bluuebunny/crossref_metadata_2025 huggingface dataset:
Bactericidal activity of fractionated granule contents from human polymorphonuclear leukocytes: antagonism of granule cationic proteins by lipopolysaccharide
Authors: Modrzakowski M C , Spitznagel J K
Published: January 2020

Granule extracts from human polymorphonuclear leukocytes (PMN) were prepared with 0.2 M (pH 4.0) acetate. A fraction (valley AB) with distinctive bactericidal activity against cell wall mutants of Salmonella typhimurium LT-2 was obtained after fractionation of the granule extracts by Sephadex G-100 column chromatography. The smooth parent LT-2 strain was less sensitive to the bactericidal action. Susceptibility of the rough mutants to bactericidal action increased as sugar residues decreased in the lipopolysaccharide (LPS) (Re greater than Rd2 greater than Rd1 greater than Rc greater than Ra). Cationic protein(s) responsible for bactericidal activity could be selectively removed from the fraction by absorption with whole LT-2 cells or purified LPS. Loss of cationic protein species was confirmed by cationic polyacrylamide gel electrophoresis. Purified LPS from LT-2 or the deep rough mutant TA2168 inhibited the antimicrobial activity of the killing fraction in in vitro assays. A minor protein species (vAB1) from the valley AB fraction had an apparent molecular weight of 36,000 to 37,000 and represented a major bactericidal activity of the fraction. Small amounts of the isolated vAB1 protein were bactericidal for the smooth parent LT-2 strain.
Mechanism of action of Yersinia enterocolitica enterotoxin
Authors: Robins-Browne R M , Still C S , Miliotis M D , Koornhof H J
Published: January 2020

Enterotoxin derived from three clinical isolates of Yersinia enterocolitica was compared with the heat-stable enterotoxin of Escherichia coli. Both toxins were biologically active in infant mice examined at 2 h and in ligated rabbit ileal loops at 6 h. Neither substance, however, produced changes in ligated ileal loops at 18 h or in Chinese hamster ovary or Y1 adrenal tissue cultures. In addition, both Y. enterocolitica enterotoxin concentrated approximately 20 times by ammonium sulfate precipitation and ultrafiltration and a similarly prepared sample of E. coli heat-stable enterotoxin stimulated the activity of guanylate cyclase but not that of adenylate cyclase in infant mouse intestine. These findings suggest that the role of enterotoxin in the pathogenesis of intestinal Y.enterocolitica infection may be similar to that of heat-stable enterotoxin in E. coli diarrhea.
Isolation and development of a reticuloendotheliosis virus-transformed lymphoblastoid cell line from chicken spleen cells
Authors: Keller L H , Rufner R , Sevoian M
Published: January 2020

The establishment and characterization of a reticuloendotheliosis virus (strain T)-transformed lymphoblastoid cell line, designated TV-1, was reported. These cells, isolated from the spleen of a moribund chick infected with reticuloendotheliosis virus, were maintained in suspension culture for over 74 weeks at a stable generation time of 15 h. The cells were found to carry a female karyotype. Both TV-1 cells and cell-free TV-1 culture supernatant produced lesions and mortality patterns in chicks which were identical to those caused by reticuloendotheliosis virus (strain T) infection. Examination of TV-1 cells by electron microscope revealed the presence of C-type virions budding from the plasma membrane. Cytotoxicity assays and fluorescent antibody tests indicated the presence of B-cell determinants on the TV-1 cell surface membrane.
Evaluation of a new polyvalent Pseudomonas vaccine in respiratory infections
Authors: Pennington J E , Miler J J
Published: January 2020

A new polyvalent, cell wall extract, Pseudomonas aeruginosa vaccine (PEV-01), was evaluated by using a guinea pig model of experimental Pseudomonas pneumonia. Guinea pigs routinely developed fourfold rises in serum hemagglutinating Pseudomonas antibodies after four vaccine injections given over 2 weeks. Vaccinated animals survived an intratracheal Pseudomonas challenge (1 X 10(8) colony-forming units) significantly better (13 of 14 survived) than did a control group (5 of 14 survived) (P less than 0.01). Clearance of viable Pseudomonas from lung tissue was significantly better in vaccinees than controls at both 3 h (P less than 0.02) and 6 h (P less than 0.05) after infection. Both gross and histological examinations of lung tissue revealed less pulmonary tissue damage in vaccinated animals following Pseudomonas infection. Thus, PEV-01 Pseudomonas vaccine appears capable of eliciting a specific protective response in the guinea pig respiratory tract.
Immunotherapy of guinea pigs with a transplanted hepatoma: comparison of intralesionally administered killed BCG cells and BCG cell walls
Authors: Yarkoni E , Rapp H J
Published: January 2020

Heat-killed whole BCG cells (KC) and BCG cell walls (CW) were each tested in emulsified form for their potency to cause regression of a transplanted guinea pig hepatoma. On a weight basis, KC were at least as effective as CW in causing tumor regression and elimination of microscopic lymph node metastasis, and they, as well as purified protein derivative of mycobacteria, provoked delayed cutaneous hypersensitivity reactions in animals immunized with CW or with KC. On a weight basis, KC were as active as CW in eliciting delayed cutaneous hypersensitivity in sensitized guinea pigs whether the animals were immunized with CW or with KC. In unimmunized animals the inflammatory response to intradermally administered KC was similar to that induced by CW. Because KC are easier to prepare than CW, it is suggested that whole killed BCG might be used instead of CW in clinical trials of cancer treatment requiring administration of nonliving mycobacteria.
Inhibition by human serum of lymphocyte proliferation stimulated by purified protein derivative of tuberculin and bacillus Calmette-Guérin
Authors: Herman-Brand R , Sultzer B M
Published: January 2020

