bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Role of Humoral Factors in the Initiation of in Vitro Primary Immune Responses
Authors: Watson James , Epstein Ruth 
Published: December 2022

Abstract
Mouse spleen cells cultured in medium containing deficient fetal bovine serum (deficient medium) do not support primary immune responses to heterologous erythrocyte antigens. A factor, here termed deficient serum restoring factor (DSRF), has been isolated which stimulates primary immune responses in spleen cells cultured in deficient medium. DSRF alone does not stimulate DNA synthesis in mouse spleen cultures. It is required along with the immunogen in the period before the onset of DNA synthesis in the activation of precursors of antibody-forming cells. Deficient medium supports the induction of secondary immune responses by spleen cells which have been primed with antigen in vivo. DSRF does not substitute for thymus-derived cells, adherent cells or allogeneic lymphocytes in the initiation of in vitro immune responses. Unless precursor antibody-forming cells are exposed to DSRF they are not susceptible to the inductive stimulus in deficient medium. The in vitro system utilizing deficient medium appears to distinguish between virgin and experienced precursor antibody-forming cells, and offers a new way of identifying the role of humoral factors in the differentiation of antibody-forming cells.
Binding of 125I-Labeled Anti-IgG, Rheumatoid Factor and Anti-C3 to Immune Complexes on the Surface of Virus-Infected Cells
Authors: Hayashi Kozaburo , Lodmell Donald , Rosenthal Joel , Notkins Abner Louis 
Published: December 2022

Abstract
Recently, we reported that 125I-labeled antiviral antibody could be used to detect newly synthesized viral antigens on the surface of infected cells (1). The present report describes an indirect radioimmunoassay for detecting viral antigens and antiviral antibody and demonstrates that rheumatoid factor and complement can bind to immune complexes on the surface of infected cells.
Primary rabbit kidney cells (PRK)1 were prepared and maintained as described previously (2) in tissue culture trays containing 24 wells, each 16 mm in diameter (Bellco Glass, Inc., Vineland, N. J.). Herpes simplex virus (HSV), type 1, and vaccinia virus (CVI-79) were grown and assayed in PRK cells (2, 3). Antiserums to HSV and vaccinia were prepared in rabbits and the 50% neutralization titers were approximately 1:2000 (4). Normal rabbit serum was obtained from unimmunized rabbits. Pooled human serum, used as a source of anti-vaccinia antibody, had a 50% neutralization titer of 1:80.
Studies on the Mechanism of Lymphocyte-Mediated Cytolysis
Authors: Henney Christopher S. 
Published: December 2022

Abstract
The lysis of DBA/2 mastocytoma cells by splenic lymphocytes from C57BL mice obtained 10 days after alloantigenic stimulation has been investigated by following the release of various target cell markers. Although the events initiating the cytolytic pathway occurred very rapidly, the rupture of the cell membranes took place some considerable time later, following a period of gradual, progressive increases in permeability. Thus, when the efflux of low molecular weight indicators (e.g., ATP, 86Rb) from target cells was measured, increases in membrane permeability could be demonstrated within 20 min of the addition of sensitized lymphocytes. Target cell indicators which became associated with intracellular components, however, (51Cr, 3H-thymidine-DNA) could not be demonstrated extracellularly unless considerably longer periods of incubation were used. The rate of appearance of these indicators was inversely related to their effective molecular size.
Although the rate of efflux of different indicators varied considerably, the number of effector lymphocytes necessary to initiate specific release was comparable, and events leading to release of label were in all cases similar. Thus, all indicators were released in a linear manner both as a function of time and as a function of the number of effector cells present. Similarly, in the absence of divalent cations, none of the indicators were specifically released.
Measurement of the ATP released after incubation of cytolytically active lymphocytes with target cells indicated that both interacting cell types undergo membrane permeability changes as the result of their interactions, although in the case of the lymphocyte this increase was apparently of a nonprogressive nature.
A Human IgG Myeloma Protein with Anti-α2 Macroglobulin Antibody Activity
Authors: Seligmann Maxime , Sassy Catherine , Chevalier Annette 
Published: December 2022

