bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of cell‐mediated lysis by xenoantibodies reactive with effector T lymphocytes
Authors: Rabinowitz Ruth , Laskov Reuven , Schlesinger Michael 
Published: February 2007

AbstractThe aim of the present study was to determine whether rabbit antisera against various murine tissue antigens contain antibodies that affect the activity of cytotoxic T lymphocytes in the absence of complement. Following heat inactivation, the xenoantisera were absorbed with mouse liver and kidney and tested for their capacity to inhibit cell‐mediated lysis (CML). In the presence of complement (C), rabbit anti‐brain antiserum (RABr), rabbit anti‐thymus antiserum (RAT) and rabbit anti‐boiled thy‐ mus antiserum (RABT) lysed effector T cells, and CML was abolished. In the absence of C, RAT maintained its strong inhibitory activity on CML, RABr had no inhibitory effect, whereas only some batches of RABT were effective. Monovalent Fab fragments of RAT inhibited CML as effectively as intact antibody molecules. The activity of RAT could be removed by absorption with T and B lymphocytes of various sources. Inhibitory antibodies could be removed by absorption with C3H B lymphoma cells and upon elution from antibody‐coated cells proved again highly effective in inhibiting CML. These results show that RAT contains antibodies which react with determinants shared by T and B lymphocytes and which block the activity of cytotoxic T cells.
Phosphorylcholine‐binding hybridoma proteins of normal and idiotypically suppressed BALB/c mice. I. Characterization and idiotypic analysis
Authors: Berek Claudia , Schreier Max H. , Sidman Charles L. , Jaton Jean‐Claude , Kocher Hans P. , Cosenza Humberto 
Published: February 2007

AbstractThe immune response of BALB/c mice to phosphorylcholine (PC) is dominated by an antibody bearing the idiotype of the myeloma protein TEPC 15 (MP T15). Anti‐PC antibody of a different idiotype can be elicited in BALB/c mice by neonatal suppression with an anti‐T15 idiotypic antiserum (anti‐Id‐T15).In an attempt to further characterize the immune response to PC, spleen cells of normal and idiotypically suppressed mice have been fused with the myeloma line X63‐Ag8, and hybrid lines secreting anti‐PC antibodies have been isolated. The antibodies were characterized by two‐dimensional gel electrophoresis and their affinity for Pneumococcus pneumoniae was measured. Using both an A/J and a rabbit anti‐Id‐T15 serum, we could show that 4 out of 5 hybridomas obtained from normal BALB/c spleen cells secreted antibodies which, within the limits of the analysis, were idiotypically and structurally indistinguishable from MP T15 (T15+). Hybridomas obtained from suppressed BALB/c mice, on the other hand, secreted anti‐PC antibodies which differed idiotypically from MP T 15: of the six lines, two were negative for T15 idiotopes (T15−), while four showed some cross‐reactivity with the T15 idiotype (T15cr). All six, however, showed structural differences in one or more immunoglobulin chains.Inhibition of anti‐PC plaque‐forming cells induced in neonatally suppressed mice revealed that the idiotypic spectrum of the hybridoma proteins was representative of clones arising under such conditions in BALB/c mice. The majority of the anti‐PC antibodies in idiotypically suppressed mice still bear idiotopes resembling MP T15. Only a minority, less than 20%, are truly T15−.
H‐2 genetic control of the response of T lymphocytes to insulins. Priming of nonresponder mice by forbidden variants of specific antigenic determinants
Authors: Cohen Irun R. , Talmon Janet 
Published: February 2007

