigen suicide when initially selected
Authors: Willcox H. N. A. , McMichael A. J. 
Published: February 2007

AbstractAfter suicide of the anti‐dinitrophenyl (DNP) clone E21 in a previous experiment (Eur. J. Immunol. 1975. 5: 58) several new clones (S clones) appeared promptly in the recipients. There was compelling evidence that they were then resistant to suicide, relative to E21. We now report further studies on these S clones and their antibodies.The antibodies of half of the S clones had affinities ten to one hundred times higher than E21 (3 × 10−7 M); none was lower. The four tested were also able to bind DNP on the particular conjugate used for the suicide procedure.Three of the S clones were serially propagated; they showed a very great capacity for proliferation, transferring into 510, 85 and 110 recipients each. When their cells were tested at subsequent passages, they recovered early after partial inhibition by radioactive antigen. Two S clones may still have been somewhat refractory to suicide but, probably in all three, rapid proliferation was largely responsible for the recovery of the few cells escaping suicide, and helped them to appear suicide resistant.
Cell‐mediated immunity to Moloney sarcoma virus in mice. II. Analysis of antigenic specificities involved in T lymphocyte‐mediated in vivo rejection of murine sarcoma virus‐induced tumors
Authors: Gorczynski R. M. , Knight R. A. 
Published: February 2007

AbstractSublethally irradiated BALB/c mice innoculated with Moloney sarcoma virus (MSV‐M) develop progressively growing tumors and die within 30 days of virus innoculation. These animals can be protected from tumor progression (and death) by innoculation of small numbers of MSV‐immune T lymphocytes from MSV‐M innoculated (but unirradiated) animals. T lymphocytes in these donor animals have been shown to express immunity to a variety of viral and virallyinduced antigens. We have investigated whether immunity to any one of these antigens was critically important in leading to protection of the irradiated animals by sesitizing normal T lymphocytes in vitro to different viral antigens and examining the ability of these sensitized cells to protect the irradiated recipients. Data is presented to show that cells sensitized in vitro to MSV‐transformed fibroblasts, and to purified antigens with group specificity, but not to viral envelope antigens, or whole virus, are capable of protecting the irradiated MSV innoculated animals.
Isolation and properties of a 7 S rat immunoglobulin different from IgG
Authors: Binaghi R. A. , Boussac‐Aron Yolande 
Published: February 2007

AbstractA 7 S rat immunoglobulin, of rapid electrophoretic mobility, was characterized and isolated from normal or hyperimmune rat serum and was designated “IgR”. This immunoglobulin belongs to a class different from IgG and was originally described as IgA.IgR has a molecular weight of 160 000, is present in the serum and milk as a monomer and is readily absorbed by the intestine of suckling rats. In hyperimmunized animals, about 20 % of the antibodies were of the IgR class. IgR is devoid of anaphylactic capacity and no homologies could be established between it and immunoglobulins of other animal species.
Cell surface immunoglobulin. XII. Localization of immunoglobulin on murine lymphocytes by scanning immunoelectronmicroscopy
Authors: Lipscomb Mary F. , Holmes Kathryn V. , Vitetta Ellen S. , Hämmerling U. , Uhr J. W. 
Published: February 2007

AbstractThe localization of immunoglobulin (Ig) on the surface of murine splenic lymphocytes has been studied with the scanning electron microscope (SEM), using a rabbit F(ab)2 hybrid antibody directed against mouse Ig and tobacco mosaic virus (TMV) with TMV as a morphological marker. 35 % of spleen cells and 3 % of thymus cells were labeled by this method. Labeled cells were usually small lymphocytes with moderate numbers of microvilli. The Ig molecules were randomly distributed on the lymphocyte surface, appearing on microvilli as well as on the smooth surface of the cell.
Human lymphoblast cell lines: Antibody‐dependent cytotoxicity
Authors: Lefebre J.‐C. , Petitprez A. , Juy D. , Bona C. 
Published: February 2007