Abstract
A human IgG 1 κ myeloma protein which specifically precipitates with α2 macroglobulin (α2 M) from horse, rabbit and pig is described. This protein did not combine with human α2 M nor with α2 M from various other species. The binding activity was exclusively located in the Fab regions of the molecule. Quantitative studies showed that this protein gave a flocculation type of precipitin curve with horse α2 M and that rabbit α2 M behaved as a cross-reacting antigen. This patient had received two injections of horse antitetanus serum in 1930 and 1936. That the antibody specificity of this myeloma protein was related to an extrinsic source of antigenic stimulation is emphasized.
Induction of Reagin Synthesis in the Rat with Associated and Dissociated Hemocyanin: Effect of Antilymphocyte Serum
Authors: White G. J. , Holm M. S. 
Published: December 2022

Abstract
Dissimilar reagin synthesis patterns were observed in Bordetella pertussis-treated rats which were immunized with equivalent amounts of associated or dissociated keyhole limpet hemocyanin (KLH). The associated form induced low titers of reagin in about 50% of the animals which peaked 30 days post-immunization. The dissociated form induced higher titers in 75% of the animals which peaked 10 days post-immunization. In contrast, the associated form of KLH was a more potent antigen than the dissociated form in the production of KLH agglutinins. Administration of equine antilymphocyte serum (ALS) to rats before or after immunization produced an alteration in the reagin synthesis pattern which was dependent on the time of ALS treatment. If given before immunization, early synthesis was enhanced. If given after immunization, late synthesis was enhanced. ALS treatment was suppressive for KLH agglutinin production, particularly with dissociated KLH immunized animals. The dissimilar antibody response to different forms of the same antigen, coupled with the exquisite dependence of early reagin synthesis on time of administration of ALS, leads to the speculation that macrophages may control an early event which determines reagin response.
Functional Heterogeneity of Murine Lymphoid Cells
Authors: Stobo John D. , Paul William E. 
Published: December 2022

Abstract
The mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) stimulate only those mouse lymphocytes which have undergone differentiation within the thymus and thus bear the differentiation antigen θ. However, not all thymus-derived lymphocytes (T cells) react equally to both mitogens, and the differential responsiveness of T cells to PHA and Con A may be used to indicate the existence of T cell subsets. One subpopulation of T cells exists which demonstrates approximately equal reactivity to both mitogens and bears a relatively high density of θ determinants. Another subpopulation exists which responds mainly to Con A, and bears a relatively reduced density of θ determinants. T cell subsets so delineated also differ in their recirculation patterns, radiation sensitivities, location in peripheral lymphoid tissue, and most importantly, in their function. These differential characteristics may represent the capabilities of T cells in various stages of differentiation within one T cell line. On the other hand, these cells may be representative of two distinct T cell lines and preliminary evidence consistent with this possibility is presented.
Studies in Myasthenia Gravis: Active Antigenic Sites Related to Humoral Antibody Induction
Authors: Rule Allyn H. , Bartlett Patricia , Osserman Kermit E. 
Published: December 2022

Abstract
Purification of human muscle proteins by 0.5 M KCl extraction, differential solubility and centrifugation produced fractions which reacted with human myasthenic sera. Absorption with either actomyosin or myosin removed all activity shown by the indirect immunofluorescent assay. Quantitative complement fixation showed that active fractions included the initial crude preparations, highly purified actomyosin and myosin. Actin preparations had no antigenic activity. Myosin contained at least 50 times more activity than actomyosin in both the complement fixation and the absorption studies. These data suggest that myosin contains the antigenic sites related to humoral antibody induction in myasthenia gravis.
A Solid Phase Radioimmunoassay for the Quantitation of Human Reaginic Antibody against Ragweed Antigen E
Authors: Zeiss C. Raymond , Pruzansky J. J. , Patterson Roy , Roberts Mary 
Published: December 2022

