bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of a
Streptococcus salivarius
Cell Wall Component Mediating Coaggregation with
Veillonella alcalescens
VI
Authors: Weerkamp Anton H. , McBride Barry C.
Published: January 2020

Cell walls of
Streptococcus salivarius
HB aggregated
Veillonella alcalescens
V1, but cell walls of the mutant
S. salivarius
HB-V5 did not. We found no correlation between the presence of fimbriae on streptococcal walls and the ability to aggregate
Veillonella
strains. Treatment of the walls with lysozyme solubilized a fraction which possessed
Veillonella
-aggregating activity. Solubilized cell wall preparations of strain HB contained three major (glyco)proteins as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and at least four antigens as determined by immunoelectrophoresis with antiserum prepared against strain HB walls. A specific antiserum, which was obtained by adsorption of anti-HB serum on strain HB-V5 cells, contained monospecific antibody that reacted with the solubilized strain HB wall preparation. Similar fractions prepared from strain HB-V5 cell walls did not possess aggregating activity and lacked one protein band (protein I) after sodium dodecyl sulfate-polyacrylamide gel electrophoresis and one antigen (antigen b) after immunoelectrophoresis. The same antigen was absent when lysozyme-solubilized wall preparations of strain HB were reacted with anti-HB-V5 serum. Crossed-immunoisoelectric focusing indicated that this specific (glyco)protein and this antigen were identical and had an isoelectric point of 4.60. Protein I and antigen b were specifically adsorbed when solubilized strain HB cell walls were incubated with
V. alcalescens
V1 but were not adsorbed by nonaggregating
Veillonella parvula
ATCC 10790 cells. Culture supernatants of strain HB contained
V. alcalescens
V1-aggregating activity. Antigen b was present in the culture supernatant, but was not found in cultures of strain HB-V5. A total of 18
S. salivarius
isolates possessing the streptococcal group K antigen released aggregating activity and antigen b into the culture medium, but 11 strains which lacked the K-antigen did not.
Antibody to human adenovirus early antigens during acute adenovirus infections
Authors: Gerna G , Cattaneo E , Revello M G , Battaglia M , Achilli G
Published: January 2020

The antibody (Ab) response to human adenovirus (AV) early antigens (EA) in acute AV infections was studied by the immunoperoxidase antibody technique for determining virus-specific immunoglobulin G (IPA-IgG). AV-EA-Ab appeared about 5 days after the onset of clinical symptoms, reached a peak 15 to 30 days later, and declined in titer after a few months. The staining pattern in the IPA-IgG reaction was usually nuclear; however, in most primary infections sera obtained 2 to 3 weeks after the onset of infection also showed cytoplasmic staining. According to the recent deoxyribonucleic acid homology classification of human AV in five groups (A, B, C, D, and E), the EA-Ab response in primary human infections was found to be group specific for groups A to D, with consistent cross-reactions with group E. In AV type 4 (group E) infections, EA-Ab appeared to be directed against all groups, although at different titers. Comparable results were obtained using AV type-specific animal antisera. Thus, it was concluded that group E shares EA with all the other groups. Furthermore, in each individual with remote AV infections, the current infection elicited an anamnestic EA-Ab response to all AV groups responsible for previous infections. In diagnostic virology these findings can be applied to the rapid diagnosis of a current for recent) AV infection on a single serum sample and to the rapid group identification of clinical isolates by using type-specific animal antisera containing EA-Ab (one for each group) or sera from patients with primary AV infections.
Differentiation of Bacteroides nodosus biotypes and colony variants in relation to their virulence and immunoprotective properties in sheep
Authors: Skerman T M , Erasmuson S K , Every D
Published: January 2020

To obtain a wider definition of variation in the virulence of Bacteroides nodosus and in the protective potency of B. nodosus vaccines, we made a comparison of the in vitro characteristics of isolates from clinical infections of sheep and cattle and of certain colony variants observed previously. Three basic colony types were distinguished: papillate or beaded (B)-type colonies were produced by fresh isolates from advanced ovine foot rot; mucoid (M)-type colonies were formed by isolates from noninvasive B. nodosus infections of the interdigital skin of sheep and cattle, and also by cultures of some primary B-type colonies passaged nonselectively in vitro; and circular (C)-type colonies were formed by B. nodosus that eventually predominated in repeatedly passaged liquid subcultures. Each type could be maintained by selective agar subculturing; one strain was thus passaged 40 times as the B-type colony, at which point the organisms induced severe foot rot in experimentally infected sheep. Cultures of M-type colonies were uniformly less pathogenic and those of C-type colony organisms were avirulent. In vitro changes from prototype B-type colonies to M- and C-variants were nonreversible in these experiments, were accelerated in liquid cultures, and wee accompanied by a diminution in elastase activity of the organisms and in their immunoprotective properties against homologous challenge. Strains differed in their stability to these changes; therefore the choice of an appropriate strain and colony type may be an important consideration in studies of B. nodosus virulence and in the development of effective vaccines.
Cytomegalovirus-induced mononucleosis in guinea pigs
Authors: Griffith B P , Lucia H L , Bia F J , Hsiung G D
Published: January 2020

