bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Hemagglutinin of West Nile Virus: Recovery, Properties, and Antigenic Relationships
Authors: Chanock Robert M. , Sabin Albert B. 
Published: January 2023

Summary
A specific hemagglutinin for chick erythrocytes was demonstrated in both unbuffered saline and pH 9 buffered saline extracts of the brain of 3 to 4 week old mice infected with the original (Uganda) strain of West Nile fever virus. In the unbuffered saline extracts (pH 7.1) much of the hemagglutinin was in large aggregates which sedimented at 13,000 rpm, while no such aggregates were present in the alkaline extracts (pH 8.1). Freshly prepared, 13,000 rpm supernates of the alkaline extracts produced hemagglutination between pH 6.7 and 7.5 or 8.0, but maximum titers (as high as 20,480) without zones of absent or poor agglutination in the lower dilutions were obtained at pH 7.1–7.3. After such preparations were stored at 4 C for 4 to 50 days the pH range shifted to the acid side with maximum titers at pH 6.7–6.9. The hemagglutinin in alkaline extracts was not destroyed by repeated freezing and thawing and could be maintained without loss of potency at -70 C.
To obtain the maximum titers it was necessary to mix the hemagglutinin with the red cells at 20 to 25 C and to permit sedimentation to occur at 4 C. With certain unbuffered saline extracts no reaction at all occurred when the reagents were at 4 C at the time of mixing, or if sedimentation occurred at 25 C. The reaction between the hemagglutinin and red cells is of the equilibrium type. Hemagglutination can be reversed by repeated resuspensions of the cells, because the uncombined hemagglutinin is unstable at the pH that is optimum for reaction. No receptor-destroying enzyme is involved because the addition of fresh hemagglutinin causes reagglutination of such cells.
When 3 other strains of West Nile virus (Egypt 19, 21, and 101) were tested no zone phenomena were encountered and fresh preparations yielded maximum titers at pH 6.7–6.9. Sedimentation at 4 C was needed to obtain maximum titers with strains 19 and 21 but not with 101. All 4 strains yielded identical hemagglutination-inhibition titers with specific antisera. The normal inhibitor present in human and animal sera was best eliminated by precipitating the specific antibody with acetone. Cancer patients experimentally infected with West Nile virus developed high titers of hemagglutination-inhibition antibody for the West Nile hemagglutinins and somewhat lower titers for the St. Louis and Japanese B virus hemagglutinins. Human beings naturally infected with the viruses of St. Louis or Japanese B encephalitis also developed hemagglutination-inhibition antibodies for all 3 viruses but the homologous titers were invariably higher. Hyperimmune rabbit sera for the 3 viruses showed much more extensive crossing by the hemagglutination-inhibition than by the neutralization tests. Hemagglutination-inhibition tests with West Nile, St. Louis and Japanese B hemagglutinins on “normal” Egyptian human sera gave positive results indicative of unrecognized infection only with West Nile virus.
The Incorporation of Radioactive Phosphorus into Influenza Virus
Authors: Liu Oscar C. , Blank Harvey , Spizizen John , Henle Werner 
Published: January 2023

Summary
Studies have been presented on the labelling of influenza virus with P32 during propagation in the allantoic cavity of chick embryos. The labelled virus has been purified routinely by 2 cycles of adsorption onto and elution from chicken red cells with intermittent dialysis against large volumes of phosphate buffered saline solution.
The degree of radioactivity of the virus progeny could be improved by an increase in the dose of P32 used, by prolongation of the interval between injection of the isotope and infection, and by a reduction in the age of the embryos employed. The ratio between counts per minute and hemagglutinin units of the yields could be increased further by the use of deembryonated eggs instead of intact chick embryos.
It has not been possible to separate the radioactivity from the virus particles by various biological, physical and chemical means.
Chemical fractionation of labelled virus revealed most of the radioactivity in the lipid and nucleic acid fractions.
Studies on the Mechanism of the Immunological Paralysis Induced in Mice by Pneumococcal Polysaccharides
Authors: Felton Lloyd D. , Kauffmann Gladys , Prescott Benjamin , Ottinger Barbara , Kauffmann Gladys 
Published: January 2023

