bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of HL-A Antigens in Synchronized Cultures of Human Lymphocytes
Authors: Pellegrino M. A. , Ferrone S. , Natali P. G. , Pellegrino A. , Reisfeld R. A. 
Published: December 2022

Abstract
Human histocompatibility loci control the expression of antigenic factors which elicit an immune response resulting in the destruction of allografts. These HL-A alloantigens located on the surface of all nucleated cells thus play an important role in the graft rejection phenomenon. Recently there have also been reports linking the occurrence of certain HL-A determinants with the susceptibility to several diseases (1). In order to investigate these phenomena at the molecular level, there have been several efforts to isolate HL-A antigens in soluble form to facilitate their thorough biologic and chemical characterization. Since it is practically impossible to isolate sufficient amounts of antigens for this purpose from genetically uniform tissue sources, there has been an increased utilization of cultured human lymphocytes (2).
To gain an understanding of the expression of HL-A antigenic determinants on the surface of both synchronized and non-synchronized cultured cells during the cell cycle, we applied a quantitative microabsorption technique and an indirect immunofluorescence test.
Suppressor T Cells
Authors: Gershon Richard K. , Cohen Philip , Hencin Ronald , Liebhaber Stephen A. 
Published: December 2022

Abstract
The antigen-induced DNA synthetic response of a number of different thymocyte populations was studied in the spleens of lethally irradiated recipients by incorporation of 125I 5-iodo-2-deoxyuridine. The response of certain cell combinations was not only less than the sum of the two responding alone but less than one of the individual cell populations in the combination. The following combinations had this effect: 1) “Educated” and normal thymocytes &lt; “educated” alone in the response to sheep red cells (SRBC); 2) parental and F1 thymocytes &lt; parental alone in F1 hosts; 3) cortisone resistant (in a low dose) and normal thymocytes &lt; normal alone in the response to SRBC. Thus, thymocytes are capable of suppressing the antigen-induced response of other thymocytes without the mediation of B cells or their product (i.e., antibody).
Friend Leukemia Virus Infection in Germfree Mice Following Antigen Stimulation
Authors: Kouttab N. M. , Jutila J. W. 
Published: December 2022

Abstract
The course of leukemia produced by Friend leukemia virus (FLV) in male and female BALB/c mice was compared in conventionally-reared (CR) and germfree (GF) mice. Hematologic and pathologic studies showed that whereas the disease process in CR mice was severe and resulted in death of the mice within a period of 2 to 3 months, few or mild symptoms appeared in GF mice. However, when GF mice were stimulated with sheep erythrocytes (SRBC), mortality from FLV challenge was markedly increased but without typical symptoms of a leukemic process. Immunologic assays showed that FLV completely inhibited the spleen plaque-forming cell response to SRBC in CR mice. This indicates that GF mice may not possess the “target cell” for FLV, and that this “target cell” is probably a precursor to antibody-producing cells.
The Requirement for Serum Complement in the Detoxification of Bacterial Endotoxin
Authors: Johnson Kent J. , Ward Peter A. 
Published: December 2022

Abstract
The in vitro detoxification of bacterial endotoxin requires both the fifth (C5) and and sixth (C6) components of complement and proceeds in the presence of 0.01 M EDTA. Addition of purified C5 or C6 to the genetically deficient serum corrects the defect in detoxification of endotoxin. Mice lacking C5 show a greatly increased susceptibility to the lethal effects of endotoxin and C6 deficient rabbits, in contrast to normal rabbits, fail to develop an increased detoxifying capacity in serum as a result of recent exposure to endotoxin. While human plasma is more effective than serum in detoxifying endotoxin, this cannot be completely ascribed to the reduction in levels of cations. The mechanism by which the complement system participates in the detoxification of endotoxin is peculiarly different from the usual sequential pathways of the complement system. In broad biologic terms, these findings suggest a previously unrecognized, protective function of the complement system.
Sensitization and Neutralization of Adenovirus by Specific Sera Against Capsid Subunits
Authors: Wadell Göran 
Published: December 2022

