bluuebunny/crossref_metadata_2025 huggingface dataset:
Biological characterization of avian osteopetrosis
Authors: Banes A J , Smith R E
Published: January 2020

Chicks infected as 12-day-old embryos with an end-point purified derivative of avian myeloblastosis virus developed a rapidly progressive osteopetrosis that manifested within 1 week of hatching. A detailed comparison of osteopetrotic chicks and normal hatchmates revealed the following. (i) Osteopetrotic chicks exhibited a stunting syndrome, growing at a mean rate that was 26% of the control rats. (ii) At autopsy, the mass of the lymphoid organs was reduced, whereas the mass of the heart, pancreas, kidneys, lungs, brain, liver, and bones of osteopetrotic chicks was increased. Edema was likely responsible for most of the increase in organ weight. (iii) Infected chicks exhibited a normochromic, normocytic anemia that was virus dose dependent and was not required for the development of osteopetrosis. (iv) Bone collagen content was normal. (v) Osteopetrotic bone was initially hypomineralized, but later became more fully mineralized. (vi) The concentrations of alpha, beta, and gamma globulins in the plasma were elevated in osteopetrotic chicks, whereas albumin concentration was decreased. (vii) The level of plasma alkaline phosphatase was elevated in osteopetrotic chicks, yet the level of acid phosphatase was unchanged. (viii) Body and bone temperatures were unchanged.
Development of cell-mediated immunity to Epstein-Barr herpesvirus in infectious mononucleosis as shown by leukocyte migration inhibition
Authors: Lai P K , Alpers M P , MacKay-Scollay E M
Published: January 2020

Eight patients with infectious mononucleosis, aged between 8 and 24, were studied for cell-mediated immunity by the in vitro leukocyte migration inhibition test at acute and convalescent stages. Follow-up studies were also carried out at up to 4 months after clinical illness. Cell-mediated immunity to Epstein-Barr virus (EBV) in the peripheral leukocytes from these patients was absent or incipient in all cases during the acute phase, although it was present in lymphocytes from a biopsied lymph node obtained from one of the patients. In contrast, cell-mediated immunity to EBV was detected readily in peripheral leukocytes obtained during convalescence and in the follow-up studies. A blocking factor that abrogated leukocyte migration inhibition induced by EBV antigen was detected in acute and convalescent sera obtained from six of eight patients, whereas serum antinuclear autoantibodies were detected in the two patients whose sera failed to block leukocyte migration inhibition. When sera were fractionated, this blocking effect was observed only in the serum immunoglobulin G fractions. In follow-up studies, neither the blocking factor nor the antinuclear autoantibodies were found in the sera collected.
Protective capacity of antibodies against Escherichia coli and K antigens
Authors: Kaijser B , Ahlstedt S
Published: January 2020

Antibodies to Escherichia coli O and K antigens were raised in rabbits by repeated immunizations with whole, Formalin-killed and, later, liver bacteria. The serum antibody levels were determined with the ammonium sulfate precipitation technique after radioiodinating the antigens. The K antigens had to be conjugated to proteins before labeling. Such conjugations were performed using cyanogen bromide for the K1 antigen and bisdiazobenzidine for the K13 antigen. The protective capacities of the rabbit antisera were tested in intraperitoneally infected mice. The protective capacity of the antisera was expressed per ammonium sulfate precipitation titer. The results showed a significantly higher protective effect for the antibodies against the K1 and K13 antigens than for the antibodies against the O2 and O6 lipopolysaccharides.
Kinetics of Phagocytosis and Intracellular Killing of
Candida albicans
by Human Granulocytes and Monocytes
Authors: Leijh P. C. J. , van den Barselaar M. T. , van Furth R.
Published: January 2020

The study of the phagocytosis and intracellular killing of
Candida albicans
by granulocytes and monocytes has been hampered by the budding and pseudomycelium formation of this yeast during a relatively short incubation period at 37°C and by the similar density of candida cells and phagocytes, which makes differential centrifugation impossible. In the present study,
C. albicans
was used after 5 days of preculture at 30°C, after which the number of candida cells remained constant during incubation at 37°C for 90 min. On this basis, phagocytosis and intracellular killing were limited to a period of 60 min. Phagocytosis of
C. albicans
by granulocytes and monocytes was measured with a hemocytometer, the number of extracellular candida being a measure of the ingestion of these microorganisms. After 60 min, 96% of the candida cells were ingested by normal human granulocytes and monocytes. This process was dependent on the opsonin concentration and temperature and was inhibited by mono-iodoacetic acid. Heat-inactivated serum was less active than fresh serum, reflecting the role of complement factors with respect to opsonization. Intracellular killing was measured by a microbiological assay. After 60 min of incubation of phagocytes together with
C. albicans
and serum, human granulocytes and monocytes killed 58 and 50% of the ingested candida, respectively. This process was inhibited by phenylbutazone. Phagocytes from patients with chronic granulomatous disease showed impaired intracellular killing.
Enhanced susceptibility of mice to combinations of delta 9-tetrahydrocannabinol and live or killed gram-negative bacteria
Authors: Bradley S G , Munson A E , Dewey W L , Harris L S
Published: January 2020

