bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural characterization of human melanoma-associated antigen p97 with monoclonal antibodies.
Authors: Brown J P , Nishiyama K , Hellström I , Hellström K E 
Published: December 2022

Abstract
Monoclonal antibodies were used to study p97, a human melanoma-associated antigen (MAA). Four hybridomas, designated 4.1, 96.5, 118.1, and 8.2, were obtained by fusing mouse myeloma cells with spleen cells from mice immunized with human melanoma cells. Antibodies 4.1 and 8.2 were IgG1; antibodies 96.5 and 118.1 were IgG2a. Sequential immunoprecipitation (IP) and sodium-dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that all 4 antibodies recognized the same 97 kilodalton (kD) protein. Binding studies with 125I-labeled antibody showed that antibodies 4.1 and 96.5 bound the same epitope, p97a. Antibodies 118.1 and 8.2 defined epitopes p97b and p97c, respectively. Six monoclonal antibodies (M17, L1, L10, R10, I12, and K5) specific for gp95, a kD melanoma cell surface glycoprotein were also tested. Sequential IP showed that these antibodies bound p97; p97 and gp95 are thus identical. Binding studies showed that antibody m17 bound epitope p971, and antibodies L1, L10, and R19 bound epitope p97c. Antibodies I12 and K5 defined 2 other epitopes, p97d and p97e, respectively. SDS-PAGE under nonreducing conditions indicated that p97 is monomeric, probably with intrachain disulfide bonds. Cell-surface labeling of sialic acid residues and neuraminidase digestion showed that p97 is a sialoglycoprotein. Digestion of p97 with papain or trypsin produced a stable 40 kD fragment, which expressed epitopes p971, p97b, and p97c, but not p97d or p97e.
Stimulation of oxidative metabolism in murine polymorphonuclear leukocytes by unopsonized fungal cells: evidence for a mannose-specific mechanism.
Authors: Danley D L , Hilger A E 
Published: December 2022

Abstract
Murine polymorphonuclear leukocytes (PMN) are stimulated to produce hydrogen peroxide (H2O2) by some unopsonized fungi, including Coccidioides immitis spherules, Candida albicans blastospores, and Saccharomyces sp. blastospores (zymosan). In this communication we have examined the basis for this stimulation by studying the effects of mannan and its primary constituent, D-mannose, on PMN function in vitro, since this polysaccharide is a significant component in many fungal cell walls. Our results show that mannan stimulated H2O2 production and iodination by PMN and enhanced H2O2 production by cells stimulated with zymosan. Moreover, the amount of H2O2 released by PMN was directly related to the concentration of mannan, and mannan obtained commercially or prepared in our laboratory worked equally well. Mannose, on the other hand, inhibited H2O2 release from PMN stimulated with zymosan or mannan and reduced oxygen consumption, carbon dioxide production, superoxide release, and iodination by these cells as well. With respect to specificity of inhibition, 18 different monosaccharides were examined by using 2 different assays for H2O2 release; and only 2-deoxy-D-glucose, a potent glycolytic inhibitor, reduced H2O2 release from zymosan-stimulated PMN. Furthermore, H2O2 release from cells stimulated with phorbol myristate acetate or opsonized Sephadex was not inhibited by mannose whereas H2O2 release was reduced when PMN were stimulated with C. albicans blastospores or C. immitis spherules in the presence of this sugar. From these data we propose that initiation of PMN oxidative metabolic burst in response to some unopsonized fungi occurs through a mannose-specific mechanism.
Lymphocyte transformation and the number of antigen-responsive cells in humans.
Authors: Sohnle P G , Collins-Lech C 
Published: December 2022

Abstract
The lymphocyte transformation response of normal human subjects to the antigen streptokinase/streptodornase (SK/SD) was analyzed by quantitating antigen-responsive cells (ARC), estimating the first generation lymphocyte response (FGLR), and performing standard lymphocyte transformation assays at different time points. Unlike the results obtained with the nonspecific mitogen phytohemagglutinin (PHA), the response to SK/SD appeared to depend almost entirely on the participation of progeny lymphocytes derived from a small number (mean of 21.3 +/- 5.8 per 100,000 mononuclear cells) of cells initially sensitive to the antigen. Similar peak lymphocyte transformation responses were obtained for the 2 stimuli, although those to SK/SD occurred later. Lymphocyte transformation data obtained after a shorter than optimal culture period (6 days) appeared to be a better estimate of ARC than the data obtained at the peak of the response of ARC than the data obtained at the peak of the responses did. However, ARC were best estimated by determining the FGLR or the number of days required for the lymphocyte transformation response to reach its peak.
Increased Fc receptor activity in monocytes from patients with rheumatoid arthritis: a study of monocyte binding and catabolism of soluble aggregates of IgG in vitro.
Authors: Katayama S , Chia D , Nasu H , Knutson D W 
Published: December 2022

