bluuebunny/crossref_metadata_2025 huggingface dataset:
Antibody-Dependent Cell-Mediated Cytotoxicity in Cattle: Activity Against
51
Cr-Labeled Chicken Erythrocytes Coated with Protozoal Antigens
Authors: Duffus W. P. H. , Butterworth A. E. , Wagner G. G. , Preston J. M. , Franks D.
Published: January 2020

Bovine mononuclear cells in the presence of bovine anti-chicken erythrocyte sera at high dilutions induce release of chromium-51 from labeled chicken erythrocytes. Bovine effector cells are capable of recognizing both bovine immunoglobulin G
1
and bovine immunoglobulin G
2
; in contrast, human effector cells only recognize immunoglobulin G
1
. Effector cell activity of bovine mononuclear cells is equally distributed between peripheral blood and spleen. As in other species, thymus and lymph node cells exert no antibody-dependent effect, although some direct cytotoxicity by lymph node cells may be observed. Antibody-dependent cell-mediated cytotoxicity against a bovine cell line can also be detected. By using a tannic acid technique, it was found that chicken erythrocytes coated with
Theileria parva
piroplasm antigen or with
Trypanosoma rhodesiense
variant-specific coat antigen form suitable targets for bovine antibody-dependent cell-mediated cytotoxicity assays. By using such targets, a moderate degree of direct cytotoxicity by bovine mononuclear cells, in the absence of antibody, is always observed; this may be reduced by choosing optimal conditions of tannic acid treatment and antigen sensitization and by the use of short incubation periods for the cytotoxicity assay. Observations have been made on the variant specificity, time course of appearance, and association with immunoglobulin G
1
of the antibody activity responsible for cell-dependent cytotoxicity against chicken erythrocytes coated with
T. rhodesiense
antigens. The potential usefulness of this technique in the analysis of protective immune responses against protozoal infections is discussed.
Complement activation in acne vulgaris: in vitro studies with Propionibacterium acnes and Propionibacterium granulosum
Authors: Webster G F , Leyden J J , Norman M E , Nilsson U R
Published: January 2020

To better define the role of bacteria in inflammatory acne vulgaris, we have investigated the ability of four strains of Propionibacterium acnes and three strains of Propionibacterium granulosum to activate complement. Complement activation was assayed by incubating normal human serum with varying concentrations of each strain and measuring residual total hemolytic complement activity. When serum was tested unaltered, P. acnes strains were approximately threefold more potent than an equal weight of P. granulosum in consuming complement, which could reflect classical and/or alternative pathway activation. All strains also consumed complement in serum chelated with ethyleneglycol-bis (beta-aminoethyl ether)-N,N'-tetraacetic acid, which selectively assays alternative pathway activation. Incubation of unaltered serum with both P. acnes and P. granulosum resulted in immunoelectrophoretic conversion of C4, C3, and factor B of the alternative pathway. Incubation of chelated serum resulted in conversion of C3 and factor B. These data taken together suggest that both species can activate complement through either pathway. Serum incubated with P. acnes was chemotactic for polymorphonuclear leukocytes, and this chemotactic activity was largely C5 dependent as shown by antibody inhibition. It is suggested that complement activation may occur in vivo in acne, and the inflammatory response may be contributed to by the generation of C5-dependent chemotactic factors.
Induction of enhanced resistance against encephalomyocarditis virus infection of mice by nonviable Mycobacterium tuberculosis: mechanisms of protection
Authors: Lodmell D L , Ewalt L C
Published: January 2020

Nonviable Mycobacterium tuberculosis strain Jamaica suspended in oil-droplet emulsions was used to enhance resistance of mice against encephalomyocarditis virus (EMCV). The mycobacteria-injected mice were significantly resistant to 50,000 50% lethal doses of EMCV. Similar concentrations of virus in plasma of normal and mycobacteria-injected mice from 1 to 120 min after injection of EMCV showed that resistance was not a result of rapid elimination of virus from the circulation. Furthermore, survival of viremic mice indicated protective mechanisms were operative after EMCV had escaped primary surveillance. Resistance did not appear to be associated with the mouse major histocompatibility gene complex. The spleen was intimately associated with protection, and the thymus was nonessential for enhanced resistance to EMCV. Protection was significantly diminished by cyclophosphamide injected intraperitoneally from 3 days before to the day of virus challenge. Finally, silica given intraperitoneally 24 h before virus completely abrogated resistance of mycobacteria-injected mice to EMCV. These results suggest that macrophages functioning independently of T-lymphocytes are important effector cells in resistance to EMCV of mice injected with nonviable mycobacteria.
Immunization of suckling pigs against enterotoxigenic Escherichia coli-induced diarrheal disease by vaccinating dams with purified 987 or K99 pili: protection correlates with pilus homology of vaccine and challenge
Authors: Morgan R L , Isaacson R E , Moon H W , Brinton C C , To C C
Published: January 2020

Pregnant gilts were vaccinated with purified strain 987 pili (987P), strain K99 pili, or a saline-formaldehyde control. Suckling pigs born to vaccinated gilts were allowed to consume colostrum and were then challenged intragastrically with one of three enterotoxigenic Escherichia coli strains: 987 (O9:K103, 987P:NM), 74-5208 (02O:K101, 987P:NM) or 431 (O101:K30, 99:NM). In litters where the dam was vaccinated with the same pilus as that possessed by the challenge organism, the incidence and duration of diarrhea and the degree of intestinal colonization (either duration or extent) were less than those of the other vaccine groups. Surviving pigs in the homologous vaccine groups also had better weight gains than pigs in the other vaccine groups. The experiments extend and confirm previous reports that vaccination of the dam with purified pili confers protection to neonatal suckling pigs against diarrheal disease caused by enterotoxigenic E. coli strains that possess the same pili. Protection did not extend to enterotoxigenic strains possessing different pili.
Effects of Acquired Resistance on Infection with
Eimeria falciformis
var.
pragensis
in Mice
Authors: Mesfin G. M. , Bellamy J. E. C.
Published: January 2020