Summary
Immunological paralysis has been defined as that condition produced in the host by an antigen given in such amount that a subsequent immunizing dose fails to stimulate active immunity. With the preparations of polysaccharide used in C3H mice the amounts included: For type I 500 μg or more, and for types II and III 50 μg or more. In white mice, one-tenth of these doses was sufficient to “paralyze” the defense. In both strains of mice, smaller amounts immunized the animal. The type-specific immunological paralysis persisted for at least 15 months following a single injection with type I or III polysaccharide and for 18 months with type II polysaccharide. For all three types studied, the reaction was essentially type-specific. Immunological paralysis was produced by 500 μg of type I polysaccharide by intraperitoneal, intravenous, or intradermal administration; but by the oral route the largest does given, 5.0 mg, immunized the mouse. For types II and III the 50 μg dose “paralyzed” the defense whether introduced intraperitoneally, intravenously, or intradermally; orally 5.0 mg immunized against type II, but not against type III infection. By subcutaneous route the “paralyzing” dose of 50 μg was the same for all three types. Repeated daily doses of smaller amounts “paralyzed” the defense when the total reached the above doses. With type I, this “paralysis” was not found in all mice; but with types II and III all mice so injected were unable to respond to a subsequent immunizing dose. Mice which had been previously immunized required four times as much antigenic polysaccharide to produce immunological paralysis as was required by normal mice. “Paralyzed” mice were found to be hypersusceptible to pneumococcus infection and required two to four times as much antibody to give passive protection as normal animals. The only successful means found for counteracting the “paralysis” in mice was the use of whole-cell vaccine, and this was applicable only to type I but not to types II and III.
A Study of Some Naturally Occurring Precipitins and Agglutinins of the Chicken: Reaction with Purified Blood Group Substances and Human Red Blood Cells
Authors: Baer Harold 
Published: January 2023

Summary
It has been found that the sera of some chickens can precipitate with purified blood group substances of porcine and human origin, the ability to precipitate being independent of the blood group activity of the substances. All chickens thus far studied possess agglutinins for human red cells. The agglutinins were found to be different from the precipitins but both had properties that indicate them to be antibodies.
Tissue Tropism of a Strain of Influenza a Virus in Ferrets
Authors: Sugg John Y. , Nagaki Daizo 
Published: January 2023

Summary
The study dealt with the occurrence of febrile reactions and with the multiplication of virus in different tissues of the respiratory tracts of ferrets following infection with the Cam strain of influenza A virus. All animals were infected by the intranasal route while under anesthesia. No evidence for multiplication of the virus in the lungs was obtained either during ten serial passages in ferret nasal mucosa, or during five passages in ferret lungs; the latter procedure was made possible by alternate passages in eggs. The results as a whole indicate that at least some strains of influenza A virus are non-pneumotropic agents in ferrets. The results also suggest that fever produced in ferrets by the intranasal inoculation of large amounts of influenza virus is related to the toxic properties of the virus particles rather than to processes involved in multiplication of the virus.
The Effect of Gamma Globulin on Subclinical Infection in Familial Associates of Poliomyelitis Cases
Authors: Brown Gordon C. , Rabson Alan S. , Schieble Jack H. 
Published: January 2023

Summary
A previous publication (1) described quantitative serial fecal virus isolations from familial associates of reported cases of poliomyelitis and demonstrated that most subclinical infections present at the time of gamma globulin inoculation were not eliminated nor was the amount of fecal virus reduced. The serological data presented in this report show that active immunization by subclinical infection is not inhibited by the administration of gamma globulin.
Neutralization tests with paired sera from 15 of 23 individuals with subclinical infection demonstrated significant increases in antibody titer to the specific immunological type of virus with which they were infected. The remaining eight had high levels of specific neutralizing antibody in the first sera with no subsequent elevations in titers.
Twenty-seven of thirty-two familial associates who remained uninfected already had specific neutralizing antibodies to the type of virus isolated from their respective family groups. These findings are in accord with previous observations which suggested that virus is less likely to become established in persons in whom antibodies are present prior to exposure.
Uninfected volunteers were inoculated with gamma globulin of known potency, and low levels of antibody were detected after three days to one week and persisted for only two to three weeks. These results eliminate the possible role of residual passive antibody on the titers obtained with sera collected six to eight weeks after gamma globulin administration to familial associates of poliomyelitis cases.
Pharyngeal virus isolations were successful in 6 of 25 individuals who had demonstrable alimentary infection. In all cases, the immunological types of the viruses from stool and pharyngeal secretions were identical. No viruses were isolated from sera nor from stools six months after their intestinal infection.
Development of Immunity in Mice after Vaccination with Inactivated Poliomyelitis Virus
Authors: Krech Ulrich 
Published: January 2023