The addition of normal human serum to murine lymphocyte cultures consistently depressed mitogen-induced transformation, as measured by deoxyribonucleic acid synthesis. Stimulation by the B-cell mitogens purified protein derivative-tuberculin, bacillus Calmette-Guérin, and lipopolysaccharide was consistently affected, but there was no inhibition of T-cells when human serum was added to concanavalin A-stimulated cultures. The inhibitory effects were not due to cytotoxic factors for B-lymphocytes or to specific antibodies in serum directed against the mitogens. Analogous results were found with guinea pig serum. Contact of the lymphocytes with the serum within the first 24 h of culture was necessary for inhibition.
Inhibition of translocation of viable Escherichia coli from the gastrointestinal tract of mice by bacterial antagonism
Authors: Berg R D , Owens W E
Published: January 2020

The incidence of translocation of viable Escherichia coli C25 from the gastrointestinal tract to the mesenteric lymph nodes was compared in gnotobiotic mice colonized with only E. coli C25 and in gnotobiotic mice colonized with E. coli C25 plus the whole cecal flora from specific pathogen-free mice. The population levels of E. coli C25 in the ilea and ceca of these mice also were compared. E. coli C25 maintained high population levels in the gastrointestinal tracts of the monoassociated gnotobiotes, and the incidence of translocation to the mesenteric lymph nodes was 100%. The gastrointestinal population levels of E. coli C25 were reduced drastically in the gnotobiotes associated with both E. coli C25 and a cecal flora with concomitant reduction in the incidence of translocation of E. coli C25 from 100 to 0%. A decrease in the numbers of viable E. coli C25 per mesenteric lymph node also accompanied the decrease in C. coli C25 population levels in the gastrointestinal tracts of these mice. Thus, high population levels of E. coli C25 in the gastrointestinal tracts of monoassociated gnotobiotic mice appear to promote translocation of viable E. coli C25 to the mesenteric lymph nodes. Bacterial antagonism of E. coli population levels in conventional mice, therefore, could be one mechanism whereby viable E. coli are confined to the gastrointestinal tract.
Modified polyriboinosinic-polyribocytidylic acid complex: sustained interferonemia and its physiological associates in humans
Authors: Champney K J , Levine D P , Levy H B , Lerner A M
Published: January 2020

Fourteen patients with severe viral illnesses were given intravenous infusions of a modified interferon inducer, polyriboinosinic-polyribocytidylic acid-poly-L-lysine complexed with carboxymethylcellulose [poly)I:C.LC)], during a phase 1 clinical trial. The first eight patients received 0.15 to 0.30 mg of poly(I:C.LC) per kg of body weight daily for 5 consecutive days, and another received two courses separated by 1 week. A second group of five patients was given single intravenous infusions of 0.10 to 0.15 mg of poly(I:C.LC) per kg. Interferon was detectable in the serum 8 to 16 h after injection. Titers ranged from 15 to 800 U/ml and varied directly with the dose of poly(I:C.LC). Interferonemias persisted for 12 to 48 h. In patients receiving 5-day courses of poly(I:C.LC), lower levels of serum interferon (0 to 160 U/ml) occurred on days 2 through 5, characteristic of a hyporesponsive state. An exception was a 69-year-old patient with disseminated varicella zoster, multiple myeloma, and renal insufficiency whose serum contained 3,150 U of interferon per ml on day 3 of 0.3 mg of poly(I:C.LC) per kg. Fever (39 to 40.5 degrees C, rectally; 13 of the 14 patients) peaked 3 to 8 h after completion of infusions. Other toxic effects included lymphopenia (10 of the 14 patients), hypotensive episodes (7 of the 14 patients), and minor elevations of serum glutamicoxalacetic transaminase and lactic dehydrogenase.
Serum antibody prevents lethal murine influenza pneumonitis but not tracheitis
Authors: Ramphal R , Cogliano R C , Shands J W , Small P A
Published: January 2020

This paper reports studies showing the effects of serum antibody upon influenza infection at two different sites: the trachea and lung. Tracheal desquamation, pulmonary consolidation, death, and virus shedding were examined after infection of mice with a lethal A/Port Chalmers/1/73 (H3N2) influenza virus. Immune serum administered intraperitoneally before infection prevented death and pulmonary consolidation and also significantly lowered lung virus shedding as compared with controls receiving normal serum. However, this protection did not extend to the ciliated epithelium of the trachea because serum antibody did not prevent desquamation of the trachea or significantly decrease viral yield from the trachea. These results indicate that serum antibody is protective against severe pulmonary parenchymal disease but not for disease of the ciliated epithelium.
Sites that bind polymerized albumin on hepatitis B surface antigen particles: detection by radioimmunoassay
Authors: Hansson B G , Purcell R H
Published: January 2020

