bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Peritoneal Macrophages from Germfree and Conventional Mice
Authors: Mørland Berit , Smievoll Alf I. , Midtvedt Tore
Published: January 2020

Morphology, lysosomal enzyme activities, and phagocytosis via immunological receptors were tested in peritoneal macrophages from germfree and conventional mice. Nonstimulated macrophages from germfree mice showed less spreading and were more easily detached when seeded on glass than conventional macrophages. The activities of the lysosomal acid phosphatase and cathepsin D were similar in the two cell groups, whereas β-glucuronidase showed higher activity in macrophages from germfree mice. F
c
receptor-mediated phagocytosis of opsonized sheep erythrocytes was equally effective in germfree and conventional macrophages, and both cell types attached but did not internalize erythrocytes via the C
3
b receptor. Intraperitoneal injections of mineral oil caused a significantly higher influx of macrophages in conventional mice than in germfree mice, whereas the influx of polymorphonuclear cells was enhanced in both animals. Stimulation in vivo with oil or
Escherichia coli
endotoxin increased cell size, spreading ability, membrane ruffling, and lysosomal enzyme activities in macrophages from both conventional and germfree mice. The Fc-mediated phagocytosis was not influenced by stimulation, whereas the capacity to internalize via C
3
b receptor was triggered in macrophages from conventional mice, but not in corresponding cells from germfree mice. Similar results were obtained after stimulation with endotoxin in vitro. Culture in fetal calf serum for 72 h caused intracellular rises in all three enzyme activities tested in macrophages from conventional mice, whereas only the activity of acid phosphatase was increased in macrophages from germfree mice. Stimulation with zymosan in vitro caused selective release of lysosomal enzyme activity in macrophages from both animal groups. We conclude that peritoneal macrophages from germfree mice share several properties with cells from conventional mice, however, unstimulated β-glucuronidase activity was increased, whereas spreading on glass, chemotactic response, in vitro induction of lysosomal enzymes, and the capacity to internalize via the C
3
b receptor after stimulation were reduced or absent.
Herpetic keratitis in athymic (nude) mice
Authors: Metcalf J F , Hamilton D S , Reichert R W
Published: January 2020

The inflammatory response to herpes simplex virus infection of the cornea was studied in athymic nude (nu/nu) and heterozygote (nu/+) BALB/c mice. Although athymic mice were highly susceptible to HSV infection and died 13 to 17 days after corneal inoculation, they failed to develop necrotizing keratitis of the cornea. Heterozygote mice survived the initial virual infection, but many of these mice developed necrotizing keratitis and permanent corneal scarring. Light and electron microscopy showed numerous inflammatory cells (polymorphonuclear leukocytes and lymphocytes) in the corneas of heterozygote mice, but not in the athymic mice. These studies suggest that the immune system plays a dual role in herpes simplex virus infection of the cornea: protection against dissemination of the virus and immunopathogenesis of necrotizing keratitis in the cornea.
Biology of Mouse Thymic Virus, a Herpesvirus of Mice, and the Antigenic Relationship to Mouse Cytomegalovirus
Authors: Cross S. S. , Parker J. C. , Rowe W. P. , Robbins M. L.
Published: January 2020

Mouse thymic virus (TA) is a herpesvirus which produces extensive necrosis of the thymus of newborn mice 7 to 14 days after infection. Infectious virus can be recovered from the thymus for only 10 days after infection, with highest titers occurring between days 5 and 7. In mice 5 days old or less, TA infects thymus cells and produces massive necrosis. TA also infects the salivary glands and persists as a chronic infection. Newborn mice infected with TA have no detectable humoral immune response. Infected adult mice respond, and humoral antibody is detected 7 days after infection. Titers are maintained for months thereafter. Regardless of the age of the mice inoculated with TA, persistent infection was established in the salivary glands, but no evidence for thymus involvement was observed when adults were infected. TA does not cross-react serologically by immunofluorescent, complement fixation, or virus neutralization tests with mouse cytomegalovirus; however, interestingly, the epidemiology of the two herpesviruses are similar. Both mouse cytomegalovirus and TA were isolated from the same animals in populations of laboratory and wild mice. Evidence of infection with mouse cytomegalovirus and TA were most apparent by virus isolations, since humoral antibody responses are rarely observed. All strains of mice tested were susceptible to TA infection. However, in some strains maximum necrosis occurred at 7 days, compared with 10 to 14 days for other strains. The difference in age susceptibility and the target tissue of thymus in newborn mice suggests that TA is a model herpesvirus for studying the effects of viral infections on humoral and cell-mediated immunological functions.
Inhibition of adsorption of Streptococcus mutans strains to saliva-treated hydroxyapatite by galactose and certain amines
Authors: Gibbons R J , Qureshi J V
Published: January 2020

Adsorption of all of eight strains of Streptococcus mutans to saliva-treated hydroxyapatite (S-HA) surfaces was inhibited by galactose and melibiose, but not by other neutral sugars tested. This observation supports the hypothesis that lectin-like components participate in the attachment of these streptococci to salivary glycoproteins on saliva-treated hydroxyapatite surfaces. Adsorption of all strains was also inhibited by iodoacetate and spermine; other amines tested reduced adsorption of some strains, but not others.
Genetic control of the murine corneal response to Pseudomonas aeruginosa
Authors: Berk R S , Leon M A , Hazlett L D
Published: January 2020

