bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lyt phenotypes of primary cytotoxic T cells generated across the A and E region of the H‐2 complex
Authors: Vidovic Damir , Juretic Antonio , Nagy Zoltan A. , Klein Jan 
Published: February 2007

AbstractSix different cell‐mediated lympholysis (CML) combinations were established, four of which generated effector cells against the I‐E, and two against the I‐A molecule. The cell surface phenotype of effector cells was then determined by depletion of cytotoxic T lymphocyte (CTL) activity with antisera and rabbit complement (C) treatment. Both types of effector cells were completely eliminated by treatment with anti‐Thy‐1.2 antiserum plus C. Anti‐Lyt‐1.2 and C depleted anti‐A and anti‐E killer activity but did not eliminate CTL generated across a whole H‐2 difference. One out of three different batches of anti‐Lyt‐2.2 antiserum did not deplete anti‐A killer activity, while it efficiently eliminated CTL generated across the E region or whole H‐2 difference. However, two batches of anti‐Lyt‐2.2 antiserum depleted also anti‐A CTL activity. A quantitative difference between anti‐A and anti‐E CTL in terms of Lyt‐2 expression was demonstrated by significant differences in recovery of killer activity, after treatment of these two types of CTL with a wide concentration range of the same anti‐Lyt‐2.2 antiserum and C. Thus it is concluded that anti‐A killer cells have the cell surface phenotype of Thy‐1+, Lyt‐1, Lyt‐2↑, whereas anti‐E CTL are Thy‐1+, Lyt‐1↑, Lyt‐2←. The data are discussed in the context of a possible association of Lyt phenotypes of T cells with the type of MHC antigens they recognize.
The identification of specific antigens in circulating immune complexes by an enzyme‐linked immunosorbent assay: detection of bovine x‐casein IgG complexes in human sera
Authors: Cunningham‐Rundles Charlotte 
Published: February 2007

AbstractCirculating immune complexes have been implicated in the development of tissue injury in many chronic disease states, but in most instances the inciting antigens have not been identified. This report describes the development of a sensitive enzymelinked immunosorbent assay which can be used to screen rapidly and simultaneously the immune complexes of numerous sera for the presence of a suspected antigen. The prototype antigen sought here was x‐casein, a frequent participant in immune complex formation in IgA deficiency and in atopic diseases. The enzyme‐antibody conjugate described here can detect as little as 0.11 ng/ml of x‐casein for immune complexes formed in vivo or in vitro, one can distinguish circulating complexes containing casein from complexes not containing this antigen. Using this reagent, a major antigen in the immune complexes of hypogamma‐globulinemic patients treated with intravenous γ‐globulin was unexpectedly identified as x‐casein. This method of specific immune complex analysis is suggested as a practical and effective approach to the elucidation of the antigenic constituents of immune complexes found in many diseases.
Regulation of ongoing IgE antibody responses with minute doses of antigen
Authors: Jarrett Ellen E. E. , Hall Elizabeth 
Published: February 2007

AbstractRepeated challenge of egg albumin‐immunized Hooded Lister rats with a tiny amount of antigen presents a stimulus not only to effector cells for an IgE response but also to a related class‐selective suppressive mechanism which eventually becomes predominant. The results obtained suggest that IgE responsiveness is abrogated by exposure to an antigen dose which is several orders of magnitude lower than required for the regulation of antibody of other classes.
Genetic and antigenic requirements for induction of T helper cells for anti‐Sendai virus‐specific antibody production
Authors: Ertl Hildegund Christa Johanna 
Published: February 2007

AbstractT helper cells for the promotion of Sendai virus‐specific antibody production were generated in vitro. They could be stimulated by infectious, UV light‐inactivated or fusion‐negative Sendai virus, which had to be presented by adherent cells. Induction of T helper cells was virus‐specific and required H‐2 IA region compatibility between T cells and antigen‐presenting cells. Delivery of help to B lymphocytes was neither virus‐specific nor H‐2‐restricted.
Functional activities of antibodies against brain‐associated T cell antigens I. Induction of T cell proliferation
Authors: Jones Barry , Janeway Charles A. 
Published: February 2007