The effects of cytomegalovirus (CMV) infection on hematopoietic and lymphoid tissues were studied in guinea pigs. Blood parameters, histopathology, and virus distribution in the bone marrow, spleen, lymph nodes, and thymus were assessed during primary nonlethal acute and chronic guinea pig CMV infection. Transient hematological changes comparable to those seen in human CMV mononucleosis were observed during acute infection. These included anemia and leukocytosis with atypical lymphocytes. Splenomegaly and stimulation of spleen and lymph node T- and B-cell areas were also noted. These changes occurred at the peak of virus recovery from all tissues tested, as well as from macrophages and B- and T- cell-enriched spleen subpopulations. Virus was cleared rapidly from blood and bone marrow; blood counts, spleen size, and histology returned to normal within 1 month after virus inoculation. However, guinea pigs failed to eliminate the virus completely from lymphoid tissues, since virus persisted in splenic macrophage and B-lymphocyte-enriched populations during chronic infection. The data suggest that CMV-infected mononuclear cells play a role in the establishment of generalized acute infection and virus persistence.
Virulence of fungi: correlation of virulence of Blastomyces dermatitidis in vivo with escape from macrophage inhibition of replication in vitro
Authors: Brummer E , Morozumi P A , Philpott D E , Stevens D A
Published: January 2020

Strains of Blastomyces dermatitidis which are virulent (V), attenuated (A), or avirulent (AV) in mice have been identified. Virulence of V has been reported to be associated with its ability to replicate in vivo, causing lethal infections in the lungs or in the peritoneal cavity. We report here that V, but not A or AV, has the ability to replicate in vivo in nonlethal subcutaneous lesions. The possibility that V was able to replicate in vivo by evading primary host defenses was investigated. We studied the interaction of macrophages and strains of B. dermatitidis in vitro. In 24-h cocultures, the replication of all three strains of B. dermatitidis was inhibited by macrophages from: (i) untreated mice (20 to 40%), (ii) mice that had recovered from nonlethal blastomycosis (40 to 60%), (iii) concanavalin A-treated mice (50 to 70%), or (iv) peritoneal exudates elicited by thioglycolate (65 to 80%). However, at 72 h in the first three types of cocultures A and AV remained inhibited, whereas V was not inhibited (0 to 4%). Only the most inhibitory macrophages, those induced by thioglycollate, inhibited V at 72 h, though V was again less inhibited than A or AV at that time. Thus, we show a correlation between virulence of V in vivo and its ability to escape from macrophage inhibition of replication in vitro.
Human sex hormones stimulate the growth and maturation of Coccidioides immitis
Authors: Drutz D J , Huppert M , Sun S H , McGuire W L
Published: January 2020

Because men and pregnant women show increased susceptibility to extrapulmonary dissemination of coccidioidomycosis, studies were conducted to determine the direct effect of human sex hormones and related compounds on the growth and maturation of Coccidioides immitis in vitro. 17 beta-Estradiol, progesterone, and testosterone were highly stimulatory for the parasitic phase of C. immitis growth whereas cholesterol, ergosterol, and 17 alpha-estradiol (a physiologically inactive stereoisomer of 17 beta-estradiol) lacked such effects. Rates of spherule maturation and endospore release were accelerated, in a dose-dependent fashion, by concentrations of 17 beta-estradiol occurring in normal women, with the most striking effects seen at levels encountered in advanced pregnancy. A stimulatory effect of 17 beta-estradiol on the saprobic phase of fungal growth was also detected. The nonsteroidal "antiestrogens" tamoxifen and nafoxidine had either stimulatory or inhibitory effects, depending on fungal strain and experimental conditions. Diverse strains of Cryptococcus neoformans, Candida sp, and Petriellidium boydii were unaffected by hormones that had distinct effects on C. immitis. These studies suggest that direct stimulation of C. immitis by human sex hormones may help to account for sex- and pregnancy-related predisposition to dissemination of coccidioidomycosis.
Plasmids coding for colonization factor antigen I and heat-stable enterotoxin production isolated from enterotoxigenic Escherichia coli: comparison of their properties
Authors: McConnell M M , Smith H R , Willshaw G A , Field A M , Rowe B
Published: January 2020

We examined seven enterotoxigenic Escherichia coli strains which produced colonization factor antigen I (CFA/I). Four of these strains were from South Africa (three serotype O78:H12 and one serotype O63:H-), one was from Ethiopia (O78:H12), and two were from Bangladesh (O78:H11 and O78:H12). Plasmids coding for CFA/I were mobilized from six of these strains by using resistance or enterotoxin factors. No plasmid was mobilized from the serotype O78:H12 Bangladesh strain. The transconjugants obtained from crosses with the O78 strains also produced heat-stable enterotoxin (ST), and additional investigations showed that CFA/I and ST were coded for by a single non-autotransferring plasmid. These plasmids were fertility inhibition negative, did not restrict any of the coliphages with which they were tested, and were incompatible with each other. Four had molecular weights of approximately 60 X 10(6), and one had a molecular weight of 52 X 10(6). Like the other CFA/I plasmids, the CFA/I plasmid transferred from the O63:H- strain coded for ST, but this plasmid also coded for heat-labile enterotoxin. In most other respects the properties of this plasmid were similar to those of the CFA/I-ST plasmids previously described. The molecular weight of this plasmid was 65 X 10(6). The IncT R-factor Rtsl was marked with a transposon for tetracycline resistance and then transferred into the two Bangladesh wild-type strains. Plasmids which coded for tetracycline resistance, CFA/I, and ST were transferred from these strains. These plasmids were incompatible with Rtsl and with the CFA/I-ST plasmids described above and were recombinants between Rtsl and a CFA/I-ST plasmid. Their properties are also described.
Influence of the Fusogenic Agent Polyethylene Glycol on Attachment of
Mycoplasma pneumoniae
to Other Cells
Authors: Prakash Gyan , Gabridge Michael G.
Published: January 2020

