bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transplantation in Miniature Swine
Authors: Lunney Joan K. , Sachs David H. 
Published: December 2022

Abstract
Immunochemical analyses of radioactively labeled lymphocyte antigens from miniature swine of three different homozygous major histocompatibility (MHC) types, AA, CC, and DD, have been performed. Anti-MHC sera were incubated with lentil lectin purified Nonidet P-40 swine lymphocyte extracts. Antigen-antibody complexes were then precipitated with protein A bearing staphylococci, eluted, and electrophoresed on sodium dodecyl sulfate polyacrylamide gels. Analysis of antigens from AA or DD cells revealed peaks of 42,000, 31,000, 25,000, and 11,000 dalton m.w. Platelet absorption of the anti-MHC sera yielded antibodies that only precipitated the intermediate m.w. molecules and lysed a subpopulation of swine peripheral blood lymphocytes, suggesting that these molecules were the miniature swine analogues of murine Ia antigens. Antibodies eluted from platelets lysed all lymphocyte populations and precipitated only the 42,000 and 11,000 dalton peaks, indicating that these molecules represent the analogue of murine H-2 histocompatibility antigens, containing a heavy chain and putative swine β2-microglobulin.
Immunofluorescent Detection of Human B Cell Alloantigens on S-Ig-Positive Lymphocytes and Epidermal Langerhans Cells
Authors: Stingl Georg , Katz Stephen I. , Abelson Leslie D. , Mann Dean L. 
Published: December 2022

Abstract
Several similarities exist between Langerhans cells (LC), a subpopulation of the mammalian epidermis, and cells of the monocyte-macrophage-histiocyte series, including the expression of common surface marker characteristics (Fc-IgG and C3 receptors). In further analogy, we asked the question of whether these cells also bear the human equivalent of murine and guinea pig Ia antigens, i.e., B cell alloantigens. Since LC constitute only 2 to 4% of isolated epidermal cells, cytotoxicity techniques did not seem feasible for this purpose. We therefore elaborated an indirect immunofluorescence (IF) technique for the detection of B cell alloantigens, using fluorescein-isothiocyanate-labeled staphylococcal protein A (FITC-SPA) as indicator reagent. Alloantisera were obtained from multiparous women of a highly inbred population. In simultaneous experiments we tested purified B cells from seven normal donors against a panel of alloantisera by a microcytotoxicity test and by IF. Data obtained showed that the alloantigens are selectively expressed on SIg-positive, but not on SIg-negative lymphocytes. Furthermore, there was an excellent agreement between both techniques (correlation coefficient: X2 = 31.09, p &lt;0.001). Isolated epidermal cells from those individuals whose B cells were tested for the expression of alloantigens were subjected to the IF procedure described above. None of the antisera which gave negative reactions on purified B cells of the respective individual reacted with its epidermal cells. By contrast, several of the antisera stained a small percentage of epidermal cells of those individuals whose B cells reacted with the very same antisera. By a simultaneously performed rosette assay with IgG-antibody-coated bovine red blood cells, it could be shown that the fluorescent and rosetted cell populations were identical, which means that—by IF techniques—LC are the only epidermal cells expressing B cell alloantigens.
Labeling Characteristics and Separation of Ia Antigen Subunits
Authors: Schwartz Benjamin D. , Vitetta Ellen S. , Cullen Susan E. 
Published: December 2022

Abstract
Experiments with biosynthetic incorporation of 3H-amino acids into murine and guinea pig Ia antigens have indicated that these antigens consist of two polypeptide chains of 33,000 and 25,000 daltons, respectively, occasionally linked by disulfide bonds into a 58,000 dalton molecule. In contrast, studies with lactoperoxidase-catalyzed radioiodination have indicated that these Ia antigens consist of only a single chain of 25,000 daltons. We therefore undertook a study to explore the basis of these discrepant results. Since 3H-tyrosine labeled both chains well, the lack of tyrosine residues in the 33,000 dalton chain could not be the explanation for the lack of radioiodination. However, by partially purifying the Ia antigen preparation with Lens culinaris (lentil) lectin affinity chromatography before immunoprecipitation and by increasing the resolution of analysis by using discontinuous-SDS polyacrylamide gel electrophoresis, it was possible to show that the 33,000 dalton chain was in fact radioiodinated, though still poorly so relative to the 25,000 dalton chain, and that a radioiodinated 58,000 dalton molecule could be detected. These experiments suggest that the 25,000 dalton chain is more exposed to the external cellular environment, and thus more readily iodinated by lactoperoxidase. In addition, the studies indicate that the choice of labeling method, purification procedures, and analytical methods must be taken into account when interpreting experimental results.
Glycolipid Markers of Murine Lymphocyte Subpopulations
Authors: Stein Kathryn E. , Schwarting Gerald A. , Marcus Donald M. 
Published: December 2022

