bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibition of Respiratory Virus Infections of Mice with Aerosols of Synthetic Double-Stranded Ribonucleic Acid
Authors: Gerone Peter J. , Hill David A. , Appell Loren H. , Baron Samuel
Published: January 2020

Aerosols of double-stranded complexes of polyinosinic and polycytidylic acids (poly I:C) were useful in protecting mice infected with aerosols of influenza (A
2
/Taiwan/64) and parainfluenza type 1 (Sendai) viruses. Administration of poly I:C as an aerosol offers an advantage, particularly in therapy, by eliminating the risk of pulmonary dissemination of viral infections due to intranasally instilled fluids. Treatment of mice with aerosols of poly I:C reduced the infection rate with influenza virus but did not inhibit virus multiplication in the lungs of most of those animals where infection became established. Sendai virus infection rates were undiminished in mice treated with poly I:C, but lung-virus titers were significantly suppressed as compared with those of untreated animals. The maximum poly I:C doses (40 μg) administered by aerosol produced no evidence of toxicity in the mice.
Ultrastructural Analysis of the Effects of Penicillin and Chlortetracycline on the Development of a Genital Tract
Chlamydia
Authors: Kramer M. J. , Gordon Francis B.
Published: January 2020

The developmental cycle of a genital tract
Chlamydia
(MRC-1/G) growing in irradiated monkey kidney cell monolayers was analyzed by electron microscopy. Growth was essentially similar to that of
C. psittaci
and ocular isolates of
C. trachomatis.
Penicillin (50 units/ml) interfered with the growth cycle by producing greatly enlarged initial bodies which sometimes measured 3 μm instead of the normal 1 to 1.3 μm in diameter. In contrast to penicillin, chlortetracycline (10 μg/ml) did not grossly distort morphology of the initial body but had a definite inhibitory effect on the formation of elementary bodies depending upon the time postinfection the antibiotic was added. If added 24 hr or later postinfection, typical inclusions containing elementary bodies were formed. When administered 18 hr postinfection, the transition of initial bodies to elementary bodies was prevented, and the inclusion was much smaller when examined at 48 hr in comparison to a control without chlortetracycline. Addition of the drug at 6 or 12 hr postinfection resulted in very small inclusions which contained only one or two chlamydiae of an initial body type. It was not possible to detect chlamydiae when chlortetracycline was added immediately after adsorption (0 hr), and cells were examined by light and electron microscopy at 48 hr.
Comparison of the Effects of a Synthetic Polyribonucleotide with the Effects of Endotoxin on Selected Host Responses
Authors: Berry L. Joe , Smythe Dorothy S. , Colwell Louise S. , Schoengold Ronald J. , Actor Paul
Published: January 2020

An injection of a small dose (1 to 50 μg) of synthetic polyriboinosinic acid complexed with polyribocytidylic acid (poly I:poly C) inhibited the induction of tryptophan oxygenase by cortisone acetate; it induced tyrosine amino transferase, and it accelerated the loss of liver glycogen reserves. It also resulted in first a suppression followed by an activation of the reticuloendothelial system as judged by the rates of carbon clearance from blood. All of these responses are elicited by comparable doses of endotoxin. Pretreatment of mice with poly I:poly C did not, or only marginally, increased their nonspecific resistance to infection with several bacterial pathogens, and it failed to result in the development of tolerance to endotoxin, effects known to be produced by endotoxin when given under similar conditions.
Enhancement of Bacterial Infections in Mice by Newcastle Disease Virus
Authors: Hugh Rudolph , Huang Kun-Yen , Elliott Thomas B.
Published: January 2020

This report describes an attempt to define the factors which incite secondary bacterial pneumonias. Groups of mice were given bacteria intraperitoneally and, at various intervals, Newcastle disease virus intravenously. There was an increase in the number of deaths and in the rates of death in these groups, when compared with a control group which was given only bacteria. These results were obtained with
Streptococcus pneumoniae
(
Diplococcus pneumoniae
),
Pseudomonas aeruginosa
, and
Salmonella enteritidis
ser.
typhimurium.
Newcastle disease virus increased the mortality rate of mice with bacterial infections when the two agents were given within 24 hr.
Evidence for Molecular Heterogeneity of the Specific Antigen (Fraction-1) of
Pasteurella pestis
Authors: Habig William , Hudson Bruce W. , Marshall John D. , Cavanaugh Dan C. , Rust James H.
Published: January 2020

Fraction-I (F-I) protein, the specific antigen of
Pasteurella pestis
, appears to be a series of molecular aggregates of identical subunits, all of which have serological reactivity with specific F-I antiserum.
Effects of Panton-Valentine Leukocidin of
Staphylococcus aureus
on Leukocytes from Patients with Leukemia
Authors: Blobel H. , Wenk K. , Kanoe M.
Published: January 2020

Mature granulocytes from six patients with myelocytic leukemia and monocytic cells from two patients with monocytic leukemia were damaged after incubation with leukocidin from
Staphylococcus aureus
. The immature granulocytes were not significantly affected. The lymphocytic cells from one patient with lymphocytic leukemia were not markedly damaged. The numbers of erythrocytes from all nine patients remained practically unchanged with lower concentrations of leukocidin.
Effect of Separate and Combined Injections of Poly rI: Poly rC and Endotoxin on Reticulo-endothelial Activity, Interferon, and Antibody Production in the Mouse
Authors: Chester Thomas J. , de Clercq Erik , Merigan Thomas C.
Published: January 2020