Mice immunized with infections of 500, 5,000, or 20,000 oocysts of
E. falciformis
var.
pragensis
were reinfected with 20,000 and 100,000 oocysts at 20 and 38 days, respectively, after the initial infection. After the first challenge infection, none of the immunized mice showed clinical signs of coccidiosis; a few mice passed very low numbers of oocysts, and oocyst discharge seemed to correlate negatively with immunizing dose. None of the mice immunized twice passed oocysts after challenge. Mice immunized with three infections were completely immune to challenge for 4 months. The effect of the immune response on the life cycle of the coccidium was determined by histological examination of the intestines of immune and nonimmune mice infected with the parasite. In both the immune and nonimmune groups, sporozoites penetrated absorptive epithelial cells and migrated to crypt epithelial cells during the first 6 to 24 h postinfection. At 48 to 72 h postinfection, the sporozoites developed into mature first-generation schizonts in the nonimmune mice, whereas the developing first-generation schizonts degenerated within the crypt epithelial cells of the immune mice. In nonimmune mice, third-generation merozoites, inoculated intracecally, developed into mature fourth-generation schizonts, whereas in immune mice the developing fourth-generation schizonts degenerated before maturing. The possibility that a cellmediated immune mechanism is responsible for the arrest in schizogony is discussed.
Stimulation of T-independent antibody responses by hapten-lipopolysaccharides without repeating polymeric structure
Authors: Skelly R R , Munkenbeck P , Morrison D C
Published: January 2020

The murine immune response to a haptenated lipopolysaccharide (LPS) lacking repeating oligosaccharide determinants was studied. The LPS was extracted from a rough strain of bacteria (Salmonella minnesota R595) and chemically haptenated with either trinitrophenol or fluorescein isothiocyanate. These preparations of hapten-R595 LPS were shown to be immunogenic. Furthermore, the immune response to the hapten was demonstrated to occur independent of T cells and was not merely the result of enhanced polyclonal B-cell activation. The capacity of such hapten-LPS conjugates without repeating polymeric structures to stimulate T-independent antibody responses provides information on the molecular requirements for the activation of murine B lymphocytes.
Persistence of avian oncoviruses in chicken macrophages
Authors: Gazzolo L , Moscovici C , Moscovici M G
Published: January 2020

Inoculation of avian oncoviruses into 1- to 2-month old chickens led to a rapid production of antiviral humoral antibodies. Under these conditions it was found that avian leukosis viruses are sequestered in macrophages of peripheral blood, in which they can persist for a long period of time (up to about 3 years). In contrast, avian sarcoma viruses were never found in macrophages from chickens during the progression of sarcomas or after regression of the tumors.
Experimental sporotrichosis in Syrian hamsters
Authors: Charoenvit Y , Taylor R L
Published: January 2020

Syrian hamsters were infected with Sporothrix schenckii by subcutaneous footpad inoculation. Two types of infection could be uniformly induced: a self-limited, lymphatic infection resembling the classical disease in humans, and a generalized nonfatal infection. An infecting dose of approximately 5,300 yeast cells produced the localized subcutaneous-lymphatic disease which was limited to a single limb. In contrast, a 1,000-fold increase in the inoculum temporarily overwhelmed the animals' defense mechanisms, producing a systemic infection involving the liver and spleen. These models were used to demonstrate the development of increased resistance to subsequent infection following either infection or active immunization with ribosomal fractions or trypsinized cell wall antigens of S. schenckii incorporated in Freund complete adjuvant. Agglutination titers were detectable in all animals that were either infected or immunized. In one group of infected animals, the titers persisted for at least 1 year after three booster doses of Formalin-killed S. schenckii. The ability to produce an infection in hamsters which closely resembles the disease seen in humans makes the animal a good model with which to study experimental sporotrichosis.
Translocation of Certain Indigenous Bacteria from the Gastrointestinal Tract to the Mesenteric Lymph Nodes and Other Organs in a Gnotobiotic Mouse Model
Authors: Berg Rodney D. , Garlington Alva W.
Published: January 2020

Viable bacteria were not cultured from the mesenteric lymph nodes, spleens, or livers of specific-pathogen-free (SPF) mice. Viable enteric bacteria, primarily indigenous
Escherichia coli
and lactobacilli, were present in the mesenteric lymph nodes of gnotobiotic mice inoculated intragastrically with the whole cecal microflora from SPF mice but not in the nodes of control SPF mice similarly inoculated. These indigenous
E. coli
also were cultured from the mesenteric lymph nodes of 96% of gnotobiotic mice monoassociated with
E. coli
but from none of the mesenteric lymph nodes of SPF mice inoculated with the
E. coli.
Furthermore, viable
E. coli
were detected in the mesenteric lymph nodes of these monoassociated gnotobiotes for as long as 112 days after inoculation. Indigenous
Lactobacillus acidophilus
also translocated to the mesenteric lymph nodes of gnotobiotic mice monoassociated with
L. acidophilus.
Apparently, there are mechanisms active in SPF mice inhibiting translocation of indigenous bacteria from the gastrointestinal tract to the mesenteric lymph nodes, spleens, and livers, whereas these mechanisms are either absent or reduced in gnotobiotic mice. Indigenous
E. coli
maintained higher population levels in the gastrointestinal tracts of the gnotobiotes compared with their population levels in SPF mice, suggesting that high bacterial population levels might promote translocation of certain bacteria from the gastrointestinal lumen to the mesenteric lymph nodes. Gnotobiotic and SPF mice, therefore, provide experimental models for determining the nature of the mechanisms operating to confine indigenous bacteria to the gastrointestinal tract in normal, healthy animals.
Characteristics of lipid A-protein complex from endotoxin of Shigella dysenteriae type 1 (S and R strains)
Authors: Sourek J , Trnka T , Levin J , Roubal J , Michalec C
Published: January 2020

