bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of the immunoprotective antigen of ribosomal preparations from Haemophilus influenzae
Authors: Tewari R P , Lynn M , Birnbaum A J , Solotorovsky M
Published: January 2020

This investigation was designed to characterize the immunoprotective antigen of ribosomal preparations from Haemophilus influenzae. The ribosomes that elicited 80 to 90% protection contained 25% protein and 75% ribonucleic acid but did not contain any detectable hexoses. The immunodiffusion and hemagglutination inhibition tests also failed to demonstrate that the capsular material (polyribose phosphate) was in ribosomal preparations. Treatment of ribosomes with ribonuclease degraded 78% ribonucleic acid but did not affect the immunogenicity of such preparations. The proteolytic enzymes reduced the immunogenicity of ribosomes corresponding to the amount of protein degraded. The protection elicited by ribosomal protein extracted with 2-chloroethanol was comparable to that induced by intact ribosomes. In contrast, the low levels of protection observed by immunization with phenol-extracted ribonucleic acid were dependent on the amounts of contaminating protein. Finally, immunogenicity of ribosomal ribonucleic acid and protein was abrogated by treatment with proteolytic enzymes. These results clearly indicate that the protein associated with Haemophilus ribosomes is the major immunoprotective antigen.
Solid-phase radioimmunoassay method for determination of Escherichia coli enterotoxin
Authors: Ceska M , Grossmüller F , Effenberger F
Published: January 2020

The development of a solid-phase radioimmunoassay procedure for the determination of Escherichia coli enterotoxin(s) is described. Radioiodinated E. coli enterotoxin with about three radioiodine atoms per toxin molecule is, by the criterion of electrophoresis, identical to the unlabeled toxin. Goat anti-E. coli-enterotoxin antibody was coupled to polystyrene tubes and served as a solified toxin binder in the reported procedure. Various conditions necessary for the optimization and standardization of the solid-phase method were established. With the help of this technique it was possible to determine E. coli enterotoxin released from a porcine E. coli strain into culture medium.
Lipid A-induced tolerance and hyperreactivity to hypothermia in mice
Authors: Greer G G , Rietschel E T
Published: January 2020

Mice responded to lipopolysaccharide (LPS) with a dose-dependent, monophasic hypothermia reaching a maximum at 2 h postinjection. Degraded polysaccharide was not active; free lipid A, however, induced a similar pattern of hypothermia, indicating that the hypothermic principle of LPS was embedded within the lipid A component. The hypothermic response of mice to LPS was modified by prior exposure of the host to LPS. This altered reactivity was manifested by refractory periods (early and late tolerance), in which animals no longer responded with hypothermia, or a hyperreactive phase (hypersensitivity), in which hypothermic responses were greatly augmented upon LPS challenge. Thus, tolerance observed 24 h after a single injection of LPS (early tolerance) was followed, on further LPS challenge, by an enhanced hypothermic responses reaching a maximum on day 4. Further daily exposure of the animals to LPS eliminated hyperreactivity and led to the establishment of a late tolerance maximally expressed on day 8. Hyperreactivity could also be evoked on day 4 after a single injection of LPS. Mice pretreated with Salmonella S- and R-form LPS or free lipid A (Salmonella) demonstrated tolerance and hyperreactivity to both homologous and heterologous challenge. In addition, complete cross-tolerance was observed with S-form LPS derived from Shigella. It was concluded that the differential effects of LPS on host responses (tolerance and hyperreactivity) were due to lipid A.
Suppression of antibody response by group A streptococcal pyrogenic exotoxin and characterization of the cells involved
Authors: Cunningham C M , Watson D W
Published: January 2020

The effect of purified streptococcal pyrogenic exotoxins (SPE) on the antibody response to sheep erythrocytes was studied in cultures of mouse spleen cells. Purified SPE types A, B, and C shared the ability to suppress the day 4 direct plaque-forming cell response when added to cultures. SPE A and C were most suppressive at concentrations of 0.1 to 1 ng per culture, while SPE B was active at 1 microgram per culture. Pretreatment of mice with SPE A, 3 h before removal of their spleens for culture, also produced suppression. Cell populations were separated from spleens of normal and toxin-treated mice and recombined in culture to test the cellular site of action of SPE immunosuppression. When nonadherent cells (lymphocytes) and adherent cells (macrophages) from control and SPE-treated mice were separated and recombined, the plaque-forming cell response depended on the source of lymphocytes. Macrophages from toxin-treated mice functioned normally in the presence of control lymphocytes. In a further experiment, toxin pretreatment failed to suppress the plaque-forming cell response of spleen cells that were T-cell depleted and reconstituted with control thymocytes. When the T lymphocytes were removed from toxin-treated spleen cell suspensions, the remaining cells were able to respond normally to antigen if normal helper T cells were provided. The results suggest that the suppressive activity of SPE on antibody production is mediated by altered activity of T lymphocytes.
Friend virus-induced immunodepression: effect of neuraminidase treatment on Thy-1.2 antigen expression and cytotoxic potential of splenocytes from virus-infected mice
Authors: Mascio A A , Ceglowski W S
Published: January 2020