AbstractFive cell lines were isolated after prolonged culture of human buffy coat leukocytes. The cells consisted for the most part of lymphoblasts morphologically similar to those produced by in vivo or in vitro stimulation of small lymphocytes by antigens or mitogens. One of the lines possessed virus‐like particles of the Epstein‐Barr type. All the established lines were capable of mediating antibody‐dependent cytotoxicity (LADC) quantitatively at a level not significantly different from that mediated by freshly isolated, normal human peripheral blood lymphocytes (PBL). The LADC of the lymphoblasts was inhibited by all the human IgG subclasses tested (IgG1, IgG2, IgG3, IgG4) as was the LADC of PBL. It is concluded that, at least so far, the lymphoblasts have retained the properties of the lymphocytes from which they were originally derived as regards their ability to mediate LADC.
Recruitment of effector lymphocytes by initiator lymphocytes: role of a trypsin‐sensitive membrane component
Authors: Livnat S , Cohen I. R. 
Published: February 2007

AbstractIn earlier studies we found that initiator T lymphocytes sensitized in vitro against fibroblasts were able to recruit immunospecific effector T lymphocytes in vivo in syngeneic mice. In the present study, to investigate the possible function in effector cell recruitmentof sensitizing antigens passively adsorbed onto the initiator cell membrane, we treated the initiator lymphocytes with trypsin. We found that trypsin inhibited recruitment. However, the initiator cells spontaneously recovered their recruiting ability after incubation in vitro for 4 h in the absence of contact with sensitizing antigens. Recovery could be blocked by cycloheximide. Hence, it appears that recruitment depends on the intrinsic metabolic function of the initiator lymphocytes and is not due merely to passively‐adsorbed antigen carried over into the recipient mouse.
X‐ray enhancement of splenic rosette‐forming cells in nonimmune mice
Authors: Watanabe S. , Kajiwara H. , Minowada J. , Yamamura Y. 
Published: February 2007

AbstractThe formation of rosettes between spleen cells from nonimmune mice and sheep red blood cells (SRBC) has been investigated. The number of splenic rosette‐forming cells (RFC) in the intact spleen was very low but greatly increased after sublethal whole body x‐irradiation. These cells were inhibited by pretreatment of the cells with AKR anti‐C3 H‐Θ antigen antiserum, in the presence of fresh guinea pig serum, but not with rabbit anti‐mouse immunoglobulin antiserum. The splenic RFC also increased after cortisone acetate administration into mice. These results suggest that the RFC are a T cell subpopulation having x‐ray resistant and cortisone‐insensitive characteristics. The x‐irradiation of mice in vivo selectively increased the number of splenic RFC in consequence of reduction in the number of cells having non‐T cell characteristics. These RFC are presumably antigen‐specific sheep red blood cell rosettes, a quite different situation as in the case of human T lymphocyte rosette formation.
Role of epitope density in the induction of immunity and tolerance with thymus‐independent antigens. I. Studies with 2,4‐dinitrophenyl conjugates in vitro
Authors: Desaymard Catherine , Feldmann Marc 
Published: February 2007

AbstractThe effect of different degrees of conjugation of levan, dextran, pneumococcal polysaccharide SIII and the copolymer of D‐glutamic acid and D‐lysine with the 2,4‐dinitrophenyl determinant (DNP) on the immunogenic and tolerogenic capacity of its haptenic conjugates was investigated in vitro. A strikingly uniform effect of hapten conjugation was observed despite the marked difference in the mol. wt. and structure (branched or linear) of the carrier molecules. Regarding the anti‐DNP response, low density conjugates were immunogenic but not tolerogenic (even at high doses), higher conjugates were both, depending on concentration, while very high density conjugates were only tolerogenic. These results confirm and extend earlier findings made with DNP conjugates of polymeric flagellin and indicate the probable generality of this principle. Together with parallel in vivo studies (Eur. J. Immunol. 1975. 5: 541), they reaffirm the importance of epitope density in the discrimination between immunity and tolerance.
The effect of the thymus‐independent antigens, collagen and synthetic collagen‐like polypeptide, on the requirement of cell cooperation in the immune response to thymusdependent antigens
Authors: Mozes Edna , Schmitt‐Verhulst Anne‐Marie , Fuchs Sara 
Published: February 2007