The effect of repeated stimulation on both the interferon and antibody systems and on reticuloendothelial activity was studied by injection of endotoxin 2 days before injection of (poly rI):(poly rC). A single injection of endotoxin or (poly rI):(poly rC) increased or decreased the response in each system depending on the time of administration. If the injection of (poly rI):(poly rC) was preceded by an injection of endotoxin 2 days before, its activity was markedly reduced in all of the three systems studied. Although different doses of endotoxin were required to induce a state of hyporeactivity or tolerance to the effects of (poly rI):(poly rC) in either system, it is possible that a common mechanism underlies the hyporeactivity in all systems.
Selective Bacterial Adherence to Oral Epithelial Surfaces and Its Role as an Ecological Determinant
Authors: Gibbons R. J. , van Houte J.
Published: January 2020

The possible relationship between the ability of
Streptococcus
species to adhere to oral epithelial cells and their natural distribution on epithelial surfaces within the mouth was studied. Strains of
S. salivarius
and
S. sanguis
, which are present in significant proportions on oral epithelial surfaces, were found to possess a definite capacity to adhere to epithelial cells obtained from cheek scrapings of humans, hamsters, and germ-free rats. In contrast, strains of
S. mutans
, which are found in only minor proportions, if at all, on oral epithelial surfaces exhibited feeble or no adherence to oral epithelial cells.
S. salivarius
cells attached well to human cheek cells over the range of
p
H 5 to 8. Its adherence was not found to be markedly influenced by saliva or by growth in sucrose broth. Several other types of bacteria were examined which also exhibited widely different abilities to attach to human cheek cells. Mixtures of streptomycin-labeled strains were introduced into the mouths of volunteers for study of the adherence of
Streptococcus
species to oral epithelial surfaces in vivo. Labeled
S. salivarius
and
S. sanguis
were recovered in high proportions from cheek and tongue surfaces, whereas the proportions of labeled
S. mutans
recovered from these surfaces were low in comparison to the original mixture. These data indicate that a correlation exists between the relative adherence of various
Streptococcus
species and their proportional distribution found naturally on oral epithelial surfaces. The ability of bacteria to adhere to surfaces is proposed as a critical ecological determinant affecting their colonization in environments with open surfaces exposed to bathing fluids.
Extracellular Antigens from
Listeria monocytogenes
I. Purification and Resolution of Hemolytic and Lipolytic Antigens from Culture Filtrates of
Listeria monocytogenes
Authors: Jenkins E. M. , Watson B. B.
Published: January 2020

Two antigens were purified from culture filtrates of
Listeria monocytogenes
7973 by the following procedure: (i) acid precipitation with 4
n
HCl at
p
H 3.7, (ii) Sephadex G-75 column fractionation, (iii) diethylaminoethyl-Sephadex A50 batchwise adsorption, and (iv) rechromatography on Sephadex G-75. This procedure resulted in the resolution of two distinct antigens. One antigen, designated a hemolytic antigen because of its ability to lyse erythrocytes from a variety of species, had a specific activity of 25,000 units/mg of protein and an estimated molecular weight of at least 171,000. The other antigen, designated a lipolytic antigen because of its ability to hydrolyze egg yolk saline substrate, had a specific activity of 400 units/mg of protein and an estimated molecular weight of 52,500.
Role of the Phagocyte in Host-Parasite Interactions XXVII. Myeloperoxidase-H
2
O
2
-Cl
−
-Mediated Aldehyde Formation and Its Relationship to Antimicrobial Activity
Authors: Strauss R. R. , Paul B. B. , Jacobs A. A. , Sbarra A. J.
Published: January 2020

Evidence is presented which suggests that the mechanism of action of the myeloperoxidase-H
2
O
2
-Cl
−
antimicrobial system in the phagocyte is by the formation of aldehydes. Aldehyde production resulting from myeloperoxidase-mediated decarboxylation and deamination of alanine was quantitated with 20,000-g granules from guinea pig polymorphonuclear leukocytes serving as the enzyme. Equimolar quantities of acetaldehyde and CO
2
were obtained. There was an absolute requirement for both H
2
O
2
and Cl
−
for decarboxylation by the myeloperoxidase-containing granules. The myeloperoxidase-H
2
O
2
-Cl
−
system decarboxylated both
d
- or
l
-alanine equally and had a
p
H optimum of 5.3. Decarboxylation of
l
-alanine by intact guinea pig polymorphonuclear leukocytes was increased 2.5-fold by phagocytosis. Guaiacol peroxidation by the granules was inhibited 90% in the presence of Cl
−
at acid
p
H. Under these conditions, decarboxylation and deamination of amino acids by myeloperoxidase were significantly stimulated, resulting in aldehyde production. Taurine, a competitive inhibitor of amino acid decarboxylation, inhibited bactericidal activity of the myeloperoxidase-H
2
O
2
-Cl
−
system but had no effect on the myeloperoxidase-H
2
O
2
-I
−
bactericidal system. Since the myeloperoxidase-H
2
O
2
-I
−
system does not participate in amino acid decarboxylation, its mechanism of antimicrobial action appears to be different from that found with Cl
−
.
Transmissible Disease, Probably Viral in Origin, Affecting the Amebocytes of the European Shore Crab,
Carcinus maenas
Authors: Bang Frederik B.
Published: January 2020