Antibodies to polymerized human albumin (poly-HSA) could not be detected by using sensitive methods (enzyme-linked immunosorbent assay and radioimmunoprecipitation) in sera from chronic carriers of hepatitis B surface antigen (HBsAg) or in serial bleedings from one chimpanzee infected with type A hepatitis virus and one infected with non-A, non-B hepatitis virus. By a solid-phase radioimmunoassay, receptor sites for poly-HSA could be detected on HBsAg particles from sera containing either hepatitis B "e" antigen (HBeAg) or anti-HBe. Blocking experiments showed that monomeric HSA did not bind to this receptor. In general, the HBsAg particles from sera with HBeAg had more poly-HSA receptor sites or relatively more particles carrying this receptor compared with HBsAg from sera with anti-HBe. Microtiter plates coated with poly-HSA bound HBsAg from sera containing HBeAg with greater efficiency than did anti-HBs coupled to a solid phase (Ausria II beads), whereas with sera positive for anti-HBe, the two assays were equally sensitive. Decreased ability of HBsAg to bind to poly-HSA was seen in some sera which had been stored for a few years at 4 degrees C, whereas the binding to anti-HBs was unaffected. It is possible that polymers of albumin on the surface of hepatocytes could function as receptors for hepatitis B virus.
Analysis of the Adhesion Step in the Herpes Simplex Virus Antibody-Dependent Cellular Cytotoxicity System
Authors: Romano Thomas J. , Shore Steven L.
Published: January 2020

The lysis of herpes simplex virus-infected tissue culture cells by antibody-dependent cellular cytotoxicity (ADCC) requires a preliminary step in which effector cells adhere to the immunoglobulin G antibody-coated targets. To study the adhesion step, we made use of two observations: (i) some of the mononuclear cells in human blood form rosettes with antibody-coated target cells, and (ii) most ADCC effector cells can be removed by allowing mononuclear cells to adhere to monolayers of antibody-sensitized tissue culture cells. The effect of various experimental conditions on the adhesion step was assessed in ADCC cultures both at unit gravity and after centrifugation. At unit gravity both rosette formation and monolayer adhesion were partially reduced at 4°C as compared to 37°C. Both were also partially inhibited in glucose-free medium containing sodium azide and 2-deoxyglucose but were unaffected in glucose-free medium containing only one of these energy inhibitors. In contrast, after centrifugation neither reaction was inhibited at 4°C or in glucose-free medium with sodium azide and 2-deoxyglucose. Cytochalasin B but not colchicine suppressed both reactions. Inhibition by cytochalasin B could not be reversed by centrifugation. Both reactions were independent of extracellular Ca
2+
and Mg
2+
and were unaffected by rendering mononuclear cells cytotoxically inactive by brief heat shock. These findings indicate that the adhesion step in ADCC directed against virus-infected or uninfected tissue culture cells is only modestly dependent on effector cell energy generation, that centrifugation greatly reduces this dependence, and that microfilaments but not microtubules are necessary. The modest ambient temperature and energy requirements, independence of extracellular divalent cations, lack of sensitivity to colchicine, and relative resistance to supraphysiological temperature serve to distinguish the adhesion step from the lytic step in ADCC.
Live Victoria/75-
ts
-1[E] Influenza A Virus Vaccines in Adult Volunteers: Role of Hemagglutinin Immunity in Protection Against Illness and Infection Caused by Influenza A Virus
Authors: Douglas R. Gordon , Markoff Lewis J. , Murphy Brian R. , Chanock Robert M. , Betts Robert F. , Hayden Frederick G. , Levine Myron M. , Van Blerk Gillian A. , Sotman Steven B. , Nalin David R.
Published: January 2020

To explore the relationship between neuraminidase immunity and the degree of attenuatíon of live influenza A virus vaccines, a comparative evaluation of three Victoria/75-
ts
-1[E] (Vic/75-
ts
-1[E]) recombinant viruses in serum hemagglutination-inhibiting-negative (titer, ≤1:8) adult volunteers was performed. These three
ts
-1[E] viruses had a similar restriction of replication at 38°C in vitro, and each possessed the two attenuating genes of the
ts
-1[E] donor strain (13). However, Vic/75-
ts
-1[E] recombinants 81 and 113 possessed both Vic/75 hemagglutinin (H3
75
) and Vic/75 neuraminidase (N2
75
), whereas Vic/75-
ts
-1[E] recombinant 67 had Vic/75 hemagglutinin but the N2
65
neuraminidase. Vic/75-
ts
-1[E] recombinant 67 was significantly more attenuated than Vic/75-
ts
-1[E] recombinants 81 and 113 in that fewer local and systemic signs and symptoms of illness were observed in those volunteers who received clone 67. These findings were consistent with our previous observations which suggested that the following two factors contribute to the attenuation of
ts
-1[E] vaccine strains in adults: (i) the attenuating effect of the two
ts
-1[E] genes and (ii) the neuraminidase immunity of the host. Vic/75-
ts
-1[E] recombinant clone 67 vaccinees developed an immunological response to the H3
75
hemagglutinin in the absence of a response to the N2
75
neuraminidase. To assess the role that anti-hemagglutinin immunity induced by an attenuated live virus vaccine plays in resistance to influenza A virus, vaccinees who received recombinant 67 were challenged with Vic/75 wild-type virus, and their responses were compared with those of Vic/75-
ts
-1[E] vaccinees who received recombinant 81 or 113. Each of the three groups of
ts
-1[E] vaccinees was significantly protected against illness induced by wild-type virus infection, although resistance was not complete. However, the clone 67 vaccinees were protected less against infection. The infection-permissive resistance induced by clone 67 resembled that previously described for inactivated neuraminidase-specific vaccines. These results suggested that a
ts
-1[E] recombinant that possessed the hemagglutinin of a new pandemic variant, the neuraminidase of the preceding subtype, and the two
ts
-1[E]
ts
genes would be satisfactorily attenuated for children and adults with neuraminidase immunity and could induce resistance to illness caused by the new pandemic wild-type influenza A virus.
Multiplication of Leishmania in human macrophages in vitro
Authors: Berman J D , Dwyer D M , Wyler D J
Published: January 2020

