bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electron Microscopic Observations on the Nature of Vaccinia Virus Particle Aggregation
Authors: Kim K. S. , Sharp D. G. 
Published: January 2023

Summary
Aggregation among the particles of crude (unpurified) preparations of vaccinia virus is common. Observations with the electron microscope show, in all cases so far examined, that the frequency of groups is greatest for singles and progressively less for each larger size. When the logarithms of group frequency are plotted against the logarithms of group size, the result is a straight line whose slope is a measure of the degree of aggregation. This linear log-log (LLL) distribution is apparent in virus released from cells by freeze-thaw procedure or by ultrasonic waves. It holds for dispersed virus that has been reaggregated by sedimentation into a pellet and resuspended as well as for virus that reaggregates spontaneously. Plaque titrations reveal its influence on the infectivity of aggregated preparations. Its application to interpretation of radiation survival of aggregated virus is discussed.
Ultrasonic waves of 20 kc frequency are shown to produce no damage to fresh individual vaccinia virus particles, in intensities necessary for particle dispersion. Freezing at -60°C, heating at 56°C or ultraviolet irradiation (2537 Å) do not predispose the virus to destruction by 20 kc waves.
Cellular and Humoral Immune Response of Germfree Mice Stimulated with 7S HGG or Salmonella Typhimurium
Authors: Olson George B. , Wostmann Bernard S. 
Published: January 2023

Summary
Germfree mice stimulated with either 7S HGG or Salmonella typhimurium vaccine react in a manner comparable to that of their conv counterparts. In each case the proliferation time of lymphoid cells was reduced from 21 to 22 hr in nonstimulated mice to 17 to 20 hr or 8 to 13 hr in mice stimulated with 7S HGG or S. typhimurium, respectively. Plasmacytopoiesis and hyperplasia was more pronounced in both groups when they were stimulated with the bacterial antigen.
Plasmacytic cells, blast cells and large lymphocytes showed a proportionately greater increase in germfree mice than in conv mice following stimulation with either antigen, suggesting that, even if the germfree animal has fewer competent cells, these cells are less committed due to lack of previous antigenic stimulations.
In vivo antibody production in the germfree-conv model shows a direct relationship to the amount of antibody-producing cells found in these animals, suggesting that this model may be a tool for studies on the kinetics of antibody formation in in vivo nonirradiated conditions.
Inactivation of Poly-DL-Alanyl Bacteriophage T4 with Antisera Specific toward Poly-DL-Dalanine
Authors: Haimovich Joseph , Sela Michael 
Published: January 2023

Summary
Bacteriophage T4B was reacted with N-carbody DL-alanine anhydride, leading to the covalent attachment of alanine residues to the phage, concomitant with extensive loss of viability. The alanylated survivors could be inactivated with anti-phage serum, but were also inactivated specifically with an antiserum possessing antipolyalanine specificity. By using the alanylated phage and the “decision” technique of Jerne and Avegno (14), concentrations of 10-8 to 10-9 g/ml of anti-polyalanine antibody could be detected.
Correlation of Immunologic and Structural Heterogeneity of Bence Jones Proteins
Authors: Nachman Ralph L. , Engle Ralph L. , Copeland Lois 
Published: January 2023

Summary
Immunologic differences among Bence Jones proteins within each major type have been correlated with the peptide maps of individual proteins. The findings suggest that single peptide differences among different proteins of the same immunologic type may determine some of the subtype heterogeneity. The theoretical relationship of this heterogeneity to the mutable amino terminal end of the molecules is discussed.
Virulence and Immunogenicity in Mice of Airborne Encephalomyocarditis Viruses and Their Infectious Nucleic Acids
Authors: Akers T. G. , Bond S. B. , Papke C. , Leif W. R. 
Published: January 2023

Summary
Mice were exposed to aerosols of different strains of the encephalomyocarditis virus group. Responses in mice were different according to strains, virulence being correlated with plaque size. Small plaque-forming strains, ME and Mengo-37A (a heat-resistant mutant of Mengo), were essentially avirulent. The avirulent strains were immunogenic when in sufficient concentration. Aerosol studies with infectious RNA extracted from Mengovirus, ME, and Mengo-37A indicated that the responses in mice were similar to those observed with intact virus. Mengovirus RNA aerosols were lethal for mice, whereas Mengo-37A and ME RNA were avirulent and were not immunogenic in the limited aerosol concentration tested. Mice immunized with intact Mengo-37A virus were refractory to Mengo RNA aerosol challenge.
Loss of Cytotoxicity of Rabbit Anti-Ehrlich Ascites Tumor Cell Antibody Following Pepsin Digestion
Authors: Whitehouse Frank , Kilduff James T. 
Published: January 2023