AbstractThe effect of thymus‐independent antigens on the need for cell cooperation in the immune response to thymus‐dependent antigens was investigated. Irradiated recipient mice transplanted with either bone marrow cells or a mixture of bone marrow and thymus cells, were immunized with the thymus‐independent antigen (Pro‐Gly‐Pro)n covalently conjugated to the thymus‐dependent ovalbumin, or with a mixture of (Pro‐Gly‐Pro)n and ovalbumin. In both cases an effective response towards ovalbumin was observed in the absence of thymus cells as was found for the thymus‐independent (Pro‐Gly‐Pro)n. The same effect on ovalbumin was demonstrated when a mixture of the thymus‐independent collagen and ovalbumin was used for immunization. On the other hand, when irradiated reconstituted mice were immunized with a mixture of ovalbumin and the thymus‐dependent gelatin, which is the denatured product of collagen, cell‐to‐cell cooperation was required for an immune response to both immunogens.The effect of (Pro‐Gly‐Pro)n and collagen on the response to the thymus‐dependent ovalbumin in vivo was observed in in vitro experiments using sheep red blood cells (SRBC) as the immunogen as well. In the presence of reduced and carboxymethylated (RCM) Ascaris collagen and (Pro‐Gly‐Pro)n, nude spleen cells could produce significant numbers of plaque‐forming cells towards SRBC. Thus, (Pro‐Gly‐Pro)n and collagen can deliver the signal required to stimulate B cells to produce antibody towards thymus‐dependent antigens in the absence of T cells.In contrast to the results with (Pro‐Gly‐Pro)n and collagen, the thymus‐independent synthetic polypeptide poly (DTyr, DGlu)‐poly(DPro)‐‐poly(DLys) did not affect the requirement for cell cooperation of the thymus‐dependent immunogens, ovalbumin and SRBC. It thus appears that the ability to substitute for T cells for antibody production towards thymus‐dependent immunogens is not a general characteristic of thymus‐independent antigens.
Studies on sperm antigenicity. IV. Lymphocyte cytotoxicity in cell‐mediated response to homologous spermatozoa
Authors: Toder V. , Marcus Z. H. , Nebel L. 
Published: February 2007

AbstractIn the presence of specific antigen, lymph node cells from Rockefeller strain guinea pigs with delayed hypersensitivity to homologous spermatozoal antigen produced progressive destruction of L929 cell monolayers. This effect was measured by counting surviving target cells removed from Leighton tubes by trypsin treatment as well as by standard cell counts in microplates. The cytotoxic effect was immunologically specific since neither sperm‐sensitized lymphocytes in presence of unspecific antigen nor normal lymph node cells with guinea pig sperm, induced target cell destruction. The effect required an antigen concentration equal to, or greater than, 70 μg protein/ml. A ratio of 100 : 1 of sensitized lymphoid cells to target cell was found to be optimal. L‐cell lysis could be demonstrated at day 14 and reached its peak on day 21 after immunization. A high level of correlation between lymphocyte cytotoxicity and macrophage migration inhibition was found.The role of lymphocyte cytotoxicity in cell‐mediated immunity to spermatozoa is discussed as one of the possible mechanisms leading to destructive changes in the testes.
Enrichment of effector T lymphocytes specific to H‐2 antigens by elution from allogeneic target cells and characterization of the eluted lymphocyte population
Authors: Brondz B. D. , Egorova S. G. , Kotomina I. F. 
Published: February 2007

AbstractThe technique of elution by pronase of murine immune lymph node cells adherent to relevant allogeneic target cells has been developed for enrichment of effector T cell population. A fraction of killer cells has been obtained possessing cytotoxic activity which exceeds that of the initial immune lymphocyte population by a factor of 6–8 as judged by a number of lymphocytes required for 50% cytotoxic effect (CE). The gain in CE is fairly reproducible in different H‐2 systems and under various lymphocyte‐target incubation conditions. It appears to be due to the quantitative enrichment of the population in cells bearing receptors to the particular H‐2 antigens and giving rise to specific CE rather than to an increase in cytotoxic activity per cell resulting from treatment with the target monolayer and pronase. The eluted killer cell fraction is characterized by a twofold increase in percentage of cells killed by anti‐Θ antibody, a 4–5‐fold increase in the number of DNA‐synthesizing cells and by an increase in medium and large lymphocyte content. A further enrichment in effector lymphocytes is reached by depletion of B cells at the expense of their receptors to Fc fragment of Ig. Macrophage monolayer fixed by glutaraldehyde lost its capacity to absorb effector lymphocytes. The implications of the data obtained for further studies on cell‐mediated immunity are discussed.
Antibody synthesis by chicken spleen cells in vitro. I. Requirements of B cells at various stages after immunization for T cells, macrophages and antigen
Authors: Evans G. , Ivanyi J. 
Published: February 2007

