bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies of a high molecular weight human melanoma-associated antigen.
Authors: Hellström I , Garrigues H J , Cabasco L , Mosely G H , Brown J P , Hellström K E 
Published: December 2022

Abstract
Hybridomas were generated by fusing SP2/0 mouse myeloma cells with spleen cells from mice that had been immunized with cultured human melanoma cells. One of the hybridomas secreted a monoclonal IgG1 antibody, 48.7, which binds to a cell surface antigen of cells from human melanomas and compound nevi. The presence of the target antigen in vivo was demonstrated immunohistologically by staining frozen sections of primary and metastatic melanoma by the peroxidase anti-peroxidase technique. Weak staining of some blood vessel cells was also seen, but other normal cells, including skin melanocytes, were unstained, as were cells from other tumor types. Antibody 48.7 immunoprecipitated polypeptides with apparent m.w. on sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 250,000 and greater than 400,000.
Cross-reactivity of suppressor T cells specific for lactate dehydrogenase B and IgG2a myeloma protein.
Authors: Nagy Z A , Baxevanis C N , Klein J 
Published: December 2022

Abstract
The major histocompatibility complex-controlled immune responsiveness of mice to two unrelated antigens, lactate dehydrogenase B (LDHB) and IgG2a myeloma protein is remarkably similar (1, 2). The similarity is explained by our recent work, demonstrating that both antigens, when presented in the context of cell surface Ek (Ek alpha Ek beta) molecules, generate strong suppression that causes nonresponsiveness to all mouse strains expressing this molecule. The suppression is mediated by antigen-specific, Ek-restricted Lyt-1+2+ suppressor T (Ts) cells, which act by inhibiting the proliferation of A(A alpha A beta)-restricted, Lyt-1+2- (possibly T helper [Th]) cells specific for the same antigen (3-5). However, the question of why the Ek molecule, in combination with two structurally unrelated proteins, preferentially induces Ts cells has remained unanswered. We demonstrate here that the anti-LDHB and anti-IgG2a Ts cells are fully cross-reactive, which indicates that the LDHB + Ek and IgG2a + Ek determinants recognized by these cells are very similar or identical.
Expression of Ia antigen on epidermal keratinocytes after the grafting of normal skin to nude mice.
Authors: Daynes R A , Emam M , Krueger G G , Roberts L K 
Published: December 2022

Abstract
During the course of experimentation designed to evaluate the migration of host Langerhans cells (LC) into normal skin grafted onto nude mice, we observed that the epidermal cells of these grafts were induced to express la determinants solely of graft origin. The data presented herein indicate that the expression of la by normal epidermal cells correlates with the infiltration of host LC into the graft. This la expression is restricted to the keratinocytes within the epidermis of the grafted skin, is first observed 7 to 9 days post-grafting, and persists within the grafted skin for greater than 12 wk. The induction of la expression by keratinocytes appears to be the result of the environment that is provided by the nude mouse host and is independent of both passenger lymphocytes within the skin graft and allogeneic differences between graft and host. We strongly believe that these studies provide the basis for the development of an experimental animal model system for investigating the potential role that la expression by epidermal cells may play in enhancing the immune response to antigens encountered in the skin.
Monoclonal anti-Lyt-2 antibodies block the activation of cytolytic T lymphocyte precursors.
Authors: Glasebrook A L , MacDonald H R 
Published: December 2022

Abstract
In the present study, we reinvestigated the effects of anti-Lyt-2 monoclonal antibodies (mAb) on the generation of H-2K/D-specific Lyt-2+ cytolytic T lymphocytes (CTL). A sensitive limiting dilution microculture system supplemented with a source of interleukin 2 (IL 2) was employed to provide a minimal estimation of the frequency of CTL precursors (CTL-P) in normal spleen or mixed leukocyte culture (MLC) populations. The addition of anti-Lyt-2 (but not anti-Thy-1) mAb at culture initiation caused an average 78% reduction in the number of CTL-P within spleen cell populations that were activated by allogeneic stimulation. Most CTL that were generated from Lyt-2+ CTL-P in the presence of anti-Lyt-2 mAb were not inhibited in cytolysis by such mAb, whereas the majority of CTL generated in the absence of anti-Lyt-2 were inhibitable. In contrast to normal spleen, the frequency of (operationally defined) CTL-P that had been activated for 5 days in primary MLC was unaffected by the presence of anti-Lyt-2 mAb. Collectively, these results demonstrate that anti-Lyt-2 mAb are capable of inhibiting the antigen-dependent activation of normal splenic precursors of Lyt-2+ CTL. The fact that IL 2 could not overcome the inhibition suggests that anti-Lyt-2 mAb may have affected the expression of IL 2 receptors as a direct consequence of inhibiting CTL-P antigen recognition.
Suppression of lymphocyte proliferative responses: demonstration of two stages occurring in the in vitro generation of suppressor macrophages.
Authors: Stout R D , Fisher M 
Published: December 2022