Summary
Pepsin digestion of cytotoxic 6.6S rabbit Ehrlich ascites tumor cell antibody produces 4.8S antibody which has lost its ability to bind hemolytic guinea pig complement and is not cytotoxic.
Studies on the Transfer of Human Delayed-Type Hypersensitivity
Authors: Baram Peter , Yuan Leo , Mosko M. M. 
Published: January 2023

Summary
Two fractions from tuberculin hypersensitive human white blood cells have been found capable of transferring tuberculin delayed hypersensitivity. One of these (C′-5) is a polynucleotide containing adenine, guanine and cytosine, but no uracil. The second transfer factor is contained in a larger molecular weight (A′) fraction found to have γG-globulin and other globulin and probably α1 lipoprotein as well as ribose indicating RNA.
A fraction containing macroglobulin was unable to transfer delayed hypersensitivity.
A Factor in the Serum of Patients with Persisting Infection That Inhibits the Bactericidal Activity of Normal Serum against the Organism That is Causing the Infection
Authors: Waisbren Burton A. , Brown Imogene 
Published: January 2023

Summary
In some patients with chronic bacterial infections due to gram-negative bacilli the serum is found to contain a factor that inhibits the killing power of normal serum for the particular bacterial strain. The factor is heat stable and strain specific. It has not been found in the absence of chronic infection. It is found commonly, but not regularly, among patients exhibiting chronic pyelonephritis. Whether the factor causes, results from, or only accompanies chronic bacterial infections remains unknown.
Further Studies on the Anti-Globulin Factors in Human Serum to the Pepsin Digested Fragment of the RI Anti-RH Antibody
Authors: Waller M. , Blaylock K. 
Published: January 2023

Summary
Serum reactivity to erythrocytes sensitized with pepsin digested anti-Rh antibody Ripley was found to be almost universal in 795 undiluted sera. The donor Ripley himself showed a titer of 1:40 with sensitized cells. Pepsin digested globulins of negatively reacting sera showed the same degree of inhibition as pepsin digested globulins of positively reacting sera. Specific immunizations with Brucella and Vi antigens had no influence on the titer of this anti-globulin factor. Only a minimal degree of digestion of the globulin molecule is necessary to reveal the hidden determinant.
Density Separable Fractions during Growth of Measles Virus
Authors: Numazaki Yoshio , Karzon David T. 
Published: January 2023

Summary
The appearance of viral activities during the growth of measles virus in AV3 cells was analyzed employing density-gradient centrifugation in cesium chloride. Two density forms of infectious virus were demonstrated, with densities of 1.23 to 1.24 g/ml (M form) and 1.20 to 1.21 g/ml (L form). Sonication shifted the L form to a lower density, 1.16 g/ml (Ls form) with an increase in titer. The L form appeared early in the growth cycle, disappeared and was replaced by the M form which appeared later in the cycle. The M form was released and appeared to be the complete mature virion. The L form was poorly released and may represent either an aberrant end product or a precursor to the M form.
Hemagglutinin, complement-fixing and hemolytic activities accompanied the infectious peaks. Hemolytic activity corresponded closely to the infectivity peaks, but hemagglutinin and complement-fixing activity demonstrated a broad heterodensity. A high density (1.30 g/ml) noninfectious complement-fixing peak was shown.
Soluble Antigen of Measles Virus
Authors: Numazaki Yoshio , Karzon David T. 
Published: January 2023

Summary
Three complement-fixing (CF) antigens of measles virus, separated on the basis of buoyant density, were further analyzed with respect to sedimentation characteristics and antibody response. The heavy (H) noninfectious CF fraction (density 1.30 g/ml) could be distinguished from the less dense infectious CF antigens (M peak to meniscus, 1.24 to Ü1.18 g/ml). The H-CF fraction was shown to remain in the supernatant fluid after centrifugation at 20,000 to 30,000 rpm. This fraction is therefore of small particle size and has a density compatible with the nucleoprotein internal component. Antibody response to H-CF fraction occurred following measles viral replication and not after immunization with inactivated vaccine. The H-CF fraction has characteristics resembling those of the soluble antigens of other myxoviruses.
Inactivation and Density Studies with Para-Adenovirus 7 (SV40-Adenovirus “Hybrid” Population)
Authors: Butel Janet S. , Rapp Fred 
Published: January 2023

