bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction of Protein Antigens and Antibodies
Authors: Kleinschmidt W. J. , Boyer P. D. 
Published: January 2023

Summary
Experiments on the solubilization and dissociation of egg albumin-anti-egg albumin precipitates have been conducted with acid, alkali, salts, dodecyl sulfate, and urea and with combinations of these substances.
Alkaline buffers of pH 11.0 and higher at 2 C dissolved the egg albumin-anti-egg albumin precipitate. Electrophoretic examination of dissolved precipitates showed no dissociation of the precipitate at pH 11.15, approximately 17% dissociation at pH 11.7, and 100% dissociation at pH 12.3. Tests with egg albumin and isolated rabbit immune γ-globulin revealed that the immune γ-globulin was altered only slightly at pH 11.7 but that marked changes occurred at pH 12.3.
A mixture of 0.3 M KCNS and 2 M urea at pH 10.75 produced complete dissolution of egg albumin-anti-egg albumin precipitates: however, electrophoretic analysis revealed only approximately 5% dissociation under these conditions. Increase in the pH of the mixture resulted in changes in the egg albumin and immune γ-globulin as measured by survival tests.
Egg albumin-anti-egg albumin precipitates dissolved completely in acid buffers at pH 3.4 or lower. Electrophoretic evaluation of possible dissociation at pH 2.8–3.2 was not feasible because of the similar mobilities of the components in this pH range. Exposure of immune γ-globulin at pH 3.4 or less produced changes as evidenced by complex formation leading to increased precipitate formation following egg albumin addition.
The dependence of dissociation of egg albumin-anti-egg albumin precipitates upon conditions sufficiently drastic to cause changes in the antibody component of the precipitates when tested separately suggest that the forces responsible for the primary interaction of egg albumin and anti-egg albumin are of the same nature and magnitude as those responsible for maintaining the native configuration of the γ-globulin.
Effect of Multiple Injections of Antigen upon the Specificity of Antisera
Authors: Leone Charles A. 
Published: January 2023

Summary
Rabbits were injected with small amounts of the hemocyanins of Crustacea for four or five short series. Three animals were presensitized with antigen, and then given several series of injections after a period of rest of thirty days. The change in the content of antibody, and the change in the specificity of the antisera were observed after each series by means of a photoelectric, turbidimetric titration of the entire range of reaction between antigen and antibody. The amount of antibody in the antisera generally increases following each series of injections. However, decreases have been observed to occur following the third and fourth series. The specificity of antisera generally decreased during the course of immunization. However, increases in specificity following previous decreases in specificity also occurred. Presensitization seems to be equivalent to one or two series of injections in so far as the specificities of antisera are concerned. Relatively large dilutions of immune sera which are in the “maximal antibody-constant specificity” state do not increase their specificity. The specificity of an antiserum is primarily dependent upon the physiological state of the animal which produces it. Under uniform schedules of injection the specificities of antisera produced against the same antigen will vary from animal to animal. Thus, the specificity of an antiserum is not necessarily correlated with the amount of antigen involved in the immunization. The specific characteristics of the antigens, which are being compared, help to determine the specificity which is ascribed to an antiserum.
Comparison of the Antigenic Patterns of Influenza a Virus Strains Determined by in Ovo Neutralization and Hemagglutination-Inhibition
Authors: Hilleman Maurice R. , Horsfall Frank L. 
Published: January 2023

Summary
The ratio between the homologous in ovo neutralization and hemagglutination-inhibition titers of rooster antisera against influenza A virus strains varies widely. The hemagglutination-inhibition technique yields, in cross-serological experiments, somewhat less evidence of an antigenic difference between strains than does the in ovo neutralization procedure. Analysis of the antigenic relation between 2 strains by means of antiserum against 1 of the strains (r value analysis) may yield very misleading results, particularly if the hemagglutination-inhibition procedure is employed. Similar analysis by means of antisera against both strains (R value analysis) shows good correlation between the results obtained by hemagglutination-inhibition and by in ovo neutralization.
The results of complete cross-serological experiments carried out both by the in vivo and the in vitro procedures indicate that influenza A virus strains may show alteration in antigenic composition during successive annual epidemics. They indicate, also, that there is little evidence of antigenic difference between strains recovered in various parts of the world during 1951.
Immunochemical Studies on Tobacco Mosaic Virus
Authors: Malkiel Saul 
Published: January 2023