Inbred mouse strains differ in susceptibility to intracorneal challenge with Pseudomonas aeruginosa. Genetic studies indicate that resistance to corneal infection is dominant over susceptibility and is controlled by autosomal genes, at least one of which is located outside of the H-2 locus. On the basis of genetic complementation studies, the susceptible strains BALB/c and C57BL/6 each bear one resistance gene, since the F1 hybrid (BALB/c X C57BL/6) was uniformly resistant to infection.
Quantitation of the Third Component of Human Complement Attached to the Surface of Opsonized Bacteria: Opsonin-Deficient Sera and Phagocytosis-Resistant Strains
Authors: Verbrugh Henri A. , van Dijk Willemien C. , van Erne Marijke E. , Peters Roel , Peterson Phillip K. , Verhoef Jan
Published: January 2020

The role of the third component of human complement (C3) in the opsonization of bacteria in nonimmune human sera was evaluated. The amount of C3 that becomes attached to the surface of bacteria upon incubation in serum was measured in a quantitative fluorescent immunoassay using fluorescein-conjugated monospecific antiserum to human C3. The intensity of the fluorescence from opsonized bacteria was found to be directly proportional to the absolute amount of C3 fixed, and this enabled the detection of as few as 300 molecules of bound C3 per bacterium. In normal serum the rate of C3 fixation was closely correlated with an increase in opsonization of the bacteria for human PMNs. Both C3 fixation and opsonization were maximal after 15 min of incubation. C3 fixation was also observed, albeit at a significantly slower rate, in human serum with a nonfunctional classical pathway but an intact alternative complement pathway and in serum deficient in immunoglobulins. Again, the kinetics of C3 fixation correlated with bacterial opsonization. Using a total of 21 strains of several bacterial species, including
Staphylococcus aureus
and
Escherichia coli
, encapsulation of bacteria was found to interfere with the process of C3 fixation in normal human serum, rendering these organisms resistant to subsequent phagocytosis by human polymorphonuclear leukocytes.
Chemical Analysis of Changes in Membrane Composition During Growth of
Streptococcus pyogenes
Authors: van de Rijn Ivo , Kessler Robert E.
Published: January 2020

Changes in the structural components of the
Streptococcus pyogenes
membrane between exponential and early stationary phases of growth are reported. The overall protein composition ranged from 70 to 73% of the dry weight of the membranes, irrespective of the phase of growth from which they were isolated. Amino acid analyses of membranes isolated from streptococci in either the exponential or stationary phase of growth demonstrated that two amino acids, cysteine and tryptophan, were absent. Further analysis of the membrane proteins by sodium dodecyl sulfate-polyacrylamide gradient gel electrophoresis demonstrated that there were proteins unique to a particular phase of growth as well as differences in the amount of specific proteins from the various growth phases. In addition, membranes isolated from exponential-phase cultures contained a higher percentage of peripheral protein than did stationary-phase membranes. There also appeared to be an increase in the amount of outer surface proteins during this growth phase. The phosphorus content of the membranes increased during the stationary phase of growth, whereas the sugar composition remained constant. The only sugar found under various conditions of growth in any of the strains was glucose. Total fatty acid content and the mole percent composition of various fatty acids did not change in the different phases of growth. However, the mole percent composition of fatty acids in the membranes of various group A streptococci did differ between strains. Therefore, these results provide evidence that the composition of membranes of
S. pyogenes
does not remain constant throughout the growth phases of the culture.
Disproportionate elevation of the immunoglobulin G1 concentration in cerebrospinal fluids of patients with multiple sclerosis
Authors: Kaschka W P , Theilkaes L , Eickhoff K , Skvaril F
Published: January 2020

We determined immunoglobulin G (IgG) subclass concentrations and studied their distributions in the cerebrospinal fluids of patients suffering from multiple sclerosis, other inflammatory neurological diseases, and non-inflammatory diseases of the nervous system in comparison with a control group. In addition, the four subclass concentrations were measured in serum specimens of the multiple sclerosis and control groups. These data were correlated with the extent of local IgG synthesis in the subarachnoid spaces of the patients belonging to the different groups. We found a selective elevation of the IgG1 subclass in the cerebrospinal fluids of multiple sclerosis patients, and there was only a very small overlap of the IgG1 ranges of the multiple sclerosis and control groups. No major differences were detected between the IgG subclass distributions in different courses of multiple sclerosis nor between multiple sclerosis and control sera. The group with non-inflammatory diseases showed a uniform elevation of all four subclasses and a greater overlap with the normal range. This latter feature was combined with an elevated IgG1 concentration in the group with other inflammatory diseases. It is concluded that locally synthesized IgG in the cerebrospinal fluids of multiple sclerosis patients consists mainly of IgG1.
Evaluation of the Immune Response Directed Against the
Salmonella
Antigenic Factors O4,5 and O9
Authors: Lyman M. B. , Stocker B. A. D. , Roantree R. J.
Published: January 2020