Summary
Inactivation and density studies were performed with PARA-adenovirus 7, a “hybrid” population of defective SV40 and adenovirus. The ability of PARA and of “pure” SV40 to induce SV40 tumor antigen in simian cells were inactivated at similar slow rates upon exposure to ultraviolet light, while the infectivities of SV40 and PARA were rapidly destroyed. The infectivity of PARA was found to be more susceptible to inactivation by ultraviolet light than was the infectivity of either adenovirus 7 or SV40. The average 37% dose was 12 sec for PARA, 22 sec for adenovirus 7, and 28 sec for complete SV40. Both PARA and adenovirus 7 in the “hybrid” population were equally sensitive to photodynamic inactivation after incorporation of either neutral red or proflavine. Neither component was affected by treatment with ribonuclease or deoxyribonuclease. Both members showed similar rates of heat inactivation at 50°C. The PARA and adenovirus 7 in the “hybrid” stock both banded at a buoyant density of 1.34 in cesium chloride. Except for sensitivity to inactivation by ultraviolet light, PARA could not be differentiated from adenovirus.
Immunocompetence of Transferred Thymus-Marrow Cell Combinations
Authors: Claman Henry N. , Chaperon Edward A. , Triplett R. Faser 
Published: January 2023

Summary
Suspensions containing adult marrow and thymus cells were far more active in producing anti-sheep red cell hemolysins when transferred to irradiated syngeneic recipient mice than can be accounted for by summating the activities of each cell population alone. Such synergistic activity was not present in 1-day-old thymus cells, but was present in 6-day-old thymus cells. Spleen cells 6 days old, however, were inactive. Adult thymus, but not adult marrow, acted in synergism with a small number of adult spleen cells. The efficacy of adult thymus cells was abolished by 500 r (in air) given to donors. Subcutaneous thymus grafts were not active. The order of injection of thymus or marrow cells was not critical.
The data confirm the hypothesis of interaction between thymus and marrow cells, although the nature of this interaction is obscure.
Effects of Mild Periodate Oxidation on Antibodies
Authors: Andersen Burton R. , Abele Donald C. , Vannier Wilton E. 
Published: January 2023

Summary
The effect of mild periodate oxidation of rabbit antibody to BSA and HGG and human skin sensitizing antibodies to ragweed were studied. Oxidation of carbohydrate was demonstrated by the marked reduction in fucose and neuraminic acid and moderate reduction in the hexose and hexosamine of the rabbit antibody. Amino acid analysis and optic rotation studies indicated that there was little if any protein oxidation.
The marked decrease in direct PCA activity and the slight decrease in reverse PCA and precipitating antibody levels suggest that the antibody combining site was largely unaltered by oxidation and that the major effect was probably on the site responsible for tissue fixation or a structure necessary for the mediation of hypersensitivity reactions. Skin sensitizing antibodies were also inactivated by mild periodate oxidation but the site affected has not been determined.
Other effects of oxidation on rabbit antibody included an increase in electrophoretic mobility and a tendency to form aggregates. No change in the antigenic determinants of periodate oxidized RGG was detected.
The Sedimentation and Antigenic Properties of Proteins in Nasal and Other External Secretions
Authors: Rossen Roger D. , Butler William T. , Vannier Wilton E. , Douglas R. Gordon , Steinberg Arthur G. 
Published: January 2023