Abstract
The suppressor macrophages generated by in vitro culture of spleen cells are shown to be derived from nonadherent splenic precursors. The induction of suppressor macrophage generation requires the presence of both plastic-adherent and plastic-nonadherent spleen cells during the first 24 to 48 hr of culture. After this induction period, the primed nonadherent cells can continue to generate suppressor macrophages through several serial transfers. The primed nonadherent spleen cell population is predominantly comprised of cFcR+ cells (40 to 50%) and Thy-1+ cells (40%), many of which appear to be undergoing blastogenesis. The generation of suppressor macrophages appears to proceed in two stages. The first stage is radiosensitive and has a minimum duration of 1 to 2 days. Although this stage initially coincides with the inductive period, it is also required for the continuous propagation of the suppressor macrophages upon serial transfer of the nonadherent spleen cells. The second stage is radioresistant and has a maximum duration of 2 to 3 days. The in vitro events thus bear similarities to events occurring during in vivo differentiation and activation of effector macrophages. It is suggested that the in vitro generation of suppressor macrophages may be one component of syngeneic mixed lymphocyte responses when spleen cells are used as the responding population, and that the suppressors represent part of a regulatory system controlling lymphocyte and macrophage differentiation and activation.
Treatment of autoimmune MRL/Ipr mice with monoclonal antibody to Thy-1.2: a single injection has sustained effects on lymphoproliferation and renal disease.
Authors: Seaman W E , Wofsy D , Greenspan J S , Ledbetter J A 
Published: December 2022

Abstract
MRL/Mp-lpr/lpr (MRL/lpr) mice spontaneously develop an autoimmune disease characterized by anti-DNA antibodies, immune-complex glomerulonephritis, and massive proliferation of a distinct population of T cells. The proliferating T cells have the phenotype Thy-1.2+, T200+, Lyt-1+,2-,3-, but Thy-1.2 and Lyt-1 are expressed in abnormally low density. These cells appear to function as helper cells, and neonatal thymectomy prevents both lymphoproliferation and autoimmunity, which suggests that autoimmunity in MRL/lpr mice is secondary to T cell proliferation. We therefore attempted to reduce lymphoproliferation by treating MRL/lpr mice with a single injection of rat monoclonal antibody (MAb) to Thy-1.2 (30-H12, IgG2b). Mice were treated at 8 wk, before the onset of overt disease. We found that MRL/lpr mice were resistant to depletion of circulating T cells (CTC) by anti-Thy-1.2; 0.6 mg of antibody totally depleted CTC from normal mice, but had little or no effect on CTC in MRL/lpr mice. However, treatment with 6 mg of MAb against Thy-1.2 reduced CTC in MRL/lpr mice by over 70%. Moreover, this single treatment markedly reduced the proliferation of CTC over the ensuing 3 mo, despite clearance of the anti-Thy-1.2 from the circulation within 3 wk. Treated mice maintained better renal function than untreated controls, as assessed by levels of blood urea nitrogen (BUN), although anti-DNA antibodies were not significantly reduced. The effect of anti-Thy-1.2 was specific; treatment with rat MAb to the common leukocyte antigen T200 produced only a transient effect on circulating lymphocytes and did not reduce renal disease. The prolonged effects of a single injection of anti-Thy-1.2 suggest that the MAb produces a sustained alteration in immune regulation. The improvement in renal disease is in accord with evidence that autoimmune disease in MRL/lpr mice is T cell dependent. Monoclonal anti-lymphocyte antibodies may be useful in the treatment of autoimmunity.
Effects of aging on cell cooperation and lymphocyte responsiveness to cytokines.
Authors: Rosenberg J S , Gilman S C , Feldman J D 
Published: December 2022