To facilitate in vitro studies of the immunology of human leishmaniasis, we developed a method of growing pathogenic Leishmania in human monocyte-derived macrophages. After 6 days of incubation, adherent mononuclear cells were infected with Leishmania donovani amastigotes obtained from infected hamster spleen cells or with L. tropica amastigotes obtained from infected BALB/c tissue mouse footpad. Forty-eight percent of the macrophages were initially infected, with a mean of 3.0 amastigotes per infected macrophage. After 6 days of incubation, 59% of macrophages were infected and contained 8.8 amastigotes per infected macrophage, representing 2.9-fold multiplication. Electron microscopy revealed the presence of dividing parasites within phagolysosomes. These observations indicate that Leishmania survive and multiply within human monocyte-derived macrophages despite fusion of secondary lysosomes with the parasitophorous vacuole.
Nature of the fructan of Streptococcus mutans OMZ 176
Authors: Corrigan A J , Robyt J F
Published: January 2020

The fructan of Streptococcus mutans OMZ 176 was shown to have a levan structure by comparing the chromatographic mobilities of the saccharides produced by partial acid hydrolysis of ghe fructan and known levan and inulin. This was confirmed by using concanavalin A as a lectin in a double-diffusion gel technique.
Suppression of lymphocyte response to concanavalin A by mucopolysaccharide material from Treponema pallidum-infected rabbits
Authors: Bey R F , Johnson R C , Fitzgerald T J
Published: January 2020

The testicular fluid and serum from rabbits infected intratesticularly with Treponema pallidum inhibited the mitogenic response of normal rabbit peripheral blood lymphocytes to concanavalin A. Mucopolysaccharide material present in the testicular fluid and serum was associated with the lymphocyte-inhibitory activity. Degradation of the mucopolysaccharide material with hyaluronidase resulted in the loss of the inhibitory activity of testicular fluid and serum of T. pallidu-infected rabbits.
Mannose-contaminating agglutinin for Actinomyces viscosus and Actinomyces naeslundii
Authors: Ellen R P , Leung W L , Fillery E D , Grove D A
Published: January 2020

Rapid agglutination of Actinomyces viscosus and Actinomyces naeslundii cells by D-mannose solutions was observed during studies of their attachment to mammalian cells in vitro. The specificity of the agglutination reaction was studied by slide agglutination tests and by measuring the rate of decrease in optical density of bacterial phosphate buffer suspensions caused by the setting of bacterial aggregates. Actinomyces cells were agglutinated by protein-containing mannose solutions of several chemical suppliers. Solutions of sugars other than D-mannose and solutions of mannitol and mannan all failed to agglutinate A. viscsus and A. naeslundii. "Mannose-enhanced" agglutination was impaired by boiling or autoclaving the mannose but was not affected by heating the bacteria, the presence of chloramphenicol, running the assay in the cold, or incorporating any of several commercially purchased sugars in the reaction mixture. During these hapten inhibition experiments, only 6-deoxy-L-talcose-containing extracts of an A. viscosus strain retarded the rate of mannose-enhanced agglutination. Protein-containing fractions of D-mannose mother liquors also agglutinated cells of A. viscosus and A. naeslundii. Other species of oral gram-positive rods were not agglutinated by mannose solutions. Together the data indicate that plant seed-derived D-mannose contains a protein-associated agglutinin for A. viscosus and A. naeslundii which may function via a "lectin-like" selective affinity for the unique cell wall sugar 6-deoxy-L-talose.
Chemotaxigenesis and activation of the alternative complement pathway by encapsulated and non-encapsulated Cryptococcus neoformans
Authors: Laxalt K A , Kozel T R
Published: January 2020

In the presence of serum, whole cells of encapsulated and non-encapsulated Cryptococcus neoformans generated a chemotactic response by neutrophils. Heat inactivation of serum ablated all chemotactic activity. Cryptococcal polysaccharide was not chemotaxigenic. Assays for alternative complement pathway activation such as depletion of alternative complement pathway factor B or electrophoretic conversion of factor B closely paralleled chemotaxis assays. Cells of encapsulated and non-encapsulated C. neoformans activated the alternative complement pathway, whereas cryptococcal polysaccharide was inactive. Failure of the capsular material to activate the alternative pathway was not due to serotype specificity because polysaccharide of several serotypes failed to achieve activation. The results suggest that chemotaxigenesis and alternative complement pathway activation are functions of the yeast cell wall. The results support our proposal that the cryptococcal capsul does not prevent potential opsonins from reaching binding and activation sites at the yeast cell wall or the release of biologically active soluble cleavage products into the surrounding medium; however, cell wall-bound cleavage products remain bound to the cell wall beneath the capsule. Therefore, they are unable to participate as opsonins in phagocytosis.
Reinterpretation of the Dick test: role of group A streptococcal pyrogenic exotoxin
Authors: Schlievert P M , Bettin K M , Watson D W
Published: January 2020