A pair of O4,5,12 and O9,12
his
+
sister transductants derived from a virulent
Salmonella typhimurium
parent were used as intraperitoneal and oral challenge strains to determine whether immunity directed against the O9 and O4,5 antigenic components could be detected after immunization with heat-killed vaccines containing one or the other of these antigenic components. Challenge with a mixture (ca. 1:1) of the two strains and culturing of livers and spleens at intervals indicated that the O4,5,12 strain multiplied to a greater extent than the O9,12 strain after both oral and intraperitoneal challenge of CF1 and C57BL/6J control mice. Immunization with O4,5,12 or O9,12 vaccine resulted in diminished bacterial counts from the livers and spleens for the homologous strain but had little effect on the heterologous strain. The diminution of the homologous strain was more evident after intraperitoneal challenge but was clearly demonstrable after oral challenge, particularly in the C57BL/6J mice. Of several live vaccines tested, an FOR
S. typhimurium
(O4,5,12) strain phenotypically smooth but avirulent seemed the most promising, suppressing the multiplication of both members of the challenge pair. After oral challenge suppression of the O4,5,12 strain was greater. These results indicate that the specific immune response directed against either the O4,5 (O-acetyl abequose) or the O9 (tyvelose) antigen is a measurable component of the overall response after both intraperitoneal and oral challenge.
Neutrophil Chemotaxis Dysfunction in Human Periodontitis
Authors: Van Dyke T. E. , Horoszewicz H. U. , Cianciola L. J. , Genco R. J.
Published: January 2020

Polymorphonuclear leukocyte (PMNL) chemotaxis studies of 32 patients with localized juvenile periodontitis (periodontosis or LJP), 10 adult patients with a history of LJP (post-LJP), 8 patients with generalized juvenile periodontitis (GJP), and 23 adults with moderate to severe periodontitis were performed: (i) to determine the prevalence of a PMNL chemotaxis defect in a large group of LJP patients; (ii) to study PMNL chemotaxis in patients with other forms of severe periodontal disease; and (iii) to determine if the PMNL chemotaxis defect seen in LJP patients is a cell-associated defect or is mediated by humoral factors. The effect of periodontal treatment on PMNL chemotaxis was studied in nine LJP patients. The chemotactic response was measured with the Boyden chamber procedure, and patient's peripheral PMNL were compared with those of control subjects, using endotoxin-activated serum, bacterial factor,
N
-formylmethionyl-leucylphenylalanine, and leukocyte-derived chemotactic factor as the standard chemoattractants. Based upon statistical analysis of chemotaxis assays, most carried out on at least two and often three or more separate occasions, 26 of 32 LJP patients, 7 of 10 post-LJP patients, and 5 of 8 GJP patients exhibited cellular defects of chemotaxis, whereas only 2 of 23 of the patients with adult periodontitis exhibited depressed chemotaxis. Elevated PMNL chemotaxis was occasionally found in subjects with juvenile periodontitis (2 of 32 with LJP and two of eight with GJP); however, it was found in a significant number (10 of 23) of patients with adult periodontitis. In eight of nine LJP patients, depressed PMNL chemotaxis was observed before and after periodontal therapy. The results indicate that the PMNL chemotaxis defect observed in juvenile periodontitis is due to a cell-associated defect of long duration. These studies suggest that the PMNL plays a major protective role against periodontal infection and that the cellular chemotactic defects and may predispose subjects to LJP.
Experimental Murine Candidiasis: Cell-Mediated Immunity After Cutaneous Challenge
Authors: Moser Stephen A. , Domer Judith E. , Mather Frances J.
Published: January 2020

Male CBA/J mice, sensitized by cutaneous inoculation with viable
Candida albicans
blastospores, were used to study in vivo and in vitro cellular immune responses. Three antigens of
C. albicans
, viz., a cell wall glycoprotein (GP), a membrane extract (ppt-HEX), and soluble cytoplasmic substances (SCS), were used in vitro in a lymphocyte stimulation assay, whereas the GP and ppt-HEX were used in vivo to detect delayed hypersensitivity by the footpad assay. Delayed hypersensitivity to GP and ppt-HEX was transferred from sensitized donors to naive recipients with peritoneal exudate cells and not with serum. Moreover, the transfer of the reactivity to ppt-HEX was abrogated by the prior treatment of the transfer suspension with anti-theta 1.2 serum and complement. The in vitro lymphocyte response to GP and ppt-HEX correlated qualitatively with the in vivo responses. SCS, a preparation shown to be ineffective in vivo previously, did stimulate lymphocytes from sensitized animals in vitro. The in vitro response to
Candida
antigens, as well as phytohemagglutinin, was abolished by treatment of the lymphocyte suspension with anti-thymocyte 1.2 serum before assay, whereas anti-immunoglobulin serum had less effect on these responses. The in vivo and in vitro reactivity to the
Candida
antigens, therefore, was dependent upon viable T-lymphocytes. Preliminary specificity studies were carried out in the lymphocyte stimulation assay, using lymphocytes from mice infected with
C. albicans
tested against ppt-HEX preparations extracted from two other species of
Candida, C. tropicalis
and
C. guillermondii
, and from two other pathogenic yeast forms,
Histoplasma capsulatum
and
Blastomyces dermatitidis
. Significant cross-reactivity was observed with
C. tropicalis
only, a species which is known to be serologically related to
C. albicans
.
Effect of prostaglandins and cyclic adenosine 3',5'-monophosphate modulators on herpes simplex virus growth and interferon response in human cells
Authors: Trofatter K F , Daniels C A
Published: January 2020

