bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors influencing adherence of group B streptococci to human vaginal epithelial cells
Authors: Zawaneh S M , Ayoub E M , Baer H , Cruz A C , Spellacy W N
Published: January 2020

Factors affecting the adherence of group B streptococci to human vaginal epithelial cells in vitro were examined. Maximal adherence was achieved within 15 min of incubation of bacteria with epithelial cells. Adherence was temperature and pH dependent; maximal adherence occurred at 37 degrees C and pH 5.5. Killing of streptococci with ultraviolet light or penicillin did not affect adherence. Similarly, adherence was not altered by preincubating epithelial cells at 65 degrees C for 30 min. Thus neither bacterial nor epithelial cell viability appears to be a prerequisite for adherence. Preincubation of streptococci at 65 degrees C for 30 min resulted in a marked decrease in adherence, whereas preincubation of group B streptococci with neuraminidase was associated with a significant increase in adherence. The adherence of strains belonging to five different group B streptococcal serotypes was not altered by group-specific or type-specific rabbit antisera. These findings suggest that the site for adherence on the bacterial cell wall is heat sensitive and is marked by sialic acid, but is not related to either group-specific or type-specific antigens.
Neuraminidase-dependent hamagglutination of human erythrocytes by human strains of Actinomyces viscosus and Actinomyces naeslundii
Authors: Costello A H , Cisar J O , Kolenbrander P E , Gabriel O
Published: January 2020

Human A, B, and O erythrocytes (RBC) were agglutinated by many human strains of Actinomyces viscosus and A. naeslundii. At 37 degrees C, these bacterium-mediated hemagglutination reactions required the action of bacterial neuraminidase upon the RBC; however, at 4 degrees C, the requirement for neuraminidase was not as striking. Bacterial cell suspensions which caused hemagglutination at 37 degrees C contained both soluble extracellular and cell-associated neuraminidase activities as shown by enzyme assays using a soluble substrate (i.e., alpha 1-acid glycoprotein). Bacterium-mediated hemagglutination occurred only in the presence of soluble neuraminidase activity, and the rate of hemagglutination could be inhibited by 2-deoxy-2,3-dehydro-N-acetylneuraminic acid, a competitive inhibitor of purified soluble neuraminidase from A. viscosus T14V. Suspensions of bacteria which contained only cell-associated neuraminidase activity were unable to initiate hemagglutination, but they caused immediate hemagglutination when mixed with neuraminidase-treated RBC. All hemagglutination reactions were reversible in the presence of 0.02 M lactose and were abolished by heating (85 degrees C for 30 min) the actinomycete cells but not the RBC. The proposed mechanism of hemagglutination involves two sequential steps: (i) the action of neuraminidase to unmask galactose-containing receptors on the RBC and (ii) the multivalent binding of these receptors by many low-affinity lection sites on the bacterial surface.
Humoral immunity in the resolution of genital infection in female guinea pigs infected with the agent of guinea pig inclusion conjunctivitis
Authors: Rank R G , White H J , Barron A L
Published: January 2020

Female guinea pigs infected in the genital tract with the chlamydial agent of guinea pig inclusion conjunctivitis were selectively immunosuppressed by varying regimens of cyclophosphamide (Cy) treatment. Temporary suppression of both humoral and cell-mediated immunity by daily treatment of Cy (25 mg/kg) for 13 days resulted in a prolonged infection, whereas daily treatment for the duration of the experiment totally prevented the development of humoral and cell-mediated responses and produced an intense and prolonged infection which did not resolve. When humoral immunity alone was suppressed by treatment with Cy (250 and 150 mg/kg) at 9-day intervals, the infection again did not resolve. Treatment with 100 mg of Cy per kg at 9-day intervals resulted in an extended infection which resolved concomitantly with the development of antibody to guinea pig inclusion conjunctivitis. These data indicate that humoral immunity is essential for the recovery of female guinea pigs from guinea pig inclusion conjunctivitis genital infection. A market weight loss was observed which could not be attributed to Cy treatment alone. Edematous and ulcerative changes of the external genitalia were also noted.
Failure to detect naturally occurring serum inhibitors of hepatitis B virus deoxyribonucleic acid polymerase
Authors: Hess G , Arnold G , Dormeyer H H , Koesters W , Gahl G , Hoffmann H G , Schönborn H , Meyer zum Büschenfelde K H
Published: January 2020