AbstractRabbit anti‐mouse brain antiserum mediated an in vitro cooperative interaction between Ig‐anti‐Ig column‐purified Lyt‐1+, Lyt‐2− T cells and spleen B cells. DNA synthesis in the B cells was inhibited with mitomycin C, and the T cell proliferative response was measured by [3H]thymidine incorporation after 24 h of culture. The T‐B cell interaction was genetically unrestricted, and the accessory function of the B cell was engaged via interaction with the Fc portion of the T cell‐bound anti‐mouse brain antibody since the F(ab′)2 fragment was inactive. The rabbit anti‐mouse brain antiserum appears to recognize a unique antigenic determinant in the T cell membrane which triggers proliferation. Although brain‐absorbed, rabbit anti‐mouse thymocyte antiserum contained antibodies which bound to the T cell surface, it was incapable of inducing T cell proliferation. Furthermore, the Thy‐1 molecule itself did not appear to be involved because allo‐ and xenoantisera against the allelic determinants were inactive, and the capping of Thy‐1.2 from the T cell surface did not prevent the binding of the mitogenic component in rabbit anti‐mouse brain antiserum.The T cell reaction to anti‐brain antiserum is unlike the antigen‐specific T cell response in being genetically unrestricted. It is possible that the antibody operates via the perturbation of a T cell determinant involved in the binding of T cell growth factors, and/or reception of B cell feedback signals.
Involvement of the spleen in the control of the immunogenic and phagocytic function of thioglycollate‐induced macrophages
Authors: Ron Yacov , De Baetselier Patrick , Feldman Michael , Segal Shraga 
Published: February 2007

AbstractThe immunogenic capacity of thioglycollate‐induced peritoneal macrophages of adult splenectomized animals was compared to that of macrophages of sham‐operated controls. Macrophages from splenectomized animals were found to be impaired in their function as antigen‐presenting cells, both in the education of virgin initiator T lymphocytes and in the stimulation of antigen‐specific T memory cells. Macrophages from splenectomized animals were also severely impaired in their phagocytic capacity, as assessed in an opsonin‐dependent bacterial phagocytosis assay. However, they were not impaired in their ability to pynocytose soluble keyhole limpet hemocyanin. These results indicate that the spleen may play a dicisive role in controlling the differentiation of peritoneal macrophages.
Cyclosporin A mediates immunosuppression of primary cytotoxic T cell responses by impairing the release of interleukin 1 and interleukin 2
Authors: Bunjes Donald , Hardt Conny , Röllinghoff Martin , Wagner Hermann 
Published: February 2007

AbstractThe site of action of the immunosuppressive drug cyclosporin A in in vitro cytotoxic allograft responses has been localized. General cytotoxic effects of the drug on proliferating T cells became apparent at concentrations of 500–1000 ng/ml, while selective effects were observed at concentrations of 10–100 ng/ml. The selective effects included a blockade of interleukin 2 release from activated T helper cells on the one hand and inhibition of interleukin 1 release from splenic adherent cells on the other. While cyclosporin A did not interfere with the intracellular events required for the activation and subsequent clonal expansion of alloreactive T cells, the lack of interleukin 1 and interleukin 2 induced by cyclosporin A results in an inability of T responder cells to mount cytotoxic allograft responses in vitro.
Dynamics of antibody‐ and lectin‐mediated endocytosis of hapten‐containing liposomes by murine macrophages
Authors: Geiger Benjamin , Gitler Carlos , Calef Edna , Arnon Ruth 
Published: February 2007

AbstractThe uptake by murine macrophages of liposomes, exhibiting one of a variety of haptenic groups on their surfaces, was greatly enhanced by the addition of an intact antibody or a lectin specific for the incorporated hapten. The uptake of untreated liposomes was slow and linear over long periods, whereas upon addition of the antibody or lectin, over 30‐fold increase in the maximal rate of uptake was observed. The process reached a plateau after 90–120 min. The interaction of the antibody‐ or lectintreated liposome with the macrophages apparently resulted in an active endocytosis of the vesicles. As observed by fluorescence microscopy, the distribution of a water‐soluble fluorescent, intraliposomal marker had a granular intracellular pattern in treated cells. The uptake was sensitive to azide and the liposome constituents could not be detected at the cell surface. The size of the liposomes as well as the state of stimulation of the macrophages (thioglycollate stimulated vs. normal) did not seem to have a major effect on the phagocytic process. The time required to reach the plateau in uptake was independent of liposome composition or antibody concentration and is, apparently, an intrinsic property of the cells. The implication of this phenomenon on the dynamics of the relevant macrophage receptors is discussed.
Induction of anamnestic T cell proliferation by antigen‐pulsed, bone marrow‐derived macrophages
Authors: Reske‐Kunz Angelika B. , Spaeth Eberhard , Reske Konrad , Lohmann‐Matthes Marie‐Luise , Rüde Erwin 
Published: February 2007