A transmissible infection of the shore crab (“crabe enragée”),
Carcinus maenas
, was discovered in one of about 700 of this species collected by the Station Biologique, Roscoff, France. The infection has been transferred by subinoculation through four serial passages in crabs collected at Roscoff and through six more passages in
C. maenas
collected at Woods Hole, Mass. The agent causes abnormal cellular clotting, a drop in the peripheral amebocyte count, clumping of amebocytes in the peripheral tissue and blood, and abnormal behavior of the amebocytes of the infected animal on glass. Mortality over a period of some weeks is negligible. Electron microscopy shows characteristic virus particles, about 55 to 125 nm in size, in the infected amebocytes. The agent is present in large amounts in the whole blood and serum, is filterable, heat labile, and has been preserved in the frozen state. Final identification will depend upon purification, growth in tissue culture, and further electron microscopy.
Particulate Fractions of
Neisseria gonorrhoeae
Authors: Kellogg Douglas S. , Turner Emily M. , Callaway Carey , Lee Linda , Martin John E.
Published: January 2020

Passage of gonococcal cells through a Ribi cell fractionator produced a mixture of protoplasm and cell particulates, the latter being separable in sucrose solutions. Separation of these particulates resulted in the detection of objects identified as cell walls and “plasts.” The latter objects had an average diameter of 1.00 ± 0.05 μm and consisted of spatially oriented granules surrounded by a membrane-like structure only. Cell wall structures were not observed with these plasts. Plasts were morphologically stable in distilled water and at low
p
H values. Although 50% more pressure was required to rupture plasts than whole cells, plast morphology was destroyed by organic solvents. Whole cell and plast morphology was examined by electron and phase microscopy, and certain correlations were made between structure and morphological stability. Cell wall antiserum reactivities were quantitatively different for plasts and cell walls. Serological reactivities of plasts were separable by sonic oscillation and differential centrifugation of the sonically treated material.
Separation of Gamma Hemolysin from
Staphylococcus aureus
Smith 5R
Authors: Möllby R. , Wadström T.
Published: January 2020

Staphylococcus aureus
strain Smith 5R was found to produce a hemolysin with an isoelectric point of 9.5 and with a hemolytic spectrum different from alpha, beta, and delta hemolysins.
Metabolism of Common Substrates by the Reiter Strain of
Treponema pallidum
Authors: Allen S. L. , Johnson R. C. , Peterson D.
Published: January 2020

The utilization of glucose, amino acids, fatty acids, bicarbonate, purines, and pyrimidines by the Reiter treponeme was studied by using carbon 14-labeled substrates. The distribution of carbon from the substrates into various cell components was determined. Radioactivity from labeled bicarbonate in the cellular protein was restricted to aspartic acid. The Reiter treponeme is capable of synthesizing glycine, serine, alanine, aspartic acid, glutamic acid, proline, and possibly ornithine. Phenylalanine, arginine, lysine, leucine, isoleucine, valine, threonine, and histidine do not appear to be synthesized by this treponeme. The Reiter treponeme cannot synthesize fatty acids, and thymine is not incorporated. Glucose is a major carbon and energy source. Arginine, histidine, serine, threonine, and glutamic acid are degraded by the Reiter treponeme and may serve as energy sources. It was calculated that exogenously supplied amino acids contribute 41 to 54% of the cellular material; fatty acids, 18%; and glucose, 28 to 43%.
Escherichia coli
Isolated from Domestic Animals Pathogenic for Gnotobiotic Piglets
Authors: Meyer R. C. , Rhoades H. E. , Saxena S. P. , Simon J.
Published: January 2020

Three strains of
Escherichia coli
isolated from infectious processes in a calf, a dog, and a cat were examined for their capacity to produce disease or death, or both, in newborn gnotobiotic piglets. The O groups represented by these particular strains of
E. coli
were O4: (canine origin), O6: (feline origin), and O39: (bovine origin). All three isolates upon oral administration proved to be pathogenic. Infection with the
E. coli
O4: (canine) or O39: (bovine) consistently produced signs of enteric coli-bacillosis and death in all 1- and 3-day-old piglets within 24 to 48 hr. The O6: (feline) isolate, on the other hand, produced a marked polyserositis and generally required 6 to 7 days to kill a piglet. Only the respective type of
E. coli
used in the particular trial was recovered from the diseased piglets. These findings suggest the possible role of domestic animals and household pets in the spread of potentially pathogenic
E. coli
to other species.
Immunochemical Studies of Two Cholera Toxin-Containing Standard Culture Filtrate Preparations of
Vibrio cholerae
Authors: Holmgren J. , Lönnroth I. , Ouchterlony Ö.
Published: January 2020