Infection of susceptible strains of mice with Friend leukemia virus (FLV) results in a profound depression of cell-mediated immunity as assessed by lymphocyte-mediated cytotoxicity. This depression occurs early in the disease, before the onset of splenomegaly, and is associated with a decline in the susceptibility of splenocytes from FLV-infected mice to lysis by anti-Thy-1. 2 serum and complement. Treatment of splenocytes from FLV-infected mice with neuraminidase restores, in large part, their susceptibility to anti-Thy-1.2 serum as well as their cytolytic capacity. These studies suggest that one early immunosuppressive consequence of infection with FLV involves alteration of the effector T-lymphocyte cell surface.
Granuloma formation by synthetic bacterial cell wall fragment: muramyl dipeptide
Authors: Emori K , Tanaka A
Published: January 2020

A synthetic muramyl dipeptide, N-acetylmuramyl-L-alanyl-D-isoglutamine, which possesses the same structure as that of a part of the peptidoglycan monomer of wax D of tubercle bacilli or bacterial cell walls was found to induce, when injected in water-in-oil emulsion, massive granulomas often accompanying abscesses in the site of injection and draining lymph nodes of guinea pigs and rats. The granulomas were composed mainly of epithelioid cells 2 weeks after injection and were indistinguishable from those induced by tubercle bacilli. The granulomas induced in rats were less mature than those induced in guinea pigs. Allergic reaction appeared to play no important role in the development of the muarmyl dipeptide-induced granuloma.
Detection of cholera enterotoxin activity in suckling hamsters
Authors: Takeda T , Takeda Y , Miwatani T , Ohtomo N
Published: January 2020

For detection of cholera enterotoxin activity, suckling hamster, mouse, and rat models were compared. It was found that not only suckling mice but also suckling rats and hamsters were sensitive to cholera enterotoxin. Among these models, suckling hamsters were the most sensitive and gave positive results with about 1/100 the cholera toxin seen in suckling mice and rats.
Characterization of a partially purified methanol-soluble heat-stable Escherichia coli enterotoxin in infant mice
Authors: Mullan N A , Burgess M N , Newsome P M
Published: January 2020

While studying the involvement of cyclic adenosine 3',5'-monophosphate (cAMP) in the fluid secretion caused by heat-stable enterotoxin (ST) from Escherichia coli P16 in infant mice, it was noted that the culture filtrate containing ST also contained large amounts of cAMP. The present paper details attempts to obtain a cAMP-free ST preparation. The organisms were grown in a defined medium, and the heated culture filtrate was concentrated by reverse osmosis. After methanol extraction of the filtrate, which removed 80% of the nonactive solids, the methanol-soluble ST was further purified by gel filtration through a Sephadex G-10 column. The first fraction recovered after gel chromatography contained ST with a negligible amount of cAMP. Treatment with methanol did not adversely affect the enterotoxic activity. Certain parameters of the infant mouse model have been investigated, and using our ST preparation it has been found that animals remain responsive up to 15 days of age with an optimum assay time of 2 h after toxin challenge.
Role of activated macrophages in resistance of congenitally athymic nude mice to hepatitis induced by herpes simplex virus type 2
Authors: Mogensen S C , Andersen H K
Published: January 2020

Congenitally athymic nude (nu/nu) mice of a BALB/c genetic background were found considerably more resistant to the induction of focal necrotic hepatitis by herpes simplex virus type 2 (HSV-2) tha, were phenotypically normal littermates (nu/+) or BALB/c mice. The augmented resistance was age dependent, as it was only manifested in mice from 4 to 5 weeks of age. Studies of the course of infection showed that nude mice were able to restrain virus multiplication in the liver far better than normal mice in the early phase of infection. However, they seemed inferior to normal mice in eliminating the infectious process. In vitro investigation of peritoneal macrophages revealed that macrophages from 6-week-old nude mice exhibited accelerated spreading and were three times as restrictive in the replication of HSV-2 as macrophages from normal mice. However, no difference was found in the efficiency of adsorption/phagocytosis between macrophages from nude and normal mice. The increased resistance of nude mice could be abolished by blockade of the microphage function of the mice by silica. Nude mice reconstituted at birth with thymus cells were just as susceptible to infection as normal mice. These data suggest that the increased resistance of nude mice to HSV-2 hepatitis is due to the presence of nonspecifically activated macrophages before infection.
Effects of fatty acids on motility retention by Treponema pallidum in vitro
Authors: Matthews H M , Jenkin H M , Crilly K , Sandok P L
Published: January 2020

Treponema pallidum (Nichols virulent strain) was incubated under 75% N2 + 20% H2 + 5% CO2 in prereduced serum-free modified Eagle-Richter medium supplemented with different concentrations of various long-chain fatty acids complexed with fatty acid-free bovine serum albumin. Motility retention was greater in medium with oleic acid containing 15 rather than 2 mg of albumin per ml. Palmitic, stearic, oleic, or linoleic acid alone caused rapid loss of motility at concentrations as low as 5 microgram/ml. Elaidic acid (92 microgram/ml) alone had no effect on motility. Various combinations of saturated plus unsaturated fatty acids did not inhibit motility retention or were less inhibitory than either of the individual fatty acid components. The combination of palmitic plus oleic acids was least toxic. Rapid loss of motility occurred with pairs of unsaturated or saturated fatty acids, or with Tween 40, 60, or 80, alone or combined. Autoxidation of oleic acid resulted in decreased toxicity for T. pallidum but increased toxicity for baby hamster kidney cells.
Effect of Chemoattractants on Chemiluminescence
Authors: Allred Craig D. , Hill Harry R.
Published: January 2020