AbstractH‐2 gene control of the response of T lymphocytes to antigenic determinants of ungulate insulins has been studied. We injected H‐2‐congenic mice with different insulins emulsified in complete Freund's adjuvant and measured the proliferative response in vitro of the draining lymph node cells to various related insulins. Two groups of determinants were antigenic: the A chain loop determinant present on bovine and sheep insulins, but absent on pig insulin, and a pig‐associated determinant(s) also shared by bovine and sheep insulins. The responses to these two sets of determinants were controlled by H‐2 genes as follows: (a) The pig‐associated determinant(s) was antigenic for H‐2d but not for H‐2′ or H‐2k mice. (b) The A chain loop determinant was immunodominant over the pig‐associated determinant(s) for H‐2dmice. In the presence of the A chain loop determinant, H‐2d mice did not respond to the pig‐associated determinant(s) on the same molecule. (c) H‐2d mice did not distinguish between the bovine and sheep variants of the A chain loop that differed by substitution of one amino acid. (d) In contrast, H‐2k mice responded only to the sheep variant, while H‐2b mice responded primarily to the bovine variant of the A chain loop determinant. (e) However, injection of H‐2b mice with “forbidden” sheep insulin primed them for an in vitro response to the “permitted” bovine variant of the A chain loop determinant. Similarly, some H‐2k mice injected with forbidden bovine insulin responded in vitro to the permitted sheep variant of the A chain loop determinant. Thus, H‐2 gene products decided whether the immune response would express an affinity for the specific immunizing antigen itself and/or for a closely related variant.
Idiotypic profile of the response to phosphorylcholine induced in the absence of the homologous antigen
Authors: Cammisuli Salvatore , Cosenza Humberto 
Published: February 2007

AbstractIn the absence of the homologous antigen, an anti‐phosphorylcholine (PC) plaque‐ forming cell (PFC) response has been induced in vitro which is restricted to the TEPC 15 idiotype (T15). Anti‐T15 antibodies were used to focus either the keyhole limpet hemocyanin (KLH) or the fowl gamma‐globulin (FGG) carrier molecules on the membrane of B cells carrying the T15 idiotype on their immunoglobulin receptors; thereafter, these cells were allowed to cooperate in vitro for 5 days with T cells primed to the appropriate carrier molecule. A response, virtually 100% T15+, could be induced both in normal BALB/c and in T15 neonatally suppressed mice which had lost the T15 + clonal dominance. The magnitude of this response is comparable to that obtained in the presence of the PC antigen. The role of the membrane‐bound immunoglobulin receptor (sIg) in the expression of different anti‐PC clones was also investigated. We have focused either the KLH or the FGG carrier molecules on the membrane of B cells via anti‐H‐2 antibodies and then cultured these cells for 5 days with the appropriate carrier‐specific T cells. Under these conditions, B cells are activated in the absence of interaction at the sIg. The idiotypic profile of the anti‐PC PFC obtained with the anti‐H‐2‐mediated activation was then compared with the profile of the anti‐PC response obtained in the presence of PC antigen. Since similar idiotypic profiles were obtained in both cases, it can be excluded that sIg plays a direct role in favoring the expression of T15+ over T15− anti‐PC clones.
Partial amino acid sequence of the precursors of blocked heavy and light chains from C 3 H mouse myeloma 5563
Authors: Singer Helen H. , Gates Frederick T. , Kindt Thomas J. , Williamson Alan R. 
Published: February 2007

AbstractA messenger RNA fraction from the C 3 H mouse myeloma 5563 was used to direct the synthesis of heavy (γ2J) and light (χ) chain precursors. The synthetic products were radiolabeled by inclusion of [3H] or [35S] amino acids in a wheat‐germ cell‐free translation system. Precursor peptides for both H and L chains were indicated by comparison by polyacrylamide gel analysis of apparent molecular weights of chains synthesized in vitro vs. in vivo. The nonglycosylated H chain synthesized in vivo in the presence of tunicamycin was used for comparison. This approach should be generally applicable for the demonstration of precursor forms of N‐glycosylated polypeptides. Following immunoprecipitation and preparative polyacrylamide gel electrophoresis, the isolated chains were subjected to automated Edman degradation. The amino acid sequence data obtained for these precursors were significantly different from those reported for BALB/c immunoglobulins. The 5563 H chain precursor bears little homology to the previously reported H chain precursor from MOPC 315 (IgA) (Jilka, J. A. and Pestka, S., Proc. Nat. Acad. Sci. USA 1977. 74: 5692). The 5563 H chain can be assigned to a heretofore undescribed H chain variable region subgroup on the basis of partial sequence data. The amino terminal sequence of the 5563 L chain precursor has maximum homology (25‐55%) to the sequence of the precursor peptide of MOPC41 χ chain.
Molecular identification of T cell‐specific antigens on human T lymphocytes and thymocytes
Authors: Andersson Leif C. , Karhi Kimmo K. , Gahmberg Carl G. , Rodt Hans 
Published: February 2007