Abstract
We studied the binding and catabolic function of adherent monocytes from patients with rheumatoid arthritis (RA) and normal subjects using stable, heat aggregates of IgG125I (A-IgG) as a model for soluble immune complexes. Scatchard plots of 4 degrees C binding data showed that RA monocytes had increased binding avidity and higher maximal binding capacity for A-IgG compared with monocytes from normal subjects. These data suggest that RA monocytes have increased numbers of Fc receptors for IgG, although a concomitant increase in the avidity of individual Fc receptors could not be excluded. At 37 degrees C, RA monocytes; kinetic analysis suggested that increases in catabolized A-IgG were due to increased binding of A-IgG with no change in the fractional rates of catabolism. Latex titers of RA patients correlated with the number of Fc receptors detected on RA monocytes. Mononuclear phagocytes from RA patients are often exposed to endogenous immune complexes that may be present in the blood of such patients; immune complexes may stimulate monocytes and possibly other mononuclear phagocytes to increase their capacity to bind and catabolize soluble immune complexes.
Genetic factors controlling the susceptibility to experimental autoimmune thyroiditis in inbred rat strains.
Authors: Lillehoj H S , Beisel K , Rose N R 
Published: December 2022

Abstract
CDF (high responder) rats were crossed with SHR (low responder) rats to study genetic factors influencing susceptibility to experimental autoimmune thyroiditis (EAT). F1 hybrid rats showed intermediate susceptibility to thyroiditis. Gene segregation patterns of F2 and backcross rats demonstrated that the immune response to rat thyroglobulin (RaTg) is under polygenic control. A main factor controlling immune response to RaTg is associated with the X chromosome. Females of CDF and SHR rats produced higher levels of antibody, suggesting that antibody production to RaTg is a sex-influenced trait. Different genetic control mechanisms are evident in autoantibody production and thyroid lesions. No evidence of linkage of an immune response gene to RaTg to the major histocompatibility complex of the rat (RT1) was observed.
Growth of 17D yellow fever virus in a macrophage-like cell line, U937: role of Fc and viral receptors in antibody-mediated infection.
Authors: Schlesinger J J , Brandriss M W 
Published: December 2022

Abstract
Growth characteristics of 17D yellow fever virus (17D-YF) and conditions for infection were studied in U937, a macrophage-like, Fc receptor-bearing continuous human cell line. Antibody to 17D-YF was obtained by immunization of normal subjects with 17D-YF vaccine. Cells were infected in the presence or absence of immune whole sera or immunoglobulin fractions. Infection of U937 was temperature dependent; the yield of virus was variable but at low temperature viral titers were consistently higher when infection was established in the presence of antibody. Results of infectious center assays indicated that the increased yield of virus was largely or entirely due to an increase in the number of cells producing virus early in the course of infection. Enhancement of viral growth was mediated by IgG but not IgM fractions of immune sera. Trypsinization of U937 resulted in a 90 to 95% reduction of infection in the absence of antibody but in the presence of antibody viral titers were higher in trypsinized than in nontrypsinized cells. Antibody to 17D-YF, contained in the whole IgG fraction of sera, bound to U937 to mediate infection without first being complexed to virus. Preincubation of U937 with IgG1 but not IgG2 myeloma proteins abrogated antibody-mediated infection. This result is compatible with the known affinities of U937 Fc receptors for specific subclasses of IgG and provides evidence for the role of the Fc receptor in antibody-mediated enhancement of viral growth. Persistent infection characterized by a lack of detectable cytopathogenic effect was established in long-term cultures of U937. This pattern of infection might be related to the unique effectiveness of the 17D-YF vaccine.
Macrophage production of fibronectin, a chemoattractant for fibroblasts.
Authors: Tsukamoto Y , Helsel W E , Wahl S M 
Published: December 2022