Abstract
The relative importance of the two different type-specific determinants (one on the hexons, the other on the distal part of the vertex projections) on the adenovirus capsid for the induction of antibodies capable of neutralizing virus infectivity in vitro was studied. Rabbit antisera against fibers or pentons displayed no demonstrable or low neutralizing activity when assayed by end point titration in tubes. Antisera against hexons of members of subgroup I and II and of serotype 4 consistently displayed high ratios of neutralizing capacity over type-specific complement fixation (CF) activity. However, sera against hexons of adenovirus types belonging to subgroup III showed a lower neutralizing capacity relative to type-specific CF activity. Two different populations of hexons of serotype 2 (subgroup III) could be separated by anion exchange chromatography and iso-electric focusing. Sera against certain preparations of hexons obtained by these techniques displayed very low neutralizing activity in spite of the presence of large amounts of type-specific CF antibodies.
Neutralization by sera against hexons of members of subgroup III (except type 4) was enhanced after addition of sheep anti-rabbit sera, whereas the high titers of the corresponding sera of the remaining serotypes remained unaffected. By employing the same technique, dramatic enhancement of the neutralizing capacity of sera against fibers or pentons of members of all subgroups was demonstrated. Fab and F(ab′)2 fragments of hexon or fiber specific antibodies were totally devoid of virus-neutralizing activity but retained the capacity to interact with antigenic determinants on fibers and hexons as demonstrated by hemagglutination enhancement, hemagglutination inhibition and an antibody blocking test based on CF. Combined with sheep anti-rabbit antibodies, these virus-specific antibody fragments were capable of neutralizing adenovirus infectivity indicating that Fc fragments of virus-specific antibodies were not required.
The Purification of Adenovirus Neutralizing Antibody: Adenovirus Type 5 Hexon Immunoadsorbent
Authors: Haase A. T. , Pereira H. G. 
Published: December 2022

Abstract
Preparation of an immunoadsorbent of crystalline hexon of adenovirus type 5 bound to Sepharose is described. The immunoadsorbent was employed to purify antibody to adenovirus type 5 hexon from antiserum prepared against a mixture of the three capsid antigens. In addition, separation of antibody with type-specific neutralizing activity from group-specific non-neutralizing hexon antibody has been achieved.
Age Dependent Resistance to Polyoma and Murine Sarcoma Viruses in Mice
Authors: Hirsch Martin S. , Proffitt Max R. , Tracy Gay S. , Black Paul H. 
Published: December 2022

Abstract
The mechanisms of age-dependent resistance to polyoma virus and murine sarcoma virus-Harvey (MSV-H) were evaluated in inbred mice. Transfer of unsensitized, adult CBA lymphocytes to syngeneic neonatal mice protected them against tumor development following subsequent inoculation of polyoma virus. The protective effect was proportional to the number of lymphocytes transferred, and was related both to enhanced rejection of polyoma virus transformed cells, and to more effective elimination of virus. Equal numbers of adult macrophages or mixtures of lymphocytes and macrophages were less effective in transferring protection against polyoma-oncogenesis. In contrast to the effects of cell transfer on polyoma virus infection, transfer of unsensitized adult C3H lymphocytes or macrophages to syngeneic neonatal mice had no effect on subsequent infection with MSV-H.
Activation of the First Component of Complement
Authors: Loos M. , Borsos T. , Rapp H. J. 
Published: December 2022

Abstract
We present evidence for an activation step in the C1 molecule that occurs after the binding of C1 and before the appearance of C1̄ activity. Evidence for this internal activation step was obtained by the use of two different inhibitors of C1̄: C1̄-inactivator (I1) and a pentosan-poly-sulfo-ester (Sp54). Sp54 and I1 do not inhibit the uptake of C1. Sp54 inhibits a population of bound C1 not inhibitable by I1. C1 taken up in the presence of Sp54 are not inhibitable either by I1 or by Sp54. C1 taken up in the presence of I1 are inhibitable by Sp54 but not by I1. Sp54 is capable of inhibiting the hemolytic action of EAC1q4 while I1 is not.
The data suggests that the internal activation step involves the subcomponent C1q.
Pharmacologic Control of Allergic Histamine Release in Vitro: Evidence for an Inhibitory Role of 3′,5′-Adenosine Monophosphate in Human Leukocytes
Authors: Bourne Henry R. , Lichtenstein Lawrence M. , Melmon Kenneth L. 
Published: December 2022