The effect of fusogenic agents on the interaction of
Mycoplasma pneumoniae
with human lung fibroblasts was evaluated. A 60-s exposure of the fibroblasts to polyethylene glycol (molecular weight 200; 10%) significantly increased attachment of mycoplasmas to the fibroblasts.
Specific Capsular Polysaccharide of Type 46
Streptococcus pneumoniae
(American Type 73)
Authors: Benzing Laure , Carlo Dennis J. , Perry Malcolm B.
Published: January 2020

The specific capsular polysaccharide of type 46
Streptococcus pneumoniae
(American type 73) was isolated in pure form and shown to be a high-molecular-weight, glycosidically linked polymer composed of
d
-galactose (2 mol),
N
-acetyl-
d
-glucosamine (1 mol),
N
-acetyl-
d
-galactosamine (1 mol), and
N
-acetyl-
l
-fucosamine (1 mol).
Specific Capsular Polysaccharide of Type 45
Streptococcus pneumoniae
(American Type 72)
Authors: Daoust Virginia , Carlo Dennis J. , Zeltner Johanna Y. , Perry Malcolm B.
Published: January 2020

The specific capsular polysaccharide of type 45
Streptococcus pneumoniae
was isolated in pure form by chemical and chromatographic methods and found to be a high-molecular-weight, glycosidically linked polymer of a hexasaccharide repeating unit composed of D-galactose (2 mol), L-rhamnose (1 mol),
N
-acetyl-D-glucosamine (1 mol),
N
-acetyl-D-galactosamine (1 mol),
N
-acetyl-L-fucosamine (1 mol), and phosphate (1 mol).
Neutralizing antibody spectrum determines the antigenic profiles of emerging mutants of visna virus
Authors: Narayan O , Clements J E , Griffin D E , Wolinsky J S
Published: January 2020

The visna viruses are antigenically related nononcogenic retroviruses of sheep. The original strain was isolated from the brain of a paralyzed sheep in Iceland during the 1940s. The prototype strains has been passed serially in sheep and has undergone progressive antigenic change. Previous reports have shown that such antigenic changes in visna virus can be reproduced in infected cell cultures treated with neutralizing antibody. We now show that the antigenic profiles of the emerging mutants directly reflect the nature of the selecting antibody. Mutants with minor antigenic changes were selected by "early" sera which had a limited neutralization range. Mutants with greater antigenic changes were selected by "late" sera with a wide neutralization range. Mutants selected by early sera emerged rapidly and consistently in cultures, and these were antigenically very similar to one another. Mutants rarely emerged in cultures treated with late sera, but these viruses showed major antigenic changes. The data suggest that the evolution of antigenic mutants of visna virus progresses by a series of minor mutations which accumulate under the selective pressure of antibody.
Immune reactivity of the purified hemagglutinin of measles virus
Authors: Bellini W J , McFarlin D E , Silver G D , Mingioli E S , McFarland H F
Published: January 2020

The role of the immune response to measles virus in acute infection or in disease states associated with this virus is of major interest. The viral genome-specified surface antigens of measles, the hemagglutinin and fusion proteins, are likely to be of paramount importance with respect to the host immune response to the virus. This report describes initial studies aimed at assessing the immune response to the major surface glycoprotein, the hemagglutinin. This antigen was purified by affinity chromatography, using a monoclonal anti-hemagglutinin immobilized on Sepharose. The purified protein retained biological activity in hemagglutination assays. This activity could be specifically inhibited with a human antimeasles serum and with monoclonal antibody to the hemagglutinin. Lymphocytes from individuals known to proliferate to measles-infected monolayers also proliferated to the purified hemagglutinin. Thus, the immune-response to measles virus is, in part, directed to this surface antigen.
Possible importance of macrophage-derived mediators in acute malaria
Authors: Clark I A , Virelizier J L , Carswell E A , Wood P R
Published: January 2020

Tumor necrosis factor, lymphocyte-activating factor, and enhanced levels of type I interferon were found in serum samples taken 2 h after mice infected with Plasmodium vinckei subsp. petteri received a small intravenous injection of endotoxin. These three mediators are among those released when mice receive an endotoxin injection 2 weeks after Mycobacterium bovis BCG or Corynebacterium parvum have been administered. There is indirect evidence that this wider range of mediators is also released in P. vinckei subsp. petteri-infected mice given parenteral endotoxin. A recent report that endotoxin is detectable in the plasma of malaria-infected mice and children implies that these mediators may also be released in the acute phase of the natural infection. We propose that these macrophage-derived mediators may be important in the glucocorticoid antagonism, bone marrow depression, fever, hypergammaglobulinemia, splenomegaly, elevation of serum amyloid A, consumptive coagulopathy, and shock syndrome with associated organ damage which can accompany malaria. The intraerythrocytic parasite death seen at crisis in some malarias, as well as the subsequent development of specific protective immunity, may also depend on these mediators.
Characterization of macrophage functions in mice infected with Brucella abortus
Authors: Birmingham J R , Jeska E L
Published: January 2020