Summary
The intraperitoneal inoculation of inactivated poliomyelitis virus type 2 into mice induces protection when given 3 days before intravenous infection.
The protection demonstrated is type specific, i.e., only the homologous antigen is effective.
A relationship between antigen concentration and proportion of survivors is demonstrated.
Pneumococcal Antigenic Polysaccharide Substances from Animal Tissues
Authors: Felton Lloyd D. , Prescott Benjamin , Kauffmann Gladys , Ottinger Barbara , Kauffmann Gladys 
Published: January 2023

Summary
Polysaccharide-containing fractions have been prepared from 12 organs and tissues of mice 2 to 3 weeks after injection of 0.5 mg of specific pneumococcus polysaccharide type I, II, or III, an amount known to produce immunological paralysis. The materials stimulated a high degree of immunity in mice against the homologous pneumococcus infection. Similar fractions prepared from tissues of normal mice were devoid of immunizing ability. Those from most tissues of immunized mice (after a 0.002-mg dose of specific polysaccharide) were found to stimulate a low degree of immunity.
Tests of similar polysaccharide-containing fractions from tissues of albino and C3H mice 8 to 9 months after a “paralyzing” injection of specific polysaccharide showed that but little type I antigenicity remained, and no type III, but that high titer immunity against type II could still be induced by the homologous polysaccharides isolated from both albino and C3H strains of mice.
In one experiment similar fractions prepared from organs and tissues of guinea pigs and rabbits injected with pneumococcal polysaccharides, especially type II, stimulated some immunity in mice against homologous pneumococcus infection.
Antibody Production by Spleen In Vitro
Authors: Mountain Isabel Morgan 
Published: January 2023

Summary
This study has provided new evidence that antibody can be formed in a culture of minced spleen from immunized rabbits. Rabbits were studied for H-agglutinin production after immunization with typhoid vaccine. Spleen removed four days after a single intravenous injection of vaccine served as the basis for the test system. Antibody production continued for as long as three days. The reproducibility of the test system was evaluated statistically in order to assay the effect of the addition of a variety of chemicals on antibody production.
Antibody formation in vitro required oxygen and was suppressed by sodium cyanide (10-2 through 10-4 M) and by salts of the heavy metals (at minimal concentrations indicated): manganous sulfate (10-3 M), ferric chloride (10-2 M), and cupric sulfate (10-4 M). Antibody formation in vitro was also suppressed in the presence of 100 mM sucrose and by the “essential” amino acids at 30 mM (combined total concentration) and by the reducing substances: reduced glutathione (15 mM), cysteine (15 mM or lower), and ascorbic acid (15 mM or lower) as well as by cortisone (32 mg %). With the exception of glutathione, and possibly sucrose, none of these substances (at concentrations which were found to be inhibiting) altered the antibody titer when incubated with immune serum. Thus, the various chemicals acted by inhibition of some phase of antibody formation by surviving cells in culture rather than by destruction of antibody once formed.
Effect of Oxytetracycline (Terramycin) on Agglutinin Titers in Guinea Pigs with Experimental Brucellosis
Authors: Carpenter Charles M. , Nelson Eric L. , Klein Sidney J. , Rawlings Bruce E. , Boak Ruth A. , Weimer Henry E. 
Published: January 2023

Summary
A marked decline in agglutinin titers was observed in guinea pigs with experimental brucellosis treated with oxytetracycline.
The decline in titer did not result from the drug's interference with the host's mechanism to form antibodies.
The Preparation and Properties of Fractions of Pig Complement. II
Authors: Leon Myron A. , Plescia Otto J. , Heidelberger Michael 
Published: January 2023

