bluuebunny/crossref_metadata_2025_split huggingface dataset:
An immunopathologic study of a 330-kD protein defined by monoclonal antibodies and reactive with anti-RTE alpha 5 antibodies and kidney eluates from active Heymann nephritis.
Authors: Ronco P , Neale T J , Wilson C B , Galceran M , Verroust P 
Published: December 2022

Abstract
There is evidence indicating that the glomerular Ig deposits of Heymann's nephritis (HN)--a model of epimembranous glomerulonephritis--may be formed at least in part in situ by binding of free circulating antibody with brush border (BB) antigen expressed by glomerular epithelial cells. In this work, we provide evidence that a 330-kD protein defined by seven monoclonal antibodies is responsible for HN. 1) Ig eluted from glomeruli of rats with HN induced classically with crude BB preparation bind specifically the 330-kD antigen; 2) passive immunization with monoclonal antibodies induces epimembranous glomerular Ig deposits; 3) active immunization with the 330-kD antigen induces proteinuric glomerulonephritis; 4) the 330-kD antigen was present in the nephritogenic preparation purified by Edgington, Glassock, and Dixon, because it was identified by the corresponding heterologous antisera. These results, obtained by a completely different approach, confirm and extend those of Kerjaschki and Farquhar and provide a link with the classical studies on HN.
Sequential synergistic effect of interleukin 2 and interferon-gamma on the differentiation of a Tac-antigen-positive B cell line.
Authors: Nakagawa T , Nakagawa N , Volkman D J , Fauci A S 
Published: December 2022

Abstract
The presence of Tac-antigen (Tac-Ag) on human B lymphocytes and its functional significance with regard to the ability of interleukin 2 (IL 2) to modulate B cell differentiation is currently an area of high interest. An Epstein-Barr virus-transformed B cell line (CB) that secretes IgG was 30 to 40% Tac-Ag+ and was used as a model for examining the role of Tac-Ag and IL 2 in B cell differentiation. Recombinant IL 2 alone was found to have a modest but significant effect on CB in enhancing IgG secretion, increasing the plaque-forming cell response from 637 to 1734 at high concentrations (1000 U/ml IL 2) and to 888 at lower concentrations (100 U/ml). In contrast, recombinant interferon-gamma (IFN-gamma) alone had no effect on the differentiation of CB. However, both factors together showed marked synergy in increasing the number of plaque-forming cells to over 3000 by using only 10 U/ml of IFN-gamma and 100 U/ml of IL 2. These two factors were shown to act sequentially in that IL 2 was needed initially, while IFN-gamma was required for the next differentiation step into IgG-secreting cells. The effect of IL 2 on stimulating differentiation was blocked by anti-Tac, indicating that the action of IL 2 is mediated through its Tac-Ag receptor. CB cells were also sorted into Tac+ and Tac- populations and were cultured separately. In 2 wk, both populations reverted to the pattern of the original cell line. Moreover, cell cycle analysis when using double staining procedures indicated that Tac-Ag on the cell surface of CB appears and disappears according to the stage of the cell cycle, and that Tac is most strongly expressed in the S and G2 + M phases. Thus, the present study suggests that certain B cells are capable of responding to sequential stimulation by IL 2 and IFN-gamma with terminal differentiation into Ig-secreting cells, and that the amount of Tac-Ag expression is cell cycle dependent.
A mitogenic factor for endothelial cells obtained from mouse secondary mixed leukocyte cultures.
Authors: Watt S L , Auerbach R 
Published: December 2022

Abstract
Supernatants from secondary mixed leukocyte cultures (MLC) are capable of stimulating both endothelial cell proliferation and endothelial cell chemokinesis. The proliferation factor(s) has been subject to further biochemical characterization. At least one factor is precipitable by 30% ammonium sulfate, a procedure that separates this factor from the chemokinesis-inducing factor(s) and most other growth-stimulating lymphokines. The partially purified lymphokine preparation can stimulate growth of microvascular endothelial cells, yet fails to induce proliferation of large vessel endothelium and a variety of other cell types. Addition of indomethacin to the MLC medium leads to an increase in endothelial cell mitogenic activity. Chromatography on S-200 Sephacryl suggests a m.w. greater than 200,000 when eluted in isotonic saline, whereas the apparent m.w. is less than 30,000 when the material is eluted from the same column with 0.5 M ammonium acetate. The proliferative activity is stable to acid (pH 2) but not to heat treatment at 50 degrees C. Although the factor is resistant to trypsin digestion, it is sensitive to digestion with pronase, suggesting that it is a protein. The potential importance of endothelial cell-specific lymphokines in the vascular responses accompanying inflammation and disease-associated neovascular reactions is discussed.
Histamine-producing cell stimulating factor (HCSF) and interleukin 3 (IL 3): evidence for two distinct molecular entities.
Authors: Dy M , Lebel B , Schneider E 
Published: December 2022