Mild acetic acid hydrolysis of endotoxin (lipopolysaccharide-protein complex) of Shigella dysenteriae type 1 (S and R forms) yielded a lipid A-protein complex that consisted of amino acids, fatty acids, and sugar and, in terms of chemical composition, displayed no marked differences between the S and R forms. Its protein portion (53 to 56%) consisted of at least 16 amino acids. In the fatty acid portion (14 to 18%), myristic, 3-hydroxymyristic, palmitic, and stearic acids accounted for 50%. The sugar portion (10 to 12%) consisted solely of glucosamine. The remainder was unidentified substances, most of which contained phosphorus. Lipid A-protein complexes derived from both S and R forms were not toxic for mice in doses up to 1,000 microgram/mouse, but their Linulus test activity had increased considerably as compared with the starting lipopolysaccharide-protein complex material: from 10(-6) to 10(-10--10(-12) mg/ml. The lipid A-protein complexes were readily soluble in a water solution of triethylamine, in dimethyl sulfoxide, and in pyridine.
Effect of salts on water-insoluble glucan formation by glucosyltransferase of Streptococcus mutans
Authors: Mukasa H , Shimamura A , Tsumori H
Published: January 2020

The formation of water-insoluble glucan by extracellular glucosyltransferase from Streptococcus mutans 6715 found to be greatly stimulated by various mono- or divalent cations. An enzyme preparation, obtained by ethanol fractionation, was able to catalyze the formation of water-insoluble glucan from sucrose in the presence of monovalent cations above 100mM or divalent cations above 20 mM at neutral pH. As the concentration of monovalent and divalent cations was reduced to below 10 mM and 1 mM, respectively, the formation of insoluble glucan decreased to a negligible amount. High concentrations of these cations were found to stimulate the formation of insoluble glucan in the following ways: (i) it increased the activity of total glucosyltransferase up to 1.6- and 2.7-fold in the absence and presence of a primer dextran, respectively, and (ii) it changed the formation of soluble glucan to insoluble. It was postulated that one of the essential factors for the formation of insoluble glucan would be to keep more than two water-soluble glucan chains close to enzyme aggregates and that such interaction could be enhanced by the presence of high cation concentrations.
Role of complement in the expression of delayed-type hypersensitivity in rats: studies with cobra venom factor
Authors: Jungi T W , McGregor D D
Published: January 2020

The hypothesis was tested that delayed-type hypersensitivity (DTH) to the complement-activating bacterium Listeria monocytogenes is initiated by complement-derived mediators that attract sensitized lymphocytes to reaction sites. To this end DTH and acquired resistance to L. monocytogenes were measured in rats injected with cobra venom factor, a potent inactivator of C3. Treatment with cobra venom factor reduced the hemolytic power of serum to less than 0.5% of the control value. Such decomplemented animals expressed both DTH and antimicrobial resistance, although expression of DTH was reduced (ca. 50%) when compared with complement-sufficient controls. The observed depression of DTH in cobra venom factor-treated rats was associated with a reduction in the number of recently activated lymphocytes (lymphoblasts) and macrophages that accumulated in DTH reaction sites. The above findings are explained, in part, by inhibition of inflammation during the early postinduction period. Supporting evidence came from measurements of labeled lymphoblast sequestration in saline injection sites and the slower accumulation of macrophages in nitrocellulose filters that were implanted subcutaneously in complement-depleted rats. The ability of cobra venom factor-treated rats to express DTH and protect themselves against a Listeria challenge seems to exclude C3-dependent factors as essential mediators in the attraction of antigen-reactive lymphocytes to reaction sites.
Experimental Eikenella corrodens endocarditis in rabbits
Authors: Badger S J , Butler T , Kim C K , Johnston K H
Published: January 2020

The ability of Eikenella corrodens to cause endocarditis in catheterized rabbits was studied. E. corrodens 1073, the serum-resistant strain used in the study, was isolated from a human periodontitis lesion. Thirty-four rabbits, surgically catheterized across the aortic valve and injected intravenously 24 to 48 h later with 10(7) to 10(9) log-phase organisms, were studied. Only three rabbits developed positive blood cultures and only two rabbits died before the time of sacrifice at 14 days after infection. Autopsies showed that all rabbits developed aortic vegetations, 52% of which were culture positive for E. corrodens. The organisms were recovered from aortic vegetations in a mean concentration of 10(5.3) colony-forming units/g of tissue and from liver or kidney in 28% of the animals in concentrations from 10(2) to 10(4) colony-forming units/g. Indirect immunofluorescent staining of vegetations, with the use of specific rat antiserum to E. corrodens 1073 and fluorescein isothiocyanate-labeled goat antirat serum, revealed colonies of E. corrodens in culture-negative vegetations as well as in those which were culture positive. The results showed that E. corrodens was an effective pathogen in the rabbit model of endocarditis, in which the disease was infrequently bacteremic and rarely fatal.
Interaction of inflammatory cells and oral microorganisms. VIII. Detection of leukotoxic activity of a plaque-derived gram-negative microorganism
Authors: Baehni P , Tsai C C , McArthur W P , Hammond B F , Taichman N S
Published: January 2020