Mechanisms whereby prostaglandins and other cyclic adenosine 3',5'-monophosphate (cAMP) modulators might enhance the growth of herpes simplex virus (HSV) in human skin fibroblasts were explored. Prostaglandins A1, B1, E1, E2, and F2 alpha, as well as isoproterenol, imidazole, carbamylcholine, and dibutyryl cAMP had no effect on HSV growth. On the other hand, the phosphodiesterase inhibitors 1-methyl-3-isobutylxanthine and theophylline delayed the growth, suppressed the cell-to-cell spread, but inhibited neither the adsorption nor the penetration of the virus. Although none of the cAMP-elevating reagents directly enhanced HSV growth, they were found to inhibit dose dependently the antiviral action of both type I and HSV antigen-induced human interferon preparations. Furthermore, these reagents suppressed the production of HSV antigen-induced interferon by immune human mononuclear leukocytes. These data support the hypothesis that prostaglandin elaboration in vivo could contribute to exacerbations of HSV infections by compromising the host's interferon defense system.
Effect of T-cell deficiency on the chronicity of arthritis induced in mice by Mycoplasma pulmonis
Authors: Keystone E C , Taylor-Robinson D , Osborn M F , Ling L , Pope C , Fornasier V
Published: January 2020

Mycoplasma pulmonis inoculated parenterally into athymic nude mice congenitally deficient in T cells caused a chronic arthritis of significantly greater magnitude than in immunologically normal mice. During the chronic phase of arthritis, M. pulmonis organisms were isolated from the joints and spleens of athymic nude mice more frequently and in larger numbers than from immunologically normal mice. The results support the concept that impaired T-cell function predisposes the mice to a severe degree of chronic arthritis as a result of their failure to eliminate the causative organisms.
Production of K99 antigen by enterotoxigenic Escherichia coli strains of antigen groups o8, o9, o20, and o101 grown at different conditions
Authors: de Graaf F K , Wientjes F B , Klaasen-Boor P
Published: January 2020

The production of the K99 antigen by enterotoxigenic Escherichia coli strains with various O antigens was investigated by means of slide agglutination tests, enzyme-linked immunosorbent assays, and hydrophobic interaction chromatography. The extent of K99 production appeared to be dependent on the nutrient medium, as well as on the incubation temperature. Minimal salt medium with glucose and semisynthetic Minca medium were the most suitable for K99 production. In complex media the production of K99 antigen was strongly reduced. Optimal amounts of K99 antigen were produced at 37 degrees C. At 30 degrees C, weak production of K99 antigen was detected by hydrophobic interaction chromatography of enzyme-linked immunosorbent assay. Slide agglutination tests were negative with cultures grown below 32 degrees C. The production of K99 antigen appeared to be related to the O antigen carried by the host strain, but it seemed to be independent of the absence or the presence of various K polysaccharide antigens. Under all conditions used, strains with antigen O101 produced about 10 times more K99 antigen than did strains with antigen O8, O9, or O20. Transfer of the K99 plasmid from wild-type strains of different O antigens to E. coliK-12 C600 confirmed that phenotypic expression of the K99 antigen is most probably related to the cell wall composition of the host.
Characterization of tufted streptococci isolated from the "corn cob" configuration of human dental plaque
Authors: Mouton C , Reynolds H S , Genco R J
Published: January 2020

Streptococci isolated from "corn cob" configurations of human dental plaque possess a polar fibrillar tuft extending 100 to 150 nm from one pole of the cell. The two strains studied were physiologically related to the Streptococcus sanguis-Streptococcus mitior group and were most similar to Streptococcus mitis ATCC 903. The corn cob streptococci were serologically related to S. sanguis serotype 1. The polar tuft contained at least two antigenically distinct components, one serologically related to the glycerol phosphate backbone of teichoic acid. The other was an electrophoretically slow-moving antigen similar to a component of S. mitis ATCC 903. It is suggested that the corn cob streptococci in vivo adhere to Bacterionema matruchotii by means of the polar tuft.
Rate of clearance of virulent Treponema pallidum (Nichols) from the blood stream of normal, Mycobacterium bovis BCG-treated, and immune syphilitic rabbits
Authors: Graves S
Published: January 2020

The rate of clearance of virulent Treponema pallidum (Nichols) from the blood stream of normal rabbits and rabbits previously treated with Mycobacterium bovis BCG was similar, there being treponemes still circulating 8 h after intravenous inoculation. In contrast, immune syphilitic rabbits cleared the virulent treponemes within 1 to 2 hours. Rabbits with passive humoral immunity to T. pallidum (after the transfer of 70 ml of immune serum) showed a similar clearance rate to that of the immune rabbits. Rabbits previously treated with BCG and with passive humoral immunity did not show a synergistic enhanced clearance rate, it being similar to that of immune rabbits.
Immunization of mice with Trypanosoma cruzi polyribosomes
Authors: Leon L L , Leon W , Chaves L , Costa S C , Cruz M Q , Brascher H M , Lima A O
Published: January 2020

Studies were carried out with a polyribosomal fraction isolated from Trypanosoma cruzi Y epimastigotes, with the intention to determine both its immunogenic activity and the degree of protection it could induce against experimental T. cruzi infection. This fraction was assayed in four groups of mice by using different schedules of vaccination and varying the dose, intervals, and route of administration. Seven days after the last dose, the animals were sacrificed for immunological studies or subjected to challenge with T. cruzi trypomastigotes. The results obtained in all schedules showed that our polyribosomal fraction only induced a weak antibody response, but was capable of evoking an expressive cellular response. It was also shown that this fraction has the capacity of inducing a high degree of protection against T. cruzi infection, as determined by the decrease of parasitemia and the prolonged survival time of immunized animals.
Exological relationships of bacteria involved in a simple, mixed anaerobic infection
Authors: Mayrand D , McBride B C
Published: January 2020