Because of the association of the group A streptococcal pyrogenic exotoxins (SPEs) with erythrogenic toxin used in the classical Dick test, the involvement of the SPEs in production of erythematous skin reactions was assessed. Unless they had been presensitized, young adult rabbits failed to show skin reactions after intracutaneous challenged with SPEs. Rabbits presensitized to purified protein derivative exhibited enhanced skin reactivity when given purified protein derivative plus SPE C; the enhancement was neutralized by antiserum to SPE C. Rabbits sensitized to bovine serum albumin showed extensive red rash development resembling scarlet fever rashes when given bovine serum albumin containing SPE C. Desquamation occurred 5 to 10 days after injection. Animals sensitized to one SPE type showed enhanced skin reactivity to challenge with homologous or heterologous SPE types, indicating the presence of a cross-reactive determinant within the SPE molecules. Repeated challenge of SPE-sensitized animals with homologous toxin resulted in concomitant antitoxin production with reduction of the enhanced skin reactivities, until typical delayed-hypersensitivity skin reactions remained. The data indicate that, in addition to the toxic reaction previously described, SPEs enhance Arthus and delayed-hypersensitivity skin reactions. It follows that erythrogenic toxin represents the enhancement of acquired skin reactivity to streptococcal antigens by one or more SPE types. Therefore, the Dick test measures SPE-enhanced hypersensitivity to streptococcal products.
Human monocyte killing of Staphylococcus aureus: modulation by agonists of cyclic adenosine 3',5'-monophosphate and cyclic guanosine 3',5'-monophosphate
Authors: O'Dorisio M S , Vandenbark G R , LoBuglio A F
Published: January 2020

This study was designed to test whether cyclic nucleotides play a role in the regulation of bacterial killing by human monocytes. Agents were tested for their ability to activate monocyte adenylate or guanylate cyclase in cell-free preparations, to increase cyclic adenosine 3',5'-monophosphate (cAMP) or cyclic guanosine 3',5'-monophosphate (cGMP) in intact human monocytes, and to modulate monocyte-induced killing of Staphylococcus aureus in vitro. Prostaglandin E1 and cholera toxin activated monocyte adenylate cyclase and inhibited monocyte killing of S. aureus. An adenylate cyclase inhibitor, RMI 12330A, reversed the prostaglandin E1-mediated inhibition of bacterial killing, thus implicating cAMP as the intracellular mediator of this inhibition. In contrast, monocyte cGMP levels were increased 5- and 17-fold by 5-hydroxytryptamine and N-methyl-N' -nitro-N-nitrosoguanidine, respectively, but neither agent was effective in modulating monocyte bactericidal activity. Thus, modulation of bactericidal activity in human monocytes did not conform to the yin/yang theory of opposing actions by cAMP and cGMP, for although monocyte-mediated killing of S. aureus was inhibited by cAMP agonists, it was not enhanced by cGMP agonists.
Resistance of C58 mice to primary systemic herpes simplex virus infection: macrophage dependence and T-cell independence
Authors: Schlabach A J , Martinez D , Field A K , Tytell A A
Published: January 2020

The relative contribution of thymus-derived lymphocytes (T-cells) and of macrophages to resistance to primary infection with herpes simplex virus type 1 (HSV-1) was studied in C58 mice. Resistance was dependent on macrophage competence, but was relatively independent of T-lymphocyte competence. Although aging mice became progressively more deficient in functional T-cells, as demonstrated by a decreasing resistance to transplanted line Ib leukemia and by declining responses to T-cell nitogens (concanavalin A and phytohemagglutinin), their resistance to HSV-1 increased with increasing age. Moreover, in mice that were made selectively deficient in T-cells by the combination of adult thymectomy and treatment with anti-thymocyte serum, resistance to HSV-1 did not correlate spleen and mesenteric lymph nodes. However, selective reduction of macrophages by intraperitoneal injection of silica resulted in enhanced susceptibility to HSV-1. Furthermore, in vitro suppression of HSV-1 plaque formation in mouse embryo fibroblast cells was obtained by cocultivation of infected fibroblast monolayers with peritoneal macrophages, but not with splenic lymphocytes, from adult mice. Macrophages from weanling mice failed to suppress the development of plaques, indicating that the increase in resistance to HSV-1 with age is a result of increased macrophage competence.
Virulence of
Streptococcus mutans
: In Vivo Reversion of a Low-Virulence Mutant Results in Partial Displacement and Pathogenesis
Authors: Hirasawa Masatoma , Kiyono Hiroshi , Babb James L. , Shiota Tetsuo , Michalek Suzanne M. , McGhee Jerry R.
Published: January 2020

A mutant of
Streptococcus mutans
6715 wild type (WT), designated C4, has been shown previously to be defective in glucosyltransferase synthesis of insoluble glucan and to have low virulence in monoassociated gnotobiotic rats. The present investigation was concerned with the detection of WT-like variants of C4 in monoassociated rats, the supplantation of C4 by these WT-like organisms, and finally, the pathogenic potential of these WT-like organisms in gnotobiotic rats. In the first series of longitudinal studies with C4-monoassociated rats, WT-like organisms were detected at a low frequency (0.001%) in oral swab samples from only one of four cages of animals analyzed on day 7 after infection (age 27 days). The frequency of variants isolated from animals in the one cage increased, and by age 45 days these organisms represented approximately 1% of the mandibular plaque flora. After random redistribution of rats in the four cages (age 45 days), microbial analysis of oral swab samples (age 60 days) demonstrated the presence of variants in samples taken from rats in all four cages. The frequency of recoverable variants increased in older animals (age 90 days) and correlated with high caries activity. WT-like organisms were transmissible, since offspring (age 45 days) from these animals had high levels of variants as well as high caries activity. Similar results were obtained in a second longitudinal study; however, variants, although present in all four cages, were not detected until rats were 45 days old. All variant isolates exhibited morphological, biochemical, and in vivo virulence characteristics more similar to
S. mutans
6715 WT than to C4. In vitro mixing experiments with C4 and either WT or a selected variant suggested that C4 was rapidly displaced by WT organisms. The results of this investigation demonstrate that the glucosyltransferase-defective, low-virulence C4 reverts to virulent WT-like organisms in vivo which compete more favorably for smooth surfaces than C4. Subsequently, these variants reached significant numbers in plaque which correlated with increased dental caries.
Measles-specific antibodies in sera and cerebrospinal fluids of patients with multiple sclerosis
Authors: Hayes E C , Gollobin S D , Machamer C E , Westfall L K , Zweerink H J
Published: January 2020