Upon ingestion of particulate matter, polymorphonuclear leukocytes produce a chemiluminescence that can be measured in a liquid scintillation counter. In the experiments reported here, the influence of three chemoattractants and three chemotactic modulators upon the chemiluminescence induced by opsonized zymosan was studied. The chemoattractants investigated (including bacterial factor derived from
Escherichia coli
, the simple peptide formylmethionylalanine, and activated human complement), which initiate directed movement when presented to cells in a concentration gradient, significantly enhanced zymosan-induced chemiluminescence. In the absence of opsonized zymosan, however, they had no effect on the chemiluminescence response. In contrast, the chemotactic modulators studied (including carbamylcholine, phenylephrine, and cyclic guanosine 5′-monophosphate, which are not chemotactic by themselves but can enhance or depress the movement of polymorphonuclear leukocytes initiated by chemoattractants) produced no enhancement of chemiluminescence. Other experiments were carried out in which neutrophils were pretreated with cytochalasin D, a compound that inhibits phagocytosis by interacting with microfilaments. Under these conditions, the chemiluminescence induced by opsonized zymosan was markedly reduced, but the response resulting from the addition of a chemoattractant to the leukocyte/zymosan mixture was not. This indicates that the chemiluminescence in response to chemoattractants is not dependent on phagocytosis per se. Neutrophils were also pretreated with dinitrofluorobenzene, a compound that binds amino groups and can be expected to react with proteins on the cell membrane. In these experiments, the chemiluminescence induced by opsonized zymosan and the pronounced spike of activity produced by the addition of a chemoattractant were completely abolished. These results suggest that the polymorphonuclear leukocyte chemiluminescence response to chemoattractants is mediated by cell surface proteins. Thus, chemoattractants may have a dual role in the acute inflammatory response: (i) the initiation and maintenance of directed cell movement, and (ii) enhancement of metabolic steps mediated at the cell membrane, resulting in microbicidal activity.
Effects of antibiotic resistance plasmids on the bactericidal activity of normal rabbit serum
Authors: Reynard A M , Beck M E , Cunningham R K
Published: January 2020

The ability of normal rabbit serum to kill Escherichia coli J6-2 was measured. With the concentration of serum adjusted so that approximately 2% of the cells survived after 2 h of incubation, there was no killing of the same strain bearing the F-like plasmid R100. Other F-like plasmids also provided the host strain with resistance to serum bactericidal activity, whereas none of the I-like plasmids used provided the host strain with resistance. When E. coli J6-2 bore both R100 and an I-like plasmid, there was some resistance to serum but less than with R100 alone. The effects of lysozyme on E. coli J6-2, which had been treated with tris(hydroxymethyl)aminomethane and ethylenediaminetetraacetate, were not altered by the presence of R100. The plasmids from 16 clinical E. coli isolates were transferred to J6-2N, a nalidixic acid-resistant mutant of J6-2. Four of the 16 plasmids provided J6-2N with resistance to normal rabbit serum.
Production of enterotoxin by Yersinia enterocolitica
Authors: Pai C H , Mors V
Published: January 2020

Forty-three strains of Yersinia enterocolitica isolated from children with gastroenteritis and 18 laboratory strains were examined for enterotoxin production by using the infant mouse, Y1 adrenal cell, and rabbit ileal loop assay systems. All clinical isolates and seven laboratory strains were found enterotoxigenic in the infant mouse model, but none of the strains produced toxin in the Y1 adrenal cell system. One enterotoxin-producing strain was also tested by the rabbit ileal loop assay, confirming the results of the infant mouse assay. The enterotoxin was heat-stable and as active in the 6-h rabbit ileal loop as in the 18-h assay, suggesting a similarity to the heat-stable enterotoxin of Escherichia coli.
Rat model of experimental endocarditis
Authors: Santoro J , Levison M E
Published: January 2020

A simple model of infective endocarditis was produced in rats. With the aid of a guide wire, polyethylene catheters were passed into the left ventricle through the right carotid artery of Sprague-Dawley rats weighing 300 to 350 g. A volume of 1 ml of an overnight culture of Streptococcus mitis, Staphylococcus aureus, or Streptococcus faecalis was intravenously injected 1 to 2 days after catheterization. Bacterial titers of Streptococcus mitis in vegetations were about 10(4)-fold greater than in other tissues. Blood cultures were always positive after 6 h. Mortality was 19% at 1 week and 82% at 2 weeks. Catheters were pulled 24 h after infection, and vegetation titers of greater than 7.0 log10 colony-forming units per g were sustained at 5 days. In intravenously infected rats without catheters, blood and tissues were sterile after 3 to 5 days. With Staphylococcus aureus, vegetations had greater than 9.0 log10 colony-forming units and with Streptococcus faecalis 8.8 +/- 0.3 log10 colony-forming units per g at 2 days. The rat model of infective endocarditis should prove to be suitable for further pathological and therapeutic studies.
Heterophil antigen in bovine sera detectable by immune adherence hemagglutination with infectious mononucleosis sera
Authors: Lennette E T , Henle G , Henle W , Horwitz C A
Published: January 2020

Bovine sera for tissue culture use were shown to contain heterophil antigen of the Paul-Bunnell-Davidsohn type by immune adherence hemagglutination tests with sera from patients with infectious mononucleosis. The antibody titers observed were comparable to those determined by two other methods; i.e., the immune adherence hemagglutination test was found to be as specific as the differential absorption test with horse erythrocytes or the ox cell hemolysis assay,but it appeared to be the most sensitive of the three procedures. All 16 individual or pooled bovine serum samples showed Paul-Bunnell-Davidsohn antigen at concentrations varying over a fourfold range. The potential usefulness of the immune adherence hemagglutination test for various Paul-Bunnell-Davidsohn antigen-related problems and implications of the observations are discussed.
Decreased Growth Capacity of Passaged Gross Virus-Induced Mouse Lymphomas After Incubation with Antithymocytic Sera
Authors: Vredevoe Donna L. , Hays Esther F.
Published: January 2020