Combinations of delta 9-tetrahydrocannabinol (delta 9-THC) and bacterial endotoxin were shown to be hyperadditively toxic for mice. A variety of purified lipopolysaccharide (LPS) preparations elicted enhanced mortality in combination with delta 9-THC. Escherichia coli O26:B6 LPS (Boivin preparation) at an essentially nonlethal dose of 2.5 mg/kg reduced the dose of delta 9-THC required to kill 50% of the treated mice from ca. 350 to 150 mg/kg. Inbred BALB, DBA, and C3H/HeCr mice, noninbred ICR mice, and hybrid CDF1 and BDF1 mice were hyperreactive to combinations of delta 9-THC and LPS. Moreover, a variety of heat-killed intestinal and gram-negative bacteria, live E. coli, and complexes of lipid A with a variety of proteins substituted for LPS in the synergistic toxicity of LPS and delta 9-THC. Extracts of marijuana also elicited hyperreactivity to LPS. The hyperadditive lethality of combinations of delta 9-THC and LPS was markedly less in mice rendered refractory to LPS or delta 9-THC by repeated administration of LPS or delta 9-THC, respectively.
Regulation of endotoxin-induced inhibition of macrophage migration by fresh serum
Authors: Heilman D H
Published: January 2020

Purified endotoxin (LPS) caused macrophage migration inhibition (MMI) in capillary tube cultures of guinea pig peritoneal macrophages in medium prepared with 15% fresh-frozen guinea pig serum. The inactivation of serum by heating at 56 degrees C for 30 min or by zymosan absorption prevented LPS-induced MMI. LPS was fully inhibitory in fresh C4-deficient guinea pig serum. Heat treatment of normal serum at 50 to 52 degrees C for 30 min to inactivate the alternate complement (C) pathway prevented or significantly decreased LPS-induced MMI, but heating C4-deficient serum at 50 to 52 degrees C for 30 min prevented LPS-MMI in all instances. These results suggest that the reaction was effected via the alternate C pathway but that some inhibition of migration was permitted via the classical C pathway, presumably due to antibodies for LPS in some normal sera. Pretreatment of normal serum with cobra venom factor decreased or prevented LPS-MMI in most instances, but similar results were obtained with C4-deficient serum. Experiments with chelated sera were unsuccessful because of the immobilization of macrophages by 10 mM ethylenediamine-tetraacetic acid and by 10 mM Mg-ethyleneglycol-bis (beta-aminoethyl)-N,N-tetraacetic acid. Low doses of concanavalin A and staphylococcal enterotoxin B and large doses of pokeweed mitogen caused MMI in "inactivated serum" medium, but MMI was enhanced in fresh serum.
Preparative polyacrylamide gel electrophoresis purification of Clostridium perfringens enterotoxin
Authors: Enders G L , Duncan C L
Published: January 2020

Preparative polyacrylamide gel electrophoresis has been used to purify the enterotoxin of Clostridium perfringens from Sephadex G-100 extracts. Purified toxin of high specific activity was eluted in 1 to 3 h, depending upon the length of the acrylamide gel used. Recovery of biological activity with this technique ranged from 80 to 90%. The purity and physical characteristics of the toxin were similar to those previously reported for the protein purified by other methods. Use of preparative electrophoresis will enable the production of larger amounts of high-specific-activity toxin in a shorter time than other currently available procedures. This method was also used to isolate a form of enterotoxin that has a mobility, relative to bromophenol blue tracking dye, of 0.87 to 0.90 in 7% acrylamide gels.
Differences in mouse interferons according to cell source and mode of induction
Authors: Maehara N , Ho M , Armstrong J A
Published: January 2020

Mouse interferon induced by ultraviolet-irradiated Newcastle disease virus or polyriboinosinic-polyribocytidylic acid in T lymphocytes, B lymphocytes, macrophages, and primary mouse embryonic cell culture was studied. Irrespective of the inducer, interferons produced by T or B lymphocytes were relatively heat stable and of low antigenicity when reacted with antiserum against L-cell interferon (ALI), whereas interferons produced by macrophages and mouse embryo cells were heat labile and of high antigenicity against ALI. Mouse interferons induced by ultraviolet-irradiated Newcastle disease virus were separated into three components by chromatography on CH-Sepharose 4B. Interferons produced by T and B lymphocytes consisted primarily of component 1 (unbound fraction), whereas interferons produced by macrophages or mouse embryo cells consisted primarily of component 3 (eluted by 0.5 M NaCl). Component 1 was heat stable and of low antigenicity against ALI, properties characteristic of T- and B-cell interferon. Components 2 and 3 were heat labile and of high antigenicity against ALI, properties characteristic of macrophage and mouse embryo cell interferon. In contrast, interferon induced in mice sensitized with BCG differed from these interferons induced in B cells, T cells, macrophages, and fibroblasts in being extremely acid labile and nonreactive against ALI.
Immunological Interrelationships Between Cholera Toxin and the Heat-Labile and Heat-Stable Enterotoxins of Coliform Bacteria
Authors: Klipstein Frederick A. , Engert Richard F.
Published: January 2020

Cholera toxin (CT) and the heat-labile (LT) toxin of
Escherichia coli
are known to share antigenic properties. The present study examined the immunological relationship of CT and the LT and heat-stable (ST) toxins of
E. coli, Klebsiella pneumoniae
, and
Enterobacter cloacae
. The neutralizing capacity of equine CT antiserum and of antiserum raised in rabbits to the LT toxin of the three species of coliform bacteria was evaluated by determining their capacity to inhibit the action of purified CT and semipurified ultrafiltration preparations of the coliform LT and ST toxins in inducing water secretion as assayed by the in vivo marker perfusion technique in the rat jejunum. One milliliter of antiserum to CT and to
E. coli
and
Klebsiella
LT completely neutralized the secretory action of each of these three toxins; effective serial dilutions of CT antiserum extended to 1 to 4, whereas those of the antisera to LT were limited to 1 to 2 in most instances. One milliliter of antiserum to
E. cloacae
LT partially neutralized each of the three coliform LT toxins; serial dilutions were inactive. Antiserum to
E. cloacae
LT did not neutralize CT. Antiserum to CT and to each of the three coliform LT toxins also had a weak neutralizing effect on the ST toxins of
E. coli
and
Klebsiella
, but they did not affect
E. cloacae
ST. Adsorption of the antiserum to CT and to each of the three LT toxins by incubation with a heat-inactivated preparation of either the homologous or a heterologous LT toxin completely abolished the neutralizing capacity of the antisera towards both LT and ST. These observations indicate that the immunological interrelationship of CT and
E. coli
LT extends to the LT toxins of
Klebsiella
and
E. cloacae
and, further, that these immunological properties are shared to a lesser extent by the ST toxins of
E. coli
and
Klebsiella.
Sequential Changes in Cell-Mediated Immune Responses to Herpes Simplex Virus After Recurrent Herpetic Infection in Humans
Authors: Shillitoe E. J. , Wilton J. M. A. , Lehner T.
Published: January 2020