Two crude toxin preparations of
Vibrio cholerae
, labeled lot 4493 G (Inaba) and lot 001 (Ogawa), consisting of freeze-dried culture filtrate, were studied with regard to toxicity, precipitinogenicity, and chemical composition. Lot 4493 G contained much more carbohydrate and less protein than lot 001, but both of the preparations contained three precipitinogens which were identical. One of these factors was identified as cholera exotoxin. In addition, both contained a fourth cross-reacting precipitinogen related to lipopolysaccharide. The toxicity of the lots was very similar. The toxin active as permeability factor in the intradermal test, identified completely in comparative double-diffusion analyses with the toxin causing cholera-like symptoms in experimental animals, strongly indicated that the same toxin molecule was active in the two different model systems. The isoelectric point of the toxin was about
p
H 7, but some toxic activity focused toward a
p
H of 9. The toxicity was completely retained by a UM-10 membrane (cut at a molecular weight of 10,000), practically retained by a PSED membrane (cut at a molecular weight of 25,000), but not retained by an XM-50 membrane (cut at a molecular weight of 50,000). By gel filtration through agarose, it was possible to separate and purify more than 1,000-fold the toxin from the other, more rapidly filtering three precipitinogens. With lot 4493 G, the toxicity of the agarose gel filtration fractions was restricted to an elution volume similar to that of globular proteins with a molecular weight of 25,000 to 38,000, whereas gel filtration experiments through Sephadex G-75 indicated a size of the toxin corresponding to a molecular weight of about 55,000 to 60,000.
Stimulation of Enterotoxin B Production I. Stimulation by Fractions from a Pancreatic Digest of Casein
Authors: Wu Cheng-Hsien , Bergdoll Merlin S.
Published: January 2020

Chromatography on Dowex 50-X2 of Protein Hydrolysate Powder (Mead Johnson International, Evansville, Ind.), a pancreatic digest of casein, yielded 18 fractions. Five fractions stimulated enterotoxin production in greater amounts than were produced in the basal medium when it contained Protein Hydrolysate Powder. The stimulatory effect was due to the presence of peptides in the fractions. Many of these peptides contained large amounts of proline. Apparently, the primary structure of the peptides was important in the stimulation effect.
Stimulation of Enterotoxin B Production II. Synthetic Medium for Staphylococcal Growth and Enterotoxin B Production
Authors: Wu Cheng-Hsien , Bergdoll Merlin S.
Published: January 2020

A relatively large amount of enterotoxin B (125 μg/ml) was produced in a synthetic medium composed of amino acids, inorganic salts, and vitamins. This medium was prepared on the basis of the utilization of the various amino acids by
Staphylococcus aureus
strain S-6 throughout the growth cycle. Arginine appeared to be essential for enterotoxin production. The pattern of enterotoxin production in the synthetic media appeared to differ from that in complex media.
Pathogenesis of Feline Panleukopenia Virus in Susceptible Newborn Kittens I. Clinical Signs, Hematology, Serology, and Virology
Authors: Csiza C. K. , Scott F. W. , De Lahunta A. , Gillespie J. H.
Published: January 2020

Inoculation of susceptible newborn kittens with a large dose of panleukopenia virus caused subclinical infection in 19 of 23 cases. All infected kittens developed severe and prolonged leukopenia. Cell-free virus was present in the blood from 1 to 7 postinoculation days. The virus spread to all organs, regardless of the route of inoculation. The thymus, spleen, mesenteric lymph nodes, and the cerebellum were the most severely infected organs. Kittens responded to virus infection by production of specific antibodies, first detectable in the circulatory system 6 to 8 days after infection. Antibody production preceded recovery from leukopenia by 3 days.
Stimulation of Leukocyte Hexose Monophosphate Shunt Activity by Ascorbic Acid
Authors: Cooper M. Robert , McCall Charles E. , DeChatelet Lawrence R.
Published: January 2020

Ascorbic acid in vitro markedly stimulates the hexose monophosphate shunt in normal human neutrophils, rabbit alveolar macrophages, and in neutrophils from a patient with chronic granulomatous disease.
Characterization of Shigella dysenteriae 1 (Shiga) toxin purified by anti-Shiga toxin affinity chromatography
Authors: O'Brien A D , LaVeck G D , Griffin D E , Thompson M R
Published: January 2020

Shigella dysenteriae 1 (Shiga) toxin was purified from whole-cell lysates by antitoxin affinity column chromatography, radioiodination, and Sephacryl S-200 gel filtration of 125I-labeled affinity column eluates. Two chromatographic peaks were observed. The percentage of radioactivity in peak I samples immunoprecipitated with antitoxin ranged from 95 to 100%. A pool of samples from this first peak contained over 90% of the HeLa-cell-cytotoxic units applied to the column and was enterotoxic for rabbit ileal loops and lethal for rabbits. This radiolabeled material migrated as a single cytotoxic band after nondenaturing polyacrylamide gel electrophoresis, but formed three bands, of 33,000, 29,000, and 4,000 to 7,000 daltons, after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In addition, material estimated as 7,000 daltons by Bio-Gel P-10 chromatography could be generated by treatment of S-200 peak I samples with 8 M urea. Pooled fractions from the second S-200 peak were separable into several low-molecular-weight peaks on a P-10 column. One of these P-10 peaks (7,000 daltons) was 27% immunoprecipitable with antitoxin. These data indicate that three of the known biological activities of Shiga toxin are associated with a 33,000-dalton substance which can be dissociated into 29,000- and 4,000- to 7,000-dalton components.
Separation of Sendai virus glycoproteins by using glutaraldehyde-treated erythrocytes and preparation of monospecific antisera against the glycoproteins
Authors: Hosaka Y
Published: January 2020