Macrophage spreading, surface receptor density/avidity, phagocytosis, random migration, chemotactic responsiveness, and serum lysozyme were examined during the course of infection (up to 60 days) of mice with Brucella abortus strain 19. Markedly enhanced in vitro spreading activity was observed throughout the period of study. The density/avidity of cell surface immunoglobulin G Fc receptors was increased for up to 60 days postinfection. Internalization of sheep erythrocytes via C3 receptors was significantly enhanced. Random locomotion and chemotactic responsiveness to lymphocyte-derived chemotactic factor and N-formyl-L-methionyl-L-leucyl-L-phenylalanine were markedly stimulated. Serum lysozyme was also elevated in infected animals. These changes indicated significant and prolonged enhancement of macrophage activity during Brucella infection. These findings are discussed in relation to previous reports describing macrophage activation by Brucella.
Indigenous nasopharyngeal, auditory canal, and middle ear bacterial flora of gerbils: animal model for otitis media
Authors: Thompson T A , Gardner D , Fulghum R S , Daniel H J , Allen W E , Worthington J M , Williams P P
Published: January 2020

The indigenous microbial flora of the middle ear cavity of Mongolian gerbils, Meriones unguiculatus, was isolated, characterized, and identified, showing it to be sparse and transitory. Organisms, when found in the middle ear cavity, were most likely to be Staphylococcus epidermidis-like organisms. Cerumen from the external auditory canal of these animals yielded mostly staphylococci, coryneforms, and other gram-positive rods, including some anaerobic species. The nasopharynx supported a flora consisting mainly of staphylococci, lactobacilli, and coryneforms, with a smaller incidence and numbers of many other species. No mycoplasmas were cultured or seen in scanning electron microscope studies. None of the major pathogens of human otitis media were found; therefore, Mongolian gerbils are microbiologically acceptable candidates as a model for induced otitis media, using organisms isolated from human otitic infections.
Initiation of the respiratory burst of human neutrophils by influenza virus
Authors: Mills E L , Debets-Ossenkopp Y , Verbrugh H A , Verhoef J
Published: January 2020

The role of the oxygen-dependent microbicidal systems of polymorphonuclear neutrophils in virus inactivation is not known. We found that isolated neutrophils responded to incubation with purified influenza virus A particles by consumption of oxygen, generation of chemiluminescence, and production of superoxide; these reactions occurred in the absence of serum. Resting leukocyte oxygen consumption doubled in the presence of virus; the average rate of consumption 2 to 12 min after virus was added was 1.54 nmol/10(7) cells per min. Live virus also stimulated superoxide production in a dose-dependent manner at a rate up to 4.54 nmol/10(7) cells per min. Luminol-amplified chemiluminescence was a rapid dose-dependent reaction which peaked 2 to 4 min after live or ultraviolet light-inactivated virus was added. No light was emitted when heat-inactivated virus particles were used, suggesting that heat-labile factors on the virus envelope may be involved in oxidative stimulation. Virus-stimulated neutrophils from a patient with chronic granulomatous disease emitted no light. The evidence that virus initiated the respiratory burst of neutrophils provided a potential mechanism for virus destruction, either by direct intracellular inactivation or by neutrophil-mediated cellular cytotoxicity of virus-infected target cells.
Relationship between cell surface composition of Candida albicans and adherence to acrylic after growth on different carbon sources
Authors: McCourtie J , Douglas L J
Published: January 2020

The adherence of Candida albicans to acrylic was measured in vitro after growth of the yeast to stationary phase in defined medium containing glucose, sucrose, galactose, fructose, or maltose as the carbon source. In each case, yeast adherence was proportional to the concentration of sugar in the growth medium, but equimolar concentrations of different sugars promoted adherence to different extents. In vitro adherence was further increased by the addition of divalent cations to assay mixtures but was inhibited when saliva-treated acrylic strips were used or when yeasts were suspended in mixed saliva during the assay. The rate of spheroplast formation of yeasts grown in media containing a 500 mM concentration of the different sugars correlated well with the relative adherence of the cells to acrylic. Galactose-grown yeasts were most resistant to spheroplast formation with Zymolyase-5000 and most adherent to acrylic, whereas fructose-grown organisms were least resistant to spheroplast formation and least adherent to acrylic. These results indicate that when grown to stationary phase in media containing high concentrations of certain sugars, C. albicans undergoes a change in cell surface composition which facilitates its adherence to acrylic surfaces. Electron microscopy of yeasts harvested from such media revealed the presence of an additional surface layer which may be responsible for this enhanced adherence.
Characterization of the Effector Cell That Mediates Cytotoxicity Against
Theileria parva
(East Coast Fever) in Immune Cattle
Authors: Emery David L. , Tenywa Tom , Jack Richard M.
Published: January 2020

After fractionation and depletion of peripheral blood leukocytes from cattle that were immune to
Theileria parva,
the effector cells which mediated cytotoxicity against parasitized autologous lymphocytes were considered to be thymusderived lymphocytes.
Fate of Listeria monocytogenes in resident and activated macrophages
Authors: Harrington-Fowler L , Henson P M , Wilder M S
Published: January 2020