Abstract
Because homogeneously purified interleukin 3 (IL 3) can induce an increase in histamine synthesis by normal bone marrow cells like histamine-producing cell stimulating Factor (HCSF), it has been suggested that HCSF and IL 3 might be identical. In this paper, we provide evidence that HCSF activity can be obtained without IL 3 activity (determined by the proliferation of an IL 3-dependent cell line). This distinction between HCSF and IL 3 has been achieved in three different ways: a) biochemical separation of HCSF from IL 3 in crude secondary MLC supernatants with description of different physicochemical characteristics of the two molecules; b) demonstration of an HCSF activity devoid of IL 3 activity in P388D1 conditioned medium, with the same characteristics as HCSF produced during secondary MLC but different from WEHI-3-derived HCSF activity resulting from IL 3; c) demonstration of a lack of inhibition of HCSF-induced histamine synthesis by anti-IL 3 immunoglobulins that clearly diminish IL 3-induced histamine production. These results demonstrate that two distinct factors (IL 3 and HCSF) promote histamine synthesis, but that IL 3 has more general effects on hemopoietic cells, whereas HCSF seems to be restricted to histamine-producing cells.
p150,95, the third member of the Mac-1, LFA-1 human leukocyte adhesion glycoprotein family.
Authors: Springer T A , Miller L J , Anderson D C 
Published: December 2022

Abstract
Monoclonal antibodies specific for p150,95, a third member of the Mac-1 and lymphocyte function-associated antigen-1 (LFA-1) leukocyte adhesion protein family, have been identified and used to study the biochemistry and cellular expression of p150,95. p150,95 is a noncovalently associated heterodimer containing alpha X and beta subunits of Mr = 150,000 and 95,000 respectively. Findings suggest that the p150,95 alpha X beta complex shares a common beta subunit with the alpha L beta LFA-1 and alpha M beta Mac-1 complexes. Co-precipitation experiments demonstrated identity between the p150,95 molecule precipitated by anti-beta MAb and by p150,95-specific MAb. Patients with a previously demonstrated genetic deficiency in Mac-1 and LFA-1 fail to express p150,95. Deficiency of the Mac-1, LFA-1, and p150,95 alpha beta complexes on the surface of patient cells appears due to a defect in the common beta subunit. The lack of cross-reaction of p150,95-specific MAb with LFA-1 and Mac-1, which appear to utilize identical beta subunits, suggests that the determinant is specified by the alpha X rather than the beta subunit of p150,95. The data suggest that alpha X is yet a third member of a family of alpha subunit proteins that associate with a common beta subunit, are differentially regulated in leukocyte differentiation, and function in adhesion reactions. p150,95 is normally expressed on blood monocytes and granulocytes. Chemoattractants such as f-Met-Leu-Phe stimulate a rapid, fivefold increase in surface expression that is not dependent on protein synthesis and appears to reflect mobilization of an intracellular latent pool. The intimate relation between the lack of chemoattractant-stimulated upregulation of p150,95 and Mac-1 by patient granulocytes and their failure to upregulate adhesiveness to these same stimuli in vitro, or to diapedese and migrate into inflammatory sites in vivo, is discussed.
Phospholipase A2 stimulation during cell secretion in rat basophilic leukemia cells.
Authors: Garcia-Gil M , Siraganian R P 
Published: December 2022