Sendai virus hemagglutinin-neuraminidase (HN) and fusion (F) glycoproteins, F and HN, were separated from Triton X-100- or Nonidet P-40-solubilized envelopes as unadsorbed and eluted fractions, respectively, by using glutaralde-hyde-treated chicken erythrocytes. These separated glycoproteins were biologically active. Monospecific antisera (in terms of monoreactivity to virus glycoproteins in gel diffusion precipitation patterns) were prepared by using these fractions as immunogens. Anti-HN rabbit serum inhibited all of the viral activities tested (infectivity, neuraminidase, hemagglutinating, and viral hemolysis), whereas anti-F serum definitely inhibited viral hemolysis only, although the two antisera enhanced neutralization in the presence of complement. The advantages and disadvantages of this separation method were discussed.
Epidemic typhus infection in cynomolgus monkeys (Macaca fascicularis)
Authors: Gonder J C , Kenyon R H , Pedersen C E
Published: January 2020

A nonhuman primate model of clinical Rickettsia prowazekii infections was developed in cynomolgus monkeys (Macaca fascicularis). Monkeys infected intravenously with 10(7) plaque-forming units developed clinical signs of illness and pathological changes characteristic of epidemic typhus infection in humans. Increases in total leukocyte counts, serum alkaline phosphatase, blood urea nitrogen, and serum glutamic pyruvate transaminase values were observed. Microscopic examination revealed typical typhus nodules in the brains of two monkeys that died. These data indicated that the cynomolgus monkey is a suitable model for study of the pathogenesis of epidemic typhus infection and may prove valuable in the evaluation of candidate R. prowazekii vaccines.
Secretory immunological response in infants and children to parainfluenza virus types 1 and 2
Authors: Yanagihara R , McIntosh K
Published: January 2020

The secretory immunological responses to natural infection with parainfluenza viruses ae not well defined. Nasopharyngeal secretion specimens from 20 infants and children naturally infected with parainfluenza virus type 1 or type 2 were examined for class-specific antibody and virus-neutralizing activity. There was a marked discordance in individual secretions between immunoglobulin A (IgA) antibody (as measured by indirect immunofluorescence) and neutralizing activity (as determined by either hemadsorption plaque or 50% tissue culture infective dose reduction) to the infecting parainfluenza virus type. Many secretions contained neutralizing activity in the absence of detectable IgA antibody; conversely, secretions with measureable IgA antibody frequently lacked neutralizing activity. Moreover, there was no relationship between neutralizing activity and the course of illness. All 11 patients with serial secretion specimens showed a fourfold or greater titer rise in IgA antibody to the homologous parainfluenza virus type. Antibody usually appeared 7 to 10 days after the onset of symptoms and peaked at about 2 weeks. This response did not appear to be related to age or to severity of illness. in general, the secretory responses resembled those seen in infants infected with respiratory syncytial virus.
Identification of a chromosomal determinant of alpha-toxin production in Staphylococcus aureus
Authors: Brown D R , Pattee P A
Published: January 2020

Production of alpha-toxin (the Hla+ phenotype, controlled by the Hla gene and scored as alpha-hemolytic activity) is a property of some isolates of Staphylococcus aureus NCTC 8325 and not of others. Genetic transformation between strains differing in the Hla phenotype revealed that the hla+ gene resides in the following sequence: purB110-bla+-hla+-ilv-129-pig-131; previously, the enterotoxin A (entA) gene of strain S-6 was shown to map very close to hla+. The hla+ mutations occurring naturally in strain Ps6 and after various mutagenic treatments in strains 8325 and 233 also mapped between bla+ and ilv-129. Among the isolates of strain 8325, the Hla+ phenotype was always associated with fibrinolytic activity, whereas Hla- isolates were non-fibrinolytic. This relationship was also observed among transformants selected for their Hla+ or Hla- phenotypes. The failure of Hla- strains and mutants to revert to hla+ at detectable frequencies, the instability of the Hla+ phenotype, and the previously observed pattern of recombination of the hla+ and entA+ determinants lend support to the view that hla+ may reside on a transposon; according to this view, Hla- mutants have lost the hla+-bearing transposon. It remains unclear whether hla+ is the structural gene for alpha-toxin.
Suppression of the intestinal immune response to cholera toxin by specific serum antibody
Authors: Pierce N F
Published: January 2020

The possibility that preexisting specific serum antibody could suppress a defined mucosal immune response to a topically applied antigen was studied in rats. Hyperimmune serum antibody induced by parenteral immunization of rats with cholera toxoid markedly suppressed the mucosal immune response to enterically applied cholera toxin. Such antibody was far more suppressive than antibody induced by primary parenteral immunization, apparently due to its greater avidity. Transfusion of small amounts (25 to 100 microliter) of hyperimmune serum suppressed the primary mucosal antitoxin response, the development of specific memory in the mucosal immune system, and, somewhat less effectively, the secondary mucosal antitoxin response. Suppression was due largely to a direct effect of serum antibody upon the interaction of absorbed enteric antigen with lymphoid tissue in Peyer's patches and, possible, mesenteric lymph nodes; interference with antigen absorption played little or no role in the observed suppression. These results do not explain the previously reported suppressive effect of primary parenteral immunization on the mucosal immune response to cholera toxin. However, they support the notions that repeated parenteral immunization can evoke avid serum antibody without necessarily stimulating mucosa-associated lymphoid tissue and that such antibody can markedly suppress primary and secondary phases of the local immune response to mucosally applied antigen. Thus, a mechanism is demonstrated by which repeated parenteral immunization may adversely affect efforts to initiate or sustain protective mucosal immune responses.
Cross-reactivity of Streptococcus mutans antigens and human heart tissue
Authors: Ferretti J J , Shea C , Humphrey M W
Published: January 2020