Lymphocyte responses to herpes simplex virus (HSV) were studied in 23 patients with recurrent herpes labialis and in 19 control subjects. Lymphocytes of seropositive, but not seronegative, controls responded to HSV by thymidine incorporation, and the supernatant fluids inhibited the migration of guinea pig macrophages. Lymphocytes from patients with a recurrent herpetic lesion responded to HSV by significantly greater thymidine incorporation than seropositive controls, but supernatants did not show an increased macrophage migration inhibition response. During the 28 days after the onset of a lesion, the thymidine incorporation to HSV fell to the level of the seropositive controls, and supernatants then induced an increased inhibition of macrophage migration. Lymphocyte responses to
Candida albicans
, purified protein derivative, or phytohemagglutinin did not fluctuate according to the presence of a lesion and did not differ from those of the controls. Lymphocyte responses to HSV were unaffected by culture in the presence of serum from seronegative or seropositive controls, or from patients with or without a herpetic lesion. It is suggested that in patients with recurrent herpes labialis a periodic defect of the migration inhibition response might have allowed the recurrent infection to develop, and that the increased thymidine incorporation stimulated by HSV in vitro is a result of antigenic stimulation from the lesion.
Isolation from corynebacterium diphtheriae C7(beta) of bacterial mutants that produce toxin in medium with excess iron
Authors: Kanei C , Uchida T , Yoneda M
Published: January 2020

Five mutants that produce toxin in medium with excess iron were isolated from strain C7(beta). The iron content of bacteria grown on this medium was considerably higher than that of C7(beta) cells grown in medium containing the minimum amount of iron needed to inhibit toxin production. When the nonlysogenic, nontoxinogenic strain C7(-) was lysogenized with phages from each of the mutants, toxin production by all of the resulting lysogens, like that by parent strain C7(beta), ceased upon iron addition. When the mutants were superinfected with beta45 phage, both toxin and CRM45 were produced in medium with excess iron. One of the mutant strains lost its prophage as a result of treatment with ultraviolet light. When the cured strain was lysogenized with phage carrying a mutation in the tox structural gene, the lysogen produced the mutant protein at the maximum rate in medium with excess iron. These findings show that the mutant strains are not phage mutants, but are bacterial host mutants, and that a host factor(s) is involved in the inhibition of toxin production by iron.
Cell envelope of Neisseria gonorrhoeae: relationship between autolysis in buffer and the hydrolysis of peptidoglycan
Authors: Wegener W S , Hebeler B H , Morse S A
Published: January 2020

Neisseria gonorrhoeae readily underwent autolysis when suspended in N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) buffer at alkaline pH values. Autolysis was inhibited by the addition of Mg2+ or other divalent cations. Autolysis was also suppressed at acid pH (pH 6.0). Suspension of cells in buffer was accompanied by the hydrolysis of peptidoglycan. The rate of peptidoglycan hydrolysis in HEPES buffer was maximal at pH 8.5 and was similar in the presence or absence of Mg2+. Therefore, divalent cation stabilization against autolysis is not mediated by inhibition of peptidoglycan hydrolysis. Peptidoglycan hydrolysis occurred in HEPES buffer (pH 6.0), but at a rate that was 50% of the maximum. Incubation of cells with chloramphenicol or rifampin before suspension in HEPES buffer (pH 8.5) partially prevented autolysis; under these conditions, peptidoglycan hydrolysis still occurred, but at a reduced rate. Old and new peptidoglycans were hydrolyzed at similar rates. Peptidoglycan hydrolysis results in solubilization of both the peptide and glycan moieties.
Detection and differentiation of iron-responsive avirulent mutants on Congo red agar
Authors: Payne S M , Finkelstein R A
Published: January 2020

Agar medium containing Congo red dye differentiates virulent and avirulent colonies of Shigella, Vibrio cholerae, Escherichia coli, and Neisseria meningitidis. Like virulent plague bacilli, wild-type cells of these species absorb the dye and produce red colonies. Mutants or colonial variants have been isolated that fail to absorb the dye and produce colorless colonies. These mutants exhibit reduced virulence in the chicken embryo model, but their virulence is enhanced by supplementation with iron. Of those species tested, only Neisseria gonorrhoeae isolates failed to grow in the presence of this dye. Inhibition of growth by Congo red may thus provide a simple means for differentiating gonococci from other Neisseria.
Trypanosoma rhodesiense infection in B-cell-deficient mice
Authors: Campbell G H , Esser K M , Weinbaum F I
Published: January 2020