Abstract
Activation of macrophages results in the production of numerous enzymes and effector molecules. One of these monokines released by macrophages can cause directed migration of connective tissue fibroblasts in vitro. Production of this macrophage-derived chemotactic factor for fibroblasts requires activation of the macrophages either in vivo or in vitro and de novo protein synthesis. The chemotactic activity in the macrophage supernatants could be removed by a fibronectin-specific affinity column and was inhibited in the presence of antibodies to fibronectin. Furthermore, chemotactic activity in the depleted macrophage supernatants could be restored by the addition of exogenous fibronectin. Fibronectin was identified in activated macrophage supernatants by an enzyme-linked immunoassay for fibronectin. From these findings it was concluded that activated macrophages release a chemoattractant for fibroblasts and that the primary chemoattractant molecule is fibronectin. The production of fibronectin by activated macrophages may thus serve as an inflammatory mediator that in addition to its other functions can recruit fibroblasts to an area of damaged tissue, where they can proliferate and form the scar tissue necessary for tissue repair. Furthermore, in chronic inflammation, the prolonged activation of macrophages may be related to the extensive fibroblast infiltration and fibrosis that can accompany these lesions.
Endogenous retroviral envelope antigen in plasma cells.
Authors: Halpern M S , Ewert D L , Flores L J , Lin K Y , England J M 
Published: December 2022

Abstract
Previous observations that endogenous retroviral envelope antigen is expressed in splenic Ig(+) B cells of SRBC-sensitized 15I5 X 71 chickens suggested that expression of this antigen might be a general property of plasma cells in 15I5 and related strains. To investigate this possibility, immunofluorescence assays with antiviral sera were carried out using plasma cells present in Harder glands. Endogenous retroviral envelope antigen was detectable in plasma cells of line 15I5 X 71, 15I5 X 72, and 15I5 chickens but not in plasma cells of line 72, 15B, or 63 chickens. Higher levels of retroviral envelope antigen were detectable in 15I5 X 71 plasma cells as compared to 15I5 X 71 bursal cells. The presence of retroviral envelope antigen in 15I5 plasma cells, coupled with the absence of detectable levels of retroviral p27-related antigen in these cells, suggested that expression of the former is governed by the ev 6 genetic locus.
The role of adherent HLA-DR+ mononuclear cells in autologous and allogeneic MLR.
Authors: Huber C , Fink U , Leibold W , Schmalzl F , Peterson P A , Klareskog L , Braunsteiner H 
Published: December 2022

Abstract
The aim of this study was to define the significance of HLA-DR+ cells for the in vitro induction of human autoreactive T cell proliferation. Proliferation was induced by autologous or allogeneic non-T cells or EB virus-transformed LCL. Pretreatment of stimulator cells with low concentrations of RAHLA-DR and C and with high amounts of RAHLA-DR alone abolished the capacity to stimulate autologous or allogeneic T cells. This suggested that antigens associated with HLA-DR+ stimulator cells or HLA-DR itself are involved in the induction of this proliferation. At the responder cell level the cytotoxic elimination of HLA-DR+ cells as well as depletion of adherent cells by passage through Sephadex G-10 columns reduced both autoreactive and alloreactive responsiveness. Responses of serologically and physically depleted populations were both restored by reconstitution with mitomycin-C treated autologous adherent cells. These cells were resistant to lysis with T cell specific antibodies and preferentially cooperated with T cells of autologous deprivation. Co-cultivation experiments further revealed that such accessory cells were capable of amplifying T cell proliferation in the presence of suboptimal numbers of autologous LCL. We concluded, therefore, that an HLA-DR+-adherent cell, presumably of monocytic origin, is required for optimal proliferative responsiveness of both autoreactive and alloreactive T cells.
Immunochemistry of groups A, B, and C meningococcal polysaccharide-tetanus toxoid conjugates.
Authors: Jennings H J , Lugowski C 
Published: December 2022

