bluuebunny/crossref_metadata_2025_split huggingface dataset:
Migration inhibition experiments with mixtures of human peripheral blood lymphocytes and guinea pig peritoneal exudate cells
Authors: Marsman A. J. W. , Van Der Hart Mia , Walig C. , Eijsvoogel V. P. 
Published: February 2007

AbstractMigration inhibition using mixtures of human peripheral blood lymphocytes and non‐sensitized guinea pig peritoneal exudate cells was demonstrable with purified protein derivative of tuberculin (PPD) and Candida albicans extract (CAE) when lymphocytes were obtained from individuals with a delayed type skin reaction to these antigens. No migration inhibition occurred when lymphocytes were used from skin test negative individuals.Furthermore it was found that lymphocytes from some skin test negative persons, which did not induce migration inhibition, showed, however, an increased DNA synthesis when cultured in vitro with PPD. This indicates that a dissociation between the results of migration inhibition, skin test and lymphocyte transformation can occur not only in patients with immune disorders, as has been described by other investigators, but also in healthy individuals.
The enhancement of a primary in vitro anti‐hapten response by carrier priming
Authors: Trowbridge I. S. 
Published: February 2007

AbstractThe primary in vitro antibody response of mouse spleen cell suspensions to the hapten 4‐hydroxy‐3‐iodo‐5‐nitrophenacetyl (NIP) coupled to heterologous red blood cells (RBC) was enhanced by preimmunization of the spleen cell donors with the carrier RBC. The enhancement of the anti‐NIP response by carrier priming was specific and in order to stimulate an in vitro anti‐NIP response, the hapten had to be coupled to the same RBC which was used for priming.The capacity for an enhanced anti‐NIP response developed rapidly after the priming immunization, arising earlier than the anti‐carrier RBC antibody response. There was a close correlation between the priming dose of carrier RBC required to enhance the anti‐NIP response and that required to prime for an enhanced secondary in vitro RBC response. No inhibition of the anti‐NIP response of spleen cell suspensions stimulated by NIP‐SRBC was observed by the addition of excess intact or lysed SRBC.The requirement for a carrier‐specific cell which participates in the anti‐NIP response was demonstrated. The function of this cell in the anti‐NIP response was more resistant to irradiation and treatment with mitomycin C than that of the anti‐NIP precursor cell. From these and other studies in which spleen cell suspensions were treated with high specific activity [3H]d Thd it was concluded that cell division is necessary for the development of the anti‐NIP response, but that the carrier‐specific cell does not have to divide in vitro to execute its role in this response.
The thymus origin of the carrier‐specific cell in an anti‐hapten response in vitro
Authors: Trowbridge I. S. , Anderson H. R. 
Published: February 2007

AbstractThe primary in vitro response of spleen cells to 4‐hydroxy‐5‐iodo‐3‐nitrophenacetyl‐(NIP)‐ hapten was markedly reduced by procedures which depleted the spleen cell population of T cells. One approach was to use adult thymectomized, irradiated, bone marrow restored (TxBM) mice. The anti‐NIP response of spleen cells from carrier (SRBC)‐primed TxBM mice was significantly reduced compared to that of primed sham‐TxBM or primed normal spleen cells, and correlated with a deficient secondary anti‐SRBC response in vitro.Two criteria were used for T cell depletion of TxBM mice: their impaired ability to mount a primary response to SRBC in vivo and the lower proportion of their spleen and lymph node cells susceptible to the cytotoxic action of anti‐Θ serum.Using a second approach, the anti‐NIP response of normal carrier‐primed spleen cells was reduced by pretreatment of the cells with anti‐Θ serum and complement. The anti‐NIP response of anti‐Θ treated cells and cells from TxBM mice was enhanced by the addition of irradiated spleen cells from primed normal mice.The requirement for carrier‐priming to induce a good primary in vitro antihapten response was not abrogated by injecting donor mice with allogeneic lymphoid cells at various times before the preparation of cell cultures.
Mitogen‐induced lymphocyte‐mediated cytotoxicity in vitro: Effect of mitogens selectively activating T or B cells
Authors: Möller G. , Sjöberg O. , Anderson J. 
Published: February 2007