Immunoprecipitation methods were used to analyze sera and cerebrospinal fluids from patients with multiple sclerosis for measles virus-specific antibodies. The sera contained antibodies against all virus antigens except the matrix polypeptide. Of the nine cerebrospinal fluids investigated, two contained undetectable levels of measles-specific antibodies, four contained antibodies against the nucleocapsid and another internal antigen, and three contained antibodies against the surface antigens as well as the internal antigens.
Role of specific cytotoxic lymphocytes in cellular immunity against murine cytomegalovirus
Authors: Ho M
Published: January 2020

Cytotoxic lymphocytes were generated in vitro against murine cytomegalovirus (MCMV)-infected cells by incubation with ultraviolet light-irradiated, infected fibroblasts. When passively transferred, they reduced virus titers in spleens of mice 1 day after infection with MCMV. Protection was abrogated by anti-theta serum and complement. Spleen cells from mice infected for 6 to 14 days protected mice better than cells from mice after infection for 1, 3, or 30 days. Protection by in vitro- and in vivo-generated cells was H-2K or H-2D restricted. Specific cytotoxic T lymphocytes are therefore present and operative during acute MCMV infection. However, MCMV infection inhibited the development of primary cytotoxic response against ectromelia virus. It also suppressed the ability of lymphocytes from mice with established memory for ectromelia to develop secondary cytotoxic cells in vitro, and it inhibited the development of memory cells for the cytotoxic response to ectromelia virus. In view of these data and the inability of animals recovering from MCMV infection to eliminate all infected cells, the cytotoxic response to MCMV may be qualitatively or quantitatively deficient.
Influence of anti-slime glycolipoprotein serum on the interaction between Pseudomonas aeruginosa and macrophages
Authors: Bartell P F , Krikszens A
Published: January 2020

Glycolipoprotein, a purified fraction of the exopolysaccharide slime of Pseudomonas aeruginosa, was identified as responsible for a number of the biological activities of viable cells, including toxicity and immunogenicity capable of stimulating protective antibody against the lethal effects of viable cells. Antiserum against glycolipoprotein also mediated the phagocytosis and subsequent killing of viable P. aeruginosa by unstimulated mouse peritoneal macrophages. In the absence of anti-glycolipoprotein serum, macrophages did not significantly reduce the number of bacteria. The presence of complement in the experimental mixture did not affect the reduction of bacteria by the macrophage in the presence of anti-glycolipoprotein serum. The limiting effect of antiserum concentration on macrophage activity was studied, and maximal activity was found at 2%, with no further increase in activity at 5% Preopsonization of the bacteria with anti-glycolipoprotein serum had little effect on the course of phagocytosis within the experimental conditions. Variations in bacterium-to-macrophage input ratios, ranging from 30:1 to 1:30, did not affect the capacity of the macrophages for phagocytosis.
Antibodies against the measles matrix polypeptide after clinical infection and vaccination
Authors: Machamer C E , Hayes E C , Gollobin S D , Westfall L K , Zweerink H J
Published: January 2020

Sera from patients exposed to measles virus were investigated for the presence of antibodies against each of the viral antigens. All sera with measurable neutralizing titers contained antibodies against the two surface proteins (the glycoprotein and fusion protein), the nucleocapsid protein, and one of the internal proteins (P2). However, only sera from individuals with clinical symptoms of measles infection (natural measles and atypical measles) contained antibodies against the measles virus matrix protein. Levels of matrix-specific antibodies were highest in patients with atypical measles infection.
Haemophilus influenzae b infection in rats: effect of splenectomy on bloodstream and meningeal invasion after intravenous and intranasal inoculations
Authors: Moxon E R , Goldthorn J F , Schwartz A D
Published: January 2020

We investigated the effect of splenectomy on the susceptibility of rats to intravenous or intranasal inoculation of Haemophilus influenzae, type b. The 50% lethal dose for asplenic rats inoculated either by intravenous (i.v.) (10(4.7)) or intranasal (i.n.) (10(4.6)) injection was similar, but significantly lower than the 50% lethal dose value in sham-operated rats (10(8.6) i.v. and 10(9.0) i.n.). Mean survival time was significantly longer for asplenic rats inoculated i.n. (49.3 h) compared to asplenic rats inoculated i.v. (24.4h). Similarly, sham-operated rats inoculated i.n. survived significantly longer after i.n. challenge (mean survival time, 171.4 h) than after i.v. challenge (34.7 h). Bacteremia was detected in 100% of asplenic rats and in 80% of sham-operated rats. The geometric mean number of bacteria in the blood of asplenic rats (10(4.90) per ml) was significantly greater than in sham-operated rats (10(3.29) per ml). Meningitis was detected in 7 of 15 randomly sacrificed asplenic rats, whereas none of 15 sham-operated rats had evidence of meningeal invasion. Thus, the asplenic rat was more susceptible to experimentally induced H. influenzae bacteremia, meningitis, and fatal sepsis and offers a biologically relevant experimental model for investigating the role of the spleen in defense against infection with encapsulated bacteria.
Comparison of Virulence Markers of Peritoneal and Fallopian Tube Isolates with Endocervical
Neisseria gonorrhoeae
Isolates from Women with Acute Salpingitis
Authors: Draper D. L. , James J. F. , Brooks G. F. , Sweet R. L.
Published: January 2020