Summary
No appreciable difference was seen in the serological reaction between native tobacco mosaic virus and acetyl, p-chlorobenzoyl, carbobenzoxy, reduced carbobenzoxy, acetylglycine-treated, and benzal derivatives of the virus when tested with antiserum to the native virus.
Tobacco mosaic virus-azo-arsanilic acid produced no specific haptenic antibody in the rabbit when used as an antigen. The modified virus did react with an antiserum to a heterologous azo-arsanilic acid derivative.
The Role of Tubercle Bacilli in Adjuvant Emulsions on Antibody Production to Egg Albumin
Authors: Fischel Edward E. , Kabat Elvin A. , Stoerk Herbert C. , Bezer Ada E. 
Published: January 2023

Summary
Guinea pigs injected with crystalline egg albumin in an emulsion with the Freund adjuvants and containing killed tubercle bacilli showed substantially increased and prolonged antibody levels in their serum measured by the quantitative precipitin reaction as compared with guinea pigs injected with a similar emulsion lacking killed tubercle bacilli. The increased antibody formation was correlated with local granuloma formation and hyperplasia in the regional lymph nodes and spleens of animals receiving the emulsion containing killed tubercle bacilli.
General Preface to Studies on the Cultivation of Poliomyelitis Viruses in Tissue Culture
Authors: Enders John F. 
Published: January 2023

Abstract
These remarks are designed as a preface to a series of reports on the propagation of the viruses of poliomyelitis in tissue culture. To achieve clarity in presentation, the division of topics has been somewhat arbitrary. In consequence each report will contain data obtained through the application of phenomena or techniques described in certain of the other papers. Accordingly, it was thought that it might prove helpful to the reader to summarize here the content of the various papers and to indicate their principal interrelationships. It also seemed appropriate to review in a preface of this sort the literature relevant to the series as a whole as well as the earlier communications from this laboratory.
Since the demonstration by Landsteiner (1) in 1908 that poliomyelitis could be produced in monkeys, various workers have attempted to cultivate the causative agent in vitro.
On the Photolability of Serum Complement
Authors: Lundberg E. G. 
Published: January 2023

Summary
There has been shown by these experiments that: The light-destruction may be fairly well expressed by the monomolecular formula.The rate of the destruction is low, k varying from 0.019 to 0.050.The temperature-influence is small or none. μ certainly does not exceed two or three thousandths—which signifies an increase in k of 1.1 to 1.7 per cent for 1°C. increase of temperature at 27°C.Variation in lamp-distance causes changes in reaction-speed, which do not differ essentially from inverse proportionality to the light-intensity.Dilution of serum before radiating causes not only the expected decrease of complement strength, but also alters very irregularly its magnitude. It causes, too, an increase in reaction-speed, which, however, is not parallel to the dilution-amount.The color of serum changes obviously during radiation, from orange to dull yellow, the opalescence increasing at the same time. This is accounted for in the colorimetry.As regards the exactness of the measurements made with this method, the primary figures have a possible error of about ± 10 per cent. The graphically found values may be regarded as more exact (about 5 per cent possible error). The k- values are chiefly found to differ within ± 12 per cent from the mean, which may be regarded as quite satisfactory. The temperature-variation in each experiment—being within ± 0.4°—may be disregarded in consequence of the insignificant temperature-influence.
Studies on the Toxicity of Human Blood Plasma for Guinea-Pigs
Authors: Levinson S. A. 
Published: January 2023

Summary
Blood plasma obtained from pregnant women is more toxic for the guinea-pig on intravenous injection than plasma obtained from normal individuals. Human placental plasma is practically nontoxic. Similar relations are found with dog plasma obtained from pregnant dogs and from full term fetuses.
Plasma obtained during the menstrual cycle (before and after) is occasionally more toxic for guinea-pigs than normal female plasma.
The cause of death in the guinea-pig is an intravascular clotting of the capillaries of the lungs, with a resulting asphyxia, and occlusion in other capillaries as well (brain, liver, etc.). Death can be prevented if the animal is hirudinized, or if the amount of citrate simultaneously injected, is increased.
Studies on the Bactericidal Reaction
Authors: Adler Frank L. 
Published: January 2023