AKR or C3H/HeJ transplanted mouse lymphomas, originally induced by Gross virus, could be neutralized by in vitro incubation with an immunosuppressive rabbit anti-mouse thymus cell serum. Neutralization was measured by significantly increased latent periods or decreased incidence (at a minimum of 90 days post-transfer) of lymphoma in syngeneic recipients of lymphoma cells incubated with antithymocytic serum when compared with syngeneic recipients of lymphoma cells incubated with normal rabbit serum.
Effect of Formalin Treatment on Electrophoretic Mobility of Cholera Toxin
Authors: Esposito Vito M. , Feeley John C.
Published: January 2020

Crude cholera toxin detoxified by treatment with Formalin showed an increased mobility and a decrease in the number of detectable protein constituents when compared with the parent toxin by disc electrophoresis. The significance of these observations in relation to the enhanced antigenic activity of cholera toxoid as compared to parent toxin is discussed.
Complement in Endotoxin Shock: Effect of Complement Depletion on the Early Hypotensive Phase
Authors: From A. H. L. , Gewurz H. , Gruninger R. P. , Pickering R. J. , Spink W. W.
Published: January 2020

The complement (C) inhibition caused by bacterial endotoxin is well known, but the relationship of this reaction to endotoxin shock is unclear. Anesthetized dogs were therefore given
Escherichia coli
endotoxin intravenously with or without prior C depletion by a purified cobra venom factor (CVF). Mean aortic blood pressures (MAP) and C levels were measured. Intravenous CVF usually caused an early transient drop of MAP and a profound, long-lasting drop in C. Bacterial lipopolysaccharide (LPS) alone always caused a sudden (within 2 min) drop in MAP which was followed by partial recovery and then more long-lasting depression. Moderate drops in C usually occurred. In animals pretreated with CVF so that C levels were markedly depressed (<25% of control), LPS did not elicit the immediate MAP drops; however, a later (after 5 to 20 min) MAP drop always occurred. CVF pretreatment did not modify LPS-induced mortality. CVF effects were not caused by LPS contamination. These data show that the early hemodynamic responses of the dog to LPS may be mediated through the complement system.
Measurement of Candidacidal Activity of Specific Leukocyte Types in Mixed Cell Populations I. Normal, Myeloperoxidase-Deficient, and Chronic Granulomatous Disease Neutrophils
Authors: Lehrer Robert I.
Published: January 2020

Candida albicans
cells which survive ingestion and multiply within phagocytes develop characteristic filamentous pseudogerm tubes.
Candida
cells killed by phagocytic leukocytes develop prominent alterations in Giemsa-staining characteristics; this reflects degradation of cyanophilic cytoplasmic components, probably ribonucleic acids. The numbers of these partially degraded organisms, termed “ghosts,” correlate closely with the percentage of
Candida
determined by an independent method to be nonviable. An assay, which makes use of these changes in morphological and staining characteristics of ingested
C. albicans
, was developed to evaluate the candidacidal activity of peripheral blood phagocytes. Neither myeloperoxidase-deficient neutrophils nor those from patients with chronic granulomatous disease killed
C. albicans
effectively, confirming observations made previously. Whereas myeloperoxidase-deficient cells were able to retard the intracellular germination of
C. albicans
, neutrophils from patients with chronic granulomatous disease lacked this ability. The candidacidal activity of monocytes and eosinophils in small samples of peripheral blood can also be measured by the new assay.
Preparation of Cell Wall Antigens of
Staphylococcus aureus
Authors: Kowalski J. J. , Tipper Donald J. , Berman David T.
Published: January 2020

Cell walls were prepared from
Staphylococcus aureus
strains Copenhagen and 263 by high-speed mixing in the presence of glass beads followed by differential centrifugation. Insoluble peptidoglycan complexes were derived from cell walls by extraction of teichoic acid with 10% trichloroacetic acid. Intact teichoic acid was prepared from each strain by digestion of cell walls with lysostaphin and isolated by column chromatography. Soluble glycopeptide (peptidoglycan in which only the glycan has been fragmented) and the stable complex of teichoic acid with glycopeptide were prepared by digestion of cell walls with
Chalaropsis
B endo-
N
-acetylmuramidase and were separated by column chromatography. Amino acid and amino sugar contents of walls and subunits of walls were comparable to those reported by others.
Uptake of Cystine by the Yeast Phase of
Histoplasma capsulatum
Authors: Gilbert Brian E. , Howard Dexter H.
Published: January 2020

This report deals with factors affecting the uptake of cystine by the yeast phase of
Histoplasma capsulatum
. The kinetics of uptake showed a saturation at 70 μM and an average
K
m
value of 3 × 10
−5
m
. The optimal
p
H and temperature for transport of cystine were 6.5 and 37 C, respectively. The energy of activation was 14.1 kcal/mole, and the temperature coefficient value was 2.1. A requirement for energy supplied by metabolic activity was demonstrated by the inhibition of incorporation of the amino acid by cells preincubated with either 2,4-dinitrophenol or sodium azide. Although uptake was not inhibited by any single amino acid, a combination of amino acids did cause a decrease in uptake. Thus, the data show that the uptake of cystine by yeast cells of
H. capsulatum
has the characteristics of a system of transport that requires the expenditure of energy by the cells.
Distribution of Echovirus Antibody in Serum, Nasopharynx, Rectum, and Spinal Fluid After Natural Infection with Echovirus Type 6
Authors: Ogra Pearay L.
Published: January 2020