Abstract
The successful coupling of the meningococcal groups A, B, and C polysaccharides to tetanus toxoid to yield water soluble conjugates is described. Reactive aldehyde groups were strategically introduced into the terminal residues of the polysaccharides by the controlled periodate oxidation of the native groups B and C polysaccharides and of the group A polysaccharide previously modified by the reduction of its terminal reducing N-acetyl-mannosamine residue. This produced essentially monovalent polysaccharide molecules, which were subsequently covalently linked to tetanus toxoid by means of reductive amination. Although the groups A and C polysaccharides proved to be poor immunogens in rabbits and mice, their tetanus toxoid conjugates produced high levels of polysaccharide-specific antibodies in both animals. By contrast, even in the form of its tetanus toxoid conjugate, the group B polysaccharide failed to elicit homologous polysaccharide-specific antibodies in either animal; a major proportion of the antibodies actually produced had a specificity for the linkage area of the conjugate. This evidence is compatible with the hypothesis of the poor immunogenicity of the group B polysaccharide being structure related. Hyperimmunization of mice with the groups A and C polysaccharide-tetanus toxoid conjugates produced antisera with good bactericidal activity against their respective homologous organisms, and indicated the potential of these conjugates as potential human vaccines.
Most B cells that have switched surface immunoglobulin isotypes generate clones of cells that do not secrete IgM.
Authors: Gearhart P J , Cebra J J 
Published: December 2022

Abstract
The order of genes coding for the constant regions of immunoglobulin heavy chains is 5'-C mu, C delta, C gamma 3, C gamma 1, C gamma 2b, C gamma 2a, C epsilon, C alpha-3'. To try to determine whether switching of the expression of heavy chain genes is irreversible and occurs in a direction from 5' to 3' within a cell line, we have isolated B cells bearing particular membrane isotypes, stimulated them to generate clones, and assayed daughter cells for secreted antibody. B cell with and without surface IgM and IgD, and B cells with and without surface IgG, were isolated by fluorescence-activated cell sorting. Fractionated cells were individually stimulated with phosphorylcholine in a splenic fragment assay, and the antibody secreted by clonal progeny was assayed for several heavy chain isotypes by radioimmunoassay. The results show that 1) B cells bearing IgM and IgD can produce individual clones of cells secreting 3 isotypes of anti-phosphorylcholine antibody--IgM, IgG, and IgA; 2) most B cells expressing surface IgG generate clones that secrete IgG but not IgM; and 3) most B cells from gut-associated lymphoid tissue that do not express surface IgM or IgD generate clones of cells that secrete IgA but not IgM. Therefore, IgM- and IgD-bearing cells can give rise to progeny that secrete IgM, IgG, and IgA. Once B cells switch to a different surface isotype, they appear restricted in isotype potential, since they frequently generate clones of cells that do not secrete IgM. These findings suggest that isotype switching is generally irreversible, and isotypes are expressed in a 5'- to -3' direction that is consistent with the germline gene order.
Studies on immunopathogenesis in epidemic hemorrhagic fever: sequential observations on activation of the first complement component in sera from patients with epidemic hemorrhagic fever.
Authors: Yan D , Gu X , Wang D , Yang S 
Published: December 2022

Abstract
Sequential measurements of activation of the 1st component of complement (C1) in the sera of 29 patients hospitalized with epidemic hemorrhagic fever (EHF) were performed according to a method recently developed. These patients were treated with supportive, routine therapy, but not immunosuppressive agents. This paper describes the kinetic observations on the activation of C1 in the 29 cases. The data confirm that an apparently increased extent of activation occurred in their sera. It was found that the more severely ill the patients were, the more apparent the activation. Additionally, beginning with the 15th day of disease, the extent of C1 activation diminished in most of the moderate and severe types of patients, but not in those with moribund illness and fatal ones. On the basis of the study, it may be reasonably concluded that C1 activation was correlated well with the severity and clinical course of EHF, indicating that the classical C pathway was activated in these patients. We feel that our findings are important to an understanding and elucidation of the immunopathogenetic mechanisms of EHF.
The attack phase of human complement: differentiation between membrane binding and complex formation by the detection of neoantigen expression in situ. A morphometric immunoferritin study.
Authors: Balkarowa-Ständer J , Rother U , Rauterberg E W 
Published: December 2022