In the present study we identified a gram-negative anaerobic rod referred to as Y4 which was cytotoxic for human polymorphonuclear leukocytes. Y4 was isolated from dental plaque of a patient with juvenile periodontitis and presented most of the taxonomic characteristics of Actinobacillus species. Under experimental conditions, viable Y4 were cytotoxic for human peripheral blood polymorphonuclear leukocytes in serum-free cultures. Cytotoxicity was dependent on bacterial concentrations and was enhanced in the presence of a fresh or heat-inactivated (56 degrees C, 30 min) autologous serum. Leukotoxicity was independent of phagocytosis. Y4 leukotoxic effect was abolished when bacteria were heat treated (56 degrees C, 30 min) or when incubations were carried out at 4 degrees C instead of at 37 degrees C. The leukotoxicity was monitored by electron microscopy and biochemically by measuring lactate dehydrogenase indicator of cell viability. No cytotoxic effects of Y4 on human mononuclear cells, chicken fibroblasts, or mouse macrophages were detected under the conditions studied. Polymorphonuclear leukocytes may play an important role in the host defense against bacteria in periodontal disease. The cytotoxic effect of Y4 for polymorphonuclear leukocytes presented in this study is the first report of a direct offensive microbial vector in a plaque-derived microorganism and may prove to be relevant in the pathogenesis of juvenile periodontitis.
Mucopolysaccharidase of
Treponema pallidum
Authors: Fitzgerald T. J. , Johnson R. C.
Published: January 2020

Treponema pallidum
(Nichols strain) exhibited mucopolysaccharidase activity. Acidic mucopolysaccharides were broken down more rapidly by viable treponemes than by heat-inactivated treponemes or membrane filtrates of treponemal suspensions. Ouchterlony immunodiffusion demonstrated the occurrence of antibodies to the hyaluronidase-like enzyme within syphilitic sera. After intratesticular inoculation of 2 × 10
7
to 6 × 10
7
treponemes, these anti-mucopolysaccharidase antibodies were detected between 9 and 35 days postinoculation. In addition, acidic mucopolysaccharides were present in the serum of infected animals 9 and 16 days postinoculation. Immune serum that contained antibodies to the mucopolysaccharidase restricted treponemal breakdown of acidic mucopolysaccharides. It has been previously demonstrated that immune rabbit serum contains a factor that blocks attachment of
T. pallidum
(Nichols strain) to cultured mammalian cells. This factor was effectively absorbed by prior incubation with bovine hyaluronidase. It is postulated that
T. pallidum
attaches to acidic mucopolysaccharides on the surface of cultured cells through the mucopolysaccharidase enzyme at the surface of the organisms. These findings are discussed in terms of the histopathogenesis of
T. pallidum
with applications to the healing immune response.
Local antibody response in chickens: analysis of antibody synthesis to Newcastle disease virus by solid-phase radioimmunoassay and immunofluorescence with class-specific antibody for chicken immunoglobulins
Authors: Ewert D L , Barger B O , Eidson C S
Published: January 2020

The antibody response to Newcastle disease virus was monitored in the sera and salivas of adult chickens immunized by two methods: (i) combined intratracheal-intranasal vaccination followed by intratracheal revaccination or (ii) intramuscular vaccination followed by intratracheal revaccination. By solid-phase radioimmunoassay, only immunoglobulin G (IgG) and IgA antibodies to Newcastle disease virus were detected in the salivas, whereas IgA and IgM antibodies were present in egg whites. The first method produced the highest antibody levels in both serum and saliva and, in addition, prevented detectable virus multiplication in the respiratory tracts upon revaccination 4 weeks later. Plasma cells of all three classes were distributed throughout the tissues lining the oral cavities. The highest densities of plasma cells were in the Harderian glands; IgG was the predominant class, whereas IgA and IgM plasma cells were present in almost equal but lower numbers. The Harderian plasma cells were the most likely source of the antibody found in saliva.
Inhibition of adenosine 3',5'-monophosphate-dependent protein kinase by staphylococcal alpha-toxin
Authors: Kato I , Watanabe M , Kumazawa N H
Published: January 2020

Staphylococcal alpha-toxin inhibited the activity of cyclic adenosine 3',5'-monophosphate-dependent protein kinase by competitive inhibition, probably by its interaction with a cyclic adenosine 3',5'-monophosphate-binding site in the protein kinase molecule.
Experimental reproduction of neonatal diarrhea in young gnotobiotic hares simultaneously associated with Clostridium difficile and other Clostridium strains
Authors: Dabard J , Dubos F , Martinet L , Ducluzeau R
Published: January 2020