By employing the techniques of radioimmunodiffusion and autoradiography and by using
32
P-labeled echovirus 6 as the antigen, the distribution of echovirus 6 antibody in serum, nasopharynx, rectum, and spinal fluid was studied in a group of children with naturally acquired echovirus type 6 infection, with or without meningeal involvement. The response in serum was characterized by sequential appearance of γM, γG, and rarely of γA antibody. The secretory response in the nasopharynx and rectum was limited to secretory γA immunoglobulin. The response in spinal fluid was limited to γG immunoglobulin. γG echovirus antibody appeared in the spinal fluid with or without demonstrable replication of virus in the spinal fluid. It is suggested that, after short-term acute infection with enteroviruses, the appearance of γG antibody in spinal fluid may largely be a reflection of increased transport of serum antibody, particularly of γG immunoglobulin class.
Oral Immunization in Experimental Salmonellosis II. Characteristics of the Immune Response to Temperature-Sensitive Mutants Given by Oral and Parenteral Routes
Authors: Fahey K. J. , Cooper G. N.
Published: January 2020

A temperature-sensitive mutant of
Salmonella enteritidis
, selected because of its inability to proliferate normally at 37 C, has been used as a living vaccine in mice. When given parenterally or orally, it confers a high degree of resistance against otherwise lethal
S. enteritidis
infections given intraperitoneally or by mouth. In contrast to most other effective living
Salmonella
vaccines, the temperature-sensitive mutant survives for only short periods in mouse tissues. Although the vaccine provides protection against
S. typhimurium
infection, possibly because of antigenic relationships between the immunizing and challenge organisms, it is ineffective against the intracellular infection caused by
Listeria monocytogenes
. A study of the kinetics of
S. enteritidis
infection in the liver and spleen of normal and immunized mice has suggested that immunity is dependent upon development of a secondary immunological response which arises approximately 7 days after introduction of the challenge infection. Although humoral antibody production forms part of this secondary response, it is not necessarily responsible for control of the infection.
Spontaneous and Induced Mutation in
Mycobacterium avium
Authors: McCarthy Charlotte
Published: January 2020

Mycobacterium avium
exhibits two colonial forms, transparent and opaque, on 7H10 agar. The transparent variant of
M. avium
B2900 undergoes a spontaneous transition to the opaque form at the rate of 4.7 × 10
−5
to 3.5 × 10
−4
per cell per generation. The two variants differ in cell morphology and mass; the opaque cells are two to three times as large as the transparent in terms of dry weight, total protein, deoxyribonucleic acid, or carbohydrate. A search for auxotrophic mutants resulted in the induction, by nitrosoguanidine or ultraviolet irradiation, of conditional, salt-sensitive mutants. One such mutant requires methionine and tryptophan supplementation for growth in a medium containing a buffer at high molarity. The clinical and physiological significance of these findings is discussed.
Role of Cell Wall Structure of
Salmonella
in the Interaction with Phagocytes
Authors: Friedberg D. , Shilo M.
Published: January 2020

Wild-type and cell wall mutants of
Salmonella
were examined for sensitivity to ingestion and intracellular killing in vitro by mouse peritoneal macrophages and guinea pig polymorphonuclear leukocytes. A complete polysaccharide core of the cell wall is important for resisting ingestion and intracellular killing, and the presence of the O-specific side chains contributes further resistance. Uridine diphosphate-gal-4-epimeraseless mutants grown on galactose-supplemented medium, rendering them smooth phenotypes, showed resistance to ingestion and intracellular killing similar to the wild type.
Experimental Transplacental Transmission of St. Louis Encephalitis Virus in Mice
Authors: Andersen A. A. , Hanson R. P.
Published: January 2020

Transplacental infection of the mouse embryo with St. Louis encephalitis (SLE) virus was produced by injecting the mother with virus at various stages of gestation. Intravenous or subcutaneous injection of the mother with 10
5.9
suckling mouse median lethal dose (SMLD
50
) of SLE virus was found to infect 83 to 96% of the embryos when given at 4 days of gestation or later. Injections at 6 days of gestation or earlier had little effect on the embryo although virus could be recovered at 10 days of gestation when injected at 4 days of gestation, whereas injections at 7 days or later resulted in a high mortality at birth and during the first week of life. Embryos from females injected at 7 to 9 days of gestation were found to have become infected when necropsied 3 days after injection, but no virus could be isolated from the young of similarly infected mothers at birth. A large number of these young died at birth, and some were observed with signs of anoxia and incoordination. Young of mothers injected later in pregnancy usually lived for a few hours to a few days and were then observed to die with signs of encephalitis. Virus was routinely isolated from these mice.
Polysaccharides of
Mycobacterium bovis
Ushi 10,
Mycobacterium smegmatis, Mycobacterium phlei
, and Atypical
Mycobacterium
P1
Authors: Azuma Ichiro , Ajisaka Mutsuya , Yamamura Yuichi
Published: January 2020