Abstract
We have shown previously that purified antibodies to ganglioside GM1 react with peripheral T cells and most thymocytes in several strains of mice, independent of Thy-1 phenotype. GM1 and the Thy-1.2 antigen cap independently on C3H thymocytes, which provides additional evidence that GM1 is not the Thy-1.2 antigen. In C3H and nude mice antibodies to GM1 also react with a population of cells, comprising about 25% of lymphocytes from lymph nodes or spleen, that bear surface immunoglobulin. After removal of immunoglobulin from these cells by digestion with proteolytic enzyme, the GM1+ cells regenerate their surface immunoglobulin during 18 hr in culture, which indicates that these double-labeled cells synthesize their surface immunoglobulin. Protease treatment of lymphocytes reveals receptors for antibodies to GM1 on most cells. These data indicate that T and B cells differ in the accessibility of GM1 to antibody, and not necessarily in their content of GM1.
Purified antibodies to asialo GM1 react with mature T cells in all strains of mice tested. In contrast to anti-GM1, these antibodies do not react with most thymocytes, with immunoglobulin-bearing lymphocytes of C3H or nude mice, nor with pronase-treated B cells.
LPS-or 8Br-Cyclic AMP-Induced Production of T Cell-Activating Factor(s) in Macrophage Tumor Cell Line J774.1
Authors: Okada M. , Kishimoto T. , Igarashi T. , Teranishi T. , Yamamura Y. 
Published: December 2022

Abstract
The macrophage tumor cell line J774.1 replaced the function of normal macrophages in the induction of polyclonal killer T cells with 2-mercaptoethanol. J774.1 does not normally release soluble factor(s) which we have shown to be responsible for the differentiation of T cells to killer T cells. However, stimulation of J774.1 with LPS induced soluble factor(s) for T cell activation. An optimum concentration of LPS for the production of soluble factor(s) was 1 to 10 µg/ml, which completely inhibited growth of the tumor cells. The production of soluble factor(s) was observed within 6 hr after LPS stimulation and reached its maximum level at 24 hr. Incubation of the cell line with 8Br-cyclic AMP and theophylline induced soluble factor(s), suggesting that LPS stimulation induced an increase in intracellular cyclic AMP which leads to the synthesis of soluble factor(s).
Comparison of the Homogeneous, Primary Anti-Dextran B1355 Antibody Raised in BALB/c Mice with Protein 104E
Authors: Mayers G. L. , Bankert R. B. , Pressman D. 
Published: December 2022

Abstract
The primary antibody response to dextran B1355 in BALB/c mice is largely a homogenous IgM antibody. This antibody appears to be similar if not identical to the myeloma protein, protein 104E, for the following reasons: a) isoelectric focusing of the 7S monomers, separately and together in co-isoelectric focusing, give the same pattern, both in the presence and absence of 4M urea; b) the inhibition of lysis of the dextran-coated SRBC by specifically purified anti-dextran antibody and by protein 104E required essentially the same concentration of dextran B1355. This similarity was further demonstrated by plaque assays with dextran-coated SRBC, in which the formation of plaques was inhibited by free dextran. Inhibition of plaques produced by both types of cells required essentially the same concentration of dextran B1355. On these bases, there appears to be no difference in properties (or in structure) between the myeloma protein and the induced antibody.
The Effects of Phagocytosis, Dextran Sulfate, and Cell Damage on PGE1 Sensitivity and PGE1 Production of Macrophages
Authors: Gemsa Diethard , Seitz Michael , Kramer Wiebke , Till Gerd , Resch Klaus 
Published: December 2022