AbstractWe have identified membrane glycoproteins which carry T cell‐specific antigens on human T lymphocytes and thymocytes. Purified cells were surface‐labeled with NaB3H4 after treatment with neuraminidase and galactose oxidase. Immunoprecipitations were performed with rabbit anti‐human T cell‐specific antibodies using co precipitation with protein A‐containing staphylococci strain Cowan I. The labeled membrane glycoproteins and the precipitates were subjected to polyacrylamide slab gel electrophoresis and visualized by fluorography.The antibodies specifically precipitated 4 proteins called GP200, GP180, GP165 and GP160 (mol. wts. = 200000, 180000, 165000 and 160000) from surface‐labeled T lymphocytes and low‐density (medullary) thymocytes. The GP200 and GP180 were not labeled on high‐density (cortical) thymocytes. A protein with a mol. wt. of 45000 was precipitated from thymocytes. Another glycoprotein on T lymphocytes and thymocytes with a mol. wt. similar to that of mouse and rat Thy‐1 or Θ antigen (mol. wt. 25000) reacted with the antibodies.
T‐T cell interactions during in vitro cytotoxic T lymphocyte responses. III. Antigen‐specific T helper cells release nonspecific mediator(s) able to help induction of H‐2‐restricted cytotoxic T lymphocyte responses across cell‐impermeable membranes
Authors: Pfizenmaier Klaus , Delzeit Rosemarie , Röllinghoff Martin , Wagner Hermann 
Published: February 2007

AbstractT helper cell induction and the specificity of T cell‐mediated help as generated during alloreactive and H‐2‐restricted, virus‐ or hapten‐specific cytotoxic T lymphocyte (CTL) responses have been compared. With the use of a double‐chamber culture system, it was possible to dissect and separately analyze the induction phase of T helper cells from the T helper cell effector function. The data obtained revealed that during alloreactive as well as H‐2‐restricted T cell responses, antigen‐specific T helper cells are induced. Upon specific restimulation of T helper cells, helper cell function is mediated across a cell‐impermeable membrane via soluble products in an apparently nonspecific and nonrestricted manner. The data suggest that similar rules govern T‐T cell interactions in alloreactive and H‐2‐restricted CTL responses.
Original H‐2d and alien H‐2k‐like antigens of a BALB/c fibrosarcoma as defined by in vitro and in vivo studies of cell‐mediated immunity
Authors: Sensi Marialuisa , Carbone Giusi , Parmiani Giorgio 
Published: February 2007