Clostridium difficile, C. perfringens, and C. tertium are very often present simultaneously in the feces of conventional diarrheic young hares, whereas these three bacterial species are rarely encountered and never present simultaneously in the feces of healthy young hares. When a strain of each of the three bacterial species was monoassociated with axenic young hares, the appearance of pathological disorders was only observed in animals monoassociated with C. difficile, when the number of C. difficile exceeded 10(8) per g of fresh feces. When a strain of C. perfringens or a strain of C. tertium, or both, was associated with C. difficile, diarrhea and death occurred more rapidly than in hares monoassociated with C. difficile. C. difficile and C. perfringens became established more rapidly when disassociated than when monoassociated with axenic hares. The association of C. perfringens and C. tertium with axenic hares did not bring about any pathological disorders. It may be concluded that C. difficile is the causal agent of neonatal diarrhea in conventional and gnotobiotic young hares and that other strains of Clostridium enhance its pathogenic effect. C difficile alone or associated with C. perfringens or C. tertium does not play any pathogenic role in young rats, mice, or rabbits.
Mouse protective capabilities of Escherichia coli hybrids expressing Salmonella typhi antigens
Authors: Diena B B , Lior H , Ryan A , Krol P , Johnson E M , Baron L S
Published: January 2020

An Escherichia coli hybrid, F1061, expressing Salmonella typhi somatic antigens 9 and 12, and a derivative of this hybrid, E. coli hybrid WR3078, expressing the S. typhi Vi antigen in addition to somatic antigens 9 and 12, were compared with S. typhi Ty2 in experiments to test their ability, as live vaccines, to protect Swiss white mice against death from challenge with a mouse-virulent Salmonella typhimurium hybrid expressing the S. typhi antigens 9, 12, Vi, and d. When the live, vaccinating organisms were administered intraperitoneally, 87.5% of the mice immunized with S. typhi Ty2 survived challenge, as compared with 62.5% of those immunized with E. coli hybrid F1061 and 55% of those inoculated with E. coli hybrid WR3078. When live organisms were administered orally at a dose of 10(9), 67.5% of the mice immunized with S. typhi Ty2 survived challenge as compared with 47.5% of those immunized with E. coli hybrid F1061 and 40% of those administered E. coli hybrid WR3078. Thus, the protection conferred by E. coli hybrid F1061 expressing only the S. typhi somatic antigens, although significant in this system, was inferior to that conferred by S. typhi Ty2 and the addition of the S. typhi Vi antigen to this hybrid (creating E. coli hybrid WR3078) did not enhance that protection.
Stimulation of the reticuloendothelial system of mice by muramyl dipeptide
Authors: Tanaka A , Nagao S , Nagao R , Kotani S , Shiba T , Kusumoto S
Published: January 2020

Muramyl dipeptide (MDP), a part of bacterial cell wall peptidoglycans, was active as adjuvant and stimulated the reticuloendothelial system (RES) of mice to increase its phagocytic function. A series of analogs of MDP was tested for their adjuvant activity and RES-stimulating activity. Sex differences were observed in the adjuvant activity and RES-stimulating capacity of some MDP analogs. A stereochemically highly specific structure required for MDP to exert adjuvant activity was also required for its RES-stimulating activity. Based on this close correlation among the structure, adjuvant activity, and RES-stimulating capacity of MDP, we infer that macrophages may play an important role in the expression of adjuvant activity of MDP.
Comparative Behavior of Virulent Strains of
Treponema pallidum
and
Treponema pertenue
in Gradient Cultures of Various Mammalian Cells
Authors: Fieldsteel A. Howard , Stout James G. , Becker Frances A.
Published: January 2020

Two strains of virulent
Treponema pallidum
and two of virulent
T. pertenue
were investigated for their ability to attach to and survive in gradient cultures of five different mammalian cells under aerobic conditions. The strains of
T. pallidum
studied were the high-rabbit-passage Nichols and the low-rabbit-passage KKJ. The former was known to readily attach to cottontail rabbit epithelial cells (Sf1Ep) and to survive in the virulent state for up to 21 days. We therefore compared attachment of the other virulent treponemes with that of
T. pallidum
(Nichols). The KKJ strain of
T. pallidum
behaved in a fashion similar to
T. pallidum
(Nichols) in all of the cultures. Both strains exhibited preferential attachment to cells of Sf1Ep and those derived from the ear of a nude athymic (nu/nu) mouse. In these cultures, we observed a consistent three- to fivefold increase in attached treponemes up to 12 days after initial inoculation. The strains of
T. pertenue
were the human-derived Gauthier and cynocephalus-derived FB. These two strains of
T. pertenue
also attached to cells of all five types of cultures, but in smaller numbers than were seen with
T. pallidum
and equally to all of the cultures. Neither preferential attachment to Sf1Ep and nude mouse ear cells nor increased attachment with time was seen.
Antibacterial activity of bladder surface mucin duplicated by exogenous glycosaminoglycan (heparin)
Authors: Parsons C L , Mulholland S G , Anwar H
Published: January 2020

We have previously shown that the transitional cells lining the urinary bladder are capable of producing glycosaminoglycan (GAG). By use of a quantitative in vivo method of measuring bacterial adherence, we demonstrated that bacterial adherence to the mucosal cells is diminished in the presence of this GAG, rises when it is removed (by acid), and returns to normal when the GAG is resynthesized (in less than 24 h). We also found that this much layer could be removed (with a corresponding rise in bacterial adherence) and that addition of exogenous GAG (heparin) to the bladder prevented the expected rise in bacterial adherence. This study analyzed in depth the manner by which heparin prevents the rise in adherence seen when the mucin is removed. Pretreatment of bacteria with heparin had no effect on adherence, whereas pretreatment of the bladder with heparin inhibited adherence. To corroborate our impression that the heparin was coating the transitional cells, [3H]heparin was added to bladders after removal of mucin. Autoradiography revealed the heparin to be adherent to the surface of the transitional cells.
Molecular characterization of plasmids from virulent and spontaneously occurring avirulent colonial variants of Shigella flexneri
Authors: Kopecko D J , Holcombe J , Formal S B
Published: January 2020