Rocket and two-dimensional immunoelectrophoreses were used to demonstrate that antisera from rabbits immunized with Streptococcus mutans strain B13 cross-reacted with human heart tissue. Absorption of the anti-S. mutans serum with S. mutans whole cells removed all reactivity to heart tissue, but did not remove the reactivity of an added antibody marker to its corresponding antigen. The anti-S. mutans serum reacted most intensely with heart tissue antigen and to a lesser degree with skeletal muscle, but not with liver or kidney tissues. These results support the conclusion that antigens of S. mutans cross-react with mammalian heart tissue and, further, suggest that caution should be exercised in the formulation of a dental caries vaccine containing S. mutans antigens.
Quantitation of antibody against cell wall mannan and a major cytoplasmic antigen of Candida in rabbits, mice, and humans
Authors: Jones J M
Published: January 2020

Cell wall mannan of type A Candida albicans was purified, conjugated with tyramine, and labeled with 125I. Labeled cell wall mannan was used in a radioimmunoassay to measure serum antimannan antibody levels. An ammonium sulfate-soluble fraction of a cytoplasmic extract of C. albicans contained a large amount of a major cytoplasmic antigen of this organism. When the sulfate-soluble fraction was labeled with 125I, much more 125I attached to this major antigen than to the other antigens present in the sulfate-soluble fraction. Thus, when serum antisulfate-soluble fraction antibody levels were measured by a radioimmunoassay which used the iodine-labeled sulfate-soluble fraction, antibody against this major cytoplasmic antigen was quantitated. Both radioimmunoassays were used to measure antimannan and antisulfate-soluble fraction antibody levels in mice, rabbits, and humans. Irrespective of the procedure used to elicit antibody against C. albicans antigens, mice failed to produce antimannan antibody. By contrast, all strains of mice tested produced antisulfate-soluble fraction antibody after immunization, and the magnitude of this antibody response depended on the strain of mice immunized. Rabbits readily produced antibody against both mannan and sulfate-soluble fraction when immunized by a variety of methods. Antimannan antibody was detected in 100% of sera from a randomly selected sample of 50 hospitalized patients. Only 1 of 50 patients had antisulfate-soluble fraction antibody detectable by radioimmunoassay. In pooled normal human serum, most antimannan antibody was of the immunoglobulin G class.
Role of energy metabolism in Mycoplasma pneumoniae attachment to glass surfaces
Authors: Feldner J , Bredt W , Razin S
Published: January 2020

Attachment values of Mycoplasma pneumoniae to glass are normally very low when tested in buffer containing bovine serum albumin (10 mg/ml). However, the addition of one of the metabolizable sugars glucose, fructose, or mannose increased attachment more than 10-fold. The effect was dose dependent with a distinct optimum at about 0.25 mg/ml. Higher concentrations reduced this effect. Not only the sugars themselves but also the products of their catabolism, pyruvate and phosphoenolpyruvate, enhanced attachment. Pyruvate was effective in the same range of concentrations as the sugars, whereas phosphoenolpyruvate enhanced attachment at a significantly lower concentration (0.001 mg/ml). Higher levels of these substances also resulted in a decrease of attachment. The glucose-induced increase could be partially inhibited by glucose analogs, especially by 3-O-methyl-glucopyranoside, and by various inhibitors or glycolysis. Furthermore, attachment was strongly reduced by the uncoupling agents carbonylcyanide m-chlorophenylhydrazone and 2,4-dinitrophenol, as well as by dicyclohexylcarbodiimide, an inhibitor of the membrane-bound Mg2+-adenosine triphosphatase, whereas the ionophore valinomycin increased attachment by about 30%. These findings provide strong evidence for coupling between the attachment process of M. pneumoniae to glass and the utilization of metabolic energy.
In vivo and in vitro effects of lead on humoral and cell-mediated immunity
Authors: Lawrence D A
Published: January 2020

The humoral and cell-mediated immune responses of murine lymphocytes exposed to lead in vivo and in vitro were investigated. In vivo Pb was administered via the drinking water (0 to 10 mM) for 1 to 10 weeks. In vivo exposure of the mice to Pb did not alter significantly their plaque-forming cell response to sheep erythrocytes; however, their susceptibility to Listeria infection was reduced significantly with Pb dosages of greater than 0.4 mM. Although the in vivo plaque-forming cell responses did not appear to be altered, in vitro assessment of the reactivity of these in vivo Pb-exposed lymphocytes indicated that intermediate doses enhanced, but a high dose (10 mM) was suppressive. The 10 mM in vivo Pb dose suppressed the in vitro plaque-forming cell response, the mixed-lymphocyte culture response, and lipopolysaccharide-induced proliferation, but it did not affect concanavalin A- or phytohemagglutinin-induced proliferation. Interestingly, in vitro Pb exposure (10(-6) to 10(-4) M) of murine spleen cells caused an enhancement of most activities even though these in vitro concentrations of Pb were slightly above the in vivo concentrations. Direct in vitro Pb effects on the lymphocytes could be measured, and Pb consistently enhanced humoral and cell-mediated immunity.
Local immune response to Escherichia coli pili in experimental pyelonephritis
Authors: Smith J W , Wagner S , Swenson R M
Published: January 2020