AbstractThe present study examines the immunosensitivity and the immunogenicity of both original H‐2d and alien H‐2k‐like antigens of the BALB/c (H‐2d) fibrosarcoma C‐1 as detected by in vitro and in vivo cell‐mediated cytotoxicity (CMC) assays. It was found that 51Cr‐labeled C‐1 cells were lysed in vitro by C 57 BL/6 anti‐H‐2d lymphocytes. The specificity of this reaction was shown by cold inhibition experiments in which the anti‐H‐2d cytotoxic activity on YC8 (H‐2d) targets was inhibited by unlabeled YC8 or C‐1 but not by C3UR11 (H‐2k) tumor cells. Both Dd‐ and Kd‐encoded antigens were recognized by appropriate cytotoxic effectors. The immunogenicity of H‐2d antigens of C‐1 was revealed by the ability of C 57 BL/6 anti‐C‐1 lymphocytes to lyse YC8 targets. The expression of H‐2k‐like alien alloantigens on C‐1 was indicated by the finding that anti‐H‐2k cytotoxic T lymphocytes (CTL), generated by culturing BALB/c spleen cells immune to BALB.K (H‐2k), C3Hf (H‐2k) or A (H‐2a = H‐2k/d) tissues with the cells of the same strain used for immunization, lysed C‐1 targets. The cytotoxicity of these anti‐H‐2k CTL against C 3 UR11 (H‐2k) targets could be specifically inhibited by cold C 3 UR 11 or C‐1 cells but not by two other BALB/c tumors. Using recombinant H‐2‐congenic mice, it was shown that both Dk and Kk antigens were recognized by CTL on C‐1 cells. The immunogenicity of the H‐2k‐like antigens, however, could not be detected in vitro. In fact, effector spleen cells from BALB/c mice immune to C‐1 did not develop any detectable cytotoxicity against C 3 UR 11 targets as assayed either by a direct in vitro test or after in vitro restimulation with C‐1 sarcoma cells. A similar experimental design was adopted in Winn assays carried out by mixing spleen cells of BALB/c immune mice with either C‐1 or C3 UR 11 targets and injecting the mixtures in BALB/c or hybrid recipients. These in vivo tests revealed the presence of both H‐2d (Kd and Dd) and H‐2k‐like (Kk and Dk) antigens on C‐1. At variance with the in vitro CMC assays, however, the Winn assay also detected the immunogenicity of the H‐2k alien antigens, since BALB/c anti‐C‐1 spleen cells were able to significantly reduce the growth of C 3 UR 11 lymphoma cells in (BALB/c × C 3 Hf)F1 hosts.
Change in mixed lymphocyte culture reactivity following allosensitization between DLA‐identical dog sibs
Authors: Gluckman Jean‐Claude 
Published: February 2007

AbstractThe mixed lymphocyte culture (MLC) is known to react to major histocompatibility complex disparities but is insensitive to minor histocompatibility antigens. To determine which modifications could amplify reactivity to these antigens, we have studied the effects of presensitization on normally nonresponsive MLC in dogs. Lymphocytes, primed in vitro to and restimulated with cells of a DLA‐identical sib, did not react to these specific cells, in contrast to normal proliferation to other stimulators. However, lymphocytes obtained after in vivo sensitization against a DLA‐identical donor showed increased reactivity to the donor in approximately half of the recipients. In comparison to primary MLC responses between DLA‐mismatched individuals, the [3H] thymidine uptake was less important in this reaction, and peak incorporation was usually not accelerated. This response appeared to be specific in that responsiveness to third‐party cells was not increased, and, alternatively, immunization against a DLA haplo‐identical donor did not modify reactivity to DLA‐identical cells. This increased reactivity after alloimmunization may reflect differences in minor histocompatibility antigens although the skin graft survival time was not significantly shorter in MLC responders than in nonresponder recipients. It seems that in vivo priming is required to expand the number of cells specific for these antigens and to enable detection of proliferation in MLC.
Murine embryonic blood between day 10 and 13 of gestation as a source of immature precursor B cells
Authors: Melchers Fritz , Abramczuk Jan 
Published: February 2007