Abstract
Functional activities and cell cooperation of macrophages (Mphi), T cells, and B cells of young and old Lewis rats were compared. Splenic M phi from young and old rats provided accessory help for T cell mitogenesis and B cell mitogenesis, provided accessory help for generation of PFC, and produced IL 1 equally well as measured in costimulator assays. Splenic T cells of aged Lewis rats, however, were poorly responsive in mitogen assays and did not respond to supplemental IL 2 and antigen with blast transformation and with increased help for B cells to produce PFC. "Old" B cells did not respond in vitro to mitogens with help from M phi and T cells, nor did they respond to B cell helper factor with increased PFC. The data indicate that hyporesponsiveness of the immune system, especially of B cells, in aged rats is due in part to defective reactivity to interleukins and cytokine(s) and to defective cell-cell cooperation.
Lymphokine regulation of activated (G1) lymphocytes. I. Prostaglandin E2-induced inhibition of interleukin 2 production.
Authors: Walker C , Kristensen F , Bettens F , deWeck A L 
Published: December 2022

Abstract
PGE2-induced inhibition of the proliferatory response of PHA-stimulated human PBL and Con A-stimulated murine thymocytes was analyzed by flow cytometry. It was found that the activation process (G0-G1a transition) was not influenced by PGE2 over a wide range of concentrations (10(-10) to 10(-6) M), nor was the formation of IL 2 receptors inhibited. Similarly, the viability of human lymphocytes was practically unaltered. In contrast, the IL 2-dependent cell cycle event (G1a-G1b transition), which is required for proliferation, was inhibited in a dose-dependent fashion. The addition of IL 2-containing supernatants to such cultures prevented the PGE2-mediated block in the G1a phase and reconstituted a normal lymphocyte proliferation. Furthermore, lower IL 2 titers were measured in supernatants from PHA-stimulated human PBL treated with PGE2. These findings strongly suggest that PGE2 primarily exerts its inhibitory effect on lymphocyte proliferation through an inhibition of IL 2 production.
Cross-reactive idiotypic determinants on antibodies and antigen-specific helper T cell continuous lines.
Authors: Lifshitz R , Apte R N , Mozes E 
Published: December 2022

Abstract
Anti-idiotypic antibodies produced in C57BL/6 mice (H-2b, Igh-1b) against (T,G)-A--L-specific antibodies of C3H.SW mice (H-2b, Igh-1j) were used to probe (T,G)-A--L-specific helper T cell lines and clones for the expression of idiotypic determinants on the cell surface of the monoclonal functional T cells. By using the fluorescence-activated cell sorter (FACS II), anti-idiotypic sera of individual mice that specifically bind C3H.SW anti-(T,G)-A--L antibodies were shown to stain significantly cells of the E-9M(+) continuous T helper line originated from C3H.SW (T,G)-A--L "educated" T cells. The same antisera did not react with a helper T cell line of C3H.SW origin specific to human gamma-globulin. They also did not stain a (T,G)-A--L-specific helper T cell line derived from CWB (H-2b, Igh-1b) mice, which differ from C3H.SW mice only in their heavy chain allotypes. Thus, the expression of the idiotypic determinants on the T cell lines appears to be antigen-specific and linked to the heavy chain allotypic marker as shown for the specific antibodies. Different clones derived from the E-9 M(+) line were tested their reactivity with the individual anti-idiotypic sera. All clones but one (1.11) were stained significantly. The clones were tested for their biologic activity and all of them except clone 1.11 were found to exert helper activity specific to (T,G)-A--L. Thus, individual anti-idiotypic sera against C3H.SW anti-(T,G)-A--L antibodies recognize cross-reactive idiotypic structures on the surface of antigen-specific monoclonal helper T cells.
Biosynthesis of glycosaminoglycans by epithelial and lymphocytic components of murine thymus.
Authors: Britz J S , Hart G W 
Published: December 2022