AbstractConcanavalin A (Con A) and phytohemagglutinin (PHA) are selective T cell mitogens, whereas lipopolysaccharide (LPS) and purified protein derivative of tuberculin (PPD) are selective B cell mitogens. Con A and PHA induced mouse lymphocyte‐mediated cytotoxicity in vitro, which was equally expressed on autologous, allogeneic and heterologous target fibroblasts, as measured by thymidine release from prelabeled targets. The dose response curves of Con A‐induced lymphocyte‐mediated cytotoxicity and DNA synthesis were parallel, 5 μg/ml being optimal, both higher and lower concentrations being less effective. Con A pretreated mouse lymphocytes failed to express cytotoxicity even though they were irreversibly activated with regard to DNA synthesis and were morphologically transformed. However, when Con A pretreated lymphocytes were added to target fibroblasts in the presence of soluble Con A, the cytotoxic effect markedly exceeded that induced by Con A in non‐pretreated lymphocytes. It is suggested that cytotoxicity not only requires close contact between target and aggressor lymphocyte, but actual binding of the lymphocyte to the target, in this case effectuated by Con A.Con A and PHA failed to induce lymphocyte‐mediated cytotoxicity in B lymphocytes. LPS and PPD did not induce cytotoxicity in normal or in B lymphccytes. Even LPS or PPD pretreated B lymphocytes failed to exert cytotoxicity when aggregated to the targets by Con A. It is suggested that the lymphocytes responsive to LPS and PPD are not the non‐T cells responsible for cell‐mediated cytotoxicity on antibody‐coated target cells.Con A and PHA, but not LPS and PPD, induced lymphocyte‐mediated cytotoxicity in human lymphocytes on allogeneic and heterologous target fibroblasts. The dose response curves for induction of cytotoxicity and DNA synthesis by Con A were not always identical in this case, cytotoxicity persisting at low Con A concentrations, which failed to activate DNA synthesis.
Lymphocyte activation: Rapid changes in the phospholipid metabolism of plasma membranes during stimulation
Authors: Resch K. , Gelfand E. W. , Hansen Käthe , Ferber E. 
Published: February 2007

AbstractLymph node lymphocytes from normal or BCG‐sensitized rabbits were stimulated by phytohemagglutinin (PHA) or purified protein derivative of tuberculin (PPD). After incubation of intact lymphocytes with [14C]oleate, the cells were disrupted and microsomes (consisting of plasma membrane and endoplasmic reticulum) were isolated. In some experiments the microsomal fraction was separated into plasma membrane and endoplasmic reticulum by dextran gradient centrifugation.After 10 min microsomes from PHA‐stimulated lymphocytes had incorporated 3 times more [14C]oleate into lecithin than microsomes from controls. With PPD as antigen, after 1 h incubation a significant increase in the incorporation of [14C]oleate into microsomal lecithin was detected. The stimulation index with respect to [14C]oleate uptake remained constant in both cases when the lymphocytes were cultured for longer times. Approximately 90 % of the [14C]oleate incorporated into microsomal lecithin was recovered in the plasma membrane which exhibited the highest stimulation. The results are discussed in relation to possible biochemical events underlying the triggering process of lymphocytes.
Plant agglutinins used to distinguish between different classes of mouse lymphocytes
Authors: Schnebli H. P. , Dukor P. 
Published: February 2007

AbstractCortisone‐resistant thymocytes and thoracic duct cells from nu/+ mice and lymph node cells from athymic nu/nu mice were used as highly enriched populations of T and B cells, respectively.The agglutinin from wheat germ agglutinated B cells more strongly (by factors of 5 and 14) than both cortisone resistant thymocytes and thoracic duct cells. Wheat germ agglutinin may thus provide a new B cell‐specific marker.Soy bean agglutinins from two different sources agglutinated B cells and cortisone‐resistant thymus cells equally well, but failed to agglutinate thoracic duct cells. The different behavior of the two T cell preparations is taken as further evidence of the existence of subpopulations of thymus‐derived lymphocytes.
Rosette formation by human T and B lymphocytes
Authors: Brain P. , Marston R. H. 
Published: February 2007

AbstractHuman peripheral lymphocytes, identified as T or B cells with a fluorescent anti‐globulin serum, were studied in two varieties of rosette formation: (1) with sheep red corpuscles, a phenomenon shown by a large proportion of human lymphocytes and totally different from that observed in the mouse; and (2) with human red cells sensitized with incomplete anti‐Rh. Lymphocytes forming sheep cell rosettes were never fluorescent; i.e. they were T cells. 73 % of lymphocytes forming sensitized‐cell rosettes were fluorescent B cells. Horse anti‐human lymphocyte serum inhibits the first but not the second variety of rosette formation.
The avian bursa‐independent humoral immune system: serologic and morphologic studies
Authors: Bryant B. J. , Adler H. E. , Cordy D. R. , Shifrine M. , Damassa A. J. 
Published: February 2007