Four kinds of polysaccharides, glucan, mannan, arabinomannan, and arabinogalactan, were purified from the defatted cells of four strains of mycobacteria. By the chemical and immunological analyses, we concluded that arabinomannan and arabinogalactan are common serologically active polysaccharides in mycobacteria.
Fluorescent-Antibody Marker for Vaccine-Induced Rubella Antibodies
Authors: Brown Gordon C. , O'Leary Theresa P.
Published: January 2020

Tests with LLC-MK2 and BHK-21 cells showed that the fluorescent-antibody (FA) procedure can be used to differentiate antibodies resulting from natural infection and antibodies stimulated by rubella vaccine virus. Negative or weak FA reactions in LLC-MK2 cells and strong reactions in BHK-21 cells indicated antibody stimulated by the vaccine virus; strong reactions in both cell systems reflected naturally acquired immunity.
Orofacial Herpes Simplex Virus Infection in Hairless Mice: Latent Virus in Trigeminal Ganglia After Topical Antiviral Treatment
Authors: Klein Richard J. , Friedman-Kien Alvin E. , Yellin Paul B.
Published: January 2020

Inoculation of herpes simplex virus on the forehead and/or snout of hairless mice resulted in a significantly lower mortality rate than inoculation of the skin in the lumbosacral area. Latent herpes simplex virus infections were detected in all forehead-inoculated and in 90% of snout-inoculated mice. Phosphonoacetic acid was highly effective in preventing the development of skin lesions, and no latent infections were detected when phosphonoacetic acid ointment was applied 3 h after infection. Neither adenine arabinoside nor adenine arabinoside monophosphate prevented the establishment of latent infections in the trigeminal ganglia, although they protected the mice from the fatal outcome of the infection. The antibody response after adenine arabinoside or adenine arabinoside monophosphate treatment was similar to that observed in untreated animals, and it was six to eight times higher than in mice treated with phosphonoacetic acid. Mice without evidence of latent infection had, in general, lower serum antibody titers than those with latent infections in the ganglia. An analysis of the pathogenesis of herpes simplex virus infection in mice treated with adenine arabinoside showed that virus penetration into the nerve endings was delayed and that the amount of free virus in ganglionic homogenates was 10 to 100 times less than that for untreated mice.
In vitro and in vivo photosensitized inactivation of dermatophyte fungi by heterotricyclic dyes
Authors: Propst C , Lubin L
Published: January 2020

The ability of three heterotricyclic dyes to photosensitize dermatophyte fungi was studied with Trichophyton mentagrophytes and Microsporum gypseum. In vitro studies showed that methylene blue, neutral red, and proflavine were capable of killing these fungi when used in conjunction with broad-spectrum light. Proflavine, however, killed both fungi most rapidly and was used for further studies. Fungal killing by proflavine plus light was dependent on dye concentration, pH, light wavelength, and light intensity. Based on the in vitro studies, a treatment regimen was developed for in vivo use on experimentally infected animals. When treatment of guinea pigs inoculated with T. mentagrophytes was begun during fungal invasion, lesion formation at inoculated sites was either prevented or substantially reduced. When treatment was begun after lesion formation, however, light-plus-dyed treated sites showed only slightly faster curing than untreated sites.
Effect of minerals on staphylococcal enterotoxin B production
Authors: Keller G M , Hanson R S , Bergdoll M S
Published: January 2020

Raising the magnesium level from 0.4 to 1.5 mM in a medium containing only amino acids (2.08%), salts, and vitamins increased enterotoxin B production by Staphylococcus aureus S-6 by about 80%. The level of phosphates in the medium was lowered to one-tenth (to 2.87 mM) the original amount without adversely affecting growth and enterotoxin production. The optimum level of potassium was between 15 and 45 mM. Ammonium salts were not essential in the amino acid medium. Sufficient quantities of trace metals were already present. Revising the salt mixture according to the information obtained resulted in a doubling of the enterotoxin B production.
Immunogenic capacity of ribosomes of Salmonella typhi interfered with a flagellin-like material contaminant
Authors: Cofré G , Calderón I , Mora G C
Published: January 2020

The double-immunodiffusion technique and sodium dodecyl sulfate-polyacrylamide electrophoresis were used to demonstrate the presence of flagellin-like material strongly attached to ribosomes of Salmonella typhi Ty 2. This flagellin-like material contaminating the ribosome preparation interferes with the induction of antiribosome serum promoting the formation of antisera reacting either only with flagellin or in some cases with flagellin and ribosomes, but giving a very weak reaction with the latter. The interference is also observed when purified ribosomes from a nonflagellated mutant of S. typhi (S. typhi O-901) mixed with purified S. typhi Ty 2 flagellin are utilized as antigens. The antiribosome sera obtained with ribosomes from S. typhi O-901 have a considerably higher titer than those that are interfered with. These sera were able to react with ribosomes obtained from several related species and did not react with flagella-derived flagellin of S. typhi Ty 2.
Direct syncytial assay for the quantitation of bovine leukemia virus
Authors: Benton C V , Soria A E , Gilden R V
Published: January 2020

A direct in vitro tissue culture method is described for the quantitation of bovine leukemia virus, utlizing a feline S+L-- cell line.
In vitro establishment of Marek's disease herpesvirus-transformed productive and nonproductive lymphoblastoid cell lines
Authors: Munch D , Hohlstein L , Sevoian M
Published: January 2020