Abstract
Interactions between the epithelial and lymphocytic components of the thymus are required for T cell maturation, yet the molecular bases for these interactions remain elusive. In the development and function of other endodermally derived organs, glycosaminoglycan-containing proteins are known to play a critical role. In contrast, virtually nothing is known about the macromolecules that are major constituents of thymic interstitial spaces. For these reasons, we undertook metabolic labeling studies in vitro with D-(6-3H)glucosamine and 35SO4(-2) to begin to characterize systematically the relative amounts and types of glycosaminoglycans made by enriched subpopulations of cells within the thymus. Hydrocortisone, which depletes the thymus of 90% of its lymphocytes, was used both to enrich for epithelium-derived glycoconjugates and to determine if significant alterations in glycoconjugate metabolism accompany drug-induced premature thymic involution. Results indicate: 1) glycosaminoglycans account for a substantial proportion of the total glycoconjugates synthesized by both thymocytes and epithelium; 2) Glycosaminoglycans show a tissue-specific distribution. Hyaluronic acid is the major glycosaminoglycan synthesized by thymic epithelium, whereas it accounts for less than 15% of the total glycosaminoglycans made by thymocytes; 3) Similar proportions of sulfated glycosaminoglycans are made by thymic epithelium and thymocytes. Chondroitin sulfates predominate (75 to 90%) over heparan sulfates (10 to 25%). Chondroitin sulfates from both nonstimulated thymocytes and epithelium are nearly exclusively sulfated at the 4-position of their N-acetylgalactosamine residues; 4) The major high m.w. glycoconjugate of thymocytes, however, is nonsulfated and is resistant to pronase, hyaluronidase, chondroitinase ABC, nitrous acid, keratanase, and neuraminidase; 5) Although hydrocortisone treatment causes a dramatic inhibitory effect on the incorporation of radioactivity into smaller oligosaccharide side-chains by "cortisone-resistant" thymocytes, the drug exerts negligible effects on the metabolism of glycoconjugates by epithelium. These data, which quantify and categorize the complex arrays of glycoconjugates synthesized by the major cell types of the thymus, establish the necessary foundations for further investigations into the functional roles of these glycoconjugates in thymic epithelium-induced maturation of T lymphocytes.
SFR3-DR5, a monoclonal antibody with HLA-DR5 specificity.
Authors: Radka S F , Machamer C , Cresswell P , Kostyu D D , Ward F E , Amos D B 
Published: December 2022

Abstract
We have developed a monoclonal antibody with HLA-DR5 serologic specificity. The antibody, SFR3-DR5, binds specifically to DR5-positive lymphoblastoid cell lines, and immunoprecipitates alpha- and beta-chains characteristic of DR antigens from them. Cytotoxic activity of the antibody segregates with the DR5-bearing haplotype in a family. The antibody reacted with the cells of 16 of 17 DR5 individuals and was negative on all DR5-negative cells tested. SFR3-DR5 reacted weakly with PWM-activated cells of the single DR5 individual whose B lymphocytes were unreactive with the monoclonal antibody by cytotoxicity. Possible interpretations of these results are discussed.
Salmonellae activate complement differentially via the alternative pathway depending on the structure of their lipopolysaccharide O-antigen.
Authors: Liang-Takasaki C J , Grossman N , Leive L 
Published: December 2022

Abstract
Differences in the O-antigen polysaccharide structure of lipopolysaccharide were previously shown to affect the rate of phagocytosis of Salmonellae strains by the murine macrophage-like cell line J774. Phagocytosis required a serum factor(s) that is labile to heat (56 degrees C for 30 min) and to zymosan treatment, which indirectly suggested the participation of C. We now show, using guinea pig serum, that these bacteria activate C3 at different rates, and this activation is proportional to the later rate of phagocytosis. Activation is predominantly via the alternative pathway, because C4 is not consumed and the reaction proceeds equally well in the serum of C4-deficient guinea pigs. Because the extent of activation of C3 and the subsequent rate of phagocytosis are inversely proportional to virulence, we propose that virulence of a strain may be influenced by the ability of the polysaccharide structure of its lipopolysaccharide to activate the alternative pathway of C, destining it for subsequent phagocytosis.
Functional properties of membrane-associated complement receptor CR1.
Authors: Iida K , Nussenzweig V 
Published: December 2022

Abstract
It was previously shown that membrane receptors for C3b (CR1) purified from human erythrocytes were powerful inhibitors of the complement cascade and that they encompass the regulatory functions of the serum proteins beta 1H (H) and C4-binding protein (C4bp). In the present report we study the functional properties of membrane-associated CR1. When tonsil lymphocytes, which contain between 30 and 60% of CR1-bearing B cells, are incubated with the red cell complement intermediate EAC14oxy2lim or EAC14oxy23lim, they inhibit both C42 and C423 in a dose-dependent manner. These effects are mediated by membrane-associated molecules. Indeed, mild trypsinization of the lymphocytes abolishes their activity, and formaldehyde-fixed cells are as effective as viable cells. The inhibitory effects are in part mediated by CR1. The lymphocyte activities are reversed about 60% if monoclonal antibodies to CR1 or fluid phase C3b are present in the incubation medium. Moreover, upon addition of C3b-inactivator (l), lymphocytes release C3c fragments from EAC14oxy23b. The release of C3c was also abolished by antibodies to CR1. These results support the idea that CR1, as well as other molecules from the lymphocyte membrane, can function as inhibitor(s) of complement activation in their vicinity.
The biologic activity of mast cell granules. IV. The effect of complement depletion on rat cutaneous late phase reactions.
Authors: Lemanske R F , Joiner K , Kaliner M 
Published: December 2022