Neisseria gonorrhoeae
strains which cause acute salpingitis are presumed to ascend the genital tract from the cervix. Previous studies utilized isolates obtained from endocervical canal cultures, although it was not known if the isolates truly represented the organisms present in the fallopian tubes. In this study, we compared
N. gonorrhoeae
isolates from endocervical canal cultures with fallopian tube or peritoneal cul-de-sac isolates or isolates from both sites obtained at laparoscopy. Potential virulence markers were studied, including colony phenotype, auxotype, antimicrobial agent susceptibility, protein patterns on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and susceptibility to normal human serum. Six of seven cervical isolates had the same antibiograms and molecular weight for major outer membrane proteins as those of the corresponding peritoneal isolates. Auxotypes also were the same and included prototrophic, proline-requiring, and proline-and-arginine-requiring isolates. The isolates as a group appeared to be very susceptible to the bactericidal action of pooled serum from normal women. Colony phenotypes varied between sites; the fallopian tubecul-de-sac isolates were predominantly of transparent phenotype and piliated. The cervical isolates were either mixtures of equal quantities of opaque and transparent phenotypes or predominantly opaque phenotype. By these markers, patients'
N. gonorrhoeae
cervical isolates appeared to be the same as their isolates from fallopian tubes except for a difference or shift in colony phenotype.
Isolation and characterization of spontaneously arising auxotrophic and Kanagawa phenomenon-negative mutants of Vibrio parahaemolyticus
Authors: Burstyn D G , McNicol L A , Voll M J
Published: January 2020

As a first step toward developing a system of genetic exchange between Vibrio parahaemolyticus strains, spontaneously arising auxotrophic and Kanagawa phenomenon-negative (KP-) mutants were isolated and characterized. Auxotrophic mutants were selected by nalidixic acid enrichment of parental cultures. Some Cys- and Arg- mutants of a KP+ strain were found to be KP-. Reversion to prototrophy by these strains was not accompanied by a return to the parental KP+ phenotype. Additionally, two prototrophic KP- mutants were isolated. No detectable levels of vibriolysin were found in supernatant extracts of KP- mutants by slide gel immunodiffusion analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, or assay for lethal activity in mice. All Cys-, Arg-, and Pur- mutants tested reverted to a different auxotrophy (phenotypic interconversion) as well as to prototrophy. The possible role of insertion sequence-like elements in vibriolysin production and phenotypic interconversion is discussed.
Identification of lactate dehydrogenase-elevating virus as the etiological agent of genetically restricted, age-dependent polioencephalomyelitis of mice
Authors: Martinez D , Brinton M A , Tachovsky T G , Phelps A H
Published: January 2020

The etiological agent of genetically restricted, age-dependent polioencephalomyelitis of mice (the ADPE agent) and several isolates of lactate dehydrogenase-elevating virus (LDV) were compared by biological, physical-chemical and antigenic criteria. The data indicate that the ADPE agent is a strain of LDV. Like LDV, the ADPE agent induced a selective elevation of plasma enzymes and splenomegaly in mice. The enzyme-elevating activity and the paralytogenic activity of the ADPE agent preparations were shown to belong to the same virus. The ADPE agent demonstrated LDV-like replication kinetics in vivo and in vitro. Moreover, the ADPE agent required primary mouse macrophages for in vitro replication, as does LDV. In turn, the LDV isolates induced a paralytic disease with ADPE-like lesions in the spinal cords of immunosuppressed C58 mice. However, the LDV isolates showed a stronger dependence on strain and age of mouse for the induction of paralysis than did the ADPE agent. The LDV isolates and the ADPE agent exhibited indistinguishable morphologies, buoyant densities, structural protein patterns, and virion ribonucleic acid sedimentation rates. Furthermore, they displayed strong antigenic cross-reactivity, as determined by cross-protection in vivo and by radioimmunoassay.
Influence of sublethal concentrations of antibiotics on the expression of the mannose-specific ligand of Escherichia coli
Authors: Eisenstein B I , Beachey E H , Ofek I
Published: January 2020

The ability of streptomycin, in subinhibitory concentrations, to differentially suppress the acquisition of the mannose-binding activity of Escherichia coli was demonstrated in several strains, but not one with a ribosomal mutation to high-level streptomycin resistance, rpsL. We also determined that the growth of bacteria in other antibiotics, notably those that interfere with protein synthesis, resulted in diminished mannose-binding activity (as measured by yeast cell agglutination), degree of piliation (as measured by electron microscopy), and adherence to human oral epithelial cells. The aminoglycoside antibiotics streptomycin, gentamicin, and neomycin had the most marked effects relative to their minimum inhibitory concentrations, followed by tetracycline. Both spectinomycin and chloramphenicol had more effect on adherence than on piliation, although spectinomycin had a more pronounced effect on mannose-binding activity than did chloramphenicol. We conclude that antibiotics, at concentrations below their minimum inhibitory concentration, may have profound effects on surface properties of bacteria that may be pertinent for their ability to colonize and infect human mucosal surfaces. The mechanism(s) may vary from one drug to another, but appear to depend on the classic actions of the antibiotics on inhibiting protein synthesis.
Antitoxic Cholera Immunity in Mice: Influence of Antigen Deposition on Antitoxin-Containing Cells and Protective Immunity in Different Parts of the Intestine
Authors: Lange Stefan , Nygren Håkan , Svennerholm Ann-Mari , Holmgren Jan
Published: January 2020