B-cell-deficient C57B1/6J mice (suppressed from birth with goat anti-mu) and controls (treated from birth with normal goat serum) were infected with Trypanosoma rhodesiense. There was a significant (P less than 0.01) decrease in duration of survival of the mu-suppressed mice compared with that of controls. Whereas both mu-suppressed and control mice had an initial rise in parasitemia of similar magnitude, only the control mice exhibited a subsequent period during which the parasitemia fell to undetectable levels. In control mice, immunization with irradiated organisms prevented the development of detectable parasitemia after challenge with viable trypanosomes. However, immunization did not alter the course of infection in B-cell-deficient mice. These results indicate that immunity to T. rhodesiense infection in mice is dependent on B-cell immunocompetence.
Detection of hepatitis A antigen by immunofluorescence
Authors: Mathiesen L R , Feinstone S M , Purcell R H , Wagner J A
Published: January 2020

Hepatitis A antigen (HA Ag) was demonstrated by immunofluorescence (IF) in liver biopsies from chimpanzees with experimental hepatitis A virus infection. Blocking experiments with paired sera from patients with hepatitis types A, B, or non-A, non-B, as well as with purified HA Ag, showed that the fluorescence was specific for HA Ag. HA Ag could be demonstrated only in biopsies from chimpanzees inoculated with hepatitis A virus. In two of four chimpanzees biopsied weekly, HA Ag could be detected by IF before stool shedding of HA Ag, elevation in serum alanine aminotransferase (SGPT), or histopathological evidence of liver disease was seen. The HA Ag was detected for 4 to 5 weeks; the last IF-positive biopsy was obtained after SGPT activity had returned to normal. In the two other chimpanzees, HA Ag could be detected only in the biopsy taken at the time of SGPT elevation. In the early IF-positive biopsies, HA Ag was diffusely distributed in the cytoplasm of many cells, but it later accumulated in a focal distribution in the cytoplasm of a few of the hepatocytes and Kupffer cells. This cytoplasmic distribution agrees with previous electron microscopic data.
Immunological relatedness of papovaviruses of the simian virus 40-polyoma subgroup
Authors: Shah K V , Daniel R W , Kelly T J
Published: January 2020

Viral antigens in permissive cells infected with JC virus, K virus, and SA12 virus were reactive in immunofluorescence tests to antisera against sodium dodecyl sulfate-disrupted simian virus 40 capsids and polyoma VP1. The major capsid polypeptides of all papovaviruses of the simian virus 40-polyoma subgroup are immunologically related.
Fluoride uptake by Streptococcus mutans 6715
Authors: Whitford G M , Schuster G S , Pashley D H , Venkateswarlu P
Published: January 2020

The short-term kinetics of fluoride uptake by cells from 20- to 22-h cultures of Streptococcus mutans strain 6715 were studied using rapid filtration and centrifugation techniques. Saline-suspended organisms were diluted with fluoride-containing solutions buffered at four different pH values (2.0, 4.0, 5.5, and 8.2). Fluoride disappearance from the medium was inversely related to pH and to the duration of the exposure at any given pH. The uptake was rapid and extensive at the lower pH values and decreased as the pH increased. Media fluoride concentrations subsequently increased; i.e., fluoride was released from the cells. The presence of glucose, cyanide, or iodoacetate did not influence the results. However, preincubation of the cells in fluoride-free buffers, followed by the addition of fluoride, reduced fluoride uptake markedly. Cell-to-media pH gradients were determined by the distribution of 14C-labeled 5,5-dimethyl-2,4-oxazolidinedione. Fluoride uptake was found to be a function of the magnitude of the pH gradient (P less than 0.001). It is hypothesized that fluoride uptake occurs by the diffusion of hydrogen fluoride and the subsequent trapping of ionic fluoride.
Effects of streptolysin O on transport of amino acids, nucleosides, and glucose analogs in mammalian cells
Authors: Duncan J L , Buckingham L
Published: January 2020

The transport of several amino acids, nucleosides, and glucose analogs was studies in HeLa cells treated with sublethal concentrations of streptolysin O. A differential effect of toxin on the various solutes tested was observed. The uptake of the neutral amino acids alanine, alpha-aminoisobutyric acid, leucine, and phenylalanine was reduced by 60 about to 70%. Less inhibition of transport was observed with acidic and basic amino acids, and the uptake of nucleosides and glucose analogs was reduced by 20% or less. The decreased uptake of alpha-aminoisobutyric acid could be explained by the inability of toxin-treated cells to retain this amino acid. The altered transport of phenylalanine and lysine, however, appeared to be due to decreased initial rates of uptake rather than to the loss of these amino acids from intracellular pools in toxin-treated cells. After treatment with sublethal concentrations of streptolysin O, the cells recovered their ability to transport and accumulate alpha-aminoisobutyric acid in about 4 h. The data suggest that the alterations in membrane transport observed in toxin-treated cells are due to an effect of streptolysin O on specific transport systems, rather than to the production of holes or pores in the membrane.
Alteration of host defense mechanisms by murine cytomegalovirus infection
Authors: Kelsey D K , Olsen G A , Overall J C , Glasgow L A
Published: January 2020