Summary and Conclusions
Sera from guinea pigs and rabbits of normal stock contain relatively thermostable antibodies which mediate the killing of apparently S-state cells of Salmonella typhosa by complement. The “normal” bactericidins appear to be specific for antigenic factors IX and XII, which are characteristic for the surface of S-state S. typhosa cells. An additional factor, present in all normal sera tested, depresses the bactericidal activity against S. typhosa O 901 cells and also interferes with the adsorption of the antibodies responsible for sensitization of S. typhosa O 901 cells to cells of antigenically related, apparently S-state, Salmonella species. It has been suggested that the inhibiting factor may be an antibody specific for an antigen which is prominent in determining the antigenic characteristics of the surface of R-state cells, but is also present, though less prominently, on the surface of apparently S-state Salmonella cells.
Antigens in Scarlatinal Erythrogenic Toxin Demonstrable by the Oudin Technic
Authors: Jennings Robert K. 
Published: January 2023

Summary
Dick toxin contains a mixture of antigens for which specific antibodies exist in the sera of horses immunized for the production of scarlatinal antitoxin. At least eight distinct precipitin systems are represented in a mixture of commercial antitoxin and standard erythrogenic toxin employed in this laboratory. Several methods of identifying individual precipitin systems, based on the Oudin technic, have been examined: Specific adsorption of one antibody from the serum gives the most unequivocal results. Replacement of the antigen layer on agar in which zones have been established is a reliable method, but produces some unexplained effects. Agreement between the slopes of lines representing the relation between concentration of antigen and rate of migration should be used only as supportive evidence when dealing with ill-defined preparations. At least one antigen present in Dick toxin, antigen A, is derived from the heart-infusion broth used in toxin production. The erythrogenic toxin proper is represented by the fourth zone (D) in tubes containing our standard toxin and antitoxin.
Anaphylactic Reactions and Concentrations of Antibody in Rats and Rabbits: Effect of Adrenalectomy and of Administration of Cortisone
Authors: Dews Peter B. , Code Charles F. 
Published: January 2023

Summary and Conclusions
The enhancing effect of adrenalectomy on anaphylaxis in rats has been confirmed. Part of this enhancement is caused by enhancement of the development of sensitivity by adrenalectomy which, however, does not appear to be due to an effect on concentrations of antibodies. Administration of cortisone, just prior to challenging, increased the resistance of adrenalectomized rats to anaphylactic shock although severe reactions still occurred. Administration of cortisone during sensitization of adrenalectomized rats reduced the development of sensitivity so that much milder anaphylactic reactions occurred.
Intact of adrenalectomized rats that received injections of cortisone produced slightly lower concentrations of hemolysins when rabbit erythrocytes were injected than similarly treated rats that did not receive cortisone.
Administration of cortisone to intact or adrenalectomized rabbits receiving daily intracutaneous injections of antigen lowered greatly the resulting concentrations of circulating antibodies and inhibited the development of cutaneous sensitivity. Adrenalectomy had some enhancing effect on cutaneous sensitivity.
Administration of cortisone produced no detectable effect on the concentration of circulating hemolysins produced in guinea pigs after either subcutaneous or intravenous injection of rabbit erythrocytes.
Immunization of Mice Against Histoplasma Capsulatum
Authors: Salvin S. B. 
Published: January 2023

Summary
A method was found for obtaining constant death rates in white Swiss mice. Immunization of mice for short periods of time was accomplished by intraperitoneal inoculation with dead yeastlike cells of Histoplasma capsulatum, the broth filtrate from the growth of the mycelium, or the broth filtrate from the growth of the yeastlike cells. Subsequent intracerebral challenge revealed protection against 300–400 LD50 of H. capsulatum. Cross protection between Blastomyces dermatitidis and H. capsulatum was not noticeable in the strains tested, when acetone-dried cells of the yeastlike phase were used as protective antigens.
The Hemagglutinin of St. Louis Encephalitis Virus
Authors: Chanock Robert M. , Sabin Albert B. 
Published: January 2023