Summary
The antigenic characteristics of γA-globulin, γG-globulin, albumin and siderophilin from nasal secretions and sera have been compared and their sedimentation behavior studied by sucrose density gradient ultracentrifugation followed by specific quantitative assay of the concentration of these proteins in the gradient fractions.
γG-globulin in whole nasal secretions had a mean sedimentation coefficient of 6.5 S ± 0.7 S (1 S.D.), closely similar to the sedimentation behavior of γG-globulin isolated from whole serum by DEAE-cellulose chromatography or by starch block electrophoresis. In contrast, γG-globulin in samples of whole serum showed a mean sedimentation coefficient of 7.3 S ± 0.6 S (1 S.D.). The population of γG-globulins present in nasal washings included the γGa (γ2a), γGb (γ2b) and γGc (γ2c) subclasses but was antigenically deficient with respect to γGd (γ2d) or possibly unidentified subclasses of γG-globulin present in serum.
γA-globulin in both nasal secretion and serum showed considerable size heterogeneity. The major part of the nasal secretion γA-globulins sedimented between 9–14 S, while most of the serum γA-globulin was found in the 7–9 S region. γA-globulin, isolated by DEAE-cellulose chromatography from nasal washings, exhibited sedimentation behavior closely similar to that of the γA-globulin in whole nasal secretion. Nasal secretion γA-globulin, heavier than 9 S, possessed antigenic determinants not found in γA-globulin from serum, while 5–7 S γA-globulin from nasal secretion and γA-globulin from serum were antigenically similar. Samples of isolated nasal secretion γA-globulin from four out of five volunteers, however, lacked Inv allotypes, although all samples possessed antigens associated with both K and λ type light chains.
Albumin and siderophilin in nasal secretions and serum had similar sedimentation properties, and the albumin in nasal secretions was antigenically identical with its serum counterpart.
Comparison of the properties of tears and parotid saliva to nasal secretions from the same individuals revealed that γA-globulin in the three secretions had the same sedimentation behavior and antigenic characteristics.
Some Observations on the Abo Antigen Sites of the Erythrocyte Membranes of Adults and Newborn Infants
Authors: Haberman Sol , Blanton Pat , Martin James 
Published: January 2023

Summary
Horse spleen ferritin may be conjugated to human immune anti-A globulins to give a reagent that is useful in locating the sites of A antigens on the human erythrocyte.
Ferritin-tagged antibodies were found to coat the outer cell wall only of adult red cells. However, in the case of erythrocytes obtained from umbilical cord blood some ferritin was seen coating the cell wall, but many of the cells showed vacuoles that were filled with these ferritin granules.
Pinocytosis was seen more frequently in the antibody-treated infant cells, and accumulations of ferritin-tagged antibodies were observed within the forming vesicles. This phenomenon was not seen when ferritin was added to the cell suspensions in the absence of antibody.
Some possible implications of these findings as related to ABO hemolytic disease of newborns and to the direct antiglobulin test on blood samples obtained from these cases are discussed.
The Morphologic Characteristics of 19S Antibody
Authors: Almeida June D. , Brown F. , Waterson A. P. 
Published: January 2023

Summary
Using foot-and-mouth-disease virus as an antigen, the negative staining technique has been employed to study the morphologic differences between 7S and 19S antibody. 7S antibody was purified by the use of diethylaminoethyl cellulose chromatography and 19S antibody by means of sucrose gradient centrifugation. Complexes were made with the virus and each of the two antibody species and examined in the electron microscope. 7S antibody appeared as a filament measuring roughly 27 × 250 Å. 19S antibody also appeared as a filament but had dimensions approximately 50 × 370 Å.
Attachment to the virus particle seemed to be mainly by sites at either end of the 19S molecule but other binding sites may be present. Looping was found to be a frequent occurrence in preparations of virus and 19S antibody.
Demonstration of Tissue-Specific Soluble Antigens in Human Skin by Immunodiffusion
Authors: Aoki Toshiyuki , Fujinami Tokuji 
Published: January 2023

Summary
Antisera to soluble preparation of human skin were prepared in rabbits and used to determine antigenic components of human skin and to compare these with antigens of other human organs and tissues by immunodiffusion and immunoelectrophoresis. There were several antigens which were common to the skin, liver, kidney, lung, gastric mucosa, spleen, heart, brain, cornea, lens and uvea which were different from serum antigens.
After absorption of the antisera with human serum and several organ antigens, three precipitation lines were recognized which were specific to skin and which were not observed in tests with skin preparations of dog, cat, rabbit, guinea pig, rat and mouse. The major human skin-specific antigen was stable to heat of 70°C for 3 min and to dialysis to 0.01 M phosphate buffer solution. These skin-specific antigens are considered to be present in the epidermis.
The Pathogenesis of Theiler's GD VII Encephalomyelitis Virus Infection in Mice as Studied by Immunofluorescent Technique and Infectivity Titrations
Authors: Liu Chien , Collins Julius , Sharp Eleanor 
Published: January 2023