A sensitive and highly reproducible assay was utilized to study in vitro interactions of Listeria monocytogenes with resident and activated macrophages. The technique is not compromised by extracellular events and can readily differentiate between the efficiency of ingestion and the postphagocytic fate of bacteria. Heat-labile factors in human or homologous serum markedly enhanced the phagocytosis of Listeria without noticeably affecting the intracellular fate of the microorganisms. The behavior of Listeria within macrophages cultivated from C57BL/6 and BALB/c mouse strains corresponded to previous reports of in vivo growth patterns in inbred mice. Thioglycolate- or caseinate-elicited macrophages, although highly phagocytic, were unable to prevent the proliferation of Listeria. A bactericidal macrophage population was derived from from C57BL/6 mice which had been immunized intraperitoneally with a sublethal dose of L. monocytogenes and subsequently boosted with heat-killed homologous organisms. Elicitation of immune animals produced an increase in the percentage of peroxidase-positive macrophages, but this activity could not be correlated with restriction of intracellular bacterial growth.
Identification of the active precipitin components in a purified preparation of the A antigen of Blastomyces dermatitidis
Authors: Young K D , Larsh H W
Published: January 2020

A purified A-antigen preparation of Blastomyces dermatitidis was determined to be composed of five major glycoprotein bands, visible with Coomassie blue and periodic acid-Schiff staining of polyacrylamide gels. At least 20 additional protein bands were detected by using a silver stain, which was 100 times more sensitive than the Coomassie method. Two components of this mixture were determined to be associated with the A-antigenic activity of B. dermatitidis. Of several antigen preparations examined in Ouchterlony precipitation tests, those reactive with a reference anti-A antiserum contained the slowest moving of the Coomassie blue bands. The antigen preparations without precipitin reactivity lacked this protein band. Two protein bands were shown to disappear from an antigen preparation after incubation with an affinity gel linked to the reference anti-A serum. One of the bands was the slowest Coomassie blue band, and the other was a fast-migrating protein detectable only with the silver stain. Characterization of the components responsible for the A-antigenic activity has important applications in the production and standardization of serological reagents for the diagnosis of blastomycosis.
Effects of proteolytic enzymes on the outer membrane proteins of Neisseria gonorrhoeae
Authors: Blake M S , Gotschlich E C , Swanson J
Published: January 2020

Proteolytic enzymes inhibit the growth of some strains and opacity variants of Neisseria gonorrhoeae. To understand the inhibitory effects of these enzymes, we examined several strains to determine the actions of proteases on the three predominant proteins in gonococcal outer membranes. namely, the major outer membrane protein (protein I), the sometimes-expressed opaque protein (protein II), and protein III. In a comparison of the protein I species expressed by different strains, we observed a pattern based on subunit molecular weight and susceptibility to enzymatic degradation. Protein I species having molecular weights of 34,000 were more susceptible to proteolysis, whereas protein I species having molecular weights of 33,000 were less susceptible, and protein I species having molecular weights of 32,000 were resistant. This pattern was observed both in intact cells and in purified outer membranes. All of the enzymes degraded protein II, but this susceptibility appeared to be influenced in part by the species of protein I present. Protein III was resistant to all of the proteolytic enzymes tested. Based on the resulting fragments from each proteolytic cleavage of proteins I and II and their membrane associations, we suggest how these proteins may be arranged in intact membranes. Our data suggested the presence of an endogenous gonococcal enzyme. This enzyme appeared to degrade proteins I and II into fragments resembling the fragments resulting from the action of chymotrypsin.
Dynamics of B-lymphocytes in the lungs of mice exposed to aerosolized influenza virus
Authors: Owens S L , Osebold J W , Zee Y C
Published: January 2020

Immunoglobulin-containing cells were revealed by immunofluorescence in lung sections from mice infected with influenza virus by the aerosol route. The numbers of immunoglobulin A (IgA)- and IgM-containing cells were increasing by day 3 of the infection, whereas IgG-containing cells appeared a few days later. The responding B-cell populations appeared in two principal locations: along major airways and in consolidated lesions within lung parenchyma. IgA-containing cells were the most numerous isotype, occurring predominantly in the lamina propria of the airways. IgG-containing cells were the least frequently encountered class along airways and appeared most often within consolidated lung lesions in clustered groupings. Cells staining for mu chain appeared along the airways and in lung lesions. The population of IgM-containing cells declined approximately 30 days after infection. Cells producing alpha and gamma chains were still numerous on day 46. Assays for virus-reactive antibodies in lung secretions were positive on day 8 of the infection. The IgM titers were the first to decline, but virus-binding antibodies for all classes were still present on day 33. The implications of immune responses in viral pneumonitis were considered.
Fate of phase I and phase II Coxiella burnetii in several macrophage-like tumor cell lines
Authors: Baca O G , Akporiaye E T , Aragon A S , Martinez I L , Robles M V , Warner N L
Published: January 2020

Several macrophage-like tumor cell lines of murine origin were exposed to phase I and phase II Coxiella burnetii, and the subsequent fate of the parasites was determined by electron and bright-field microscopy. Phase I C. burnetii proliferated within and established a persistent infection of P388D1, J774, and PU-5-IR cell lines but not of WEHI-3 and WEHI-274 cell lines. Phase II C. burnetii, however, entered into and persistently infected all five cell lines. The parasites proliferated within vacuoles. Macrophage cell lines persistently infected with phase I and phase II C. burnetii were maintained for over 200 and 100 days, respectively. Within P388D1 cells, the phase I C. burnetii converted, in part, to phase II; phase II organisms remained in the phase II state. The differential fate of the two rickettsial phases after exposure to the WEHI-3 and WEHI-274 cells may be attributable to surface differences such as lipopolysaccharide content.
Effect of host age on experimental K virus infection in mice
Authors: Greenlee J E
Published: January 2020