Abstract
The ability of catecholamines, prostaglandins and histamine to stimulate accumulation of 3′,5′-adenosine monophosphate (cyclic AMP) in human leukocytes correlated well with their ability to inhibit antigen-induced release of histamine from cells of allergic donors in vitro. In both systems the order of potency of adrenergic agents was characteristic of the beta-receptor (isoproterenol τ epinephrine τ norepinephrine τ phenylephrine), and prostaglandins E1 and E2 were equally active, while PGF1α produced no effect. A beta-adrenergic blocking agent, propranolol, specifically antagonized the effect of catecholamines on both cyclic AMP and histamine release, but had no effect against either the prostaglandins or histamine.
These results strongly support the hypothesis that cyclic AMP acts as a “second messenger” in leukocytes to inhibit allergic release of histamine. Like dibutyryl cyclic AMP and the methylxanthines, all agents which increase synthesis of leukocyte cyclic AMP act to block antigenic histamine release at an early stage of the release process, although the precise mechanism has not yet been defined.
Immunologic Alterations in Bovine Serum Albumin Resulting from Partial or Complete Reduction and Alkylation
Authors: Goetzl Edward J. , Peters John H. 
Published: December 2022

Abstract
Purified monomer (4S) and dimer (7S) bovine serum albumin (BSA) were isolated from solutions of crystalline BSA by gel filtration. Mercaptoethanol reduction of BSA in buffered saline resulted in the appearance of only three sulfhydryl groups per molecule (3-SH BSA). Complete reduction in 8 M urea produced 34 free sulfhydryl groups per molecule (34-SH BSA). These BSA preparations were studied by optical rotatory dispersion, ultracentrifugation, quantitative precipitation and hemagglutination with homologous and heterologous antisera, and immunologic cutaneous reactions.
Significant distortion of the native BSA conformation by complete reduction and carboxymethylation (34-SH BSA) resulted in loss of precipitation with anti-native BSA. Partial unfolding of the native conformation of BSA resulted in greater precipitation with anti-native BSA and greater reactivity with anti-3-SH BSA hemagglutinins. This increase in antigenic reactivity was directly proportional to the loss of native α-helix content and accordingly was greater for 3-SH BSA than dimer native BSA. The augmented antigenic binding is felt to be due to an exposure of hidden antigenic determinants or the creation of new determinants associated with these conformational alterations.
Completely reduced carboxymethylated 34-SH BSA is a potent immunogen inducing high titers of non-IgG antibodies with passive hemagglutination and cutaneous anaphylactic activities, but no precipitating ability. Monomer 34-SH BSA does not precipitate or fix complement with any anti-BSA antisera, and therefore may be a univalent antigen. The strong Arthus reaction produced by the 34-SH BSA immunologic system despite a lack of precipitation and complement fixation in vitro suggests the possibility of antigenic aggregation in vivo.
Synergism Between Peyer's Patch Cells and Spleen Cells in Humora Antibody Production
Authors: Coppola Edward D. , Aboul-Enein Adel , Kopycinski Clark F. , DeLuca Frank 
Published: December 2022

Abstract
Good and his colleagues have suggested that vertebrate immunity may have evolved into a two-component system: a thymus-dependent component primarily regulating cellular immunity, and a bursal-dependent system primarily regulating humoral immunity. These workers proposed that such structures as the tonsils, appendix and Peyer's patches may be the primary or central mammalian analogue of the avian bursa of Fabricius, whose removal causes ablation of humoral antibody responses in birds. They found that extirpation of gut-associated lymphoepithelial tissue in rabbits, followed by irradiation, produced deficiencies of specific antibody and immunoglobulin formation (1–3).
We have been interested in defining a possible role for Peyer's patches in humoral immunity. We studied first the immune response of spleen and Peyer's patch cells in 1-month-old C57BL/6 mice stimulated with intraperitoneal (i.p.) injections of 2.5 × 108 sheep red blood cells (SRBC).
Synthesis of Rat IgE by Aerosol Immunization
Authors: Van Hout Christine A. , Johnson Herbert G. 
Published: December 2022

Summary
After a single 5-min exposure to an aerosol containing ovalbumin, rats produced a heat labile, skin sensitizing antibody by 14 days. By radioiodination of the protein the amount of antigen deposited in the respiratory tract during this immunization was calculated to be 12.8 µg. The amount of protein swallowed by the animals (80 µg) was incapable of elaborating an IgE response. The synthesis of IgE under these conditions was absolutely dependent on heat-killed Bordetella pertussis vaccine given i.p. before exposure. Second exposures to antigen resulted in renewed and accelerated IgE production. Repeated aerosolization with a low dose of antigen (0.1%) caused no detectable antibody synthesis.
Human Mononuclear Leukocyte Chemotaxis: A Quantitative Assay for Humoral and Cellular Chemotactic Factors
Authors: Snyderman Ralph , Altman Leonard C. , Hausman Marvin S. , Mergenhagen Stephan E. 
Published: December 2022