Abstract
Cutaneous late phase reactions (LPR) in rats can be induced by the intradermal injection of anti-IgE antibody or isolated rat peritoneal mast cell granules. Rat LPR are characterized by neutrophil-rich infiltrates at 2 to 8 hr followed by mononuclear cell-rich infiltrates thereafter. Rat Arthus reactions are histologically similar and are complement (C) dependent. To determine the importance of C in the pathogenesis of rat LPR compared with its role in Arthus reactions, rats were treated with cobra venom factor (CVF) (250 U/kg i.v.), and the effects of this treatment on total hemolytic complement (CH50), C3 titers, LPR, and Arthus reactions were assessed. CVF treatment produced profound decreases in both CH50 (from 197 +/- 20 to less than 1.0 U/ml) and C3 (from 44,240 +/- 2840 to less than 5 U/ml) titers after 6 hr, which persisted through at least 30 hr. The inflammatory intensity of heterologous reverse passive Arthus reactions was significantly decreased in CVF-treated animals. In contrast, the intensity of LPR was unaffected by CVF treatment. Therefore, although LPR and Arthus reactions share certain histologic characteristics, these similarities are not due to a mutual requirement for the presence of C.
IgE-mediated release of histamine from human cutaneous mast cells.
Authors: Tharp M D , Suvunrungsi R T , Sullivan T J 
Published: December 2022

Abstract
We investigated the ability of antigen-IgE interactions to stimulate histamine release from human infant cutaneous mast cells. Skin obtained at circumcision contained numerous perivascular mast cells, as assessed by light and electron microscopy. The histamine content of this tissue averaged 17.7 ng (+/- 1.5 SEM)/mg wet weight. Challenge of 200-microns thick sections of unsensitized skin with varying concentrations of monoclonal murine antibodies to human IgE caused no net release of histamine. After skin sections were incubated in the presence of 5 micrograms/ml of human myeloma IgE (S) for 120 min at 37 degrees C, monoclonal anti-IgE challenge resulted in 40.1% (+/- 6.0 SEM) histamine release. Similar passive sensitization with 1/20 dilutions of serum from humans expressing IgE to purified Juniperus sabinoides (JS) antigen rendered the tissue responsive to specific antigen challenge. Dose-related histamine release occurred over 30 min with optimal release of 12.6% (+/- 2.4 SEM) after stimulation with 100 ng/ml of JS antigen. This reaction required sensitization with serum containing IgE to JS and was antigen-specific. Optimal reactions to antigen occurred at 3 mM added Ca++, 34 degrees C to 37 degrees C, pH 7.2. Antigen-induced release was markedly influenced by the added Ca++ concentration; no release occurred in the absence of Ca++, 54% of the optimal response was observed at 2 mM Ca++, and 28% of the optimal response occurred at 4 mM Ca++. The addition of Mg++ did not influence antigen-induced release. The results of this study provide functional evidence that 1) human infant cutaneous mast cells express Fc-epsilon receptors; 2) these receptors are largely unoccupied in vivo; and 3) stimulation of passively sensitized infant mast cells with anti-IgE or specific antigen leads to immediate histamine release. This new system should permit detailed in vitro studies of immediate hypersensitivity reactions in human skin.
Role of lipomodulin, a phospholipase inhibitory protein, in immunoregulation by thymocytes.
Authors: Hirata F , Iwata M 
Published: December 2022

Abstract
The treatment of murine thymocytes with anti-lipomodulin antibody during Con A stimulation causes selective loss of suppressor activity, but not of helper activity on PFC assay, when co-cultured with T cell-depleted spleen cells. Interaction of the antibody with responder cells in thymocyte culture were necessary in the early stage rather than in the later stage of lymphocyte activation by Con A, which suggests that anti-lipomodulin antibody acts in the stage of suppressor T cells generation. When thymocytes were cultured with purified lipomodulin for 48 hr, suppressor activity was induced. Lipomodulin as detected by radioimmunoassay was found to be released from T cells with the phenotype of I-J+, Lyt-1-, Lyt-2+. The immunoprecipitates from the media of Con A-stimulated thymocyte with anti-I-Kk antibody and anti-lipomodulin antibody were analyzed on SDS-gel electrophoresis. I-J products had m.w. 36,000 and 24,000, whereas lipomodulin had m.w. 36,000, 24,000, and 15,000. Because anti-I-Jk antibody could precipitate 125I-labeled lipomodulin purified from rabbit neutrophils, these results suggest that lipomodulin is a product of I-J genes that induces suppressor T cells.