Abstract
The bridging of IgE receptors on rat basophilic leukemia cells (RBL-2H3) results in a number of biochemical events that accompany histamine secretion. Prominent among these is the release of arachidonic acid from cellular phospholipids, which could be due to the activation of phospholipase enzymes. In the present experiments we studied the intracellular activation of phospholipase A2 (PLA2) during histamine release. RBL-2H3 cells were stimulated through the IgE receptor, and the homogenates were prepared and tested for phospholipase A2 activity on 1-stearoyl-2-[14C]arachidonyl-sn-3-phosphatidylcholine. The amount of activity in the homogenates was dependent on the concentration of secretagogue used to activate the cells. Under optimal conditions there was a 1.86 +/- 0.12-fold (mean +/- SEM, N = 44) increase in the activity found in homogenates of stimulated cells. Activity was present in homogenates prepared 30 sec after cell activation, was optimal between 5 and 10 min, and decreased later. In time course experiments the PLA2 activation preceded histamine release. The activation of the enzyme in the cell occurred in the presence of 10 microM EGTA in the extracellular medium, which completely inhibited release of arachidonic acid and histamine. However, the activity of the enzyme required Ca2+. The PLA2 activity in the homogenates and the extent of cell stimulation for histamine release were maximal at the same concentration of antigen, and both were blocked by the addition of a monovalent hapten. The enzyme in the homogenates was capable of cleaving arachidonic acid from different phospholipids. The production of lysophospholipids could play a critical role in histamine release from cells. These results demonstrate the activation of PLA2 enzyme in cellular homogenates during the secretory process.
Modulation of cyclic AMP-dependent protein kinase isozyme expression associated with activation of a macrophage cell line.
Authors: Justement L B , Aldrich W A , Wenger G D , O'Dorisio M S , Zwilling B S 
Published: December 2022

Abstract
We have used the RAW 264.7 macrophage (MO) cell line to study cAMPdPK isozymes during activation by lymphokine (LK) and lipopolysaccharide (LPS). Untreated cells were found to have two isozymes of cAMPdPK in their cytosol. PKI and PKII were differentiated based on the Mr of their regulatory subunits (RI, 45,500; and RII, 52,000, respectively) as determined by photoactivated incorporation of the cAMP analog 8-N3-[32P]cAMP. Loss of the RI subunit of PKI occurred in association with activation of the cell line by suboptimal concentrations of LK and LPS (1/40 dilution, 1 ng/ml) or high concentrations of LPS alone (10 ng/ml to 100 micrograms/ml). No modulation of the RII subunit of PKII was observed under these conditions. The loss of RI was dependent on the addition of a triggering signal to the MO. Treatment of RAW 264.7 cells with LK alone at dilutions from 1/10 to 1/1280 was not sufficient to cause a disappearance of the RI subunit from the cytosol or to induce antitumor activity. The addition of a suboptimal concentration of LPS after LK or a high dose of LPS alone was required for acquisition of cytolytic activity and loss of RI. The kinetics for the disappearance of RI from treated cells were found to be identical after activation with either LK and LPS or high concentrations of LPS alone. RI could no longer be detected in the cytosol 8 hr after the addition of activating agents. The antitumor activity of the RAW 264.7 cell line was transiently expressed after activation. Cells no longer exhibited tumoricidal activity 48 hr after the removal of activating agents. It was observed that the loss of cytolytic function was accompanied by the reexpression of RI in the cytosol. This study provides evidence that modulation of cAMPdPK isozymes occurs during activation, suggesting a potential mechanism for controlling the effects of cAMP on the MO.
Chemotaxis of large granular lymphocytes.
Authors: Pohajdak B , Gomez J , Orr F W , Khalil N , Talgoy M , Greenberg A H 
Published: December 2022

Abstract
The hypothesis that large granular lymphocytes (LGL) are capable of directed locomotion (chemotaxis) was tested. A population of LGL isolated from discontinuous Percoll gradients migrated along concentration gradients of N-formyl-methionyl-leucyl-phenylalanine (f-MLP), casein, and C5a, well known chemoattractants for polymorphonuclear leukocytes and monocytes, as well as interferon-beta and colony-stimulating factor. Interleukin 2, tuftsin, platelet-derived growth factor, and fibronectin were inactive. Migratory responses were greater in Percoll fractions with the highest lytic activity and HNK-1+ cells. The chemotactic response to f-MLP, casein, and C5a was always greater when the chemoattractant was present in greater concentration in the lower compartment of the Boyden chamber. Optimum chemotaxis was observed after a 1 hr incubation that made use of 12 micron nitrocellulose filters. LGL exhibited a high degree of nondirected locomotion when allowed to migrate for longer periods (greater than 2 hr), and when cultured in vitro for 24 to 72 hr in the presence or absence of IL 2 containing phytohemagluttinin-conditioned medium. The chemotactic LGL was HNK-1+, OKT11+ or HNK-1+, OKT11- on the basis of monoclonal antibody and complement depletion. They did not bear either T cell or monocyte cell surface markers, exhibiting an OKT3-, OKT4-, OKT8-, OKM1-, and MO2- phenotype, and did not form E rosettes at 29 degrees C, which is characteristic of lytic NK cells in contrast to T cells. Furthermore, a rat LGL leukemia (RNK) exhibited a chemotactic response to both f-MLP and casein. LGL chemotaxis to f-MLP could be inhibited in a dose-dependent manner by the inactive structural analog CBZ-phe-met, and the RNK tumor line specifically bound f-ML[3H]P, suggesting that LGL bear receptors for the chemotactic peptide.
Effect of selective T cell depletion of host and/or donor bone marrow on lymphopoietic repopulation, tolerance, and graft-vs-host disease in mixed allogeneic chimeras (B10 + B10.D2----B10).
Authors: Ildstad S T , Wren S M , Bluestone J A , Barbieri S A , Stephany D , Sachs D H 
Published: December 2022