Infectivity of Bacteroides asaccharolyticus (formerly B. melaninogenicus subsp. asaccharolyticus; see S. M. Finegold and E. M. Barnes, Int. J. Syst. Bacteriol. 27:388--391, 1977) was dependent on the presence of a second organism. An infective consortium consisting of B. asaccharolyticus and Klebsiella pneumoniae was defined. Neither organism was infective alone, but the Klebsiella could be replaced by organisms of a number of different genera. The nature of the infection appeared to be determined by the length of the lag period preceding the initiation of growth of B. asaccharolyticus. A rapid onset of growth led to the severe spreading form of the disease, whereas a slow initiation of growth resulted in the formation of a localized, self-limiting abscess. B. asaccharolyticus depends on the second or "helper" organism to produce a required growth factor which is not present at the inoculation site. The growth factor was shown to be succinate which was able to replace the hemin requirement. The dependency on succinate produced by K. pneumoniae was demonstrated in agar medium, in liquid culture, and in the infectivity assay. Any organism which produced succinate was able to stimulate growth of B. asaccharolyticus on agar medium and could replace K. pneumoniae as a member of the infectious consortium. The need for the second organism could be eliminated by inoculating B. asaccharolyticus together with agar-immobilized succinate or hemin.
Proteolytic action of Legionella pneumophila on human serum proteins
Authors: Müller H E
Published: January 2020

Proteolysis by four strains of Legionella pneumophila, the etiological agent of Legionnaires disease, was studied by the method of immunoelectrophoresis. Twenty-three human serum proteins were tested as substrates. Five proteins were degraded: alpha 1-acid glycoprotein, alpha 1-antichymotrypsin, beta-lipoprotein, beta 1E-globulin, and beta 2-glycoprotein-I. Moreover, the degradation of alpha 1-antichymotrypsin was demonstrated by investigation of an enzyme-blocking test. It is suggested that the proteolytic activity of L. pneumophila may bear some relationship to its pathogenic activity.
Effect of selenium and dimethyl dioctadecyl ammonium bromide on the vaccine-induced immunity of Swiss-Webster mice against malaria (Plasmodium berghei)
Authors: Desowitz R S , Barnwell J W
Published: January 2020

The results of the study described in this paper demonstrate that selenium, administered in drinking water, potentiates the protective effect of a killed Plasmodium berghei vaccine for Swiss-Webster mice. We also report that a vaccine consisting of P. berghei antigen combined with the adjuvant dimethyl dioctadecyl ammonium bromide conferred a significantly high level of protective immunity. An additive effect was shown in that the greatest degree of protection was afforded to the group of mice maintained on selenium and vaccinated with antigen-dimethyl dioctadecyl ammonium bromide. Almost all of the animals treated in this manner survived the challenging infection, the course of which was typically of a transitory parasitemia not exceeding 10% at the peak.
Depression of B-lymphocyte levels in the peripheral blood of cows with mastitis
Authors: Yang T J , Jantzen-Abo P A , Williams L F
Published: January 2020

The levels of B-lymphocytes in the peripheral blood of normal and mastitic cows were evaluated by fluorescent-antibody and erythrocyte-antibody-complement-rosetting techniques. Normal cows (N = 8) had 26.9 +/- 4.4% surface membrane immunoglobulin-positive lymphocytes, whereas mastitic cows (N = 6) had only 16.3 +/- 3.6% similar cells among lymphocyte preparations purified by the Ficoll-Paque density gradient separation and carbonyl iron phagocytosis methods. Studies on smiliar lymphocyte preparations by erythrocyte-antibody-complement-rosetting techniques showed that normal cows (N = 12) had 33.5 +/- 7.1% erythrocyte-antibody-complement-rosetting lymphocytes, whereas mastitic cows (N = 6) had 20.5 +/- 6.0% similar cells.
Isolation of deoxyribonucleic acid from Mycobacterium avium by rapid nitrogen decompression
Authors: Yandell P M , McCarthy C
Published: January 2020

Deoxyribonucleic acid (DNA) of high molecular weight could be isolated from cells of Mycobacterium avium if the cells were exposed to nitrogen gas at 1,500 lb/in2 for 30 min and then brought to atmospheric pressure by rapid decompression. DNA isolated from the cells had a molecular weight of 4.8 x 10(6) to 17.4 x 10(6). DNA was also released into the fluid in which the cells were suspended during nitrogen decompression. One-half of this DNA, representing 3% of the total DNA phosphorus in the cells had a uniform molecular weight of 4.2 x 10(6). This DNA was linear in conformation, and removal of associated carbohydrates did not change its sedimentation rate. The biological function or significance of the 4-megadalton DNA was not determined.
Mucin model for group B type III streptococcal infection in mice
Authors: Fleming D O
Published: January 2020

An experimental murine infection was established by the intraperitoneal injection of a log-phase culture of a laboratory reference strain of Streptococcus agalactiae, Lancefield group B, type III (strain SS620), suspended in sterile hog gastric mucin. The enhancement of streptococcal virulence was measured by a significantly increased mortality in outbred ICR Swiss mice. An inbred C57BL6 strain of mice was resistant to the mucin-bacterial combination. Mucin, treated with Desferal to chelate the iron, did not lose the capacity to enhance the virulence of group B, type III streptococci in ICR Swiss mice. Iron-dextran was not a suitable substitute for mucin and failed to enhance the virulence of group B, type III streptococci. The results of these studies indicate that iron is not the resistance-lowering factor in this group B, type III streptococci-mucin model.
Genetic mapping in phage group 2 Staphylococcus aureus
Authors: Martin S M , Shoham S C , Alsup M , Rogolsky M
Published: January 2020