Abstract
IgE antibody directed against antigen E (AgE) of ragweed extract was measured quantitatively in the sera of 15 ragweed sensitive patients before initiation of immunotherapy. The assay employed polystyrene tubes which were successively coated with myeloma IgE and excess rabbit anti-IgE. This matrix which was specific for IgE bound IgE from the patients' serum in a reproducible and measurable manner. Radiolabeled AgE then reacted quantitatively with IgE antibody from the patients' serum which was attached to the solid phase. A double antibody method was developed simultaneously and gave comparable results for sera assayed by both procedures. Total serum IgE and the dose response of histamine release by AgE from washed leukocytes of the patients were also determined.
The concentration of IgE anti-AgE in the 15 sera ranged from 3.2 to 400 ng/ml by polystyrene tube assay. Serum IgE ranged from 82 ng to 6 µg/ml and the percentage of the serum IgE specific for AgE varied from 0.3 to 41. Leukocyte sensitivity measured by the reciprocal of the minimum concentration of AgE resulting in release of 50% of the total histamine encompassed a 300-fold range.
The level of IgE antibody to AgE was not correlated significantly with total serum IgE. Cell sensitivity varied independently of total serum IgE or nonspecific IgE. A highly significant correlation was found between IgE anti-AgE and cell sensitivity. Leukocyte sensitivity was found to be an exponential function of the serum antibody concentration.
Suppression of the in Vitro Anamnestic Response of Rabbit Lymph Node Cells by Anti-IgG Serum
Authors: Herscowitz Herbert B. 
Published: December 2022

Abstract
Treatment of previously primed rabbit popliteal lymph node cell suspensions with specific, absorbed anti-IgG serum resulted in significant suppression of the in vitro anamnestic response to keyhole limpet hemocyanin (KLH). Anti-IgM treatment did not interfere with antibody formation. The degree of suppression observed was dependent on the amount of anti-IgG added to the cultures. High dilutions of anti-IgG consistently enhanced antibody synthesis. Maximum suppression was achieved when the anti-IgG was added within the first 12 hr after culture initiation. For effective suppression, the anti-IgG had to be in the cultures for up to 48 hr. Suppression could be reversed by the addition of purified rabbit IgG to the cultures, but not by an excess of KLH. Although anti-IgG was cytotoxic in the presence of complement, this does not appear to be the mechanism of action. The results suggest that cells involved in the anamnestic response to KLH bear a surface receptor which is a reflection of the immunoglobulin product ultimately synthesized.
The Fate of Anti-Ig-Surface Ig Complexes on B Lymphocytes
Authors: Engers Howard D. , Unanue Emil R. 
Published: December 2022

Abstract
The fate of 125I-rabbit IgG anti-mouse immunoglobulin complexed to the surface-bound immunoglobulin of B lymphocytes was investigated. Each immunoglobulin-bearing B lymphocyte bound an average of 160,000 molecules of antibody to immunoglobulin under saturating conditions. These preparations of B lymphocytes had been previously depleted in their content of non-lymphoid cells. The B lymphocytes were placed in culture and the fate of the 125I-anti-Ig was determined. Early during culture a small amount of anti-Ig sedimenting heavier than IgG was released into the culture supernatants. Most of the remaining Ig was catabolized. Examinations of culture and cell supernatants identified the 125I bound to amino acids or to smaller protein fragments. This metabolism of the anti-immunoglobulin molecules was temperature-dependent and also specific for that fraction of the rabbit IgG capable of interacting with the surface immunoglobulin present on B lymphocytes. We conclude that the B lymphocyte sheds a small percentage of the immune complex and internalizes and effectively degrades the remainder.
Migration Inhibitory Effect of Cell-Free Supernatants from Tuberculin-Stimulated Cultures of Human Mononuclear Leukocytes Demonstrated by Two-Step Mif Agarose Assay
Authors: Clausen Jens Erik 
Published: December 2022