Abstract
During phagocytosis of zymosan or latex particles and after treatment with dextran sulfate, rat peritoneal macrophages responded to PGE1 by an elevated and prolonged production of cyclic AMP. Levels of cyclic AMP were not only augmented at the maximal effective concentrations of PGE1 but also at low, normally ineffective concentrations. Phagocytosis-induced enhancement of PGE1 sensitivity was proportional to the amount of interiorized particles, was independent of opsonizing factors, and did not occur in lymphocytes. In contrast, phagocytosis of silica particles or treatment with carrageenan caused a rapid loss of the response to PGE1, which was followed later by cell damage.
Synthesis and release of PGE1 was induced in macrophages by phagocytosis of zymosan but not of latex particles. Zymosan-induced PGE1 release was rather delayed and occurred at a high rate when the enhanced PGE1 sensitivity during phagocytosis had returned to near normal. Exposure of macrophages to silica particles or carrageenan also caused a high release of PGE1, however, it was associated with progressive enzyme leakage, which was used as a criterion for cell damage.
These observations suggest that phagocytosis-induced enhancement of PGE1 sensitivity combined with a subsequent release of PGE1 may be a sensitive control mechanism that may selectively regulate macrophage function under physiologic conditions. In contrast, the release of large amounts of PGE1 when associated with a loss of PGE1 sensitivity, may lead to an uncontrolled inflammatory response.
Virus-Induced Immune Complex Disease: Identification of Specific Viral Antigens and Antibodies Deposited in Complexes during Chronic Lymphocytic Choriomeningitis Virus Infection
Authors: Buchmeier Michael J. , Oldstone Michael B. A. 
Published: December 2022

Abstract
Structural proteins of LCMV were identified and their role in the immune complex glomerulonephritis of LCMV carrier mice was examined. Purified LCMV contained three major polypeptides, a single nonglycosylated nucleoprotein with an estimated m.w. of 63,000, and two surface glycoproteins of 54,000 and 35,000. Deposition of nucleoprotein antigen in the glomeruli of LCMV carrier mice of several strains was demonstrated by immunofluorescent staining with a monospecific antibody. In addition, Ig eluted from kidneys of three strains of LCMV carrier mice was shown by immune precipitation to react against all of major viral polypeptides of LCMV. Antibody from normal mice, and from mice with immune complex disease unrelated to LCMV did not show deposition of LCMV antigen in glomeruli, and Ig eluted from the kidneys of these mice did not react against LCMV antigens. Hence, mice infected at birth with LCMV and persistently infected throughout their life make antibodies to all the known structural polypeptides of the virus.
Depression of Mitogen Response in Spleen Cells from Reticuloendotheliosis Virus-Infected Chickens and Their Suppressive Effect on Normal Lymphocyte Response
Authors: Scofield Virginia L. , Bose Henry R. 
Published: December 2022

Abstract
Spleen cells and peripheral blood lymphocytes from chickens infected with reticuloendotheliosis virus (REV) were depressed in their responsiveness to phytohemagglutinin (PHA). When spleen cells from uninfected chickens were co-cultured with spleen cells from chickens infected with REV at 2 weeks of age, the PHA response by the normal cells was completely suppressed. Although spleen cells from chickens infected with REV at 6 or 9 weeks of age were also suppressed in their ability to respond to PHA, they did not suppress the mitogenic response of normal cells in mixed cultures.
Opinion
Authors: Benacerraf Baruj 
Published: December 2022

Abstract
Ever since the discovery of specific immune response (Ir) genes in the I regions of the major histocompatibility complex (MHC) of mammals (1), certain characteristic features of the phenomena they control presented a considerable challenge: H-linked Ir gene control has been observed only for thymus-dependent antigens that are proteins or polypeptides, and is concerned with T cell responses such as the stimulation of delayed-type hypersensitivity (DTH) and specific helper T cells (1, 2).The specificity of Ir gene function is remarkable and distinguishes readily between antigens with different amino acid primary sequences (3–6). This has been demonstrated for synthetic antigens and also for native antigens. It is nevertheless remarkably distinct from the specificity of the T cell responses themselves (7), a matter of considerable concern to me when we initially proposed that the Ir gene product could be the elusive T cell receptor (1).
The C5b-6 Complex: Formation, Isolation, and Inhibition of Its Activity by Lipoprotein and the S-Protein of Human Serum
Authors: Podack Eckhard R. , Kolb William P. , Müller-Eberhard Hans J. 
Published: December 2022