The importance of the mode of antigen presentation (intravenous, oral, or enteral restricted to the lower ileum) in the development of a local immune response and immunological memory for such a response in different parts of the intestine was studied in mice. Cholera toxin was used as antigen and the immune response was assayed by determining both the number of specific antitoxin-containing cells in the lamina propria and protection against experimental cholera. The results showed that all of these routes of antigen presentation could induce significant memory along the entire small intestine. In contrast, the actual production of antitoxin-containing cells or protective immune response elicited by booster immunization was restricted to those parts of the intestine that were directly exposed to antigen; i.e., lower ileum boosting resulted in immunity in the distal ileum but not in the proximal jejunum, whereas oral or intravenous boosting gave a response in both jejunum and ileum. Protection correlated closely with the number of antitoxin-containing cells in the lamina propria (correlation coefficient, 0.88); ≥4,000 antitoxin-containing cells per mm
3
conferred solid immunity to cholera toxin-induced diarrhea. The total number of immunoglobulin-containing cells in intestines was not significantly influenced by the specific immunizations. There were four times as many of these cells in the upper jejunum (167,000 cells per mm
3
) as in the lower ileum, but the proportions of immunoglobulin A-containing cells (80 to 85%), immunoglobulin M-containing cells (14 to 20%), and immunoglobulin G-containing cells (0.4 to 0.9%) were similar in various parts of the intestine. The results indicate a differential dependence on local tissue antigen for the intestinal antibody-secreting cells and their memory cell precursors.
Relationship among enterotoxigenic phenotypes, serotypes, and sources of strains in enterotoxigenic Escherichia coli
Authors: Reis M H , Matos D P , de Castro A F , Toledo M R , Trabulsi L R
Published: January 2020

The relationship among O groups, O:H serotypes and enterotoxigenic phenotypes was examined in 76 Escherichia coli strains isolated in Brazil from different sources. Of the 17 heat-labile and -stable enterotoxin (LT/ST)-producing strains whose O antigens were identified, 15 belonged to serotypes O6:H16 (7 strains), O63:H- (5 strains), and O139:H28 (3 strains). All 11 ST strains were in group OO128PAC, which was represented by four O:H serotypes. The 23 LT strains with the O antigen identified were distributed among serotypes of 14 O groups. Colonization factor CFA/I was not found in any of the LT strains, but it was found in six LT/ST and three ST strains. On the whole, each E. coli O:H serotype had a particular fermentation pattern. LT/ST as well as ST strains were all isolated from patients with diarrhea, whereas LT strains were isolated from patients with diarrhea, normal children, food, and river water.
Isolation of a Soluble Component of
Plasmodium berghei
Which Induces Immunity in Rats
Authors: Grothaus G. D. , Kreier J. P.
Published: January 2020

Soluble material was obtained from sonically freed plasmodiae by three procedures. Two procedures, cryo-impacting and freeze-thawing, were evaluated for their ability to disrupt the parasites and release soluble material. The soluble materials obtained by these procedures were compared to materials washed from the surfaces of sonically freed parasites. Between 35 and 40% of the total parasite protein was solubilized by freeze-thawing or cryo-impacting. One cycle of freeze-thawing released nearly as much protein as could be released by this method, and additional cycles of freeze-thawing had little additional effect. Cryo-impacting solubilized only a small amount of protein in addition to that which was released by the cycle of freeze-thawing inherent in the procedure. Reductions in the packed cell volume of the material remaining after freeze-thawing or cryo-impacting indicate that the insoluble fragments are broken into smaller pieces as treatment is extended. Electron microscopy of 30-s cryo-impacted and three-times freeze-thawed parasites revealed membrane fragments similar in appearance. Patterns obtained by polyacrylamide gel electrophoresis of the soluble material from freeze-thawed and cryo-impacted parasites were also similar, and approximately 13 protein bands were demonstrated. The material washed from the surfaces of the free parasites, on the other hand, resolved into only two to four major bands on the gel columns. In immunization studies, the soluble and insoluble fractions obtained by freeze-thawing or cryo-impacting and the material washed from the surfaces of the parasites all stimulated a protective immune response. On the basis of the amount of protein required to stimulate roughly comparable immunity, the soluble fraction obtained by freeze-thawing or cryo-impacting free parasites was about twice as potent an immunogen as was the insoluble fraction. The material obtained by gentle washing of the freed parasites was approximately 20 times as potent an immunogen as were the freed parasites and about 7 times as potent as the soluble material obtained by freeze-thawing or cryo-impacting.
Immunoglobulin E in patients with Japanese encephalitis
Authors: Pavri K M , Ramamoorthy C L , Dhorje S
Published: January 2020

Significantly high levels of immunoglobulin E in the acute sera of encephalitis cases (suspected or confirmed as Japanese encephalitis) declined sharply during early convalescence.
Pathogenic properties of Yersinia enterocolitica
Authors: Mors V , Pai C H
Published: January 2020

A total of 88 isolates of Yersinia enterocolitica was examined for heat-stable enterotoxin production and ability to penetrate HeLa cells and evoke keratoconjunctivitis in guinea pigs (Séreny test) as potential pathogenic properties. All 49 isolates belonging to serotypes O:3, O:8, O:9, and O:5,27 and only 5 of 39 strains of other serotypes were HeLa positive. Séreny-positive strains were found only in serotype O:8. Heat-stable enterotoxin production was almost ubiquitous in all serotypes. Y. enterocolitica strains were classified into five groups with regard to their potential pathogenic properties.