Summary
By means of infectivity titrations and immunofluorescent staining, the pathogenesis of Theiler's GD VII virus infection in mice was studied. After intracerebral inoculation of virus, infection appeared to start at the site of inoculation and then spread along the ventral part of the brain and the hippocampus. Following intranasal inoculation, virus gained entrance to the central nervous system (CNS) through the olfactory bulbs and olfactory tracts to initiate infection in the brain. By feeding mice with GD VII virus, small amounts of the virus could be demonstrated in visceral organs by infectivity titrations while much larger amounts of virus were found in the CNS when encephalitis became apparent. Use of the immunofluorescence technique did not enable us to localize the primary sites of viral multiplication prior to invasion of the central nervous system in mice infected by gavage.
Studies on the Specificity of the Cellular Infiltrate of Delayed Hypersensitivity Reactions
Authors: Cohen Stanley , McCluskey Robert T. , Benacerraf Baruj 
Published: January 2023

Summary
An autoradiographic study has been performed in an attempt to demonstrate specifically sensitized cells in delayed hypersensitivity reactions in guinea pigs. In one experiment, guinea pigs were given H3-thymidine at various times after immunization with a single antigen and all were skin tested 22 days after immunization. It was found that there was a continuous increase in the percentage of labeled mononuclear cells in skin reactions as a function of time of administration of H3-thymidine. In another experiment, guinea pigs were immunized with two unrelated antigens and given H3-thymidine in such a manner as to label cells proliferating in response to the first, but not the second antigen. No difference was detected in the percentage of labeled infiltrating mononuclear cells at skin reactions elicited simultaneously with each antigen at separate sites. These observations demonstrate that the specifically sensitized cells which are believed to initiate the inflammation of delayed hypersensitivity reactions are too few to be detected by the methods available.
Application of the Paired Label Radioantibody Technique to Tissue Sections and Cell Smears
Authors: Tanigaki Nobuyuki , Yagi Yasuo , Pressman David 
Published: January 2023

Summary
A micro-scale modification of the paired label radioantibody technique has been developed to determine the reactivity of antiserum globulin with tissue sections or cell smears. A mixture of 125I-labeled IgG from antiserum and 131I-labeled IgG from normal serum is applied on test specimens fixed on microscope coverslips. After incubation for 60 min at room temperature, the specimens are washed and assayed for the radioactivity due to 125I and 131I. The degree of the reactivity of antiserum IgG was expressed by the uptake quotient, the quotient of the specific uptake over the nonspecific uptake.
The method is sensitive and reproducible under the conditions given. It is suitable for comparing a large number of specimens and particularly useful where the test materials, tissues or cells, are available only in limited quantities.
Various factors involved in the reaction—reaction time, concentration of antibody globulin, area and thickness of sections, antigen content and absorption with tissue sediments—were evaluated in detail.
Thermostable Brain-Specific Autoantigen
Authors: Milgrom Felix , Tuggac Z. Maide , Campbell Walter , Witebsky Ernest 
Published: January 2023

Summary
Evidence was presented for autoantibody formation against a thermostable ethanol-insoluble antigen (BE antigen) characteristic for brain. Rabbit antisera to brain BE of human and porcine origin combined with rabbit brain BE. Antisera of rabbits immunized with rabbit brain BE and of pigs immunized with porcine brain BE contained brain-specific antibodies acting upon brain BE originating from the antibody-forming animal. In addition to these antibodies, some anti-brain BE sera contained autoantibodies that combined with a non-organ-specific antigen.
The Alteration of Endotoxin by Postheparin Plasma and its Purified Fractions
Authors: Schultz Duane R. , Becker Elmer L. 
Published: January 2023

Summary
Fractionation of the delipidized euglobulin from guinea pig postheparin plasma on DEAE-cellulose resulted in one protein peak in the effluent and two to three protein peaks following an NaCl-gradient. Both endotoxin detoxifying action and lipoprotein lipase activity were found in the fractions prior to the application of the NaCl-gradient, if the fractions were collected in heparin. Without added heparin, neither of the two activities was obtained. Associated with both detoxifying and lipase activities was the release of unesterified fatty acids and the endotoxin-clearing reaction.
Heating the postheparin plasma euglobulin fraction either had no effect or partially inactivated the endotoxin-detoxifying factor, but destroyed lipoprotein lipase activity. Both unesterified fatty acid release from the endotoxinalbumin-euglobulin mixtures and the endotoxin-clearing reaction were destroyed by heat.