An animal model of a sublethal infection, utilizing murine cytomegalovirus (MCMV), was developed to determine whether immunological factors could contribute to the establishment of a persistent viral infection. Adult female C3H mice inoculated intraperitoneally with 10(5) plaque-forming units of MCMV developed splenomegaly 5 to 12 days after infection. Virus replicated to peak titers (10(3) to 10(6) plaque-forming units per g of tissue) in liver, spleen, lung, kidney, and salivary gland tissue during the acute phase of the infection (3 to 12 days); it then decreased to undetectable levels in all tissues except salivary gland. Serum interferon was detected as early as 12 h after infection, peaked at 36 h (1,093 U/ml), and was undetectable by 4 days after infection. MCMV-infected animals were hyporeactive to interferon induction with New castle disease virus on days 5 to 9 of the infection. Splenic lymphocyte reactivity to phytohemagglutinin and lipopolysaccharide was normal early during the course of the infection, was suppressed during the acute phase of the infection, and had returned to normal by day 18. These data indicate that several parameters of host defense are transiently suppressed during the course of a MCMV infection. The capacity of cytomegaloviruses to alter host resistance may be one factor that contributes to the establishment of a persistent infection.
Antibody response in rabbits to immunization with Mycobacterium leprae
Authors: Harboe M , Closs O , Bjorvatn B , Kronvall G , Axelsen N H
Published: January 2020

Mycobacterium leprae purified from liver tissue of an infected armadillo (the A/10 preparation) was tested for antigenic composition by immunization of rabbits and characterization of the antibody response by crossed immunoelectrophoresis. The rabbit antisera detected seven distinct components in the M. leprae preparation. This number is far lower than in similar experiments with other mycobacteria. The M. leprae sonic extract gave far fewer lines after polyacrylamide gel electrophoresis and staining with Coomassie brillant blue than sonic extracts prepared from BCG, M. smegmatis, and M. phlei adjusted to the same protein concentration based on the Folin assay. The seven components detected in M. leprae cross-reacted extensively with M. avium, BCG, M. lepraemurium, M. smegmatis, and Nocardia asteroides. The seven components are involved in immune reactions in leprosy; antibodies against all of them were demonstrated in sera from patients with lepromatous leprosy, but the specificity of the antibodies varied from patient to patient. The reason for the demonstration of so few antigenic components and some of the implications of these findings for the use of armadillo-grown M. leprae to develop specific skin test reagents and in other aspects of leprosy research are discussed.
Epidemic caprine keratoconjunctivitis: recovery of Mycoplasma conjunctivae and its possible role in pathogenesis
Authors: Baas E J , Trotter S L , Franklin R M , Barile M F
Published: January 2020

Clinical, microbiological, serological, histological, and therapeutic aspects of two separate outbreaks of caprine keratoconjunctivitis are described. The disease was characterized by a high rate of contagion, rapid onset, intense lacrimation, conjunctival hyperemia, and corneal opacity with neovascularization. In addition, many of the animals developed respiratory illness during the second epidemic. The only organism consistentlyisolated was Mycoplasma conjunctivae. A total of 23 strains were isolated from 18 inflamed conjunctivae, one normal conjunctiva, and the nasal secretions of four goats with concomitant respiratory illness. The convalescent sera of goats in the first outbreak had neutralizing antibody titers to M. conjunctivae that ranged from 1:32 to 1:256. In the milder second outbreak the antibody titers ranged from 1:4 to 1:32 in animals with only ocular disease and from 1:4 to 1:64 in animals with only respiratory disease. Whereas little change was noted in antibody titers of goats with only localized eye disease, 43% of the goats with respiratory disease showed significant fourfold rises. The histological picture was consistent with acute corneal infection. Animals requiring antibiotic treatment appeared to respond favorably to a combination of oxytetracycline and polymyxin B, but not to penicillin. These findings suggest that M. conjunctivae is one cause of epidemic caprine keratoconjunctivitis.
Experimental Rat model for Corynebacterium renale-induced pyelonephritis
Authors: Jerusik R J , Kadis S , Chapman W L , Wooley R E
Published: January 2020

The laboratory rat was able to serve as a model for ascending pyelonephritis after implantation of a zinc disk coated with Corynebacterium renale into the urinary bladder because it satisfied three different criteria for infection. The production of an alkaline urine and the presence of significant numbers of C. renale in the kidneys, as well as distinct pyelonephritic lesions as revealed by histological examination, were observed in all rats infected with C. renale. Control rats that harbored sterile disks in their urinary bladders exhibited none of the above effects.
Bactericidal Activity of Specific and Azurophil Granules from Human Neutrophils: Studies with Outer-Membrane Mutants of
Salmonella typhimurium
LT-2
Authors: Rest Richard F. , Cooney Marjorie H. , Spitznagel John K.
Published: January 2020

Extracts of specific granules and azurophil granules from human neutrophils were tested for their bactericidal activity against various lipopolysaccharide mutants of
Salmonella typhimurium
LT-2. Three purified granule populations, one specific and two azurophil, were obtained by isopycnic centrifugation of homogenized neutrophils. Each was extracted with 0.2 M acetate buffer (pH 4), and the extracts were dialyzed against phosphate-buffered saline (pH 7) to remove acetate. These extracts contained ≥84% of the lysozyme, lactoferrin, or myeloperoxidase initially present in the whole granules. The
S. typhimurium
mutants possessed Ra, Rc, Rd
1
, Rd
2
, or Re lipopolysaccharide. As the carbohydrate content of the lipopolysaccharide decreased, the bacteria became increasingly more susceptible to the bactericidal activity of all granule extracts. Bactericidal activity of the extracts was in the order: mixed (azurophil + specific) ≥ azurophil » specific. Specific granules were bacteriostatic for S through Rd
2
bacteria. They were bactericidal only for the Re mutant. Both azurophil granule populations were equally bactericidal. Extracts boiled for 30 min retained none of their bactericidal activity for any of the bacteria; however, they remained bacteriostatic for the deep rough (Rd
2
, Re) mutants. Bactericidal activity was dependent upon pH, in that mixed and azurophil granule contents killed the smooth parent and Ra mutant best at pH 5, the Rc and Rd
1
mutants to the same degree at pH 5 to 8, and the deep rough mutants (Rd
2
and Re) best at pH 8. Specific granule contents were most bacteriostatic for S through Rd
2
bacteria at pH 5 and killed the Re mutant only at pH 8. Thus, as the
S. typhimurium
lipopolysaccharide content decreased, the bactericidal pH optimum increased. Killing by all extracts was dependent upon incubation temperature, with almost no bactericidal or bacteriostatic activity observed when bacteria and granule fractions were incubated on ice (2°C) and plated immediately. Intermediate killing was observed at 22°C. If bacteria were incubated with granule extracts at 2°C, washed free of extract, suspended in medium without extract, and reincubated at 37°C, killing was observed. This suggested that a component(s) of the extracts was sticking to the bacteria at 2°C but killing only at 37°C.
Limits of rickettsial infectivity
Authors: Ormsbee R , Peacock M , Gerloff R , Tallent G , Wike D
Published: January 2020