AbstractPre‐B cells which show a delayed development of responsiveness to the B cell mitogen lipopolysaccharide (LPS) are found in murine embryonic blood between day 10 and 14 of gestation. The highest frequency of pre‐B cells in embryonic blood is found at day 12 of gestation. All pre‐B cells of embryonic blood, isolated at different days of gestation, develop responsiveness in vitro to LPS at the same time, i.e. around day 14 of gestation, yielding a peak of LPS‐induced IgM plaque‐forming cells at the equivalent of day 19 of gestation. Dextran sulfate supports the development of pre‐B cells into LPS‐reactive B cells; by itself, however, it does not stimulate these B cells into IgM plaque‐forming cells. The wave of pre‐B cells in embryonic blood occurs parallel in time to that found previously in placenta. Fetal liver and yolk sac, at this time of embryonic development, do not contain significant numbers of pre‐B cells, although they are connected with the placenta and in contact with embryonic blood by circulation.
The in vitro immune response in the absence of serum and its proteins: stimulating activity of zymosan
Authors: Burger Mikulas , Hess Max W. , Cottier Hans 
Published: February 2007

AbstractIn the absence of serum and its components, zymosan, together with 2‐mercaptoethanol present in the medium, stimulated the in vitro primary immune response. Zymosan was effective at a concentration of as low as 2.5 μg/ml. Removal of macrophages using iron powder resulted in higher recoveries of plaque‐forming cells in the presence of zymosan but not of fetuin. Since insoluble zymosan may be easily removed from the culture, the test system described might be suitable for the identification of specific control factors secreted by cells during the in vitro immune response.
Characterization of mouse thymocyte and peripheral lymphocyte xenoantigens by two‐dimensional electrophoresis
Authors: Hoessli Daniel C. , Vassalli Pierre , Pink J. Richard L. 
Published: February 2007

AbstractTwo‐dimensional electrophoresis was used to analyze the surface glycoproteins of murine thymocytes and lymph node cells. Two‐dimensional maps of unselected, radioiodinated lymphocyte surface proteins were complex, showing at least 20 different components, but simpler patterns were obtained by using rabbit antibodies directed against the surface proteins of a T lymphoma cell line, to precipitate xenoantigens from lysates of radioiodinated or biosynthetically labeled thymocytes and lymph node cells. These xenoantibodies precipitated 12–13 distinct components from each cell type, of which all but 3 were sialoglycoproteins. Two types of difference between the surface glycoproteins of thymocytes and peripheral lymphocytes could be detected. First, higher mol. wt. glycoproteins and Thy‐1 are more acidic in peripheral lymphocytes than in thymocytes, and this difference disappears after neuraminidase treatment. One additional high mol. wt. glycoprotein is also detectable in peripheral lymphocytes, probably reflecting the greater carbohydrate complexity of these molecules, when expressed on such cells. Second, 3 glycoproteins are strongly labeled only on thymocytes, and 3 others only on peripheral lymphocytes. These 6 glycoproteins might represent genuine differentiation antigens.
Plasma membrane cholesterol regulates human lymphocyte cytotoxic function
Authors: Dabrowski Marek P. , Peel William E. , Thomson Alasdair E. R. 
Published: February 2007

AbstractCell cholesterol is believed to be confined mainly to the plasma membrane. Treatment here of human peripheral blood lymphocytes with cholesterol‐free and cholesterol‐containing liposomes to effect, respectively, decreases or increases in cholesterol content measurable by chemical analysis, markedly altered effector functions of the cells. Depletion of cholesterol evoked inhibition of spontaneous and phytobemag‐glutinin‐dependent lymphocyte cytotoxicity against allogeneic target cells. Opposite effects resulted from cholesterol enrichment, with PHA‐dependent and antibody‐dependent cytotoxicities increasing significantly. Treatment, instead, with the known inhibitor of cholesterol biosynthesis, 25‐hydroxycholesterol, had suppressive effects like those resulting from lowering the cholesterol level physically by liposome treatment. Our data suggest that the plasma membrane cholesterol content of different categories of lymphocytes in man is both essential and regulatory for their cytotoxic function.
Interferon induced in human leukocytes by mitogens: production, partial purification and characterization
Authors: de Ley Marc , van Damme Joseph , Claeys Hendrik , Weening Hans , Heine Jochen W. , Billiau Alfons , Vermylen Carl , de Somer Piet 
Published: February 2007