Abstract
Agarose gel technique with human peripheral blood leukocytes as migrating indicator cells was used to demonstrate migration inhibition factor (MIF) in cell-free supernatants from cultures of tuberculin-stimulated human peripheral blood mononuclear leukocytes. In this two-step MIF agarose assay only a few hundred microliters of supernatant were used. MIF was produced if cells from Mantoux-positive persons were cultured with purified protein derivative of tuberculin (PPD), but also if the sensitive cells after preincubation with PPD were washed and cultured in medium without PPD. There was a good correlation between the migration inhibitory effect of supernatants from PPD-stimulated cultures and the Mantoux reaction. The two-step MIF agarose assay was more sensitive than the direct leukocyte migration agarose test and makes possible the testing of several pairs of supernatants and a standard of MIF activity on the same migrating indicator cell population.
Immunologic Tolerance in C4 Deficient Guinea Pigs
Authors: Cohen Benjamin E. , Green Ira , Davie Joseph M. 
Published: December 2022

Abstract
The precise mechanisms by which immunologic tolerance is induced have not as yet been elucidated. There are a variety of different types of tolerance (1–3) and tolerance in both thymus-derived lymphocytes (T lymphocytes)2 and bone marrow-derived lymphocytes (B lymphocytes) has been described (4).
Tolerance induction may involve the destruction of specific immuno-competent cells upon contact with antigen. Support for this concept comes from the finding by some investigators that the number of antigen-binding cells, which appear to be precursors of antibody-secreting cells, are reduced in tolerant animals (5, 6). One possible mechanism for tolerance induction is that antigen, upon reacting with cell surface-bound immunoglobulin receptors, may under certain conditions activate complement at the surface of the cell and thus cause destruction of these cells. Azar et al., following this line of reasoning, have produced a transient complement deficiency in mice with a variety of agents and have reported that in such temporarily complement deficient animals tolerance is more difficult to achieve than in normal animals (7–9).
Effect of Specific Antibody on the Antigen-Induced Proliferative Response of Rabbit Lymph Node Cells
Authors: Thorbecke G. J. , Siskind G. W. 
Published: December 2022

Abstract
High concentrations of antibody specifically inhibited the proliferative response of sensitized rabbit lymph node cells to antigen. In contrast, low concentrations of antibody, in the presence of a heat labile component of fresh serum, markedly augmented the antigen-stimulated uptake of thymidine by sensitized lymph node cells.
Effect of Blocking the Active Site of an Antibody on the Expression of Its Idiotypic Determinants during Immunization
Authors: Spring-Stewart Susan , Nisonoff Alfred 
Published: December 2022

Abstract
Antiidiotypic antibodies were elicited in rabbits by immunization with soluble complexes consisting of anti-p-azobenzoate antibody and excess (RGG)-p-azobenzoate. Nearly all of the antiidiotypic antisera, in contrast to such antisera formed in response to free antibenzoate antibody, were not inhibitable by haptens, i.e., by benzoate derivatives of low molecular weight. The results indicate that when the active site is blocked during immunization, antiidiotypic antibodies are directed exclusively to determinants outside the active site. The antigen, RGG-p-azobenzoate, evidently is not removed from the antibenzoate antibody before the recognition process in the recipient animal. The immunogenicity of soluble complexes is lower than that of the free antibody, as indicated by the relatively smaller percentages of donor antibody precipitable by antiidiotypic antisera. This also was attributed to blocking of an important idiotypic determinant.
The Effect of Antibody on Antigen-Induced Lymphocyte Transformation
Authors: Banks Keith L. 
Published: December 2022

Abstract
The influence of antibody on the antigen-induced in vitro uptake of tritiated thymidine by sensitive lymphocytes was determined. The cellular response of ovalbumin (OA)-sensitive lymphocytes was consistently depressed when OA was mixed with anti-OA antisera at concentrations equal to equivalence and 2 times antigen excess with one antiserum and 50 times antibody excess with another antiserum. At five other concentrations of these antisera, involving either antigen excess or antibody excess, the reaction of animals varied between depression and augmentation. Similar increases and decreases in stimulation occurred with cells sensitive to sheep RBC (SRBC) when the antigen was in the presence of anti-SRBC antiserum. Non-sensitive cells were not stimulated by immune complexes formed with OA or SRBC. Depressive complexes did not affect cell viability or response to phytohemagglutinin. Complexes composed of non-sensitizing antigen did not influence stimulation by another antigen to which the cells were sensitive. Depression also occurred when antibody was added to cultures composed of at least 97% lymphocytes. The experiments show that the in vitro response of sensitive lymphocytes may be specifically depressed or augmented by antibody.
A Rabbit Anti-p-Azobenzenearsonate Antibody of Restricted Heterogeneity with Light Chains of b5 Allotype
Authors: Mage Rose G. , Appella Ettore , Young-Cooper Glendowlyn O. , Winfield John B. , Pincus Jack H. , Chersi Alberto 
Published: December 2022