Summary
Two new fractions of complement have been isolated from pig serum containing C′1, C′3, and C′4, and C′1 and C′3, respectively. Probably because of their C′3 content, these fractions greatly enhance the lytic activity of gpC′. The maximal velocity of the reaction between EAC′1,4,2 (C′ cells) and the 1,3,4 fraction is directly proportional to the quantity of 1,3,4 added at constant EAC′1,4,2 concentration, and directly proportional to the EAC′1,4,2 concentration at constant 1,3,4 concentration. The concentration of C′3 was not appreciably diminished in the hemolytic reaction as carried out in these experiments.
Immunoelectrophoretic Studies on Serum Proteins
Authors: Williams Curtis A. , Grabar Pierre 
Published: January 2023

Summary
Immunoelectrophoretic analysis by horse or rabbit antibodies of human γ-globulin suggests antigenic homogeneity, or at least a high degree of antigenic correspondence, over a broad range of electrophoretic mobilities.
Quantitative electrophoretic homogeneity and qualitative immunological purity are not necessarily of the same significance. A fraction such as γ2-W, which contains several non-γ impurities, may show a quantitative homogeneity of the same order as that of II-Sq, which is comprised uniquely of γ-globulin with asymmetric electrophoresis dispersion.
Subfractionation of a preparation of II-Sq into water soluble and water insoluble material at pH 7.2, and the separation of serum euglobulin from fresh serum gave evidence for the existence of complexes among human serum antigens, or for their formation by the fractionation procedures. The γ-globulins of different solubility appeared to have the same antigenic specificity.
The significance of serum complexes is discussed in relation to the nature and function of γ-globulin.
Influenza Virus Infection of Transplanted Tumors
Authors: Wagner Robert R. 
Published: January 2023

Summary
Transplantation of Sarcoma 37, infected in vitro with neurotropic-WS influenza virus (NWS), to virus-immune mice resulted in rapid disappearance of infective virus from the grafts and unimpaired tumor growth. NWS virus, present as a “passenger” in attenuated sarcomas, was also rapidly neutralized after transplantation of the tumors to vaccinated animals. Neoplasms thus released from the tumor-suppressive action of the virus slowly recovered their normal growth potentials.
Administration of antiviral antibody, in the form of hyperimmune rabbit serum, to animals bearing infected Sarcoma 37 transplants completely neutralized the infectivity and tumor-inhibitory effect of NWS virus. The infectivity of the virus was not restored by retransplantation of these tumors to normal mice.
Passive immunization produced a somewhat slower decline in the infective titer of NWS virus in Brown-Pearce carcinoma transplants.
Infection of Sarcoma 37 grafts with the tumor-adapted FWS influenza virus also responded to treatment with homologous immune serum.
In contrast to neoplastic tissue, passive immunization did not alter significantly the course of NWS virus infection of adult mouse brain and lung or subcutaneous homografts of mouse fetal lung and kidney.
The results of these experiments will be discussed in conjunction with the studies on the Ehrlich ascites tumor presented in the following paper.
Incidence of Antibodies to Salmonellae among the Population of the Bronx, N. Y.
Authors: Weil A. J. , Saphra Ivan 
Published: January 2023

Summary
Among the population of the Bronx, N. Y., a low incidence of agglutinating antibodies was found in tests including the following Salmonella antigens: groups B, C1, C2, and D, and flagellar b, d, i, and 1, 5.
The implications of these findings are discussed.
Purification and Some Properties of Clostridium Welchii Type A Theta Toxin
Authors: Roth Florence B. , Pillemer Louis 
Published: January 2023