AbstractChickens injected variously with Mycoplasma gallisepticum organisms or sheep erythrocytes and assayed for specific serum agglutinins were individually evaluated with respect to lymphoid development in spleen, thymus, cecal tonsils, cloaca, and bursa of Fabricius. The examinations were carried out during the period of normal maximal bursa size on chickens which had been chemically bursectomized (CBx) at the 7‐day‐embryo stage and on intact controls. The embryonic genesis of bursal epithelium was completely prevented in 41 of 43 CBx birds. These bursaless birds nonetheless collectively formed agglutinins in 1 of 30 cases at 10 – 12 days after primary stimulation, in 6 of 26 cases at 22 – 23 days after primary stimulation, and in 15 of 32 cases after secondary stimulation. The titers compared favorably with controls. Agglutinin responsive bursaless birds had secondary follicles in spleen and cecal tonsils and an impressive, if variably subnormal, development of lymphoepithelial tissue. By contrast, agglutinin negative bursaless birds lacked germinal centers and had only moderately to sparsely populated lymphoepithelia. This lymphocyte deficit was especially marked in the proctodeal and urodeal roofs and cecal tonsils. Plasmacytes in bursaless birds were rarely found in spleen but were always found in gut lymphoepithelia in numbers correlating with regional lymphoid cell content.
Studies on the effect of a thymic humoral factor on differentiation of thymus‐derived lymphocytes
Authors: Lonai P. , Mogilner B. , Rotter Varda , Trainin N. 
Published: February 2007

AbstractThe effect of a thymic humoral factor (THF) on differentiation of thymus‐derived (T) lymphocytes was studied in various graft‐versus‐host models. It was demonstrated that THF, which is known to be capable of restoring immunocompetence of cells from neonatally thymectomized mice, does not act on lymphoid populations devoid of T cells. Immunologically defective lymphoid cells such as spleen cells obtained from mice treated with anti‐lymphocyte serum could be activated by THF by in vivo or in vitro interaction. These experiments indicate that the target cell acted upon by THF is a T cell with a low level of immunocompetence. It is suggested that THF acts on young T cells and transforms them into mature T cells active in cell‐mediated immune reactions, presumably without substantial multiplication.
Morphological observations on the contact‐induced lysis of target cells
Authors: Koren H. S. , Ax W. , Freund‐Moelbert Elisabeth 
Published: February 2007

AbstractInteractions in tissue culture of sensitized C57BL spleen and DBA/2 mastocytoma cells have been studied by microcinematography, electronmicroscopy and light microscopy. Motile lymphocytes with their characteristic hand mirror shape move on the surface membrane of the target cells, establishing a close contact within a few minutes. As seen by electron microscopy and equidensitometry, the contact between the cells is very firm, leading to damage of the target cell membrane while leaving the effector cell intact. Analysis of time‐lapse cinematography shows that one motile lymphocyte has the capacity to lyse more than one target cell, a phenomenon which may account for the highly efficient surveillance mechanism in vivo. The role of soluble factors and the importance of the lymphocytic uropod in cellular interactions are discussed.
Immunofluorescent detection of surface antigens specific to T and B lymphocytes in the chicken
Authors: Hudson L. , Roitt I. M. 
Published: February 2007

AbstractRabbit antisera specific for chicken T and B cells as judged by surface immunofluorescent staining have been raised. Specificity was established by the staining of thymus and bursal cell suspension and by the effects of thymectomy and bursectomy on the staining of peripheralized lymphocytes. Furthermore, double labeling experiments showed that anti‐T and anti‐B sera reacted with different populations of blood lymphocytes. Comparable numbers of cells in blood and spleen stained for B and light chain determinants. No evidence for “null cells” was obtained. There was little change in the percentage of cells staining in the various lymphoid organs from 4 days to 12 months of age.The thymus contained approximately 7 % B cells, although no T cells were demonstrable in the bursa. One antiserum showed only thymocyte specific antibodies not reacting with peripheral T cells. The specific B and T markers seem to be acquired during differentiation within the appropriate central lymphoid organ. Demonstrable surface immunoglobulins appear later in ontogeny than the B antigens. The majority of cells bearing the B marker in bone marrow were large cells lacking surface light chain determinants.
Studies on sperm antigenicity. I. Delayed hypersensitivity to spermatozoa
Authors: Marcus Z. H. , Soffer Y. , Ben‐David A. , Peleg Sarah , Nebel L. 
Published: February 2007