Mice were inoculated by the oral route with K virus at 4, 8, 12, and 23 days and at 4 months of age. The effect of host age on the pathogenesis of infection was studied by immunofluorescence, virus assay, and histopathology. K virus produced a systemic infection in all animals, although the infection because progressively more limited as animals matured. In mice inoculated at 4 days of age, K virus infection resulted in a fatal interstitial pneumonia identical to that seen in newborn animals and was characterized by the presence of virus and viral antigen in pulmonary and extrapulmonary vascular endothelia, reticuloendothelial organs, and brains. In older animals, K virus infection was clinically inapparent; organ involvement was similar in distribution to that seen in fatally infected suckling ice, but cells exhibiting specific viral fluorescence were fewer in number and viral titers were lower. Although animals surviving K virus infection developed high titers of hemagglutination inhibition antibody to the virus, positive cells and infectious virus could still be detected in intestines 2 months after inoculation. In animals inoculated at 8 and 12 days of age, in which K virus produced an extensive initial infection, virus could also be detected 56 days after inoculation in lungs, livers, spleens, and brains. The present study indicates that murine K virus produces a systemic infection throughout the life of its host and that the maturation of host defenses and the development of specific humoral immunity, although they limit dissemination of virus during acute infection, may not eliminate viral persistence in intestines or other organs once infection has occurred.
Persistent enhancement of cell-mediated and antibody immune responses after administration of muramyl dipeptide derivatives with antigen in metabolizable oil
Authors: Carelli C , Audibert F , Chedid L
Published: January 2020

Circulating antibody titers can be increased when the antigen is administered in an aqueous medium with N-acetylmuramyl-L-alanyl-D-isoglutamine (muramyl dipeptide). Results reported here show that cell-mediated immunity can be demonstrated when this synthetic adjuvant or an active analog is injected with an antigen (ovalbumin) in metabolizable squalane emulsion. Under these conditions a lipophilic derivative of muramyl dipeptide was shown to be even more active and to enhance long-lasting immune responses.
Streptolysin S activation by lipoteichoic acid
Authors: Theodore T S , Calandra G B
Published: January 2020

Lipoteichoic acid from streptococci and Staphylococcus aureus both activated membrane-bound precursor streptolysin S and induced the formation of extracellular streptolysin S. Lipoteichoic acid could replace other substances, such as yeast ribonucleic acid core, that act as carriers for hemolysin but which are not components of the streptococcus or the host. Lipoteichoic acid may play a role as the physiological carrier of streptolysin S to host tissues.
Activation of Complement by Cells Infected with Respiratory Syncytial Virus
Authors: Smith Thomas F. , Mcintosh Kenneth , Fishaut Mark , Henson Peter M.
Published: January 2020

The ability of respiratory syncytial virus (RSV)-infected HE
p
-2 cells in culture to activate complement was investigated. After incubation of cells with various complement sources and buffer, binding of C3b to surfaces of infected cells was demonstrated by immunofluorescence with a double-staining technique. Nonsyncytial and syncytial (i.e., fused, multinucleated) cells were separately enumerated. Also, lysis of RSV-infected cells was assessed by lactic dehydrogenase release. In this system only RSV-infected cells stained for C3b, and they did so only after incubation with functionally active complement. Blocking of classical pathway activation with ethylenediaminetetraacetic acid diminished the number of infected nonsyncytial cells positively stained for C3b, but had no effect on staining of syncytial cells. Blocking of alternative pathway activation with either zymosan incubation or heat treatment decreased the number of both syncytial and nonsyncytial cells stained for C3b. Decreasing immunoglobulin concentration of the serum used as the complement source also decreased numbers of both cell types stained for C3b. Eliminating specific anti-RSV antibody diminished numbers of both cell types stained for C3b, but staining was not eliminated. Lastly, incubation with functionally active complement markedly increased lactic dehydrogenase release from infected cells. This study demonstrated that RSV-infected nonsyncytial and syncytial cells are able to activate complement by both classical and alternative pathways. Activation of complement by syncytial cells appears to be less dependent on the classical pathway than is activation by nonsyncytial cells, and activation by syncytial cells may require immunoglobulin but not specific antibody. These experiments suggest the possibility of complement activation during respiratory tract infection by RSV. Implications of this are discussed.
Characteristics of a lipid preparation (lipid A) from Haemophilus influenzae type a lipopolysaccharide
Authors: Raichvarg D , Guenounou M , Brossard C , Agneray J
Published: January 2020

Mild hydrolysis of Haemophilus influenzae type a lipopolysaccharide by ion exchangers yielded a lipid A extracted by chloroform. It contained phosphorus, glucosamine, and fatty acids. Myristic, palmitic, 3-hydroxymyristic, and oleic acids and two other unidentified long-chain fatty acids were found. The free lipid A was not toxic for mice at doses of up to 50 mg/kg and did not provoke a Shwartzman reaction. The Limulus test activity was positive up to 10(-12) g/ml, but the pyrogenicity in rabbits was lower than with the original lipopolysaccharide. However, the lipid A did induced a mitogenic response and polyclonal B-cell activation in mouse spleen cell cultures. Complexing lipid A with bovine serum albumin gave a nontoxic preparation which lost these immunological activities. Immunochemical studies showed that the major reactive determinants of this lipid-protein complex were altered after such a linkage. Consequently, the nontoxic and mitogenic lipid A isolated from H. influenzae type a did not exhibit all of the classical activities of lipid A preparations.
Restriction endonuclease map of phage group 2 Staphylococcus aureus exfoliative toxin plasmid
Authors: Warren R L
Published: January 2020