Abstract
C5b-6 complex was generated by activation of C7-depleted serum and purified 1200-fold based on its hemolytic activity. A homogeneous bimolecular complex with an s-rate of 11.5S and a m.w. of 328,000 daltons was obtained. The electrophoretic mobility was -3.4 × 10-5 cm2/volt sec. The subunit composition as revealed by SDS-polyacrylamide electrophoresis without reduction showed two protein bands: C5b (180,000) and C6 (120,000); and with reduction three subunits: C6 (128,000), C5bα (122,000), and C5β (75,000). Immunochemical analysis confirmed complex formation between C5b and C6 and showed the presence of one of the two neoantigens expressed by the SC5b-9 complex. Sixty nanograms of C5b-6 represented 108 hemolytically effective molecules. A hemolytic efficiency of 12 to 20 C5b-6 cell-bound complexes per lytic event was calculated from the uptake of radiolabeled C5b-6. The hemolytic efficiency of C5b-6 is dependent on the cell concentration.
C5b-6-initiated lysis is strongly inhibited by serum low density lipoproteins with an inhibition constant of Ki = 34 µg/ml and by the S-protein with Ki = 39 µg/ml. Lipoproteins and S-protein form a stable, hemolytically inactive complex with nascent C5b-7. The mechanism of C5b-7 inhibition is interpreted as a competition reaction between the target cell membrane and the inhibitors for the transitory binding site in nascent C5b-7.
Lipopolysaccharide Induction of IgM Antibodies to Polyadenylic Acid in Normal Mice
Authors: Fischbach Michael , Roubinian Jirayr R. , Talal Norman 
Published: December 2022

Abstract
Lipopolysaccharide (LPS) is able to induce autoantibodies reversibly in normal mice. Single or multiple doses of LPS induced a rapid and dose-dependent rise in antibodies to Poly A from 113 ng to 590 ng/ml serum as determined by Millipore filter radioimmunoassay. The response peaked at day 3 and was over by day 21. No response was seen if the LPS was chemically inactivated or injected into genetically nonresponsive mice. Antibodies were specific for Poly A and were not induced by T cell mitogens. Sucrose gradient ultracentrifugation demonstrated only IgM antibody. Neonatal thymectomy altered neither the immunoglobulin class nor quantity of antibody. Neonatal splenectomy did not affect antibody class but reduced the amount produced. No free Poly A could be detected in circulation after LPS stimulation. These findings suggest that normal mice have B lymphocytes capable of limited and reversible autoantibody production.
Binding and Activation of the First Component of Human Complement by the Lipid A Region of Lipopolysaccharides
Authors: Cooper Neil R. , Morrison David C. 
Published: December 2022

Abstract
A number of structurally different LPS preparations differing in content of lipid A and polysaccharide were examined for their ability to bind and activate the first component of human complement, C1. Lipid A-rich LPS preparations as well as isolated lipid A were found to be orders of magnitude more active in binding highly purified precursor C1 as well as C1 than polysaccharide-rich preparations. This interaction was shown to occur through the C1q portion of the C1 macromolecule. Attachment of the lipid A-rich LPS preparations to C1 is a biologically meaningful event as it was demonstrated to lead to activation of proenzyme C1 reconstituted from highly purified C1q and proenzymes C1r and C1s. Further, an unusual dose response profile was obtained for the lipid A-rich LPS preparation from Salmonella minnesota R 595 in that relatively high doses of LPS bound C1 but activation was inhibited. Lower doses, in contrast, bound and also activated C1. Isolated lipid A, by comparison, bound and activated C1 efficiently at high and low dose ranges.
The lipid A region of the LPS molecule was found to be responsible for classical pathway activation. This conclusion derives from several observations. First, isolated lipid A was more active in binding and activating C1 and LPS containing even minor proportions of carbohydrate. Second, polymyxin B, an antibiotic that binds to the lipid A portion of LPS, abrogated the C1-activating ability of the preparations. Third, the presence of LAP, a protein that is associated with lipid A in certain LPS preparations, interfered with C1 binding by LPS. Finally, alteration of lipid A by mild alkaline hydrolysis abrogated its C1-binding capacity. These studies thus show, in a purified system, that the lipid A region of lipid A-rich LPS preparations isolated from rough strains of bacteria can directly and efficiently activate the classical pathway at the C1 step. This reaction proceeds in the absence of antibody. Thus, in this system C1q fulfills a recognition role normally associated with the antibody molecule.
Lymphocytes in the Rabbit Expressing Receptors for the Fc Portion of Rabbit Immunoglobulin
Authors: Birch Ruth E. , Bernier George M. , Fanger Michael W. 
Published: December 2022