AbstractBone marrow‐derived macrophages (BMMϕ) were grown in a liquid culture system in the presence of L cell‐conditioned medium as a source of colony‐stimulating factor. After a 4‐h pulse with antigen, cultured irradiated BMMϕ were capable of presenting the antigen to primed T cells as assessed in a T cell proliferation assay. Proliferation was optimal when BMMϕ were used between days 5 and 8 of bone marrow cell culture. T cells of Lytl and Lyt123 phenotype had to be present at the start of the culture period to yield an optimal response. Conventional antisera and monoclonal antibodies directed against the H‐2 I region and the I‐A subregion, respectively, proved inhibitory in this system. Cultured BMMϕ from low‐responder strains failed to present antigens under immune response gene control in a form that was immunogenic to T lymphocytes. Cultured BMMϕ might thus serve as a source of antigen‐presenting cells in the study of cell‐cell interaction and immune response gene regulatory mechanisms.
Phagocytosis and degradation of DNA‐anti‐DNA complexes by human phagocytes. II. Influence of the size of the complexes
Authors: Lamers Marinus C. , de Groot Elisabeth R. , Roos Dirk 
Published: February 2007

AbstractThe influence was studied of the size of DNA‐anti‐DNA complexes on their capacity to induce phagocytosis and degradation by monocytes and neutrophils from human blood. An estimate of the size of the complexes was obtained by precipitation analysis, sucrose‐gradient velocity sedimentation and filtration over Nucleopore filters. The results show that only those complexes are processed that precipitate in 15 min at 3000 × g. These complexes have an S value of more than 25 000 and a diameter of more than 0.4 μm. Likewise, tetanus‐anti‐tetanus complexes also had to be precipitable in 15 min at 3000 × g to be processed by the phagocytes.
Clearance of sensitized erythrocytes in NZB/NZW mice Effects of castration and sex hormone treatment
Authors: Shear Hannah Lustig , Roubinian Jirayr R. , Gil Paul , Talal Norman 
Published: February 2007

AbstractThe clearance of particulate immune complexes consisting of erythrocytes sensitized with IgG or complement was investigated in (NZB × NZW)F1 (B/W) mice. Treatment of castrated B/W mice with androgen or estrogen was able to modulate this clearance.Young (3‐month‐old) male and female B/W mice cleared IgG‐sensitized mouse erythrocytes rapidly, whereas older males (13 months) and females (7 months) showed a marked impairment in their ability to clear these cells. In addition, erythrocytes sensitized with complement in the absence of antibody were cleared within 5 min in young B/W mice. Older mice showed a greater and more rapid clearance rate of these cells.Castrated female B/W mice treated with androgen implants from three weeks of age showed improved clearance of IgG‐sensitized erythrocytes at 7 months, whereas estrogen‐treated male mice showed delayed clearance.These results suggest an age‐dependent defect in the clearance of IgG‐sensitized particles, perhaps due to diminished levels of serum complement and/or saturation of Fc receptors. In addition, there is an alteration in the clearance of complement‐sensitized erythrocytes which may be related to changes in macrophage activity or enzyme inactivators of C3 and C4. The possible mechanisms responsible for the hormonal modulation of clearance are discussed in relation to the known ability of these hormones to influence autoimmune diseases.
Purification and characterization of an immunosuppressive factor from ovarian cancer ascites fluid
Authors: Oh Se‐Kyung , Moolten Frederick L. 
Published: February 2007

AbstractA nonspecific immunosuppressive factor present in malignant (ovarian carcinoma) ascites fluid has been purified by acid extraction from a high molecular weight ( > 200 000) complex followed by preparative isoelectric focusing on Bio‐lyte media. It is an acidic protein (pI = 3.6) of mol. wt. 50 000 to 52 000 as estimated by gel filtration and composed of subunits of 25000 to 26000 estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, under reducing conditions. It inhibits the phytohemagglutinin‐dependent mitogenic response of normal peripheral blood lymphocytes by 50% at 2 μg/ml concentrations in vitro and suppresses 80% of the plaque‐forming cell response to sheep erythrocytes at 100 μg per mouse in vivo. Its chemical identity with any of the known plasma proteins has not been established. Its failure to stain with periodic acid Schiff's reagent indicates its minimal content of carbohydrates. It is susceptible to tryptic and pronase digestion but insensitive to deoxyribonuclease and ribonuclease digestion. A smaller suppressive factor identified in the same fluid appears to be a lymphotoxin; it differs from the acid‐extracted nonspecific suppressive factor in its lack of susceptibility to trypsin.
Consequences of adenosine deaminase deficiency on thymocyte metabolism
Authors: Thuillier Laure , Garreau Florianne , Cartier Pierre H. 
Published: February 2007