A restriction endonuclease map of the phage group 2 Staphylococcus aureus exfoliative toxin plasmid pRW001 was constructed. The orientation of the restriction endonuclease fragments was determined by a series of single and double enzyme digestions. The location of the deletions found in pRW002, a naturally occurring deletion mutant of the exfoliative toxin plasmid, was determined by comparing the restriction endonuclease fingerprints of the two plasmids. This physical map provided a means for comparing other insertion or deletion mutants of the exfoliative toxin plasmid.
Lactose-reversible coaggregation between oral actinomycetes and Streptococcus sanguis
Authors: Kolenbrander P E , Williams B L
Published: January 2020

Freshly isolated strains of oral actinomycetes were obtained from human dental plaque and were tested for the ability to coaggregate with common laboratory stock strains of Streptococcus sanguis. Strains belonging to the genera Actinomyces, Arachnia, Bifidobacterium, and Bacterionema were isolated. Only members of the genus Actinomyces coaggregated with the streptococci, and only Actinomyces viscosus and Actinomyces naeslundii exhibited lactose-reversible interactions. A total of 61 strains, consisting of all of the A. viscosus isolates and 86% of the A. naeslundii isolates, coaggregated; 87% inhibited lactose-reversible coaggregation. On the basis of this property and the altered ability of strains to coaggregate after heat treatment of the cells, we delineated four coaggregation groups. The other 13% of the strains constituted a fifth group, which was characterized by a pattern of closely related interactions that were not reversed by lactose. Compared with previously characterized coaggregation properties determined with stock culture strains of actinomycetes, more than 80% of these fresh isolates exhibited identical coaggregation properties. Thus, most of the coaggregation between freshly isolated oral actinomycetes and streptococci involves lactose-reversible cell-cell interactions, which suggests that such coaggregation is mediated by a network of lectin-carbohydrate interactions between complementary cell surface structures on the two cell types.
Hypoglycemia in mice injected with interferon inducers is not mediated by interferon
Authors: Vignaux F , Gresser I
Published: January 2020

Injection of mice with several viral and nonviral inducers of interferon resulted in a marked hypoglycemia. Interferon is not responsible for this effect since inoculation of a potent antiserum to interferon (which neutralized the endogenous interferon) did not prevent hypoglycemia and administration of potent interferon preparations did not lower blood sugar. Hypoglycemia induced by Newcastle disease virus and polyriboinosinic-polyribocytidylic acid was further exacerbated by injection of insulin.
Demonstration of a lipopolysaccharide-induced cytostatic effect on malarial parasites
Authors: Rzepczyk C M , Clark I A
Published: January 2020

In an in vitro assay, malarial parasites (Plasmodium vinckei petteri) taken from mice 7 to 8 h after the injection of bacterial lipopolysaccharide (LPS) incorporated significantly less hypoxanthine into nucleic acid than did parasites from saline-treated controls. In contrast, incorporation was normal in parasites taken from mice within minutes of the injection of LPS and in parasites cultured with LPS. These results implied that the injection of LPS induced the release of mediators with a cytostatic effect on the parasite. This suggested an explanation for the protective action of LPS in malarial infections as well as for the "crisis forms" seen both in naturally resolving infections and in animals pretreated with such agents as BCG.
Distribution of superoxide dismutase, catalase, and peroxidase activities among Treponema pallidum and other spirochetes
Authors: Austin F E , Barbieri J T , Corin R E , Grigas K E , Cox C D
Published: January 2020

Representative members of Spirochaetales were surveyed for their content of superoxide dismutase (SOD), catalase, and peroxidase activities. Only Leptospira exhibited peroxidase activity. Obligately anaerobic cultivable Treponema and Spirochaeta possessed no SOD or peroxidative capabilities. Upon polyacrylamide gel electrophoresis, Spirochaeta aurantia, Borrelia hermsi, and five Leptospira biflexa serovars showed SOD activity associated with one electrophoretic band which was inhibited by H2O2, suggesting that they were iron-containing dismutases. These spirochetes could be distinguished by differences in relative mobilities of their SODs. SOD activity, but not catalase activity, was induced aerobically in S. aurantia. All Leptospira interrogans serovars and two L. biflexa serovars lacked significant SOD activity. These SOD-deficient strains of Leptospira, with one exception, possessed high levels of catalase activity. The Nichols strain of virulent Treponema pallidum possessed SOD and catalase activities, but lacked peroxidase activity. The SOD in T. pallidum exhibited two electrophoretic bands containing copper and zinc, and its relative mobility was identical to that of purified rabbit SOD. Immunization of sheep with purified rabbit SOD resulted in antiserum which inhibited both rabbit SOD and T. pallidum SOD assayed by spectrophotometric analysis or activity staining following polyacrylamide gel electrophoresis. In agarose gel diffusion, precipitin lines of identity were observed between purified rabbit SOD and cell extracts of T. pallidum. These data indicated that the SOD activity detected in T. pallidum was host derived.
Detection and composition of immune complexes in experimental African trypanosomiasis
Authors: Lindsley H B , Janecek L L , Gilman-Sachs A M , Hassanein K M
Published: January 2020