Spontaneous transition of Shigella flexneri from T- to O-type colonies with concomitant loss of virulence dose not appear to be accompanied by a change in any of the four plasmic species found in the virulent parent.
Humoral response to experimental petriellidiosis
Authors: Lupan D M , Cazin J
Published: January 2020

The humoral antibody response elicited by experimental infection with Petriellidium boydii and Monosporium apiospermum was studied. The variables of fungus strain, route of inoculation, and concentration of inoculum were examined. Viable spores from three strains of P. boydii and from three strains of M. apiospermum were inoculated intravenously into mice. Serum specimens were tested for antibody by the microtiter indirect hemagglutination assay. At 4 weeks after infection, the percentage of positive specimens among survivortically related either to the incidence of positive specimens or to the magnitude of the humoral response. Mice inoculated by either the subcutaneous or the intramuscular route with viable or killed spores from M. apiospermum 813 developed antibody. The mean antibody titer was greater in those animals receiving viable spores, and the magnitude of the humoral response was dose dependent. Animals inoculated intravenously with comparable inocula of the same strain developed similar levels of antibody. However, cultural studies of infected mice showed chronic infection only after intravenous inoculation. The kidney was the organ most consistently involved.
Capsular K1 polysaccharide of Escherichia coli: relationship to virulence in newborn rats and resistance to phagocytosis
Authors: Bortolussi R , Ferrieri P , Björkstén B , Quie P G
Published: January 2020

The virulence of Escherichia coli strains for newborn rats was related to opsonic requirements of the strains, sensitivity to the bactericidal activity of serum, and K1 capsular polysaccharide content. K1 E. coli strains were more virulent than non-K1 strains after intraperitoneal injection in newborn rats (P less than 0.05) and were more resistant to phagocytosis than non-K1 strains when the classical complement pathway was blocked with Mg-ethyleneglycoltetraacetic acid (P less than 0.0005). Sensitivity to the bactericidal activity of serum was similar among K1 and non-K1 E. coli strains. Two groups of K1 E. coli strains were defined on the basis of opsonic requirements. Group I strains were efficiently opsonized by the alternative complement pathway, while group II strains required the classical complement pathway for opsonization. Group I strains had less detectable K1 polysaccharide in the washed whole cell fraction than group II strains (10.3 versus 18.9 microgram of K1 polysaccharide per 10(10) colony-forming units) and were less virulent than group II strains (mortality, 44 versus 77%, P less than 0.05). The K1 capsular polysaccharide appears to play an important role in determining virulence in newborn rats and opsonic requirements of these strains, but does not contribute to the sensitivity of strains to the bactericidal activity of serum.
Lactoperoxidase binding to streptococci
Authors: Pruitt K M , Adamson M , Arnold R
Published: January 2020

There have been conflicting reports regarding the binding of lactoperoxidase to bacterial cell surfaces. We describe here the effects of cell-bound lactoperoxidase on acid production by suspensions of Streptococcus mutans (NCTC 10449) in the presence of hydrogen peroxide and thiocyanate. Saline suspensions of log-phase bacteria were treated with 0.1 mg of lactoperoxidase per ml and were then washed thoroughly. The addition of hydrogen peroxide and thiocyanate markedly reduced the acid production of these lactoperoxidase-treated bacteria but had no effect on the acid production of untreated controls. After a 3-h incubation in saline, the lactoperoxidase-treated bacteria produced acid in the presence of hydrogen peroxide and thiocyanate at the same rate as untreated bacteria. These observations suggest that lactoperoxidase is initially bound to the cell surface in an enzymatically active form at a concentration sufficient to inhibit acid production. The lactoperoxidase is slowly degraded or desorbed as the bacteria stand in saline suspension.
Structure and serological specificity of the K13-antigenic polysaccharide (K13 antigen) of urinary tract-infective Escherichia coli
Authors: Vann W F , Jann K
Published: January 2020

The primary structure of the K13-antigenic polysaccharide (K13 antigen) of Escherichia coli O6:K13:H1 was elucidated by composition, periodate oxidation, Smith degradation, and methylation analysis. The polysaccharide consists of a repeating sequence of 3-linked ribofuranose and 7-linked 3-deoxymannooctulosonic acid (KDO). About 50% of the KDO residues are O-acetylated at position 4 or 5. Measurement of the optical rotary dispersion indicated that in aqueous solution the K13 polysaccharide assumes a secondary structure in which the carboxyl groups of KDO are engaged. The serological specificity of the K13 polysaccharide is expressed through KDO and its O-acetyl substituent, the ribose unit being antigenically silent. There are two populations of anti-K13 antibodies one directed against the charged region of the KDO and the other against the O-acetyl groups.
Essential dependence of smooth surface caries on, and augmentation of fissure caries by, sucrose and Streptococcus mutans infection
Authors: Tanzer J M
Published: January 2020