AbstractThe requirements for T cells, macrophages and antigen during the induction of in vitro antibody responses were ascertained with chicken spleen cells obtained at various times after immunization with sheep red blood cells (SRBC). The IgM plaque‐forming cell (PFC) response was T cell independent exclusively in cultures initiated 3 days after priming, but macrophage dependent at all time intervals tested. In cultures started 4 to 10 days after priming the IgG response was both T cell and macrophage independent and PFC numbers remained at a high plateau level throughout the culture period. In contrast, IgG responses initiated more than 15 days after priming showed a reversal to complete T cell and macrophage dependence and were characterized by a sharp increase in PFC numbers between days 2 and 4 of culture. Formaldehyde‐fixed SRBC were immunogenic for IgG PFC 4 to 10 days after priming but failed to stimulate later IgG memory and all IgM responses. Contrasting antigen dose requirements for IgM and IgG responses were found in cultures initiated at various periods after priming.The results suggest that direct contact with fixed antigen was sufficient to maintain IgG antibody synthesizing PFC in vitro, while native antigen and cell co‐operation were required for late secondary IgG and all IgM responses. These results are interpreted in terms of separate pathways of differentiation for IgM and IgG antibody‐producing cells. A distinct 3rd day stage of T cell‐independent but macrophage‐dependent responsiveness for both classes of antibody was also defined.
The dominant role of la antibodies in the passive enhancement of H‐2 incompatible skin grafts
Authors: Staines N. A. , Guy K. , Davies D. A. L. 
Published: February 2007

AbstractThe ability of H‐2 antisera and their constituent K and la antibodies to enhance the survival of skin allografts was investigated. Ia sera were prepared from H‐2 alloantisera by exhaustive absorption with donor‐strain RBC and the absorbed K antibodies were also recovered by acid elution of the RBC. The removal of conventional K/D antibody in no way diminished the activity of enhancing sera over wide dose ranges in two different incompatibility systems. The recovered K/D antibodies in the doses used had at best a trivial enhancing effect. The dominant role of Ia antibodies in enhancement was confirmed by showing significant prolongation of graft survival in third‐party systems where the sera covered only some of the Ia antigens in incompatibilities involving K,D and Ia differences and in homologous systems using Ia sera fractionated into their constituent mono‐specificities. It is concluded that enhancement is a function of antibodies directed against Ia antigens (I region products) and that antibody against conventional histocompatibility antigens such as H‐2.K, D, and by homology HL‐A and Ag‐B has only a minor role in passive enhancement.
Macrophage inhibiting activity in serum and central lymph of Listeria‐immune mice
Authors: Kaufmann S. , Weber L. , Hahn H. 
Published: February 2007

AbstractSerum and central lymph from mice immunized with live Listeria monocytogenes six days previously and boostered four hours before collection exerted significant inhibition of macrophage migration in vitro. It is concluded that lymphokines or lymphokine‐like products of the cellular immune reaction are released in vivo and are possibly instrumental in the generation of acquired cellular antibacterial immunity.
Ir gene control of carrier recognition. I. Immunogenicity of bovine insulin derivatives
Authors: Keck K. 
Published: February 2007