Seven species of pathogenic rickettsiae were compared in five assay systems for group, species, strain, and phase differences in infectivity. The species examined include Rickettsia prowazekii (Breinl and Cairo 3 strains), R. typhi, R. canada, R. rickettsii (Sheila Smith and R strains), R. conorii, R. sibirica, and Coxiella burnetii in phases I and II. Pathogenicity was charcterized in terms of fever in guinea pigs. All comparisons of infectivity and pathogenicity were described in terms of numbers of rickettsiae in the inocula, as determined by direct rickettsial count. The data characterize the various species and strains of rickettsiae in quantitative terms, which are also estimates of the sensitivity of the assay systems used. Phase I C. burnetii was found to be the most, and R. canada the least, infective of the species examined. In general the primary chicken embryo cell culture system proved to be the most, and that of the mouse the least, sensitive assay system.
Mechanism of action of Pseudomonas aeruginosa exotoxin A in experimental mouse infections: adenosine diphosphate ribosylation of elongation factor 2
Authors: Pavlovskis O R , Iglewski B H , Pollack M
Published: January 2020

The data presented indicate that one of the primary actions of Pseudomonas aeruginosa exotoxin during experimental infection is the inactivation of elongation factor 2 (EF-2) in various mouse organs. Organs from mice infected with the toxigenic P. aeruginosa strain PA103 contained considerably less EF-2 activity than did organs from uninfected controls. Whereas EF-2 activity was reduced in all organs examined from PA103-infected animals, the largest decrease was observed in the liver, where the active EF-2 levels were reduced by 70 to 90%. In addition, consistent inhibition of protein synthesis in livers but not in other organs was observed in mice infected with the toxigenic PA103 strain. Treatment of mice with antitoxin before infection with strain PA103 prevented inactivation of EF-2. When mice were infected with lethal doses of the nontoxigenic P. aeruginosa WR5 strain, tissue EF-2 levels were not markedly reduced below those derived from uninfected control animals.
Induction of cell-mediated immunity to Mycobacterium leprae in mice
Authors: Patel P J , Lefford M J
Published: January 2020

The immune response of mice to armadillo-derived, irradiation-killed Mycobacterium leprae (I-ML) was investigated. Following injection of 100 microgram of I-ML into the left hind footpads of mice, a state of cell-mediated immunity (CMI) was engendered to antigens of M. leprae. The evidence for CMI was as follows: (i) development of delayed-type hypersensitivity to both human tuberculin purified protein derivative and soluble M. leprae antigens; (ii) T-lymphocyte-dependent macrophage activation at the inoculation site; (iii) specific systemic resistance to the cross-reactive species M. tuberculosis; and (iv) immunopotentiation of the delayed-type hypersensitivity response to an unrelated antigen. The CMI induced by I-ML in aqueous suspension was greater than that obtained with the same antigen in water-in-oil emulsion, even though the latter generated a more severe reaction at the site of immunization. I-ML also induced a stronger CMI response than the corresponding dose of heat-killed BCG.
Use of Semliki forest virus to identify lipid-mediated antiviral activity and anti-alphavirus immunoglobulin A in human milk
Authors: Welsh J K , Skurrie I J , May J T
Published: January 2020

In a simple and reliable assay system, Semliki forest virus (SFV) was used to detect the activity of antiviral factors in human milk. Fractionation of the milk showed that a heat-stable, lipid-associated activity and an immunoglobulin-associated activity were present, either singly or together, in 85% of the human milk samples tested. Cow and synthetic milk showed neither activity. Extraction of the neutral milk lipids allowed the antiviral to be located with the monoglyceride and free fatty acid fractions. The milk low in antiviral lipids and high in triglycerides also lacked a strong lipase activity. The immunoglobulin anti-SFV activity was shown to be due to immunoglobulin A, the major milk immunoglobulin, and appears to be directed against an alphavirus closely related to SFV, possibly Ross River virus.
Use of an alkali-soluble water-soluble extract of Blastomyces dermatitidis yeast-phase cell walls and isoelectrically focused components in peripheral lymphocyte transformations
Authors: Hall N K , Deighton F , Larsh H W
Published: January 2020

An alkali-soluble water-soluble extract of Blastomyces dermatitidis yeast-phase cell walls was tested for its ability to elicit a response in lymphocytes isolated from the peripheral blood of Blastomyces-infected guinea pigs. Sequential preparations of the antigen were reproducible and specific in the in vitro lymphocyte transformation assay. Cross-reactivity of the antigen was not evident in lymphocyte transformation assays on lymphocytes obtained from Histoplasma-infected guinea pigs or from animals sensitized with complete Freund adjuvant. Fractionation of the antigen was accomplished on an isoelectric-focusing column, using a sucrose density gradient support. Components were assayed for activity in skin testing and lymphocyte transformation. Comparison of column fractions to the whole antigen showed greater response to the whole antigen in in vivo and in vitro assays.
Host Defenses in Experimental Scrub Typhus: Genetics of Natural Resistance to Infection
Authors: Groves Michael G. , Osterman Joseph V.
Published: January 2020