AbstractUsing 2′‐deoxycoformycin inhibition of adenosine deaminase as a model of adenosine deaminase deficiency, the effects of 10 μM 2′‐deoxyadenosine (dAdo) on the metabolism of concanavalin A (Con A)‐stimulated rat thymocytes were studied. When dAdo and Con A were added simultaneously, a strong inhibition of the incorporation of [3H]thymidine (84%); [3H]uridine (98%) and L‐[3H] leucine (46%) in the acid‐insoluble fraction, and of [14C]formate (78%) and H14CO3− (43%) uptake is observed after 48 h of incubation. When dAdo is added after 12 h of Con A stimulation, no such inhibition is observed, but when added after 24 h of stimulation, there is an enhancement of blastogenesis as measured by nucleic acid, protein, and purine and pyrimidine base synthesis. More detailed studies of thymocytes stimulated by Con A for 0–72 h, followed by short‐term incubation periods with dAdo (1–5 h), revealed that thymocyte metabolism becomes progressively less sensitive to dAdo‐mediated inhibition during the course of blastogenesis.
Confirmation of the assignment of genes for human immunoglobulin heavy chains to chromosome 14 by analysis of Ig synthesis by man‐mouse hybridomas
Authors: Smith Moyra , Krinsky Adrienne , Arredondo‐Vega Francisco , Wang Ai‐Lan , Hirschhorn Kurt 
Published: February 2007

AbstractHybridomas were produced by fusing the NS1 mouse myeloma line, which does not produce mouse heavy chain Ig, with human peripheral B lymphocytes from a normal individual. Two vigorously growing colonies from this fusion were found to secrete human Ig heavy chains and were recloned. Two secondary clones, which secreted human chains, were again recloned. Among the tertiary clones, two were identified which produced intracellular human Ig chains, but did not secrete immunoglobulin. These tertiary clones were recloned, generating 6 quaternary clones which failed to produce human Ig heavy chains, and 15 quaternary clones which produced intracellular Ig chains. Hybrid clones from each successive subcloning were examined for their human chromosomal content and only those clones which were found to be individually chromosomally distinct, a total of 56 clones in all, were used to analyze the segregation of human chromosomes and human Ig heavy chain synthesis. Results of this study indicate concordant segregation of human Ig heavy chain synthesis and chromosome 14. These studies therefore confirm the previous assignment by C. M. Croce et al. (Proc. Natl. Acad. Sci. USA 1979. 76: 3416) of the genes for human Ig heavy chains to chromosome 14.
Lectin‐binding patterns of small lymphocytes in bone marrow, thymus and spleen: demonstration of lymphocyte subsets by quantitative radioautography
Authors: Saveriano Nellina , Drinnan Michael , Santer Vivien , Osmond Dennis G. 
Published: February 2007

AbstractCells from mouse bone marrow, thymus and spleen were exposed to 125I‐labeled concanavalin A (Con A), Lens culinaris lectin (LCL), soybean agglutinin (SBA), Helix pomatia agglutinin (HPA), phytohemagglutinin‐P (PHA‐P), peanut agglutinin (PNA), or wheat germ agglutinin (WGA) in a range of concentrations and examined radioautographically. Small lymphocytes in the three organs differed in the minimal concentration of each lectin which gave detectable surface labeling, while at optimal lectin concentrations, their labeling intensity profiles differed markedly. Inhibition by sugars demonstrated the labeling specificity. Major populations of bone marrow small lymphocytes bound WGA strongly, while Con A, SBA, HPA, PHA‐P and LCL were bound only weakly, and PNA binding was lacking. Most thymus cells bound Con A, SBA, HPA, PHA‐P and PNA strongly, WGA and LCL weakly. Subsets of bone marrow and thymus small lymphocytes differed from the major populations in their lectin‐binding intensities. Spleen small lymphocytes were heterogeneous in the binding of each lectin. However, a major population bound LCL exceptionally strongly, while few cells bound PNA. Using a panel of lectins under standardized conditions, these studies show distinctive lectin‐binding patterns for small lymphocytes in the bone marrow, thymus and spleen, respectively. Major and minor cell populations are distinguishable in each organ, providing an approach to discriminating lymphocyte lineages, subtypes and differentiation stages.
Regulation of delayed‐type hypersensitivity. VII. The role of I‐J subregion gene products in the inhibition of delayed‐type hypersensitivity to major histocompatibility antigens by specific suppressor T cells
Authors: Liew Foo Y. 
Published: February 2007