Abstract2,4‐Dinitrophenyl‐lysin B29 ‐bovine insulin was used as immunogen to investigate the carrier function of insulin in the induction of immune response. Experiments with backcross mice suggest that this is controlled by autosomal Ir genes. The response pattern shown by congenic mice demonstrate the linkage of these genes to the H‐2 complex. With a standard dose of 20 μg per mouse, strains with the H‐2 haplotypes d,b,v respond to this carrier. All other strains tested, with the H‐2 haplotypes a,k,u,r,s,q, are nonresponders.The two Ir genes, Ir‐insulinBov (H‐2d) and Ir‐insulinBov (H‐2b), which are associated with H‐2d and H‐2b respectively, can be distinguished from one another on a functional basis. Only H‐2d mice respond to an appreciable extent when B. pertussis organisms are the adjuvant. With complete Freund's adjuvant, H‐2d and H‐2b mice give high antibody titers, but with low doses of antigen only H‐2d mice respond. In contrast to H‐2d mice, H‐2b mice do not respond to trifluoresceinthiocarbamyl insulin, suggesting that the dimeric insulin might be the immunogenic form in these mice. Furthermore, as has been shown earlier (Nature, 1975. 254: 78.), the A‐chain loop is needed as a carrier determinant only in H‐2b mice.Experiments with recombinant strains localize Ir‐insulinBov (H‐2b) to the left of Ir‐1B, probably in Ir‐1A.H‐2k mice are strict nonresponders, even when other proteins such as bovine IgG, methylated bovine serum albumin or rabbit IgG are provided as carriers complexed with insulin. However, if proinsulin is used as the antigen, anti‐insulin antibody can easily be raised in these strains.
The frequency of effector cells in populations containing cytotoxic T lymphocytes
Authors: Berke G. , Gabison D. , Feldman M. 
Published: February 2007

AbstractA new approach for the direct enumeration of effector cells in populations containing cytotoxic T lymphocytes is described. Stable lymphocyte‐target cell conjugates are formed during centrigugation at room temperature of mixtures containg cytotoxic lymphocytes and target tumor cells. Various types of lymphocyte‐target cell conjugates can be formed, the composition of the conjugate being dependent upon the ratio of lymphocytes to target cells during the conjugation process. The number of conjugates formed is highest at equal lymphocyte and target cell concentrations. At least 35% of the BALB/c anti‐EL4 peritoneal exudate lymphoid cells can conjugate to target cells and the majority of the conjugated lymphocytes are also killer cells. The variation in cytolytic activity of lymphoid cells with time following immunization and the differences in the lytic activity of immune lymphoid cells from various lymphoid organs are due to differences in the actual number of effector cells capable of conjugating with target cells.
The modulation of microprojections on the lymphocyte membrane and the redistribution of membrane‐bound ligands, a correlation
Authors: Loor F. , Hägg Lena‐Britt 
Published: February 2007

AbstractImmunofluorescence microscopy allows one to detect microprojections on the lymphocyte surface and to follow their modulation by various environmental conditions. Both T and B cells express villi similarly. Among other factors, the expression of villi is decreased after cell chilling, is enhanced in the presence of metabolic inhibitor, is decreased in the presence of an agent affecting microfilament integrity, is relatively insensitive to agents affecting microtubule integrity, is sensitive to the pH, is inhibited by high does of lectins and is dependent on the lack of detectable crosslinking of membrane antigens by the ligand.Striking similarities suggest a correlation between the ring → spots → cap transition phenomenon and the villi dynamics on the cell surface.The possible function of lymphocyte villi is discussed.
A characterization of human B and T lymphocytes by their lactate dehydrogenase isoenzyme pattern
Authors: Plum J. , Ringoir S. 
Published: February 2007

AbstractHuman lymphocytes have been separated by two different techniques: the rosette sedimentation technique and the nylon wool column filtration method. The unseparated lymphocytes and each B and T fraction obtained, were examined according to their capacity to form E and erythrocyte antibody‐complement complex (EAC) rosettes. The lactate dehydrogenase (LDH) isoenzyme pattern was studied on each cell population after agar gel electrophoresis.The T lymphocytes showed a significantly higher activity in the LDH‐1 band compared to the B lymphocytes. Previous contradictory reports on the LDH isoenzyme pattern of unseparated lymphocytes and the characterstic decrease of the LDH‐1 band observed in chronic lymphocytic leukemia cells are discussed.A possible application of the isoenzyme distribution in B and T cells, i.e. a criterion for characterization of human B and T lymphocytes, is proposed.