Summary
The SLE hemagglutinin was rapidly destroyed, even at 1 C, in the very pH range that is optimum for its combination with chick erythrocytes. While this destruction did not occur at pH 7.9 over a period of several hours at 24 C, all activity was lost within 5 to 10 minutes at 37 C.
The pH range for hemagglutination of chick erythrocytes by freshly prepared hemagglutinin was pH 6.6 to 6.9 or 7.1, with maximum titers occurring in a range of 0.1 to 0.3 pH units. When no hemagglutination occurred in a certain pH zone, there was no evidence of combination between hemagglutinin and erythrocytes. After storage of the hemagglutinin at 4 C, the pH range first gradually broadened from 6.6 to 8.3, with maximum titers on occasion at pH 7.4 to 7.7, then shifted back to the acid side with hemagglutination occurring even at pH 6.4 and 6.5 after 5 to 9 months. The “shifting-pH-zone” phenomenon was almost completely stopped by freezing the hemagglutinin at −70 C.
Loss of hemagglutinin occurred when it was frozen at pH 7.2, but not at pH 8.0. Lyophilization at pH 8.0 was unsatisfactory. Chloroform destroyed the hemagglutinin within a few minutes, and acetone yielded a virtually insoluble precipitate from which no hemagglutinin could be recovered. Formalin in a final concentration of 0.1% destroyed the hemagglutinin within 24 hours at 4 C, but had no effect on the chick erythrocyte receptors at a final concentration of 0.25%.
Erythrocytes of all newly hatched chicks were regularly agglutinated in high titer, but the red cells of chickens gave lower titers or negative results. Chicken cells which were not agglutinated by the SLE hemagglutinin were agglutinated by the Japanese B hemagglutinin. Human group “O” and rhesus erythrocytes were not agglutinated, while sheep cells yielded titers that were lower than those obtained with chick cells, but higher than those obtained with pooled chicken cells. Hemagglutination with titers of the same order of magnitude occurred when the reagents were mixed at 3 or 25 C, and the red cells sedimented at one or the other temperature, but no hemagglutination occurred when the reagents were quickly brought to 37 C prior to mixing even if subsequent sedimentation was at 25 C.
For each twofold increase in concentration of erythrocytes, the hemagglutinin titer dropped threefold. When chick erythrocytes, which had been agglutinated at 25 C, were repeatedly resuspended, reversal of agglutination occurred first in the tubes with the smallest amount of hemagglutinin, and more rapidly with increasing temperature and decreasing pH. There was no destruction of receptors on the chick erythrocytes during reversal of hemagglutination. The enzyme system in cultures of cholera vibrio, which destroyed the receptors for influenza A virus on chick red cells, had no effect on the receptors for the SLE hemagglutinin.
Antigen-Antibody Precipitates in Solid Medium with Influenza Virus
Authors: Jensen Keith E. , Francis Thomas 
Published: January 2023

Summary
Techniques for studying the diffusion of antigens and antibodies in an agar medium have been applied to several strains of influenza virus.
When either rabbit hyper-immune or convalescent ferret sera were mixed with agar, introduced into small tubes and the virus preparations layered upon the solid mixture, bands of precipitate formed in the appropriate tubes. This phenomenon has been shown to be strain-specific and therefore was interpreted as being due to the union of virus antigens and corresponding antibodies.
The strain-specific lines of precipitate were also obtained when the virus antigens and antibodies were allowed to diffuse toward each other from depressions in agar contained by Petri dishes.
The Antigenic Variation of Influenza B Viruses. Demonstration of an Antigenic Spectrum by Use of Titer Ratios
Authors: Jordan William S. , Gaylin Sheldon G. 
Published: January 2023

Abstract
Soon after the identification of influenza B virus in 1940 (1, 2), B strains of different antigenic composition were described (3–5). When epidemic influenza B recurred in 1945–46, other antigenically different strains were isolated (6–9). Most of the new strains were but distantly related to the original Lee strain and the possibility existed that mouse passage had altered the antigenic pattern of the Lee virus (8). In general, strains recovered from the same epidemic (6, 7), or during the same year (8) showed similar antigenic behavior. But at least two antigenically distinct strains have been isolated from the same epidemic, one strain, passed only through eggs, being closely related to Lee (9).
The isolation of a number of new B strains in 1949–51 (10, 11) and the growing realization of the biologic significance of antigenic and other variations among influenza viruses (12, 13) prompted several studies of the antigenic relationships between various strains recovered since the first influenza B virus was described (14–17).
A Toxic Substance Associated with the Rickettsias of the Spotted Fever Group
Authors: Bell E. John , Pickens Edgar G. 
Published: January 2023