Abstract
The participation of the mononuclear leukocyte (MNL) in wound healing and in host immunity is well documented (1, 2). Despite this, the mechanism by which these cells accumulate in local tissue sites is poorly defined. Recent studies have shown that MNLs derived from rabbit or guinea pig inflammatory exudates can respond chemotactically to various stimuli in vitro (3–6; M. S. Hausman, R. Snyderman and S. E. Mergenhagen, submitted for publication). However, quantitative methods for the study of human MNL chemotactic activity have not been previously reported. An assay of human MNL chemotaxis would allow a clearer definition of human MNL chemotactic factors and also the assessment of MNL function in various human disease states. The present report describes a reproducible, quantitative assay for humoral and cellular factors of human origin which are chemotactic for human MNLs.
Materials and Methods. Source of MNLs.
A New Serum Factor in Normal Rabbits
Authors: Woolsey M. E. , Mandy W. J. 
Published: December 2022

Abstract
Newborn rabbits were given various doses of immunosuppressive drugs (6-mercaptopurine, cortisone or cytosine arabinoside) shortly after birth and at various intervals thereafter. The effect of these drugs on the production of homoreactant (HR) was demonstrated by a decrease in the levels of HR significantly below the levels found in control rabbits of the same litter at the same age. The reduction in HR activity was not attributed to an overall decrease in the immunoglobulin synthesis.
Since immunosuppressive drugs presumably alter the immune response at the level of antigen recognition, these findings provide indirect but supportive evidence that HR production is mediated by antigenic stimulation.
Differentiation of Binding from Complete Activation by Use of Heterologous Components of Complement
Authors: Koethe Susan M. , Austen K. Frank , Gigli Irma 
Published: December 2022

Abstract
C2hu can bind to cellular intermediates of the complement system in three forms. Native C2 fixes to the EAC4̄ intermediates presumably without alteration such that it can transfer quantitatively to a compatible EAC1̄hu4̄hu recipient cell, or can be activated on the cell by the introduction of C1̄. C2hu interaction with a homologous EAC cell forms a convertase capable of continuing the hemolytic sequence upon the addition of the terminal components. Finally C2hu can be bound by EAC1̄gp4̄gp to achieve an intermediate designated EAC1̄gp4̄gp2hhu; C2hhu differs from native C2hu by its failure to transfer and from fully activated C2hu by its failure to decay or efficiently mediate the hemolytic sequence. An EAC1̄gp4̄gp2hhu intermediate will, however, bind C3hu in a hemolytically inactive state designated C3hhu. C3hhu differs from native C3hu in that it is inactivated by the C3b inactivator and from C3b in that it fails to participate in immune adherence. Addition of C2gp to EAC1̄gp4̄gp2hhu3hhu intermediate imparts hemolytic activity and the ability to react in immune adherence. The C2gp presumably forms a homologous convertase on vacant SAC1̄gp4̄gp and in this way activates a neighboring C3hhu. C2hhu will fulfill the C2 requirements for C5 activation in the presence of C3b even though C2hhu does not fully activate C3hu and cells containing both C2hhu and C3hhu apparently do not activate C5.
Recombination of Genes Coding for Constant and Variable Regions of Immunoglobulin Heavy Chains
Authors: Kindt T. J. , Mandy W. J. 
Published: December 2022

Summary
In one member of a rabbit family evidence has been obtained for a cross-over for genes coding from group a and group d rabbit heavy chain allotypic markers. Subsequent breeding of the animal in which the recombination occurred showed persistence of this new linkage. This observation is most readily interpreted in terms of a multi-gene system coding for the immunoglobulin heavy chain.
In Vitro Responses of Peripheral Blood Lymphocytes in Experimental Allergic Encephalomyelitis
Authors: Fowler Ira 
Published: December 2022

Abstract
Tritiated thymidine incorporation was determined in cultures of peripheral leucocytes taken from rabbits in which experimental allergic encephalomyelitis (EAE) was produced by immunization against either whole brain (WB) or myelin basic protein (BP). There was a significant increase in 3H-thymidine uptake in cultures of lymphocytes of animals with EAE induced with WB when stimulated with WB, but there was no increase with BP added to these cultures. When the lymphocyte donors were rabbits in which EAE was produced by BP, 3H-thymidine incorporation was increased significantly by the addition of either WB or BP to the cultures. Lymphocytes of all donors responded to stimulation in vitro before the onset of symptoms of EAE and failed to respond after the disease progressed. Lymphocytes taken from animals given protective injections of either WB or BP failed to respond to stimulation by these antigens.
The Early Immune Response and Immunoglobulins of Opossum Embryos
Authors: Rowlands David T. , Blakeslee Dennis , Lin Hshu-Hshing 
Published: December 2022