Streptococcus mutans-free Osborne-Mendel rats were used to study the ability of well-characterized S. mutans strains of Bratthall serotypes c, d, and E to form plaque and cause caries when the animals consumed either sucrose- or glucose-containing diets. All of the serotype representatives successfully infected, colonized, and emerged in the oral ecology of animals, independent of the carbohydrate supplementation of the diet. However, the sucrose-containing diet supported higher percentages of S. mutans of all the serotypes in the plaque and greater amounts of plaque on the teeth. Smooth surface caries was essentially S. mutans dependent and sucrose dependent; fissure caries, although it was neither dependent on S. mutans infection nor sucrose consumption, was augmented by both. This sucrose-associated emergence of all three serotype representatives in the plaque flora and their virulence in the production of caries can be ascribed to their production of alkali-solible alpha-(1 yields 3)-rich glucans from sucrose.
Characterization of the Antigenic Determinants of Cholera Toxin Subunits
Authors: Markel Daiel E. , Hejtmancik Kelly E. , Peterson Johnny W. , Martin Frank B. , Kurosky Alexander
Published: January 2020

The antigenic specificity of purified preparations of A subunit, B subunit, α chain, and γ chain of cholera toxin was studied by double immunodiffusion and radioimmunoassay with antisera produced in rabbits and mice. Rabbits immunized with A subunit produced serum antibodies which were capable of binding radiolabeled A subunit, α chain, and B subunit. Rabbits immunized with α chain produced serum antibodies that would bind radiolabeled α chain and A subunit. Rabbits immunized with the B subunit produced serum antibodies monospecific for the B subunit. The γ chain did not elicit measurable antibodies in rabbits or mice as evidenced by radioimmunoassay or double immunodiffusion. A sensitive competitive radioimmunoassay was developed in which the B subunit could inhibit binding of radiolabeled A subunit and α chain with either antisera prepared against A subunit or α chain. Neither the A subunit nor the α chain could inhibit binding of B subunit with the antiserum prepared against B subunit. In addition, selected elution fractions obtained during A- and B-subunit purification were used to immunize groups of mice. Mice responded to immunization with the elution fractions of A subunit by producing anti-A-subunit and anti-B-subunit serum antibody responses, whereas mice immunized with elution fractions of B subunit produced only antibodies specific for the B subunit. An equimolar amount of the two resulting protein peaks was used to immunize two groups of rabbits. Rabbits immunized with A subunit, produced a serum anti-B subunit response equal to that of rabbits immunized with the B subunit. Rabbits immunized with equimolar concentrations of A and B subunits were observed to be equally protected against intestinal loop challenge with
Vibrio cholerae
Inaba V86. The A subunit, not the B subunit, was biologically active when tested by the S49 mouse lymphosarcoma cell test. These studies provide additional evidence supporting the hypothesis that the A subunit, specifically of α chain, of cholera toxin contains antigenic determinants in common with the B subunit.
Mitogenic Effects of Bacterial Cell Walls, Their Fragments, and Related Synthetic Compounds on Thymocytes and Splenocytes of Guinea Pigs
Authors: Takada Haruhiko , Tsujimoto Masachika , Kotani Shozo , Kusumoto Shoichi , Inage Masaru , Shiba Tetsuo , Nagao Shigeki , Yano Ikuya , Kawata Shigeo , Yokogawa Kanae
Published: January 2020

Stimulation of [
3
H]thymidine incorporation of thymocytes and splenocytes from guinea pigs by various bacterial cell walls and their peptidoglycans, by enzymatic digests, and by synthetic muramyl dipeptides was studied as an indication of mitogenic activity. Cell wall and peptidoglycan preparations, isolated from 19 strains belonging to 18 different species, definitely increased [
3
H]thymidine incorporation of thymocytes as well as splenocytes, regardless of mycolic acid contents as a non-peptidoglycan component. Both the cell walls from
Nocardia corynebacteriodes
(containing mycolic acids) and those from
Streptomyces gardneri
(lacking mycolic acids) showed far stronger mitogenic activities on splenocytes than other cell walls (stimulation index, 25 to 30). Furthermore, water-soluble enzymatic digests, notably the endopeptidase digests, which generally were greater in degree of polymerization of peptidoglycan subunits than the glycosidase digests obtained from representative cell walls, were found to have as distinct a stimulating activity on splenocytes as the original cell walls. In contrast, solubilization of the cell walls by enzymes, irrespective of endopeptidases or glycosidases, was accompanied by disappearance of the mitogenic activity on thymocytes. On the other hand, studies with synthetic 6-
O
-acyl-MurNAc-
l
-Ala-
d
-isoGln preparations (6-
O
-acyl-MDPs) revealed that 6-
O
-stearoyl-MDP and 6-
O
-(2-tetradecylhexadecanoyl)-MDP, unlike MDP, had distinct mitogenic activity on thymocytes, whereas their activity on splenocytes was rather weaker than MDP itself. The findings presented here suggest that MDP is the minimal structure for the mitogenic activities of bacterial cell walls on guinea pig splenocytes, but that MDP, though distinctively active by itself, requires a polymerized form to exert effectively its inherent stimulating activities on splenocytes. On the other hand, on thymocytes, MDP, unless it takes a particular form or has appropriate additive groups, cannot exert its mitogenic activities.
In vitro studies of dental plaque formation: adsorption of oral streptococci to hydroxyaptite
Authors: Appelbaum B , Golub E , Holt S C , Rosan B
Published: January 2020