Abstract
Reconstitution of lethally irradiated mice with a mixture of T cell-depleted syngeneic plus T cell-depleted allogeneic bone marrow (B10 + B10.D2----B10) leads to the induction of mixed lymphopoietic chimerism, excellent survivals, specific in vivo transplantation tolerance to subsequent donor strain skin grafts, and specific in vitro unresponsiveness to allogeneic donor lymphoid elements as assessed by mixed lymphocyte reaction (MLR) proliferative and cell-mediated lympholysis (CML) cytotoxicity assays. When B10 recipient mice received mixed marrow inocula in which the syngeneic component had not been T cell depleted, whether or not the allogeneic donor marrow was treated, they repopulated exclusively with host-type cells, promptly rejected donor-type skin allografts, and were reactive in vitro to the allogeneic donor by CML and MLR assays. In contrast, T cell depletion of the syngeneic component of the mixed marrow inocula resulted in specific acceptance of allogeneic donor strain skin grafts, whether or not the allogeneic bone marrow was T cell depleted. Such animals were specifically unreactive to allogeneic donor lymphoid elements in vitro by CML and MLR, but were reactive to third party. When both the syngeneic and allogeneic marrow were T cell depleted, variable percentages of host- and donor-type lymphoid elements were detected in the mixed reconstituted host. When only the syngeneic bone marrow was T cell depleted, animals repopulated exclusively with donor-type cells. Although these animals had detectable in vitro anti-host (B10) reactivity by CML and MLR and reconstituted as fully allogeneic chimeras, they exhibited excellent survival and had no in vivo evidence for graft-vs-host disease. In addition, experiments in which untreated donor spleen cells were added to the inocula in this last group suggest that the presence of T cell-depleted syngeneic bone marrow cells diminishes graft-vs-host disease and the mortality from it. This system may be helpful as a model for the study of alloresistance and for the identification of syngeneic cell phenotypes, which when present prevent engraftment of allogeneic marrow.
Biology of cloned cytotoxic T lymphocytes specific for lymphocytic choriomeningitis virus. V. Recognition is restricted to gene products encoded by the viral S RNA segment.
Authors: Riviere Y , Southern P J , Ahmed R , Oldstone M B 
Published: December 2022

Abstract
Lymphocytic choriomeningitis virus (LCMV) Armstrong (ARM) strain-specific, H-2d-restricted CTL effectively lyse syngeneic targets infected by LCMV ARM, but show reduced killing of LCMV Pasteur (PAST) strain-infected H-2d cells. We have reassorted the two RNA segments, large (L) and small (S), of LCMV ARM and PAST to generate LCMV with genotypes of L ARM/S PAST and L PAST/S ARM. By using these reassortants and both LCMV primary CTL and CTL clones, we report that the induction, recognition, and lysis of LCMV-specific CTL depend on the S RNA segment and the genes it encodes.
Expression of the common acute lymphoblastic leukemia antigen (CALLA) on the surface of individual cells of human lymphoblastoid lines.
Authors: Goldmacher V S , Lambert J M , Young A Y , Anderson J , Tinnel N L , Kornacki M , Ritz J , Blättler W A 
Published: December 2022