Humoral immune responses in experimental African trypanosomiasis were assessed in rabbits infected with Trypanosoma rhodesiense. Immune complexes as measured by a Clq binding assay or a Clq solid-phase assay were detected by day 10 and increased progressively through day 28. Immune complexes analyzed by double diffusion in agar or enzyme immunoassay contained immunoglobulin M (IgM) and IgG consistently, and usually C3. In one serum, immune complexes contained trypanosomal antigens in addition to C3, IgG, and IgM. By sucrose density gradient ultracentrifugation Clq-binding immune complex-like materials were shown to contain IgG, IgM, and C3, sedimentating as intermediate (between 7S and 19S) or as higher-molecular-weight (greater than 19S) aggregates. Serum IgM and IgG antibodies to trypanosomes were measured by enzyme immunoassay. IgM antibodies were detected by day 7, rose to peak by day 14, and declined slowly thereafter. IgG antibodies were detected by day 14 and continued to rise through day 32. Total IgM and IgG measured by radial immunodiffusion paralleled the corresponding changes in antibody levels. Host immune responses, in part directed to trypanosomal antigens, produced circulating immune complexes containing bound C3; these may be deposited in tissue or may serve as a serological marker of immune complex-mediated tissue injury.
Effects of in vivo dexamethasone administration on in vitro bovine polymorphonuclear leukocyte function
Authors: Roth J A , Kaeberle M L
Published: January 2020

Polymorphonuclear leukocyte function was evaluated in vitro after in vivo administration of a single dose of dexamethasone to cattle. Purified polymorphonuclear leukocytes from dexamethasone-treated cattle displayed enhanced random migration under agarose but impaired ingestion of Staphylococcus aureus, Nitro Blue Tetrazolium reduction, chemiluminescence, iodination, and antibody-dependent, cell-mediated cytotoxicity. The depression of iodination may have been related to a drop in the proportion of eosinophils present in the polymorphonuclear leukocyte preparations after dexamethasone administration.
Blastomyces dermatitidis antigen-induced lymphocytes reactivity in human blastomycosis
Authors: Bradsher R W , Alford R H
Published: January 2020

Because of the unavailability of a suitable antigen, specific in vitro lymphocyte reactivity has not been investigated in persons who have had systemic blastomycosis. Twelve persons who had recovered from blastomycosis were evaluated, and all were found to exhibit strongly positive and apparently specific in vitro cellular responses to an alkali-soluble, water-soluble extract of Blastomyces dermatitidis yeast-phase cell walls. Significant lymphocyte transformation induced by this soluble antigen occurred with cells from persons who had recovered from blastomycosis as much as 16 years previously, indicating long-lasting cell-mediated immunity to B. dermatitidis. A simple new in vitro test, lymphocyte migration inhibition, also made it possible to distinguish persons who had had blastomycosis and recovered from persons who had never had the disease. Two in vitro tests of cell-mediated immunity in which the alkali-soluble, water-soluble extract of B. dermatitidis yeast-phase cell walls was employed were highly discriminating. Tests with this antigen may be of value in delineating the epidemiology of blastomycosis and in assessing the prognosis of individual cases.
Serum bactericidal effect on Pseudomonas aeruginosa isolates from cystic fibrosis patients
Authors: Thomassen M J , Demko C A
Published: January 2020

The bactericidal activity against Pseudomonas aeruginosa strains isolated from cystic fibrosis patients was determined in a 10% concentration of normal serum or autologous cystic fibrosis serum. Of the 167 strains tested, 77 (46%) were sensitive (greater than 95% killed) in normal serum. Mucoid strains were more frequently sensitive than nonmucoid strains. Twenty-three sensitive strains tested in ethyleneglycoltetraacetic acid-chelated serum were resistant (less than 10% killed), suggesting only classical pathway activation. Absorption of cystic fibrosis serum with the autologous P. aeruginosa strain resulted in decreased killing by that serum. All sera, including the chelated and absorbed sera, had comparable total hemolytic complement levels. Patients in poor clinical condition (5 out of 12), in contrast to patients in good or moderate condition(1 out of 30), were more likely to have P. aeruginosa strains that were serum resistant in autologous serum but sensitive in normal serum. Sera from these five patients in poor clinical condition were capable of killing heterologous P. aeruginosa strains. These results suggest the presence of a protective or "blocking" activity in serum from some patients in poor clinical conditions. This association of a blocking activity with clinical condition may signal a transition point in the progression of cystic fibrosis lung disease and thus may be another contributory factor in the failure of the cystic fibrosis host to control infection.
Rabbit cationic protein enhances leukocyte adhesiveness
Authors: Oseas R S , Allen J , Yang H H , Baehner R L , Boxer L A
Published: January 2020

Cationic protein purified from rabbit peritoneal polymorphonuclear leukocytes (PMN) was demonstrated to incite autoaggregation of the rabbit PMN and promote adhesiveness of human PMN to endothelial cells. PMN aggregation induced by supernatants derived from secretory PMN was blocked by a specific anticationic protein antibody. These studies reveal that a positively charged protein derived from the PMN can alter surface properties of the PMN itself and imply a role for this protein in PMN immobilization at inflammatory sites.