Two regimens for transformation have been devised for the phage group 2 strains UT0002-19 and UT0017 of Staphylococcus aureus. Strain UT0002-19 produces exfoliative toxin, which is responsible for the clinical manifestations of the staphylococcal scalded skin syndrome, whereas strain UT0017 does not produce exfoliative toxin. A large pool of antibiotic-resistant and auxotrophic mutants from strains UT0002-19 and UT0017 were isolated by using (i) antibiotic gradient plates, (ii) trimethoprim selection, and (iii) nitrosoguanidine mutagenesis, which sometimes was coupled by enrichment with penicillin or methicillin. Transformation frequencies of genetic markers in mutant strains ranged from 10(-6) to 10(-8). Three genetic linkage groups were identified on the strain UT0017 chromosome. The first linkage group was thy-4-lys-5-trp-21-thr-4, the second was pyr-26-nov-9-his-3, and the third consisted of ilv-9 and pen-1, a genetic determinant for beta-lactamase synthesis. Two linkage groups were detected on the strain UT0002-19 CHROMOSOMe. The first was defined as thy-1-lys-5-trp-3-thr-4-ala-8, whereas the second consisted of nov-9 and his-3 markers. A chromosomal locus that controlled synthesis of exfoliative toxin could not be mapped.
Effect of immunosuppression on the development of experimental hematogenous Candida endophthalmitis
Authors: Henderson D K , Hockey L J , Vukalcic L J , Edwards J E
Published: January 2020

The induction of neutropenia and immunosuppression by the administration of nitrogen mustard (HN2) decreased the frequency and altered the morphology of clinically detectable hematogenous Candida endophthalmitis in the rabbit model of disseminated candidiasis. Whereas 95% of eyes in rabbits infected with Candida albicans without pretreatment with HN2 developed typical lesions of hematogenous Candida endophthalmitis, only 6.2% of eyes in rabbits that had been given 3.0 mg of HN2 per kg developed clinically detectable endophthalmitis. Lesions that developed in the severely immunocompromised and neutropenic rabbits were small and atypical in appearance. From these data, we conclude that ophthalmoscopic examination may not be a sensitive diagnostic modality for disseminated candidiasis in severely immunocompromised, neutropenic patients.
Influence of serum concentration on opsonization by the classical and alternative complement pathways
Authors: Tofte R W , Peterson P K , Kim Y , Quie P G
Published: January 2020

In this investigation of bacterial opsonization by the serum complement system, the importance of using various serum concentrations and of performing kinetic studies is demonstrated.
Chemotaxigenesis by encapsulated Staphylococcus aureus M
Authors: Schmeling D J , Peterson P K , Barr I M , Kim Y , Quie P G
Published: January 2020

Although encapsulated Staphylococcus aureus M is not opsonized by normal human serum, as a chemotaxigen this organism behaved similarly to an unencapsulated variant strain. For optimal chemotaxigenesis, an intact classical complement pathway was required, and C5a appeared to be the major chemotaxin.
Genetic resistance to Trypanosoma congolense infections in mice
Authors: Whitelaw D D , Macaskill J A , Holmes P H , Jennings F W , Urquhart G M
Published: January 2020

The mechanisms of genetic resistance or "trypanotolerance" to infection with Trypanosoma congolense were investigated in two strains of mice. One strain C57BL, is outstandingly resistant to most stabilates of T. congolense and can survive for over 80 days, whereas CFLP, in common with most other strains, generally succumbs in less than 20 days. Evaluation of several pathophysiological and immunological parameters showed that after infection both strains initially developed similar levels of parasitemia, anemia, biochemical derangement, and immunosuppression. The most outstanding difference was after day 8 postinfection, when the susceptible strain (CFLP) sustained high levels of parasitemia (10(9) trypanosomes per ml) until death 2 to 4 days later, whereas the resistant strain (C57BL) showed a marked decrease to less than 10(6) trypanosomes per ml by day 10 postinfection. Clear evidence that this was associated with the presence of trypanocidal antibody in the resistant mice was provided by the results of an infectivity neutralization test on serum collected from each strain at 10 days postinfection. Chronically infected C57BL mice showed declining waves of parasitemia and a slow restoration of most hematological and biochemical indexes to near normal levels by 80 days postinfection, although at this stage they remained immunosuppressed.
Mechanisms of immunity in typhus infection: analysis of immunity to Rickettsia mooseri infection of guinea pigs
Authors: Murphy J R , Wisseman C L , Fiset P
Published: January 2020

To study the mechanisms of immunity to Rickettsia mooseri (R. typhi) infection, sera and splenic cells collected from nonimmune and immune guinea pigs were inoculated separately into syngeneic nonimmune recipients which were subsequently challenged intradermally. Protection was measured by comparing the course of the challenge infections of recipients with infections initiated with the same rickettsial inocula in nonimmune animals. Recipients of splenic cells collected 21 days after donor infection were protected from lesion development at sites of intradermal challenge and showed fewer rickettsiae in their kidneys. Cells obtained from nonimmune donors did not protect against either skin lesion development at sites of challenge or kidney infection. Antibody-containing sera collected 21 days after donor infection, but not normal sera, reduced levels of kidney infection, but immune sera did not protect against the development of lesions at sites of intradermal challenge. It was concluded that both immune sera and immune splenic cells possess capacities to effect a partial control of the systemic phase of R. mooseri infection in guinea pigs, but that immune splenic cells possess a capacity not shared by immune sera, i.e., the capacity to protect from infection at local sites of intradermal inoculation.
Biological activities of fragments derived from Bordetella pertussis endotoxin: isolation of a nontoxic, Shwartzman-negative lipid A possessing high adjuvant properties
Authors: Ayme G , Caroff M , Chaby R , Haeffner-Cavaillon N , Le Dur A , Moreau M , Muset M , Mynard M C , Roumiantzeff M , Schulz D , Szabó L
Published: January 2020