Abstract
Expression of the common acute lymphoblastic leukemia antigen (CALLA) on the surface of individual cells of the human lymphoblastoid lines CW678, Namalwa, and Nalm-6, and the distribution of the antigen epitopes within the cell populations have been determined quantitatively with the murine monoclonal anti-CALLA antibody J5. The distribution of CALLA epitopes in the cell populations was analyzed by indirect immunofluorescence measured by using flow cytometry. The average number of CALLA epitopes per cell were measured by two assays: in a direct assay by binding 125I-labeled antibody J5 to cells, and indirectly by binding 125I-labeled protein A from Staphylococcus aureus to J5-coated cells. On average, CW678, Namalwa, and Nalm-6 cells bore about 1 X 10(4), 6 X 10(4), and 8 X 10(4) CALLA epitopes per cell respectively. Histograms of the absolute number of CALLA epitopes expressed by individual cells in the populations of CW678, Namalwa, and Nalm-6 cultures were generated by a combined analysis of all the binding data. This is the first example of histograms showing quantitative distribution of antigen epitopes. Previously, the expression of antigens by individual cells as obtained by flow cytometry was only presented in terms of relative fluorescence intensity of individual cells in cell populations.
Stimulation of mouse lymphocytes by a mitogen derived from Mycoplasma arthritidis. IV. Murine T hybridoma cells exhibit differential accessory cell requirements for activation by M. arthritidis T cell mitogen, concanavalin A, or hen egg-white lysozyme.
Authors: Cole B C , Araneo B A , Sullivan G J 
Published: December 2022

Abstract
A T-cell mitogen present in culture supernatants of Mycoplasma arthritidis (MAS) is known to exhibit an absolute dependence on E alpha-bearing accessory cells (AC), which appear to function by binding the mitogen. We therefore compared the specificity and nature of the AC requirements for MAS and antigen-induced production of IL 2 in T hybridoma cell lines originating from a fusion by using hen egg-white lysozyme (HEL)-specific, H-2d-restricted T blasts. A marked specificity was noted in the ability of the hybridoma lines to become activated by Con A, MAS, or HEL antigen. Thus all three lines produced IL 2 in response to Con A without the addition of B lymphoma AC. Two lines responded to MAS, but only in the presence of AC, and only one line responded to HEL antigen in the presence of AC. Using the HEL responsive T hybridoma line, we demonstrated that disrupted AC and AC membranes could present MAS but not HEL. MAS rapidly associated with AC at 4 degrees C, whereas HEL failed to do so. Paraformaldehyde-fixed AC could absorb the mitogen in MAS and present it to T hybridoma cells within several minutes, whereas HEL antigen could only be presented by fixed AC if there was a prolonged period of incubation (greater than 30 min) at 37 degrees C before fixation. The combined data indicate that metabolically active cells are not required for the association of MAS with AC or for presentation of MAS to T hybridomas. In contrast, HEL antigen requires metabolically active cells for both of these processes. Thus, the mitogen in MAS can bind to AC without any processing requirements, and it is likely that the resulting complex of mitogen and Ia molecules can directly activate T hybridoma cells.
Interleukin 1 and the glomerular mesangium. I. Purification and characterization of a mesangial cell-derived autogrowth factor.
Authors: Lovett D H , Szamel M , Ryan J L , Sterzel R B , Gemsa D , Resch K 
Published: December 2022

Abstract
The proteins expressing interleukin 1 (IL 1) activity from rat peritoneal macrophages and cultured glomerular mesangial cells were compared after purification to apparent homogeneity. The purified IL 1 shared a number of biochemical features including m.w., charge, and specific activity. These findings were extended by the results of proteolytic peptide mapping, which revealed similar breakdown oligopeptides, confirming the close resemblance of these two IL 1 species produced by macrophages and mesangial cells. The purified mesangial cell IL 1 acts as an autocrine or paracrine growth factor. The local release of this cytokine may be an important factor in glomerular diseases characterized by mesangial proliferation and matrix expansion.
Development and characterization of antiserum to murine granulocyte-macrophage colony-stimulating factor.
Authors: Mochizuki D Y , Eisenman J R , Conlon P J , Park L S , Urdal D L 
Published: December 2022

Abstract
The expression in yeast of a cDNA clone encoding murine granulocyte-macrophage colony-stimulating factor (GM-CSF) has made possible the purification of large quantities of this recombinant protein. Rabbits immunized with pure recombinant GM-CSF generated antibodies that were shown to be specific for both recombinant GM-CSF and GM-CSF isolated from natural sources. Other lymphokines, including IL 1 beta, IL 2, IL 3, and recombinant human GM-CSF did not react with the antiserum. The antiserum, together with recombinant GM-CSF that had been radiolabeled with 125I to high specific activity, formed the foundation for a rapid, sensitive, and quantitative radioimmunoassay specific for murine GM-CSF. Furthermore, the antiserum was found to inhibit the biologic activities of GM-CSF as measured in both a bone marrow proliferation assay and a colony assay, and thus should prove to be a useful reagent for dissecting the complex growth factor activities involved in murine hematopoiesis.