A mixture of saliva-coated hydroxyapatite beads and radioactively labeled bacteria has been employed as an in vitro model for the initial phase of dental plaque formation. Adsorption in this model can be expressed by the Langmuir adsorption isotherm, and the adherence of oral streptococci can be expressed as the product of the affinity constant (Ka) and the number of binding sites (N), KaN. With this approach, Streptococcus sanguis serotype 1 strains adhered better (KaN = [187 +/- 72] X 10(-2)) than serotype 2 strains (KaN = [97 +/- 84] X 10(-2)); a t test showed this difference to be statistically significant to the 99.99% confidence level. Strains of S. mitis, S. mutans, and S. salivarius did not appear to adhere as well. To analyze the bacterial receptors involved in adherence, competition studies in which increasing quantities of unlabeled bacteria were added to a fixed quantity (4 X 10(9) cells per ml) of 3H-labeled serotype 1, reference strain S. sanguis G9B, were performed. These studies indicated that the type 1 strains competed for the same, or closely related, binding sites. Competition studies using serotype 2 S. sanguis strains resulted in an increased binding of reference strain G9B to hydroxyapatite. Scanning electron microscopy indicated this effect was due to the formation of localized aggregations of bacteria, presumably representing the two bacterial types. The results of competition studies with S. mitis were variable, and several strains of other oral bacteria showed little or no competition.
Effect of visceral leishmaniasis on congenitally athymic mice
Authors: Smrkovski L L , Larson C L , Reed S G
Published: January 2020

Congenitally athymic mice were more susceptible to challenge with amastigotes of Leishmania donovani than were their thymus-intact littermates. This increased susceptibility correlated with a lack of Arthus and delayed-type responses when animals were skin tested with leishmanial antigen.
Intracellular localization of the dermonecrotic toxin of Bordetella pertussis
Authors: Cowell J L , Hewlett E L , Manclark C R
Published: January 2020

Localization of the heat-labile dermonecrotic toxin of Bordetella pertussis strain 114 grown in chemically defined Stainer-Scholte medium was studied by using skin reaction in 4-day-old suckling mice as the assay for toxin. Through log phase and into stationary phase of growth the toxin was cell associated and not detected in the culture supernatant. Only about 4% of the activity present in a suspension of lysed cells was detected in a suspension of whole cells, and the dermonecrotic activity was not released by subjecting whole cells to osmotic shock, a procedure that releases proteins from the periplasmic space of many gram-negative bacteria. After cell lysis and preparation of soluble and membrane fractions, 73 to 80% of the activity in the cell lysate was recovered in the soluble fraction, with only 3 to 6% present in a membrane fraction. Further evidence for the intracellular cytoplasmic localization of the dermonecrotic toxin was the insensitivity of the toxin to trypsin treatment of whole cells. Treatment of whole cells with trypsin (80 micrograms/ml) for 20 min at 37 degrees C did not decrease dermonecrotic or malate dehydrogenase activities, but did inhibit more than 95% of the extra-cytoplasmic adenylate cyclase activity. Identical trypsin treatment of a cell lysate decreased all the above activities by more than 90%.
In vitro replication of infectious bursal disease virus in established lymphoid cell lines and chicken B lymphocytes
Authors: Hirai K , Calnek B W
Published: January 2020

The in vitro susceptibility of chicken lymphocytes to a wild strains of infectious bursal disease virus was investigated by using immunofluorescence and virus assays as infection criteria. A variety of Marek's disease lymphoblastoid cell lines, all of thymus (T-cell) origin, were refractory to virus exposure. However, a bursa (B-cell)-derived lymphoblastoid cell line from an avian leukosis virus-induced tumor was highly susceptible. Viral antigen appeared in the cytoplasm of 20 to 30% of the cells, and large amounts of cell-free virus were released, with maximum yields occurring by 3 days postinfeciton. The virus also replicated in a small percentage of normal lymphocytes prepared from lymphoid tissues and peripheral blood of chickens. Pretreatment of the lymphocytes, with heat-inactivated anti-B-cell serum or with antiserum against fowl immunoglobulin M before inoculating them with the virus blocked the virus infection; no blocking occurred with anti-T-cell serum or with specific antiserum against fowl immunoglobulin G or immunoglobulin A. This suggests that surface immunoglobulin M-bearing B-lymphocytes were the target cells for infection.
Natural Killing of Herpes Simplex Virus Type 1-Infected Target Cells: Normal Human Responses and Influence of Antiviral Antibody
Authors: Ching Clara , Lopez Carlos
Published: January 2020

Studies of a mouse model of genetic resistance to herpes simplex virus type 1 (HSV-1) indicate that the marrow-dependent effector cell of allogeneic resistance plays an important role in natural resistance to this virus infection. Since the marrow-dependent effector cell appears to be closely related to the natural killer (NK) cells, an NK assay with HSV-1-infected fibroblasts [NK(HSV-1)] has been developed to study this resistance mechanism in humans. Incubation of effector and target cells for 12 to 14 h gave the greatest percent specific release (%SR) and kept spontaneous
51
Cr release from infected target cells below 35%. Patients with Bruton's agammaglobulinemia demonstrated significant kill indicating antiviral antibody was not necessary. Seropositive individuals gave a 9% greater%SR than seronegative individuals. Depletion of B-cells consistently diminished NK (HSV-1) for seropositive individuals and augmented kill for seronegative individuals. Although antiviral antibody produced in culture may contribute to NK (HSV-1), depletion of B-cells allowed quantitation of NK (HSV-1) to the exclusion of most of the antibody-dependent kill. The NK cells detected by this assay showed many of the properties reported for NK cells with K562 targets. Two patients with severe herpesvirus infections demonstrated NK (HSV-1) responses greater than 2 standard deviations below the normal mean. Since normal individuals with virus infections have higher rather than lower natural kill, the low NK (HSV-1) may reflect their susceptibility to the virus infection.