The local immune response to pili of Escherichia coli O6:K13:H1 was determined in experimental hematogenous pyelonephritis in rabbits. Pili purified from sheared cells by ammonium sulfate precipitation were found to be pure by electron microscopy and negative for lipopolysaccharide by limulus lysate assay. Antipilus antibody was detected in serum and newly synthesized protein from infected animals with enzyme-linked immunosorbent assay. Serum and local (intrarenal) antibodies were of the immunoglobulin G class, were detectable by day 20 of infection, and persisted though 250 days of infection. These data suggest that pili are present on the organism at the site of infection, since they induce the local synthesis of antipilus antibody in experimental pyelonephritis.
Investigation of a hemolysin produced by enteropathogenic Treponema hyodysenteriae
Authors: Knoop F C
Published: January 2020

A hemolysin produced by Treponema hyodysenteriae, the etiological agent of swine dysentery, was investigated. A virulent isolate (B204) was inoculated into a standard culture medium consisting of Trypticase soy broth without dextrose (BBL Microbiology Systems) supplemented with 10% fetal calf serum in an atmosphere of 70:30 deoxygenated H2-CO2. Sterile cell-free filtrates were prepared at 2-h intervals and assayed for hemolytic activity by using washed sheep erythrocytes. The maximum hemolytic titer was obtained during the early log phase of growth (4 h). A loss of hemolytic activity was observed when cell-free filtrates were stored at 23 and 4 degrees C. Storage at -20 or -80 degrees C after lyophilization resulted in retention of the hemolytic titer for periods of up to 30 days. Enzymatic inactivation of the hemolysin was accomplished with pronase, but not with deoxyribonuclease, ribonuclease, lipase, or trypsin. Addition of exogenous ribonucleic acid-core to the standard culture medium resulted in a dose-dependent increase in the amount of hemolysin produced. The hemolysin could be purified by acid and ammonium sulfate precipitation followed by ion exchange and molecular sieve chromatography. The molecular weight of the hemolysin was 68,000 when determined by sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis.
Comparison of enterotoxic activities of heat-stable enterotoxins from class 1 and class 2 Escherichia coli of swine origin
Authors: Whipp S C , Moon H W , Argenzio R A
Published: January 2020

Pig small intestine develops age-dependent resistance to some (class 2 strains) enterotoxigenic Escherichia coli while remaining susceptible to others (class 1 strains). This study tested the hypothesis that class 1 and class 2 strains produce different subtypes of heat-stable enterotoxin (ST). The dose-response curves of small intestine to crude ST preparations from a class 1 and a class 2 strain were compared in several species. In infant mice, the class 1 ST preparation was less active than the class 2 ST preparation, whereas in rabbits the preparations were equally potent. However, in 1-, 7-, and 14-week-old pigs, the class 1 ST preparation was more active than the class 2 preparation. At low doses, both preparations caused reduced absorption in pigs of all three age groups, and at high doses the class 1 preparation caused secretion in all three age groups. In contrast, at high doses the class 2 preparation caused secretion in 1-week-old pigs but only reduced absorption in older pigs. when class 1 and class 2 ST preparations were fractionated by methanol extraction, in both cases the mouse-negative, pig-positive activity was associated with the methanol-insoluble fraction and mouse-positive, pig-positive activity was associated with the methanol-soluble fraction. The results are consistent with a hypothesis that class 1 and class 2 strains of enterotoxigenic E. coli produce different subtypes of ST and that the response of pig intestine to ST varies with both age and toxin subtype.
Respective contributions to protection of primary and booster immunization with Escherichia coli heat-labile enterotoxin in rats
Authors: Klipstein F A , Engert R F
Published: January 2020

The respective contributions to protection of the route and dosage of primary and booster immunizations with Escherichia coli heat-labile enterotoxin were evaluated in rats. The degree of protection was determined by challenge with toxin and viable bacteria in ligated ileal loops, and the serum antitoxin response was assayed by enzyme-linked immunosorbent assay. Primary immunization was effective only when given by the parenteral route. The degree of protection was enhanced a fivefold dosage increase in the primary parenteral immunization in rats given constant dosages of booster immunizations either parenterally or perorally, but not by further dosage increases. In contrast, the degree of protection rose when dosages of the booster immunizations were increased over a 25-fold range. Four weekly peroral, but only two biweekly parenteral, booster immunizations were necessary to achieve strong protection; biweekly combined parenteral and peroral booster immunizations yielded both strong, immediate and extended protection. The degree of protection against the toxin correlated with that against viable bacteria and with elevated serum antitoxin titers: all seven groups with a protection index of greater than 5 against the toxin had strong protection against heat-labile toxin-producing strains and fourfold or greater increases in the antitoxin titers, whereas none of the nine groups with a protection index of less than 3 was protected against bacteria or had an equivalent antitoxin response. These observations show that once an adequate parenteral primary immunization is given, the degree of protection is influenced primarily by the dosage of the booster immunizations, the necessary number of which is dependent on their route of administration.
Monoclonal antibodies against Neisseria gonorrhoeae: production of antibodies directed against a strain-specific cell surface antigen
Authors: Nachamkin I , Cannon J G , Mittler R S
Published: January 2020