AbstractDelayed hypersensitivity to human and guinea pig sperm was demonstrated in guinea pigs of the Rockefeller strain by immunization with H37Ra adjuvant. The reaction in vivo was demonstrated by skin testing the animals and in vitro by the capillary method. It was found that the sensitivity is not only directed towards the sensitizing antigen, but also shows cross‐reactivity. Thus, peritoneal exudate cells derived from guinea pigs sensitized to human sperm were inhibited by guinea pig sperm. This cross‐reactivity revealed the possibility of a tissue specific antigen. In addition, supernatants obtained after incubation of the sensitized lymph node cells with the specific antigen were found to be spermatotoxic.
Cytotoxicity of adenovirus‐antibody complexes. Specificity of antibody and virus‐antibody ratio at which cytotoxicity is induced
Authors: Kjellén L. , Ankerst J. 
Published: February 2007

AbstractAdenoviruses aggregate in the presence of type‐specific antibodies against whole virus particles. These aggregates were found to damage human cells in vitro in far higher order of magnitude than virus alone, when virus and type‐specific antibodies were mixed at a certain virus‐antibody ratio. No cytotoxicity occurred when the virus was mixed with type‐specific antibodies in higher or lower dilutions or when the virus was incubated with antisera against another adenovirus serotype. Furthermore, it was found that the cytotoxicity could be prevented by type‐specific anti‐hexon sera and that type‐specific anti‐fiber sera produced cytotoxic aggregates out of subtoxic ones. The presence of the cytotoxic aggregates was demonstrated by electron microscopy and by 51Cr release cytotoxicity tests.
An improved method for the production of antiserum directed against weakly immunogenic tumor antigens
Authors: Kurth R. , Bauer H. 
Published: February 2007

AbstractAn immunization procedure is presented which enhances the immune respons to weakly immunogenic tumor‐specific cell surface antigens by coupling new helper antigens to tumor cells. Mice were immunized with lyophilized tumor cell membranes to which helper antigen was coupled. Only animals which were so primed against the helper antigen as to induce delayed hypersensitivity showed an increased in vitro immune response. This was not found in mice which were not primed or which exhibited immediate hypersensitivity.The possibility is discussed of enhancing immune response by introducing additional helper determinants linked to the original antigens.
The nature of the transforming lymphocyte in chronic lymphocytic leukemia
Authors: Schweitzer Marjan , Melief C. J. M. , Eijsvoogel V. P. 
Published: February 2007

AbstractLymphocyte transformation in vitro was studied with lymphocytes from patients with chronic lymphocytic leukemia (CLL). The responding capacity to phytohemagglutinin (PHA), pokeweed mitogen (PWM) and allogeneic lymphocytes, as well as the stimulating capacity in mixed lymphocyte cultures (MLC), were assessed.Lymphocytes of CLL patients display a depressed and delayed reaction to PHA. In MLC experiments a decreased responding and stimulating capacity could be demonstrated, the latter being reduced to a smaller extent. However, reduced numbers of lymphocytes from normal individuals show a similar reaction pattern with regard to these parameters. By albumin gradient centrifugation the lymphocytes from CLL patients could be separated into a nonresponsive population and other fractions, containing lymphocytes with increased reactivity in comparison with unfractionated cells.It was concluded that the leukemic cells in CLL are completely unresponsive to PHA and PWM and have no MLC activities. All observed in vitro reactivity can be attributed to the small proportion of normal lymphocytes among the leukemic cell population.
The specificity of cellular immunity: studies in guinea pigs using defined tetrapeptides containing p‐azobenzenearsonate‐L‐tyrosine
Authors: Becker M. J. , Levin H. , Sela M. 
Published: February 2007