Abstract
The immune responses of developing opossoms were studied after one or two injections of bacteriophage f2. Antibodies could be detected in serum of developing opossums as early as 7 days after immunization and peak antibody responses were reached 14 or more days after immunization. A second injection of antigen usually increased the level of serum antibodies only slightly. The antibodies of these embryos were further studied by sucrose density gradient centrifugation. The earliest antibodies appeared as 13S “embryonic” antibodies localized between 19 and 7S positions in the sucrose density gradients. IgM antibodies appeared later as the embryonic antibodies decreased. IgG antibodies were never prominent and were the last to appear in measurable amounts during development.
The Influence of Calcium, Magnesium and Cyclic Adenosine 3′,5′-Monophosphate on the Mixed Lymphocyte Reaction
Authors: Whitney Richard B. , Sutherland Robert M. 
Published: December 2022

Abstract
EDTA inhibits lymphocyte transformation in the mixed lymphocyte culture reaction as it does in PHA containing cultures. The effect is most likely due to binding of Ca++ and Mg++ required for the initiation and completion of the response since transformation does not occur in cultures deficient in these ions. Exogenous cyclic adenosine 3′,5′-monophosphate (cAMP) can potentiate or inhibit the mixed lymphocyte reaction depending on concentration and duration of exposure. The possible interaction of divalent cations and cAMP in lymphocyte transformation is discussed.
γM Alloantibody Elicited by First-Set Renal Allografts: in Vivo and in Vitro Studies
Authors: van Breda Vriesman Peter J. C. , Feldman Joseph D. 
Published: December 2022

Abstract
γM alloantibody (allo γM) was produced in Lewis (Le) rats after a 5- to 7-day residence of Brown Norway (BN) renal grafts. The isolated, purified and isotopically labeled allo γM fixed to spleen, lung, liver and erythrocytes after intravenous injection into BN target rats, but did not fix to kidney unless the renal vein was clamped for 3 min. Allo γM fixed promptly in BN kidneys grafted into Le recipients. In such kidneys allo γM specifically bound to endothelia of glomerular and intertubular capillaries and of medium-sized arteries. It did not bind in vivo to renal tubular cells but did so in vitro. At least two γM antibodies were detected. One reacted with kidney, spleen cells and erythrocytes, the second only with spleen cells. Intravenous infusion of allo γM into target BN rats produced extensive pulmonary hemorrhages but the production of these lesions lacked specificity. Allo γM elicited by renal graft was strain but not organ specific, i.e., it reacted with transplantation antigens shared by kidney and by other organs and tissues of the immunizing strain. Its role in the rejection process could not be established.
Induction of Antiidiotypic Antibodies Directed to Antibenzoate Antibody in Rabbits Actively Synthesizing High Titers of Antibenzoate Antibody
Authors: Spring-Stewart Susan , Brient Bruce W. , Nisonoff Alfred 
Published: December 2022

Abstract
In efforts to elicit antiidiotypic antibodies, each of 16 rabbits was immunized with purified antibenzoate antibodies prepared in an individual donor rabbit of allotype matched to the recipient. Two types of recipients were used: 1) rabbits hyperimmune to the benzoate hapten; 2) rabbits hyperimmune to the noncross-reacting hapten, DNP. Nearly all recipient rabbits responded by producing anti-idiotypic antibodies, and no significant quantitative differences were detected in the two groups. This result implies that the rabbits producing antibenzoate antibodies at the time of immunization were not tolerant to the antibenzoate antibodies injected.
Efforts were also made to elicit antiidiotypic antibodies by self-immunization of donor rabbits with their own antibenzoate antibodies after rest periods totaling 23 to 36 weeks. Such experiments were unsuccessful, indicating that a state of tolerance to the rabbit's own antibodies had persisted.
Thus rabbits remained tolerant to their own idiotypic determinants, whereas the capacity to respond of other rabbits, actively synthesizing high titers of antibenzoate antibody, was not impaired. The results emphasize the broad spectrum of idiotypic specificities in different rabbits on molecules specific for a single hapten group.