Abstract
A rabbit, partially suppressed for the expression of b5-kappa-type light chains when first immunized, produced anti-p-azobenzenearsonate antibodies at 8, 13, 34 and 41 months of age, after each of four courses of immunization with an edestin-azobenzenearsonate conjugate. The antisera obtained after the second, third and fourth courses of immunization contained antibodies of limited structural heterogeneity. Light chains of b5 allotype were obtained from the purified antibodies. Amino acid sequence analysis of the first 21 residues at the amino terminus of the light chains indicated a single sequence for those from the third course antibody and a major sequence with limited heterogeneity from the second and fourth course antibodies.
The Antibody Response to Polyinosinic · Polycytidylic Acid
Authors: Parker Leroy M. , Steinberg Alfred D. 
Published: December 2022

Abstract
The antibody response to the synthetic double-stranded RNA polyinosinic·polycytidylic acid (rI·rC) was investigated in mice and rabbits. Mice developed an early, largely IgM, antibody response of short duration after a single injection of rI·rC in aqueous solution. The magnitude of this response was unaffected by complexing rI·rC to a protein carrier. Relative tolerance rather than increased amounts of antibody followed subsequent injections of rI·rC. However, there was a shift in antibody class to IgG. When rI·rC was given in Freund's adjuvant prolonged IgG antibody responses occurred with peaks appearing 2 or more weeks after immunization. Administration of rI·rC complexed to an immunogenic protein carrier in adjuvant resulted in highest (IgG) antibody levels. The magnitude of enhancement by carrier was greater in rabbits (10- to 100-fold) than in mice (3- to 10-fold). Inbred strains of mice were separable into “high” and “low” responding strains when rI·rC was given either in aqueous solution or in adjuvant. Low responders could be made high responders by complexing rI·rC to a carrier and immunizing in adjuvant. These studies suggest that the immunogenic properties of rI·rC are similar to other materials, and that differences are also apparent.
Macrophage Migration from an Agarose Droplet: Development of a Micromethod for Assay of Delayed Hypersensitivity
Authors: Harrington John T. , Stastny Peter 
Published: December 2022

Abstract
Inhibition of macrophage migration from a glass capillary is the most widely accepted and best characterized in vitro correlate of delayed hypersensitivity. Significant technical limitations of this method have been eliminated by a modified migration inhibitory factor (MIF) method in which macrophages are stabilized in an agarose droplet instead of a capillary tube. This agarose method is technically simple, permitting the rapid assay of large numbers of samples and requiring relatively small volumes of culture supernatant. Experiments comparing the capillary and agarose methods have established the validity and specificity of the agarose method for assay of MIF.
Effect of Chemical and Enzymatic Radioiodination on in Vitro Human Clq Activities
Authors: Heusser Christoph , Boesman Mary , Nordin John H. , Isliker Henri 
Published: December 2022

Abstract
Conditions are described whereby human Clq may be enzymatically radioiodinated with full retention of hemolytic activity. A comparison is made between the chloramine T (CT) and lactoperoxidase (LP) methods of iodination which indicates the following: 1) Clq may be iodinated to a level of 0.2 atoms iodine/molecule by using LP with no detectable loss in hemolytic activity, whereas, at a level of 0.02 atoms incorporated/molecule with CT, Clq is only 50% active. Thus the hemolytic activity of Clq is quite labile to either low levels of iodide incorporation or the oxidizing conditions of the labeling procedure. 2) Its ability to bind immune complexes, conversely, is virtually resistant to the levels and conditions of iodination reported here. 3) With either labeling method, iodide is incorporated exclusively into only the smallest of the three covalently bonded subunits.