Genetic resistance to lethal infection with
Rickettsia tsutsugamushi
was studied in over 30 inbred strains, inbred hybrids, and outbred stocks of mice. Inbred mice infected intraperitoneally with the Gilliam strain of
R. tsutsugamushi
showed three patterns of response: susceptible (A/HeJ, C3H/HeDub, C3H/HeJ, C3H/HeN, C3H/St, CBA/J, DBA/1J, DBA/2J, and SJL/J), resistant (AKR/J, BALB/cDub, BALB/cJ, C57BL/6J, C57L/J, and SWR/J), and selectively resistant (A/J). The selectively resistant pattern was characterized by random deaths occurring throughout the titration range and was also observed in three of the six outbred mouse stocks surveyed. No correlation was evident between the H-2 haplotype of inbred mice and their response to Gilliam infection. The progeny from five different Gilliam-resistant by Gilliam-susceptible inbred parental crosses were all resistant. Study of F
1
, F
2
, and parental backcross generations of BALB/cDub (resistant) and C3H/HeDub (susceptible) hybrids indicated resistance was dominant and was controlled by a single gene or a closely linked cluster of genes that were autosomal and not linked to coat color. The resistance of BALB/cDub mice was not due to an inability of host cells to support rickettsial growth, since C3H/HeDub and BALB/cDub embryo cell cultures supported similar growth of Gilliam organisms. C3H/HeDub mice, although susceptible to intraperitoneal Gilliam infection, were capable of mounting an immune response to Gilliam antigens, since subcutaneous infection was not lethal and did protect animals against subsequent intraperitoneal challenge with either the Gilliam or Karp strains of
R. tsutsugamushi.
Contribution of immunoglobulins M and G, complement, and properdin to the intracellular killing of Escherichia coli by polymorphonuclear leukocytes
Authors: Menzel J , Jungfer H , Gemsa D
Published: January 2020

The effect of immunoglobulins and complement (C) on phagocytosis and intracellular killing of Escherichia coli was studied in vitro. The incubation system consisted of monolayers of human polymorphonuclear leukocytes and C-resistant, [3H]thymidine-labeled E. coli C source was human serum deprived of immunoglobulins and properdin by immunoabsorption. In the absence of C, only immunoglobulin G-coated bacteria were phagocytosed, whereas immunoglobulin M lacked opsonic activity. In the presence of C, phagocytosis was enhanced; however, immunoglobulin M was now more efficient than immunoglobulin G. Intracellular killing was notably augmented when C was activated by immunoglobulin G- or immunoglobulin M-coated bacteria; in contrast, the alternative activation of C by properdin had no effect on phagocytosis or intracellular killing. These results demonstrate the importance of immunoglobulins together with C not only for phagocytosis but also for efficient intracellular killing.
Immunoglobulins and secretory component in the external secretions of foals with combined immunodeficiency
Authors: Buening G M , Perryman L E , McGuire T C
Published: January 2020

Nasal washings and tears were collected from seven Arabian foals with combined immunodeficiency and nine normal foals. The major immunoglobulin in the external secretions of normal foals over 2 months of age was secretory immunoglobulin A, whereas foals with combined immunodeficiency lacked this immunoglobulin. The external secretions of both normal and immunodeficient foals contained free secretory component at birth.
Observation of beta-hemolysis among three strains of Streptococcus mutans
Authors: Wolff L , Liljemark W F
Published: January 2020

Streptococcus mutans is normally alpha- or gamma-hemolytic on blood agar plates. However, three recently isolated S. mutans strains were observed to elicit beta-hemolysis. The production and nature of a hemolytic substance were studied.
Isolation of glycopeptides with skin test activity from dermatophytes
Authors: Moser S A , Pollack J D
Published: January 2020

By using ethylene glycol extraction of whole submerged cultures followed by Sephadex G-200 and diethylaminoethyl-Sephadex chromatography, we isolated four distinct glycopeptides from Trichophyton mentagrophytes, T. rubrum, and Microsporum canis. Chemical analyses revealed that these glycopeptides contained mostly carbohydrate (42.5 to 81.6%) and protein (4.3 to 11.3%), with lesser amounts of phosphorus (0.4 to 6.0%) and hexosamines (0.3 to 0.6%). Based upon total carbohydrate and monosaccharide content, these dermatophyte glycopeptides could be divided into two chemical groups: glucopeptides (DSI1) and mannopeptides (DSI2, DSII1, and DSII2). The mannopeptides and glucopeptides of each species of dermatophyte were not significantly different chemically from those derived from the other two dermatophyte species studied. Skin testing of DSI1-glycopeptides or DSI2-mannopeptides in immunized guinea pigs indicated that only the DSI2-mannopeptides elicited a delayed hypersensitivity reaction. Skin testing T. mentagrophytes 62-infected guinea pigs with the four purified DS-glycopeptides, as well as earlier fractions from the purification scheme, derived from T. mentagrophytes, T. rubrum, and M. canis, again indicated that only the DSI2-mannopeptides of the two Trichophyton species elicited a delayed hypersensitivity reaction. The number of infections or duration of infection had no effect on the size of the skin test response. DSI2-mannopeptides were non-cross-reactive between genera when tested in Trichophyton-immunized or -infected guinea pigs and Microsporum-immunized guinea pigs.
Encapsulation of Bacteroides species
Authors: Babb J L , Cummins C S
Published: January 2020