Endotoxin from fresly sedimented Bordetella pertussis cells, isolated by the phenol/water procedure when submitted to kinetically controlled, mild acidic hydrolysis released a polysaccharide (polysaccharide 1), a complex lipid (lipid X), and a glycolipid. When treated with somewhat stronger acid, the glycolipid yielded a second polysaccharide (polysaccharide 2) and another complex lipid (lipid A). The intact pertussis endotoxin had all the usual properties of endotoxins extracted from enteric bacteria. Lipid X and the intermediary glycolipid retained all the endotoxic properties of the unfractionated endotoxin. In lipid A, pyrogenicity was reduced to a very low level and toxicity and Shwartzman reactivity were absent; however, this fraction retained most of the endotoxin's antiviral activity, and its adjuvant power was considerably higher than that of the intact endotoxin. Lipid A elicited nonspecific resistance against challenge with certain bacteria, but not against others.
Hereditary Characteristic that Varies Among Isolates of
Mycobacterium leprae
Authors: Shepard Charles C. , McRae Dorothy H.
Published: January 2020

Isolates of
Mycobacterium leprae
in mouse foot pads were found to differ in two related properties, the average rate of growth between inoculation and harvest (
G
) and the number of bacilli in the harvest (
H
). For “fast” strains the median values for
G
were less than 25 days per generation, and the median values for
H
were above 10
6.1
. For “slow” strains the median values for
G
were above 30, and the median values for
H
were below 10
5.6
. The
G
and
H
values for the 59 isolates for which data were available formed a continuous spectrum between the two extremes; there was no correlation with dapsone resistance. The fastness characteristic was stable; it did not change on passage in mice and was in agreement when more than one isolate had been made from the same patient. No important differences were apparent according to geographic origin of the infection of the patient. Histological studies showed that fast strains grew to a higher level without inducing the infiltrate of lymphocytes and macrophages that appears at the end of the logarithmic phase of growth in mouse foot pads. Although fast strains often had higher ratios of solidly staining (and presumably viable) bacilli in the inoculum, the fast-slow difference was not accounted for by the solid ratio. Slow strains differed from fast by having longer times until harvest and by having fewer generations of growth, even when their frequently lower solid ratios were taken into account.
Interferon Production in Mixed Lymphocyte Cell Cultures
Authors: Gifford George E. , Tibor Agnes , Peavy Duane L.
Published: January 2020

Mixed lymphocyte cultures from mice with marked differences in major and minor histocompatibility antigens were found to produce an inhibitor of viral replication with properties of interferon. Cultures produced maximal amounts of interferon at approximately 72 to 96 hr, a time when maximal stimulation of deoxyribonucleic acid synthesis also occurred.
Clostridium perfringens
Type A Food Poisoning II. Response of the Rabbit Ileum as an Indication of Enteropathogenicity of Strains of
Clostridium perfringens
in Human Beings
Authors: Strong Dorothy H. , Duncan Charles L. , Perna Giuseppe
Published: January 2020

The effect of feeding human beings individual strains of
Clostridium perfringens
or culture filtrates thereof was examined. The strains selected for challenge included both those which had previously been shown to produce fluid accumulation in the ligated ileum or overt diarrhea when injected into the nonligated ileum of the rabbit, or had produced both, and those which did not regularly produce these responses. Challenge doses prepared by allowing each strain to grow in beef stew for 3 hr at 46 C resulted in a 61% incidence of diarrhea when rabbit-positive cells were used. No diarrhea occurred among the subjects fed rabbit-negative strains prepared in a similar manner. The procedures employed in preparing the challenge dose appeared to influence the results obtained. When cell-free filtrates were fed, 4 of 15 persons consuming filtrates from rabbit-positive strains developed diarrhea. All subjects fed filtrates from rabbit-negative strains remained free from diarrhea. Serological tests were carried out to compare the identity of the strains of
C. perfringens
consumed by the subjects and those excreted in the feces. Heat resistance measured as
D
100
values varied greatly among the rabbit-positive strains.
Polyserositis Induced by
Escherichia coli
in Gnotobiotic Swine
Authors: Meyer R. C. , Saxena S. P. , Rhoades H. E.
Published: January 2020

The oral administration of an 18-hr broth culture of
Escherichia coli
06: isolated from a cat to 3-day-old gnotobiotic (germ-free) piglets resulted in bacteremia and polyserositis. Sixteen pigs, selected from four litters, were used in the study.
E. coli
of the same serotype employed was the only bacterial agent demonstrable and recovered from moribund and dead piglets. Attempts to recover virus or PPLO (mycoplasma) from these animals were unsuccessful. A polyserositis syndrome was not encountered among neonatal pigs in experiments with 14 other serotypes of
E. coli
; hence it was considered to be a syndrome closely associated with the infection caused by this particular strain of
E. coli.
Nonspecific Factors in Monkey Tissues and Serum Causing Inhibition of Plaque Formation and Hemagglutination by Dengue Viruses
Authors: Nash Donald R. , Halstead Scott B. , Stenhouse Andrew C. , McCue Carolyn
Published: January 2020