Discussion and Summary
Theta toxin has been highly purified by fractionation of filtrates of Clostridium welchii type A in methanol-water mixtures under controlled conditions of pH, ionic strength, protein concentration, and temperature. By means of six fractionation steps, a product containing 2,450,000 theta hemolytic units per mg of protein nitrogen was obtained. This preparation was free of collagenase and hyaluronidase and contained less than 0.01% of the total amount of lecithinase activity of the parent filtrate. As judged from electrophoretic analysis, a value of 2,650,000 theta hemolytic units per mg of protein nitrogen was calculated for pure theta toxin.
The degree of purification depended upon the potency of the parent filtrate and upon the relative ratio of theta toxin hemolytic activity to lecithinase Lb activity which it contained.
Although no substrate other than the red blood cell has yet been found for theta toxin, certain of the properties of the purified hemolysin indicate that it might act enzymatically. The exceedingly small amount of activated hemolysin which produces lysis suggests its action is catalytic. About 2.5 × 10-6 mg of protein represents one hemolytic unit. This amount of hemolytically active protein lysed 6 ml of a 0.25% suspension of sheep red blood cells in 30 minutes at 37°C. It is improbable that such a small amount of protein could alter this concentration of red cells other than by catalytic action. The protein nature of theta hemolysin, its activation by —SH compounds, its pH and temperature dependence, also suggest that theta toxin is an enzyme. The manner in which activated theta toxin brings about hemolysis of red cells could be explained by the enzymatic attack of some constituent of the red cell membrane. However, the identity of this constituent is not known. Positive proof that theta toxin is an enzyme must await the identification of its specific substrate.
Murray Valley Encephalitis Virus: Its Serological Relationship to the Japanese-West Nile-St. Louis Encephalitis Group of Viruses
Authors: Pond William L. , Russ Sudie B. , Rogers Nancy G. , Smadel Joseph E. 
Published: January 2023

Summary
An agent isolated by Australian workers in 1951 and designated as Murray Valley encephalitis virus has been characterized antigenically by the means of neutralization and complement-fixation tests and cross vaccination experiments. The MVE virus appears to be a new member of the JE-WN-SLE group of agents, more closely related antigenically to JE than to WN and SLE.
Results of neutralization tests on sera of Japanese Nationals suggest that MVE virus is absent from Japan, or that it infects fewer people than JE virus. Although half the sera tested contained MVE antibodies, these were invariably obtained from persons with large amounts of JE antibody and the MVE effect could probably be attributed to prior JE infection.
When 14 strains of supposed JE virus isolated in the Far East were re-examined in neutralization tests with JE and MVE immune rabbit sera of known specificity, all strains reacted as JE and none could be re-designated as MVE virus.
Studies on Organ Specificity
Authors: Rose Noel R. , Witebsky Ernest 
Published: January 2023

Summary
Antisera produced in rabbits by injection of crude extracts of thyroid glands gave crossreactions with thyroid extracts of various species in an irregular and unpredictable manner, thus exhibiting a pattern similar to that observed by Hektoen, Fox, and Schulhof (1) with isolated thyroglobulins. Basically, identical results were obtained by complement-fixation and precipitation techniques. Antisera produced in dogs by the injection of the same crude thyroid extracts also contained thyroid-specific antibodies. Cross-reactions with thyroid extracts of other species were considerably less prominent than in the case of rabbit antisera. There is a considerable variation in the extent of cross-reaction, depending upon the individual animal used for immunization. This observation makes general statements about the degree of cross-reaction most difficult. Absorption with human serum of a human thyroid antiserum containing antibodies against human serum as well as thyroid extracts of different species resulted in the elimination of the species-specific antibody without influencing the thyroid-specific antibodies. Absorption of the same antiserum with human thyroid extract (the homologous antigen) resulted in removal of the entire antibody content of the serum. Absorption with hog thyroid extract eliminated the cross-reaction with both hog thyroid and beef thyroid extract but did not reduce the strong reaction with the homologous human thyroid extract. These findings were substantiated by both complement-fixation and precipitation tests. The extent of cross-reactions of thyroid antisera with thyroid extracts of different species was estimated by diluting in the same experiment both antigen and antiserum. Cross-reactions with the thyroid extracts of different species were considerably weaker than the reactions with homologous antigen. There is also an important time element in the evaluation of serological reactions of this type. In complement-fixation tests, cross-reactions obtained with the thyroid of heterologous species disappeared rapidly after further incubation at 37°C, whereas the reaction with the homologous antigen did not decrease significantly. In precipitation tests, the homologous reactions appeared first, while the crossreactions manifested themselves after further standing. The cross-reactions of thyroid antisera with thyroid extracts of other species are thyroid-specific. No reactions were detected with other organs of the heterologous species.