Summary
A toxic substance was demonstrated in yolk sac cultures of ten strains of the spotted fever rickettsia which were selected according to their virulence for guinea pigs, tick-host species, or etiologic relationship to the various diseases of the spotted fever group. These strains included the agents of Rocky Mountain spotted fever, boutonneuse fever, South African tick bite fever and Indian tick typhus.
Three variables are shown to affect the production of the toxic factor in yolk sac cultures of R. rickettsii. These variables were (a) incubation of infected eggs after death of the embryo, (b) dose of inoculum used to initiate the egg cultures, and (c) the length of the time of survival of the embryo after inoculation.
The toxin of R. rickettsii was found to be specifically neutralized by serums of spotted fever convalescent individuals or experimental animals. It was also found to be neutralized by serums of human beings or guinea pigs following their injection with spotted fever tick vaccine.
Growth Curves of Coxsackie Viruses in Mice, including the Temporal Development of Complement Fixing Antigens
Authors: Contreras Guillermo , Melnick Joseph L. 
Published: January 2023

Summary
The antigenically distinct Coxsackie (C) viruses, Conn.-5, Nancy and Ohio-1, multiply rapidly in the newborn mouse. Twelve hours after a small dose of virus is injected, virus is present to a titer of 10−6 or more. The yields of infective virus and complement fixation (C–F) antigen are higher when a large inoculation dose is used than when a small dose is given. Texas-1 and Easton-2 viruses have a comparatively slower rate of multiplication. Following the inoculation of a small dose of virus, about 36 hours is required to reach the same infective titer that Nancy virus attains in 12 hours. However the virus titers ultimately reached are about the same as for Conn.-5, Nancy and Ohio-1 viruses, and the C–F antigen titers are higher, regardless of the amount of virus inoculated. The decreasing susceptibility after birth of the mouse within the first week of life is most marked for Ohio-1, less so for Conn.-5 and Easton-2, and not significant for Texas-1, as measured by lengthening of the incubation period and yield of C–F antigen. Methods by which satisfactory C–F antigens may be obtained for several C viruses are described. Conn.-5 and Easton-2 viruses grow readily on the presence of each other.
A Consideration of the Components Concerned in the Conglutinating Activities of Certain Complements
Authors: Rice Christine E. 
Published: January 2023

Summary
Experimental data are examined which seem to indicate that four major components were involved in the conglutinating activity of horse and pig complements. As with those making up the hemolytic complex, two were heat-labile, two were heat-stable, one of the latter inactivated by zymosan, the other by hydrazine or ammonia. Larger amounts of hydrazine or ammonia were required to inactivate the conglutinative activities of horse and bovine complements than their hemolytic properties for sensitized rabbit red cells. The question of whether there are a “hemolytic” and a “conglutinative” C′4 as suggested by Blomfield is discussed.
Dextran—An Antigen in Man
Authors: Kabat Elvin A. , Berg Deborah 
Published: January 2023

Summary
Native and clinical dextrans derived from strains of microorganisms synthesizing products with different ratios of 1:6 to non 1:6 linkages have been found to be antigenic in man. Three weeks after injection of 1 mg of dextran, precipitins and cutaneous sensitivities of the wheal and erythema type develop. The antigenicity of dextran in man, its occurrence in commercial sugar and its elaboration by microorganisms in the gastrointestinal tract appear to provide an explanation for the occurrence of systemic allergic reactions in man on infusion of dextran and for the occurrence of small quantities of antidextran and of cutaneous sensitivity in individuals not previously injected with dextran. The precipitin reaction between dextran and antidextran is of the usual type. Differences in the behavior of various antisera with native and clinical dextran have been interpreted in terms of the structural similarities and differences among the preparations.