Hybridomas secreting monoclonal antibodies against an apparent strain-specific cell surface antigen of Neisseria gonorrhoeae were produced. Spleen cells from BALB/c mice immunized with whole gonococci were fused with mouse myeloma cell line Sp2/0, and hybrid cells were selected in culture. One hybridoma that secreted antibodies reactive with the immunizing strain was cloned by limiting dilution to obtain cell lines secreting monoclonal antibodies. These antibodies reacted with purified outer membranes from the immunizing strain as well as with whole gonococci. Binding of antibodies to whole gonococci was highly strain specific, with most gonococcal strains showing less than 1% of the binding with the immunizing strain. Antibodies did not bind to the other Neisseria species tested. Binding of monoclonal antibodies to whole gonococci of the immunizing strain was not dependent on state of piliation. The extent of antibody binding did vary in different colonial variants of the immunizing strain. Antibody bound to cells from colonies that were transparent or of intermediate opacity, but did not bind to cells from deeply opaque colony variants.
Molecular characterization of environmental and nontoxigenic strains of Vibrio cholerae
Authors: Kaper J B , Moseley S L , Falkow S
Published: January 2020

Environmental and nontoxigenic strains of Vibrio cholerae 0-1 were examined for genes homologous to genes encoding Escherichia coli heat-labile enterotoxin (LT). Restriction fragments encoding LT A and B subunits were isolated from the recombinant plasmid EWD299 and labeled in vitro with 32P. These probes were then hybridized to deoxyribonucleic acid extracted from strains of V. cholerae and visualized by autoradiography. None of the nontoxigenic strains of V. cholerae 0-1 from Louisiana, Alabama, Maryland, Guam, Brazil, Bangladesh, or Great Britain hybridized with the LT probes, whereas all toxigenic strains exhibited homology. In addition, strains of V. cholerae non-0-1, "group F" vibrios, V. vulnificus, and Aeromonas hydrophila were tested, and all were negative except two strains of V. cholerae non-0-1. The presence of plasmids did not correlate with toxigenicity or nontoxigenicity in any of the species examined. Thus, it appears that these strains are not simple nontoxigenic mutants, but rather do not possess any genetic material encoding cholera toxin. Such strains therefore cannot revert and serve as a reservoir of cholera.
Protection against experimental Pseudomonas aeruginosa infection in mice by active immunization with exotoxin A toxoids
Authors: Pavlovskis O R , Edman D C , Leppla S H , Wretlind B , Lewis L R , Martin K E
Published: January 2020

The immunoprophylactic effect of chemically inactivated Pseudomonas aeruginosa exotoxin A in experimental pseudomonas infections was studied. Exotoxin A toxoids were prepared by Formalin (f-TXD) or glutaraldehyde (g-TXD) treatment. Immunization of mice with three or four doses (10 micrograms each) of f-TXD and the synthetic adjuvant N-acetylmuramyl-L-alanyl-D-isoglutamine (50 micrograms) induced high levels of antiexotoxin A antibodies as measured by passive hemagglutination assay and enzyme-linked immunosorbent assay. Immunization with toxoid alone did not elicit antitoxin. A significant increase in survival time and survival rate (P less than 0.01) was seen in immunized (f-TXD) and in burned and infected mice (50 to 85%) as compared with control mice immunized with formalinized bovine serum albumin (6 to 20%). Virtually 100% survival was obtained when preinfection immunization weas combined with single-dose gentamicin treatment within 24 h of infection. Immunization with g-TXD increased survival time (P less than 0.01) but did not consistently increase survival rate, and the results were not as satisfactory as those with formalinized exotoxin. The data presented indicate that active immunization with formalinized exotoxin A toxoid and adjuvant induced protective immunity to various degrees against infections in mice and could be potentially useful in prophylaxis of P. aeruginosa infections.
Infection of Multiple T-Cell Subsets and Changes in Lymphocyte Functions Associated with
Herpesvirus saimiri
Infection of Owl Monkeys
Authors: Neubauer Russell H. , Dunn Frances E. , Rabin Harvey
Published: January 2020

We examined the association of
Herpesvirus saimiri
with lymphocyte subsets and the functional integrity and distribution of these populations in owl monkeys with chronic, disease-free infections, in uninoculated, control animals, and in one monkey with
H. saimiri
-induced lymphoma. The lymphocyte subpopulations examined included total T cells, T cells with receptors for the Fc portion of immunoglobulin G (the Tγ cells), T cells lacking this receptor (the Tγ
−
population), and non-T cells. These studies showed that in chronically infected monkeys,
H. saimiri
was found in both Tγ and Tγ
−
populations and that the relative distribution of lymphocyte subsets was not different than the relative distribution in normal animals. The peripheral blood of the one leukemic animal studied showed an increase in total T cells, and both Tγ and Tγ
−
cells were increased in number and contained recoverable
H. saimiri.
In animals with chronic infections, which previously were thought to be immunologically normal, we showed that the Tγ cells had lost the ability to respond to phytohemagglutinin. When the level of nonspecific cytotoxic activity was examined, we found that the lymphocytes from infected animals were as active as those from uninfected monkeys and that this activity was maintained at normal levels during disease. In the leukemic blood there was a relative increase in the cytotoxic activity of the Tγ
−
cells. The Tγ
−
cells obtained from leukemic blood lacked the ability to respond to phytohemagglutinin and could suppress the phytohemagglutinin response of normal cells. This suppressor cell activity was resistant to 3,000 rads of X irradiation. We also found that cells reactive to
H. saimiri
antigens could be demonstrated in the lymph nodes but not in the peripheral circulation of the lymphomatous monkey.