AbstractThe specificity of the cellular immune response to p‐azobenzenearsonate(ABA)‐L‐Tyr, ABA‐L‐Tyr(L‐Tyr)3, ABA‐L‐Tyr(L‐Ala)3, and (L‐Tyr)3 ABA‐L‐Tyr was investigated. None of these immunogens was able to lead to the formation of anti‐ABA antibodies in guinea pigs as measured by a sensitive hapten‐modified bacteriophage inactivation assay. Using antigen‐induced [2‐14C] thymidine incorporation in lymph node lymphocyte cultures in vitro and delayed hypersensitive skin tests as indicators of cellular immunity, a maximal response was elicited by the homologous immunizing antigen. This indicates that the receptor for the cellular immune response exhibits a high degree of specificity for more than just the ABA or ABA‐Tyr moieties.
Effect in vitro of anti‐immunoglobulin sera on proliferative responses of lymphoid cells to antigen+
Authors: Mond J. , Kaplan R. E. , Thorbecke G. J. 
Published: February 2007

AbstractExperiments were designed to determine the effects, if any, of anti‐immunoglobulin (anti‐Ig) sera on T cell‐dependent proliferative responses in vitro. Using rabbit lymphoid cells there was no inhibition of the proliferative response, but instead, an additive effect of anti‐Ig and either antigen or phytohemagglutinin added together, suggesting stimulation of two different cell populations. Pretreatment of mouse lymphoid cells with anti‐Ig and complement caused a detectable inhibition of the proliferative response, which was probably due to the removal of B cells. Pretreatment with anti‐Θ and complement resulted in a much stronger inhibition.
Properties of educated T cells. The ability of educated T cells to facilitate the immune response to non‐cross‐reacting antigens in vitro
Authors: Waldmann H. , Munro A. , Hunter Phillipa 
Published: February 2007

AbstractThymus‐derived cells educated to either keyhole limpet hemocyanin or fowl IgG can reconstitute the response of T cell‐depleted spleen cell cultures to other non‐cross‐reacting antigens. This response can only be obtained if the initial educating antigen is present in culture.
Affinity of T and B lymphocyte receptors for hapten determinants
Authors: Möller Erna , Bullock W. W. , Mäkelä O. 
Published: February 2007

AbstractThe affinity of anti‐hapten antibodies, produced by single cells, was studied by hapten inhibition of plaque‐forming cells using the local hemolysis in gel assay. The shift in affinity of anti‐hapten antibodies, that occurs with time after immunization, was parallelled by an analogous shift, at the cellular level, with regard to indirect plaque‐forming cells (PFC). Thus, there was a gradual decrease of the hapten concentration which was needed to suppress indirect plaque formation with time after immunization, indicating a gradual increase in the number of high affinity cells. No such shift was observed with cells causing direct plaque formation.Analogous studies were performed with hapten‐specific antigen‐binding cells of T and B origin by using hapten‐inhibition of rosette‐forming cells. Hapten‐specific antigen‐binding cells were present in both cell populations. Lymphocyte binding of haptenated red cells could be specifically inhibited by free hapten. It was found that antigen‐binding B lymphoid cells became gradually more susceptible to hapten inhibition with time after immunization, whereas no such change was observed in antigen‐binding T lymphoid cells. Possible reasons for this discrepancy are discussed, as well as the implications for these findings regarding the specificity and structure of the T cell receptors.
Cellular events in protein tolerant inbred rats. II. Antibody avidity maturation during induction and loss of tolerance
Authors: Bell E. B. 
Published: February 2007

AbstractComplete and partial states of tolerance were induced in (AS2 x AS)F1 hybrid rats after single or repeated injections of high, medium and low doses of fluid HSA (100 mg to 10 μg). Changes in antibody avidity, following challenge with HSA plus adjuvant, were used to detect those affinity subclasses of HSA‐specific cells which were not eliminated by tolerogenic antigen.Rats undergoing prolonged low dose treatments of fluid HSA induced an appreciable quantity of high avidity antibody before challenge. The avidity decreased significantly following challenge, indicating a progressive loss of high affinity cells, but only after the synthesis of antibody. Rats made partially tolerant against large and medium doses of fluid HSA when challenged, synthesized antibody which failed to mature to a high level, indicating again that high affinity cells were among the first to be deleted. The higher affinity cells in primed rats (including partially unresponsive rats) were the first to disappear during the memory response which was also triggered by fluid HSA. It is proposed that protein antigens induce a state of tolerance by eliminating B cells, but only after driving them through a stage of antibody synthesis.Avidity of antibody was measured following restoration of HSA responsiveness. Antibody failed to mature to a high level in previously tolerant rats that were allowed to recover naturally (stem cell replacement) or were given normal thoracic duct lymphocytes after the tolerance inducing treatment.