Capsules were detected by the India ink method in cultures of Bacteroides fragilis, B. vulgatus, B. thetaiotaomicron, and B. ovatus. No capsules were found in the five strains of B. distasonis examined.
Venezuelan Encephalitis Virus: In Vivo Induction of a Chromosomal Abnormality in Hamster Bone Marrow Cells
Authors: Pruslin Fred H. , Rodman Toby C.
Published: January 2020

This study reports the induction in vivo of aneuploidy in bone marrow cells of the Syrian hamster after short-term infection with Venezuelan encephalitis virus.
Heterogeneity of the rhamnomannans from one strain of the human pathogen Sporothrix schenckii determined by 13C nuclear magnetic resonance spectroscopy
Authors: Travassos L R , Mendonça-Previato L , Gorin P A
Published: January 2020

The synthesis of different rhamnomannans in a strain of Sporothrix schenckii (1099.12) was shown by use of 13C nuclear magnetic resonance spectroscopy. Fractionation of a polysaccharide preparation from cells grown at 25 degrees C provided a neutral monorhamnosyl rhamnomannan and an acidic rhamnomannan containing 4-O-substituted glucuronic acid units and also (1 leads to 2)-linked dirhamnosyl side chains.
Intestinal Enzyme Activities in Germfree, Conventional, and Gnotobiotic Rats Associated with Indigenous Microorganisms
Authors: Kawai Yasuo , Morotomi Masami
Published: January 2020

Various enzyme activities involved in the active transport system, glycolysis, and digestion were assayed in various parts of the gastrointestinal tracts of germfree, conventional, and gnotobiotic rats associated with indigenous bacteria. The activity levels of alkaline phosphatase, glucose 6-phosphatase, adenosine triphosphatase, and disaccharidases in the upper small intestine were highest in all parts of the gastrointestinal tracts of various kinds of gnotobiotic, conventional, and germfree rats. Alkaline phosphatase, glucose 6-phosphatase, and adenosine triphosphatase activities in the upper small intestine of germfree rats were, respectively, 2.3-, 2.9-, and 1.7-fold higher than those in conventional rats. Similar to the results of these enzymes, sucrase, maltase, trehalase, and lactase activities in the upper small intestine of germfree rats were, respectively, 1.6-, 1.5-, 2.3-, and 1.8-fold higher than those in conventional rats. In various gnotobiotic rats, enzyme activity levels were intermediate between those in germfree and conventional rats. These findings suggest that those enzymatic activities are strongly depressed by the association with the indigenous microorganisms in the epithelial mucosa of the upper small intestine of rats. The levels of pyruvate kinase, hexokinase, and lactate dehydrogenase activities were highest, respectively, in the stomach, cecum, and the upper small intestine and cecum in all parts of the gastrointestinal tracts in various kinds of gnotobiotic, conventional, and germfree rats. It was also shown that six kinds of gastrointestinal bacteria, including lactobacilli, significantly depressed the enzyme activity levels to levels between those of the germfree and conventional rats in the upper small intestine of gnotobiotic rats.
Role of Exotoxin and Protease as Possible Virulence Factors in Experimental Infections with
Pseudomonas aeruginosa
Authors: Snell Kathleen , Holder Ian A. , Leppla Stephen A. , Saelinger Catharine B.
Published: January 2020

Evidence is presented which suggests that both the proteases and the exotoxin produced by
Pseudomonas aeruginosa
multiplying in situ in a burned mouse model are virulence factors. A 50% decrease in functional elongation factor 2 (EF-2) was seen 16 h postinfection in the liver of mice infected with the toxigenic, protease-producing
P. aeruginosa
strain M-2; at the time of death EF-2 was depleted by 80%. This correlates with a reduction in the level of protein synthesis in the liver of infected animals. Treatment with specific antitoxin extended the mean time to death and blocked depletion of EF-2. Administration of gentamicin 24 h after infection caused rapid clearance of bacteria and extended the mean time to death, but all animals treated with either antitoxin or gentamicin eventually died. In contrast, treatment with both antitoxin and gentamicin provided virtually complete protection. Infection of mice with
P. aeruginosa
WR5 (protease-producing, nontoxigenic) or with
P. aeruginosa
PA103 (toxigenic, slow protease producer) required several logs more bacteria and did not result in the same extensive depletion in EF-2 content. When challenge with PA103 was supplemented by injection of purified
Pseudomonas
protease, the mean time to death was shortened and significant reduction in liver EF-2 was observed. It is suggested that both toxin and proteases are required for the full expression of virulence in
Pseudomonas
infections.
Interaction of lipopolysaccharides and lipid A with complement in rats and its relation to endotoxicity
Authors: Freudenberg M A , Galanos C
Published: January 2020

Uniform salt forms of endotoxic lipopolysaccharides (LPS) and free lipid A showing distinct differences in their anticomplementary activity, as well as a nontoxic LPS, are used in a new approach of studying the role of complement in endotoxin shock. The use of these defined LPS forms led to the identification of two timely, distinct depressions in complement hemolytic activity after administration of endotoxin in rats. An early depression occurred within 10 min after injection, and a late one developed more gradually, with lowest values at 6 to 9 h. The early depression represents a direct interaction of LPS with complement. It was obtained by toxic and nontoxic preparations that exhibit a high molecular weight and anticomplementary activity in vitro. The early depression was not related to the toxic properties of the LPS. The late depression was obtained only with endotoxically active LPS in lethal and 100-fold-lower concentrations, regardless of their molecular weight and of their in vitro anticomplementary activity.