AbstractSuppressor T cells for delayed‐type hypersensitivity (DTH) to alloantigens are induced by injecting mice intravenously with a high dose of X‐irradiated allogeneic cells. Using the same protocol, suppression of DTH directed against H‐2 subregion products could also be induced, provided that the H‐2 incompatibility between the cells used for the induction of suppression and the recipients includes the I‐J subregion genes. Thus, the I‐J subregion difference is both necessary and sufficient for the induction of suppression of DTH to the whole or part of the H‐2 gene products. The suppression appears to be mediated by antigen‐specific suppressor T cells which recognize the allo‐I‐J molecules and are able to suppress the DTH response to other H‐2 subregion gene products in an associative recognition manner. T cells from (B10 × BALB/c)F1 mice suppressively primed against B10.A(5R) cells (directed against JkEk antigens), when adoptively transferred to normal syngeneic recipients, were capable of suppressing the hosts' DTH response to B10.A(4R) cells (KkAk antigens) when the recipients were challenged with [B10.A(4R) × B10.A(5R)]F1 cells (KkAk × JkEk). The recipients express normal DTH reactivity to B10.A(4R) cells when challenged with a mixture of B10.A(4R) and B10.A(5R) cells (KkAk + JkEk). These results provide direct evidence that when functioning as alloantigens, the I‐J determinants preferentially induce suppressor T cells which specifically impair the immune response to the I‐J molecules as well as other H‐2 gene products if they are physically associated with the I‐J determinants. The role of I‐J subregions as the suppressor genes is discussed in terms of the possible application in transplantation immunity and the host's defence against infectious diseases.
Primary antibody responses to hapten‐modified syngeneic cells: exceptional immunogenicity of erythrocytes
Authors: Nakashima Izumi , Takashi Munehisa , Nagase Fumihiko , Kato Nobuo 
Published: February 2007

AbstractIntravenous injection of fluorescein isothiocyanate‐modified syngeneic spleen cells (FITC‐SSC) into mice induced T cell‐independent, anti‐hapten plaque‐forming cell responses. In contrast to the high immunogenicity of FITC‐coupled SSC or bone marrow cells, thymus, lymph node or peritoneal exudate cells were poorly immunogenic. Further analysis showed that FITC‐syngeneic peripheral blood red cells were as immunogenic as FITC‐SSC containing a similar number of red cells. The immunogenicity of the red cells was confirmed by treatment of FITC‐SSC with 0.83% ammonium chloride before sensitization with FITC. This procedure almost totally abolished the immunogenicity regardless of the concentration of hapten with which they were sensitized. In addition, heat treatment or fixation with glutaraldehyde destroyed the immunogenicity of FITC‐SSC.
Immunoregulatory circuits which modulate responsiveness to suppressor cell signals: characterization of an effector cell in the contrasuppressor circuit
Authors: Green Douglas R. , Eardley Diane D. , Kimura Art , Murphy Donal B. , Yamauchi Katsumi , Gershon Richard K. 
Published: February 2007

AbstractSpleen cells from neonatal animals, placed in culture for 6 days spontaneously develop the ability to block the activity of suppressor T cells, a phenomenon that is referred to as contrasuppression. The effector cell which is derived from the interactions among the cells which comprise a contrasuppressor “circuit” is an Ly‐1 T cell. It can be separated from Ly‐1 helper cells by three criteria other than function: its generation is dependent on Ly‐2+ cells, it is I‐J+, and it sticks to the Vicia villosa lectin. Those cells which deliver help to B cells under the experimental conditions studied are not dependent on Ly‐2+ cells for generation and neither express determinants that our anti‐I‐J antisera recognize nor stick to V. villosa.The mechanism by which these Ly‐1 contrasuppressor cells function was elucidated by adding them to “intermediate cultures” containing activated Ly‐2 suppressor cells and in vivo immunized Ly‐1.1‐congenic helper cells. After 48 h in these intermediate cultures, the neonatal Ly‐1.2 contrasuppressor cells and the Ly‐2 suppressor cells were removed by treatment with the appropriate antiserum plus complement. The remaining activity of the in vivo generated Ly‐1.1 helper cells was assayed in fresh cultures of B cells. The contrasuppressor cells not only diminished suppression of the Ly‐1 helper cells by the Ly‐2 suppressor cells in the intermediate culture, but actually conferred a state of relative resistance to suppression upon the helper cells. This state persisted after the contrasuppressor cells were removed. Why such a cellular circuit, which confers resistance to suppression, might be beneficial to neonatal mice and how considering its attributes might help explain some immunological paradoxes is the subject of discussion.