The establishment of two Marek's disease herpesvirus-transformed lymphoblastoid cell lines (JMV-1 and JM-1) is reported. Cocultivation with chicken embryo fibroblasts, attempts to rescue Marek's disease virus from kidney cell cultures, and immunofluorescent staining show that JMV-1 is a nonproductive line and JM-1 is a productive line.
Increased Bone Marrow Production of Granulocytes and Mononuclear Phagocytes Induced by Mycobacterial Adjuvants: Improved Recovery of Leukopoiesis in Mice After Cyclophosphamide Treatment
Authors: Buhles William C. , Shifrine Moshe
Published: January 2020

The effects of complete Freund adjuvant (CFA) or
Mycobacterium bovis
BCG on leukopoiesis and on leukopoietic recovery from cyclophosphamide treatment in mice was studied. CFA injected subcutaneously or intraperitoneally resulted in increased blood granulocyte and monocyte counts, increased numbers of bone marrow granulocyte and mononuclear phagocyte progenitors, and increased hematopoietic colony-stimulating factor in the serum. Furthermore, the quantitative cellular response within 24 h to an induced sterile intraperitoneal inflammation (thioglycolate) was augmented by subcutaneous CFA. In mice given CFA subcutaneously, blood granulocyte counts, as well as the peritoneal granulocyte and macrophage response to intraperitoneal thioglycolate, recovered more quickly than did those of the controls after a 250-mg/kg dose of cyclophosphamide. CFA-treated mice consistently maintained blood granulocyte and monocyte counts 1.3-to 4-fold higher than those of the controls for 2 weeks while receiving 75 mg of cyclophosphamide per kg every other day. Mice pretreated with CFA intraperitoneally had higher numbers of bone marrow colony-forming units in culture and higher levels of serum colony-stimulating factor after 250-mg/kg injections of cyclophosphamide. Similarly, BCG resulted in increased bone marrow colony-forming units in culture, increased serum colony-stimulating factor, and a faster return of the peritoneal inflammatory response after cyclophosphamide injection. These results show that mycobacterial adjuvants accelerate recovery of leukopoietic functions after cyclophosphamide treatment and suggest a mechanism whereby such adjuvants afford nonspecific protection against infection in immunosuppressed mice.
Innate resistance of mice to experimental infection with Naegleria fowleri
Authors: Haggerty R M , John D T
Published: January 2020

The mouse system provides an excellent model for studying host resistance to Naegleria fowleri, the agent of primary amoebic meningoencephalitis. Innate resistance to infection with N. fowleri was examined with respect to infecting dose and the age, sex, and strain of mice. Intravenous inoculation with 10(7) amoebae per mouse produced 100% mortality in 9 days, whereas inoculation with fewer amoebae reduced the cumulative mortality. Male and female DUB/ICR mice of varying ages were inoculated intravenously with 2.5 X 10(5) N. fowleri per g of body weight. The youngest mice died first, with 100% mortality for both males and females, and mortality decreased with increasing age. Female mice were significantly more resistant to infection than males. Five strains of mice weighing approximately 20 g were inoculated intravenously with weight-adjusted doses; mortality ranged from 10% in C57BL/6 mice to 95% in A/HeCr mice.
Ideal target organism for quantitative bactericidal assays
Authors: Hooke A M , Oeschger M P , Zeligs B J , Bellanti J A
Published: January 2020

We have developed a target organism which permits quantitative bactericidal assays. The organism is an Escherichia coli mutant which cannot grow at the temperature of the assay (37 degrees C), but retains full colony-forming potential for subsequent quantitation at 25 degrees C. We show that quantitative data on the bactericidal capacity of polymorphonuclear leukocytes and alveolar macrophages can be obtained when this mutant is used as a target. The procedure used to generate the strain is described in detail and should be applicable to many bacterial species. Characterization of the properties of the mutant indicates that it has a strong potential for use in other in vivo and in vitro investigations of host responses to microbial invasion.
Cultures of
Chlamydia trachomatis
in Mouse Peritoneal Macrophages: Factors Affecting Organism Growth
Authors: Kuo Cho-Chou
Published: January 2020

Growth of
Chlamydia trachomatis
B/TW-5/OT and L
2
/434/Bu strains in cultures of thioglycolate-activated mouse peritoneal macrophages was studied. Both strains grew to a limited extent in the macrophages, but lymphogranuloma venereum (LGV) grew better than trachoma. Growth was enhanced by centrifugation of the inoculum onto the macrophage cell layer and inhibited by pretreatment of macrophages for 2 h with 100 μg of concanavalin A per ml. No significant effect was observed by pretreatment of macrophages with diethylaminoethyl-dextran (30 μg/ml, 30 min), cytochalasin B (20 μg/ml, 1 h), and cyclophosphamide (200 μg/ml, overnight) or by treatment with hydrocortisone (1 and 10 μg/ml, overnight before inoculation and during a 2-day incubation after inoculation). Resistance to intracellular growth of the two organisms was not increased in macrophages obtained from mice immunized with the organisms compared with macrophages from nonimmunized mice unless they were pretreated in vitro with penicillin (100 U/ml, overnight). The yields of LGV organisms from the penicillin-pretreated macrophages of LGV-immunized mice were 100-fold less than from the pretreated macrophages of nonimmunized control mice. At the same time, the yields of LGV organisms from penicillin-pretreated macrophages of mice immunized with trachoma, gonococcus, and HeLa cells were not different from those obtained in pretreated macrophages of nonimmunized control mice.
Delayed-type hypersensitivity in mice immunized with Trypanosoma rhodesiense antigens
Authors: Finerty J F , Krehl E P , McKelvin R L
Published: January 2020