Abstract
C5-9 neoantigen was found by morphometric immunoferritin staining on the membrane of guinea pig erythrocytes lyzed by reactive lysis C5b6 or acid-activated C5 + C6 and C7, C8, and C9. Neoantigen first appeared at the C7 step, increasing with C8, and decreasing after the addition of C9. The incubation of E with C5-C8 or C5-C9 at 0 degrees C resulted in EC5-8 without neoantigen. Reincubation of these cells after washing at 37 degrees C for 5 min led to neoantigen expression. An energy-requiring step is postulated after binding of C5-C8 and needed for C9 binding and lysis.
Unique T cell Ia antigen expressed on a hybrid cell line producing antigen-specific augmenting T cell factor.
Authors: Hiramatsu K , Miyatani S , Kim M , Yamada S , Okumura K , Tada T 
Published: December 2022

Abstract
Hybrid cell lines were established by fusion between keyhole limpet hemocyanin(KLH) binding T cells of A/J mice and an AKR T cell tumor line, BW5147. Hybrids were selected for the presence of Ia antigen and KLH-specific augmenting activity of their extracts in the secondary antibody response. The detailed phenotypic and functional analysis of 1 of these clones, FL10, is reported here. The hybrid was positive for both Thy1.1 and Thy1.2 antigens and possessed the Lyt-1+,2-,3- phenotype. Both VH and Ia determinants were detected on their cell surface. The IA locus was mapped in the I-A subregion, but the Ia specificities were serologically distinct from those of B cell Ia antigen. This was demonstrated by the fact that anti-Ia antiserum preabsorbed with B cells could react with the hybrid cells, whereas none of the monoclonal anti-Ia specific for private and public determinations of Iak could. The extract from the cell line specifically augmented the in vitro secondary antibody response against dinitrophenylated KLH, and this activity was removed by absorption with antigen and conventional anti-Ia antisera. The results indicate that the cell line, FL10, carries Ia antigen unique to the T cell, which is associated with the antigen-specific augmenting molecule.
The effects of ultraviolet irradiation on the generation of anti-tumor cytotoxic effector cell responses in vitro.
Authors: Lynch D H , Gurish M F , Daynes R A 
Published: December 2022

Abstract
The effects of irradiation of lymphoid cells in vitro with ultraviolet (UV) light were studied using radiation sources that are widely used both in the study of photocarcinogeneic mechanisms and by commercial tanning parlors (FS40 sunlamps). Low doses of direct exposure of cells was found to abrogate the differentiation events that lead to the generation of functional cytotoxic T lymphocytes (CTL). UV irradiation of cells in vitro induces alterations that, although not immediately obvious, lead to cell death during the next several days in tissue culture. Energy titration experiments demonstrated that both primed T cells and accessory cells were sensitive to the effects of direct UV-exposure; T cells were found to be much more sensitive than accessory cells. A 90% decrease in CTL generation could be affected with as little as 10 sec of UV exposure. These effects appear to be caused by wavelengths in the UVB range (280 to 320 nm), since exposure of cells to much higher doses of energy in the UVA range (320 to 400 nm) were not inhibitory. The spectrum of wavelengths in the UV region is large (200 to 400 nm). The data presented here demonstrate that it is overly simplistic to assume that all wavelengths in the UV spectrum mediate their effects via identical mechanisms. Furthermore, the wavelengths at which a given amount of energy is emitted appears to be much more important than the absolute amount of energy (in joules) which biologic systems are subjected.
Human IgE antibody synthesis in vitro: stimulation of IgE responses by pokeweed mitogen and selective inhibition of such responses by human suppressive factor of allergy (SFA).
Authors: Zuraw B L , Nonaka M , O'Hair C , Katz D H 
Published: December 2022

Abstract
The studies presented herein provide details of an in vitro system in which IgE biosynthesis by human peripheral mononuclear cells can be stimulated by exposure to pokeweed mitogen (PWM). Mononuclear cells of normal donors or patients with hyperimmunoglobulinemia E were cultured in 2 stages, the first stage consisting of exposure of cells to stimulating mitogen; after this first stage incubation, cells were washed and replated in cultures devoid of any additional mitogen for a further 6 days. Under such conditions, human mononuclear cells were shown to synthesize significant quantities of IgE. Both T cells and surface IgE-bearing cells were shown to be necessary in order to obtain an IgE response in this system. Supernatants from 2-way human mixed lymphocyte cultures were shown to contain an IgE class-specific suppressive factor capable of selectively inhibiting in vitro IgE (and not IgG) biosynthesis. This model can be used to compare the regulation of IgE synthesis in normal and atopic donors, and further experiments examining the production and action of this class-specific suppressive factor may have prognostic and therapeutic implications.