AbstractInterferon was induced in leukocyte suspensions from human buffy coats by exposure to phytohemagglutinin P, concanavalin A (Con A) and staphylococcal enterotoxin A, under a variety of cell culture conditions. Con A was found to rapidly (within 12 h) induce high yields of antiviral activity (1.5 units/1000 cells). Lesser yields were obtained with the other two mitogens studied. The interferon was partially purified to a spec. act. around 105.3 units/mg protein, by batch adsorption on controlled‐pore glass (CPG) beads and desorption by ethylene glycol. This material was characterized as containing mainly γ‐type interferon. Specifically on gel filtration, a fraction of 45 000 daltons was obtained which could account for virtually all antiviral activity present in the starting material. Furthermore, the ethylene glycol‐eluted antiviral activity was acid‐labile, serologically distinct from a and β‐type interferon and strictly species‐specific (no activity detectable on any of the available cell species sensitive to α and β‐type interferon). The crude culture supernatant also contained some antiviral activity which resembled β‐type interferon in that it adsorbed to CPG, could be desorbed by pH 2 buffer, was acid‐resistant and could be neutralized by a specific anti‐fibroblast interferon antiserum. The CPG/ethylene glycol‐purified γ‐type interferon preparation was found to inhibit the growth of certain lymphoblastoid cells (Daudi and Molt‐4). It also potentiated natural killer activity of fresh donor lymphocytes. In both respects, the γ‐type interferon preparation was not significantly more active than preparations of a and β‐interferon of similar antiviral potency.
Characterization of human lymphocytes which proliferate “spontaneously” in vitro
Authors: Treves Abraham J. , Barak Vivian , Fuks Zvi 
Published: February 2007

AbstractHuman peripheral blood lymphocytes proliferate “spontaneously” in vitro following the reduction in the proportion of monocytes in culture. This cell proliferation, which takes place in the absence of any extrinsic antigenic stimulation, was found to reside in a small fraction of a non‐T non‐B cell population which was also Fc receptor‐negative. Concomitant with the in vitro proliferation of the monocyte‐depleted cells, an increase in the proportion of E rosette‐forming cells was observed. Hence, in addition to the regulation of spontaneous proliferation of lymphocytes, it is suggested that monocytes may also be involved in the regulation of the proportion of T cells or in expression of the E‐rosetting marker.
Helper cell analysis in cytotoxic T lymphocyte responses I. Activation of specific and cross‐reactive helper effects in two hapten‐modified self responses
Authors: Levy Robert B. , Fujiwara Hiromi , Shearer Gene M. 
Published: February 2007

AbstractC 3 H/HeN mice were immunized by skin painting with trinitrochlorobenzene or by inoculation of fluorescein isothiocyanate (FITC)‐conjugated syngeneic cells. Approximately four weeks later, spleen cells were removed, irradiated, and cocultured with spleen cells from normal mice. These cultures were stimulated with syngeneic cells conjugated with different concentrations of trinitrobenzene sulfonate (TNP‐self) or FITC (FITC‐self). The results demonstrate (a) appreciable helper cell activity from TNP‐self and FITC‐self‐primed mice, as determined by enhanced hapten‐specific cytotoxic T lymphocyte (CTL) responses, (b) that FITC helper activity enhanced the FITC‐self CTL more efficiently than the TNP‐self CTL response, and vice versa, (c) an alloantigenic stimulating population failed to activate TNP‐self helper activity and (d) that the helper activity was not exclusively specific, since FITC helpers did enhance the anti TNP CTL response, and TNP helpers could enhance the anti‐FITC‐self CTL response. The results of this study indicate that these cell‐mediated lympholysis models permit an analysis of hapten specificity and cross‐reactivity at the different levels of cellular interaction involved in the generation of an H‐2‐restricted CTL response.