Normal monkey serum and the supernatant fluid from different triturated monkey tissues have been studied for the presence of nonspecific arbovirus hemagglutination and plaque forming inhibitors of dengue viruses types 1, 2, 3, and 4. Hemagglutination inhibition (HI) activity was present in most tissue specimens and demonstrated a significant gradient of effectiveness starting with, respectively, serum, spleen, adrenal, and lung having a high degree of activity, whereas skin, heart, muscle, brain, and liver demonstrated low HI titers. A slightly reversed gradient of effectiveness was obtained for the case of dengue virus inhibition of plaque formation with bile, liver, thymus, spleen, and adrenal giving high 50% plaque reduction titers and heart, muscle, serum, skin, and fat demonstrating little or no activity. Analysis by Sephadex G-200 chromatography and sucrose density gradient centrifugation suggests that HI and plaque formation inhibition are independent activities of normal serum or tissue constituents or both. Also, in addition to the physical methods of characterization, chemical treatment by absorption with kaolin or acetone extraction indicate both phenomena to be the result of the action of lipids or lipoproteins.
Virulence and Attenuation of Murine Cytomegalovirus
Authors: Osborn June E. , Walker Duard L.
Published: January 2020

Murine cytomegalovirus (MCMV) was rapidly and regularly attenuated by passage through mouse embryo cell culture. This attenuation was manifested by alteration of lethality for suckling mice and by a striking loss of capacity to multiply in liver and spleen of weanling mice. The attenuation was selective in that the passaged virus multiplied vigorously in other organs and established high titer infections in submaxillary glands and pancreas comparable to those seen with wild virus. Furthermore, attenuated virus no longer induced transient suppression of antibody and interferon responsiveness which was a regular feature of wild MCMV infection. Wild and attenuated MCMV shared the property of being poor immunogens. They induced anti-CMV complement-fixing or neutralizing antibody very slowly with barely detectable levels present at the end of the first 2 weeks of infection. The close antigenic relationship between wild and attenuated agents was demonstrated by nearly identical neutralization by a rabbit antiserum induced with wild MCMV. Furthermore, survivors of neonatal infection with attenuated virus were fully protected against subsequent challenge with potentially lethal doses of wild MCMV. Virulence could be rapidly restored by back passage in mice.
Radiation, Infection, and Macrophage Function IV. Effect of Radiation on the Proliferative Abilities of Mononuclear Phagocytes in Tuberculous Lesions of Rabbits
Authors: Chandrasekhar Saroj , Shima Kiyoshi , Dannenberg Arthur M. , Kambara Takeshi , Fabrikant Jacob I. , Roessler William G.
Published: January 2020

Rabbits were irradiated with 400 to 600 rads 2 to 3 days before they were infected with BCG or with virulent tubercle bacilli. Biopsies were periodically removed from the resulting lesions and incubated for 1 hr with
3
H-thymidine in vitro under hyperbaric oxygen. Twelve to 16 days after radiation there was a reduction in the percentage of mononuclear cells (macrophages and some lymphocytes) that had incorporated
3
H-thymidine in the lesions. At this time, the lesions of the irradiated group were smaller than those of controls. These results can be explained by the reduction in the number of new mononuclear cells that entered the lesions of the irradiated group and support the tenet that local mononuclear cell division occurs mainly in cells that have recently emigrated from the blood stream. An alternate, but less likely, explanation of these results would be that radiation caused the bone marrow to release a higher percentage of “defective” mononuclear cells that were unable to divide, i.e., incorporate
3
H-thymidine, in the lesions. The reduction produced by radiation in both local cell infiltration and local cell division would decrease the number of macrophages available to control the tuberculous infection in the host.
Nonencapsulated Variant of
Cryptococcus neoformans
I. Virulence Studies and Characterization of Soluble Polysaccharide
Authors: Kozel Thomas R. , Cazin John
Published: January 2020

A weakly virulent nonencapsulated variant of
Cryptococcus neoformans
is described. The chemical structure and antigenicity of the soluble polysaccharides produced by the variant strain and a typical virulent strain were compared. The soluble polysaccharides produced by both strains were composed of the same constituent monosaccharides; however, the virulent strain produced a polysaccharide having a greater uronic acid content and a larger molecular size than that of the variant strain. Soluble polysaccharides from the two strains are not closely related immunologically. Soluble polysaccharide obtained from the virulent strain did not affect persistence of the variant strain in mice.
Pathogenicity and Antigenicity of Clones from Strains of Marek's Disease Virus and the Herpesvirus of Turkeys
Authors: Purchase H. G. , Burmester B. R. , Cunningham C. H.
Published: January 2020

Virus was extracted by filtration from chicken embryo fibroblast cultures infected with the JM, high passage JM(JMHP), GA, and RPL39 strains of Marek's disease virus (MDV) and from the herpesvirus of turkeys (HVT) and purified by cloning. The plaques produced by clones of HVT, JMHP, and other MDV strains differed in morphology from one another. Clones of MDV varied greatly in pathogenicity for chickens, but JMHP and HVT were nonpathogenic. Two pathogenic clones of JM virus and a clone of JMHP virus lacked the A precipitin antigen present in all other clones tested. All clones had at least one B antigen in common. HVT and MDV clones with and without the A precipitin antigen could be distinguished from each other by the indirect fluorescent antibody test. Changes in virus-host cell relationships, loss of pathogenicity, and loss of the A antigens were independent events.