When mice were immunized intravenously, subcutaneously, or by the footpad route with formaldehyde-killed Trypanosoma rhodesiense, delayed-type hypersensitivity was elicited by the use of frozen-thawed trypanosomal antigen. The delayed footpad swelling technique was used to measure delayed hypersensitivity. Hypersensitivity induction was dose dependent (greater than or equal to 10(6) formaldehyde-treated T. rhodesiense) and was affected by the route of immunization. The footpad route induced higher levels of hypersensitivity than other routes of immunization. Mice immunized with a single dose of formaldehyde-treated antigen and challenged with live T. rhodesiense did not survive. Yet, mice immunized subcutaneously with formaldehyde-treated antigen and then injected with frozen-thawed antigen and challenged 28 days after immunization survived. The results suggest that T-cell activation, manifested by delayed hypersensitivity responses, was a necessary component in the protective response, perhaps functioning in a helper cell capacity.
Suramin effects on macrophage phagolysosome formation and antimicrobial activity
Authors: Pesanti E L
Published: January 2020

The effects of suramin on phagolysosome formation and antimicrobial activity of mouse peritoneal macrophages cultivated in vitro have been studied. Prolonged in vitro pretreatment of macrophages with high concentrations of suramin caused macrophages to form large fragile phagolysosomes in which the concentrations of the various lysosomal enzymes were inferred to be diminished. In addition, suramin-treated macrophages demonstrated enhanced exocytosis of acid phosphatase during phagocytosis of polyvinyl toluene spherules. However, suramin was found not to inhibit formation of phagolysosomes in macrophages that had ingested Listeria monocytogenes when those cells were examined by the electron microscope. Suramin pretreatment did not alter the ingestion or intracellular killing of Staphylococcus aureus or of a strain of L. monocytogenes that was essentially avirulent for mice, but did protect macrophages from destruction by virulent L. monocytogenes ingested in vitro, an effect that appeared to have been mediated through enhancement of the bacteriostatic potential of the macrophages. However, at a single dosage level, the drug did not alter the mortality of mice challenged with virulent L. monocytogenes.
Relationship between delayed-type hypersensitivity and the progression of Mycobacterium lepraemurium infection
Authors: Poulter L W , Lefford M J
Published: January 2020

The relationship between the level of delayed-type hypersensitivity (DTH) and the progression of Mycobacterium lepraemurium infection was examined after inoculation of mice with 10(8) M. lepraemurium in the left hind footpad. The expression of DTH developed over the first 4 weeks of infection, remained high up to week 8, and then dropped to a low level at which it remained for 12 more weeks. The development of DTH was concordant with an initial swelling of the inoculated foot, the appearance of a mononuclear infiltrate at this site, and a prevention of any increase in the number of mycobacteria in this foot and in other tissues studied. A decay of DTH reactivity was associated with a progressive increase in the number of M. lepraemurium initially at the original site of inoculation and subsequently in all other tissues. Although the expression of DTH was lost, adoptive immunization experiments showed that a population of sensitized lymphocytes persisted within host. Further experimentation offered evidence to suggest that the level of systemic antigen may be in part responsible for the loss of DTH reactivity.
Properties of an Escherichia coli cytotoxin
Authors: Konowalchuk J , Dickie N , Stavric S , Speirs J I
Published: January 2020

Isoelectric focusing of a heat-labile cytotoxin of Escherichia coli H30 revealed the presence of two molecular variants, pI 7.2 and a comparatively small quantity of pI 6.8. Predominant component pI 7.2 had a molecular weight of 28,000, induced some fluid accumulation in rabbit ileal loops, and showed no morphological response in Y-1 cells but a strong cytotoxic effect on Vero cells.
Determination of virus-specific antigens in extracts from herpes simplex virus-infected cells by a Cr release inhibition test
Authors: Kutinová L , Vonka V
Published: January 2020

A 51cr release inhibition test (CRIT) was developed for determining herpes simplex virus type 1 antigens in infected cell extracts. Among the factors studied were the optimal concentrations of complement, antibody, and infected target cells. Under standardized conditions, the relationship between antigen content and inhibition of chromium release was linear in a semilogarithmic plot, indicating that the antigen content can be determined from testing two dilutions of a given preparation. Other tests showed that infected cells cryopreserved at -70 degrees C for periods exceeding 3 months can be used in CRIT. Five different batches of infected cell extracts were tested in both CRIT and blocking neutralization tests with comparable results being obtained, suggesting that both tests measure the same activity.
Enhancement of lymphocyte blastogenic and delayed hypersensitivity skin responses by indomethacin
Authors: Muscoplat C C , Rakich P M , Thoen C O , Johnson D W
Published: January 2020

Incubation of Mycobacterium bovis-sensitized bovine peripheral blood lymphocytes with concanavalin A or M. bovis purified protein derivative and indomethacin caused a consistent, statistically significant increase in [3H] thymidine uptake as compared to cultures without indomethacin. The kinetics of the response showed that indomethacin must be added to lymphocyte cultures within hours after mitogen or antigen addition for enhancement of [3H]thymidine uptake to occur. Lymphocyte blastogenic responses to purified protein derivative were enhanced in both normal and M. bovis-sensitized lymphocyte cultures. However, enhancement of sensitized lymphocyte responses was significantly (P less than 0.01) greater than that in normal animals. Additionally, indomethacin treatment of M. bovis-sensitized guinea pigs singnificantly augmented delayed skin reactions to tuberculin. Delayed hypersensitive skin reactions were only enhanced when indomethacin was administered simultaneously with tuberculin.