Abstract
Nonspecies-specific receptors for the Fc portion of immunoglobulin (RFc) were detected in various rabbit lymphoid tissues by the ability of the RFc-bearing cells to form rosettes with ox red blood cells coated with the IgG fraction of a rabbit antiserum directed against ox red blood cell stroma. The rosette assay was shown to be specific for Fc receptor activity. In lymphocyte preparations containing less than 5% phagocytic cells the average percent of RFc-bearing lymphocytes in the various tissues was as follows: appendix 12%, lymph node 9%, peripheral blood 26%, spleen 31%, and thymus 0%. In double assay experiments, in which the lymphocytes were prestained with an FITC-labeled goat anti-rabbit Fab IgG fraction before rosetting, the RFc-bearing lymphocytes were found to constitute a subpopulation of the surface Ig (sIg)-bearing cells in the tissues examined when normal nonactivated rabbit lymphocytes were studied. After Pronase treatment, under conditions sufficient to remove cell surface Ig, and subsequent incubation to allow resynthesis of sIg, the percentage of sIg-bearing cells was restored to pretreatment levels. Conversely, although the Pronase treatment initially had no effect on RFc, there was a decline in detectable RFc-bearing cells after incubation in both treated and untreated preparations. Even with the loss of RFc+ lymphocytes during the incubation period, the percentage of sIg+ lymphocytes that expressed RFcγ remained fairly constant, suggesting the existence of an RFc+-sIg- subpopulation in the rabbit. Double assays employing FITC-labeled goat anti-rabbit antibody specific for µ and γ determinants were performed to determine if there was any relationship between the class of sIg expressed and the presence of Fc receptor. There was an overlap in IgM- and IgG-bearing lymphocytes, but no apparent overlap between IgM+ RFcγ+ and IgG+ RFcγ+ lymphocytes, suggesting that cells expressing both surface IgM IgG do not possess RFcγ. In the present study cells with receptors for the Fc portion of IgM were not detected in any of the tissues examined under the conditions employed.
Adherent Cell Function in Murine T Lymphocyte Antigen Recognition
Authors: Rosenwasser Lanny J. , Rosenthal Alan S. 
Published: December 2022

Abstract
The data in this report describe a T cell proliferation assay with nylon wool column-purified murine lymph node lymphocytes from animals immunized by footpad injection of antigen in CFA. It was found that the in vitro immune response of sensitized T cells to soluble protein antigens was functionally dependent on the presence of adherent cells, more specifically macrophages, at all concentrations of in vitro antigen challenge. The response was due to T cells in that cytotoxic treatment of the immune lymphocyte cells with anti-Thy 1.2 serum and complement effectively eliminated the antigen-specific DNA synthetic responses. The antigen-specific proliferation of murine lymphocytes depleted of adherent cells could not be reconstituted with either guinea pig macrophages nor murine fibroblasts, indicating the existence of species and cell type specificity. In contrast to previous observations in the guinea pig, soluble products of cultured adherent cells could at least partially replace the function of intact macrophages in the response to antigen.
On the Mechanism of Membrane Damage by Complement: The Effect of Length and Unsaturation of the Acyl Chains in Liposomal Bilayers and the Effect of Cholesterol Concentration in Sheep Erythrocyte and Liposomal Membranes
Authors: Shin Moon L. , Paznekas William A. , Mayer Manfred M. 
Published: December 2022

Abstract
As shown previously, the action of activated complement (C) on a lipid bilayer produces two distinct effects, namely, formation of transmembrane channels and transfer of phospholipid from the bilayer to the aqueous phase. In the present work, we show that both phenomena are affected by the structure of the membrane lipids. Increasing acyl chain length of lecithin liposomes containing cholesterol was found to decrease release of 86Rb+ by antibody (Ab) and C or by purified C5b,6 + C7 + C8 + C9. These changes in 86Rb+ release suggest that channel formation is affected by membrane thickness. Similarly, release of 14C-PC by Ab + C diminished with increasing acyl chain length.
Release of 86Rb+ from egg lecithin liposomes by Ab + C was found to diminish with increasing cholesterol concentration. On the other hand, higher release of 14C-PC was observed with increasing cholesterol concentration. Cholesterol itself was not released by Ab + C.
The effect of membrane cholesterol was also studied with sheep erythrocytes by incubation of the cells with a cholesterol-enriched medium. In accord with the results obtained with liposomes, the susceptibility of erythrocytes to hemolysis by C5b-9 was found to diminish with increasing cholesterol enrichment of the membrane, which indicates that cholesterol affects channel formation.
The effect of unsaturation was tested by treatment of C18:0 or C18:1 lecithin liposomes containing 43% molar cholesterol with Ab + C. 86Rb+ release was decreased, whereas 14C-PC release was slightly increased when unsaturated chains were present. Membrane fluidity is not believed to be the sole controlling factor since the changes in this parameter by varying cholesterol or by unsaturation did not correlate with the effects on marker release.