Sera of patients with past or ongoing hepatitis -B virus infection were tested for the presence of inhibitors of hepatitis -B virus-specific deoxyribonucleic acid (DNA) polymerase activity. None of the sera tested, which included those from anti-hepatitis B surface- and anti-hepatitis B core antigen-positive hemophiliacs, anti-hepatitis Bc antigen-positive hepatitis B surface antigen carriers, patients with hepatitis B surface antigen-positive chronic active hepatitis, hepatitis B surface antigen-positive hemodialysis patients, tumor patients with minimal hepatitis, patients with acute type B, type A, and type non-A, non-B hepatitis and individuals with autoimmune phenomena, contained inhibitors of DNA polymerase activity. This implies that the DNA polymerase test is not affected when utilized to quantitate DNA-containing Dane particles. In addition, there is no evidence that inhibitors of DNA polymerase activity play some pathogenic role in the course of hepatitis B virus infection.
Macrophage stimulation in vitro by an inactive muramyl dipeptide derivative after conjugation to a multi-poly(DL-alanyl)-poly(L-lysine) carrier
Authors: Galelli A , Le Garrec Y , Chedid L , Lefrancier P , Derrien M , Level M
Published: January 2020

It has been previously reported that N-acetyl-muramyl-L-alanyl-D-isoglutamine (MDP), which represents the minimal structure that can substitute for mycobacteria in Freund complete adjuvant, activated macrophages in vitro and in vivo. In the present study we show that, in contrast to MDP, the nonadjuvant MDP(DD) stereoisomer has no effect on cytostatic activity of thioglycolate-induced macrophages as measured by uptake of [3H]thymidine. However, surprisingly, after conjugation to an inert carrier, multi-poly(DL-alanyl)-poly(L-lysine), this compound activates macrophages in vitro and becomes at least as effective as MDP. It has also been shown in other studies that after conjugation MDP(DD) remained devoid of antigenicity and of adjuvant activity although such a conjugate could increase resistance to infection. It, therefore, appears that there exists no correlation between the structure required for adjuvant activity and the structure required for macrophage activation or for enhancement of nonspecific immunity.
Generation and characterization of a lipopolysaccharide-induced and serum-derived cytotoxic factor for tumor cells
Authors: Männel D N , Meltzer M S , Mergenhagen S E
Published: January 2020

Serum from Mycobacterium bovis BCG-infected mice treated with lipopolysaccharide was cytotoxic to tumor cells in vitro. Serum-induced cytotoxicity was estimated by measuring release of [3H]thymidine into culture supernatants of prelabeled tumor target cells. Serum from BCG-infected mice not treated with lipopolysaccharide or from uninfected mice treated with lipopolysaccharide was inactive. Moreover, although serum cytotoxic activity was evident with 10 syngeneic or allogeneic tumor cell lines, little or no effect was observed with normal embryonic fibroblast target cells. Maximal titers of serum cytotoxic activity were detected 14 days after BCG infection and 2 h after LPS treatment. Serum of BCT-infected, T-cell-deficient nude mice developed strong cytotoxic activity after LPS treatment; however, lipopolysaccharide-insensitive C3H/HeJ mice could produce this cytotoxic activity only after adoptive transfer with lipopolysaccharide-responsive C3H/HeN bone marrow. Physicochemical characterization of the serum cytotoxic activity revealed a heat-stable (56 degrees C, 30 min) entity with a molecular weight of about 60,000 and an isoelectric point at pH 4.8. Biological and physicochemical characteristics of this serum cytotoxic activity as defined by an in vitro assay were very similar to characteristics of tumor necrosis factor and suggest that this molecule may be a major effector mechanism for the antitumor actions of lipopolysaccharide.
Immunobead enzyme-linked immunosorbent assay for quantitating immunoglobulin A in human secretions and serum
Authors: Sack D A , Neogi P K , Alam M K
Published: January 2020

We have developed an enzyme-linked immunosorbent assay for quantitating human immunoglobulin A in human secretions and serum. The procedure uses Immunobeads as the solid phase, has a sensitivity of 10 ng/ml, and can be completed in 1 day. Since there is no diffusion through agar, the assay does not require a correction factor when measuring secretory immunoglobulin A. This method should be useful in studies of local mucosal immunity in humans, especially when a very sensitive assay is needed.
Distribution of Cryptococcus neoformans in a natural site
Authors: Ruiz A , Fromtling R A , Bulmer G S
Published: January 2020

Pigeon droppings in a vacant tower were assayed for the number and size of viable cells of Cryptococcus neoformans. The dry, thinly scattered floor debris contained 2.6 x 10(6) viable cells per g--300 times more cells than were cultured from a large, compact pile of pigeon droppings (7.4 x 10(3) cells per g). Aerosols generated from floor debris containing pigeon droppings had an average of 360 viable cells in 31 liters of air; 27 of these cells (7.5%) were 1.1 to 3.3 micrometers in diameter and, therefore, capable of human lung deposition. Environmental factors which may influence the distribution, survival, and proliferation of C. neoformans in nature are discussed.
Complement requirement for virus neutralization by antibody and reduced serum complement levels associated with experimental equine herpesvirus 1 infection
Authors: Snyder D B , Myrup A C , Dutta S K
Published: January 2020

Pony foals, negative for detectable serum-neutralizing antibody to equine herpesvirus 1 by the standard tube-culture virus neutralization test, were experimentally infected with equine herpesvirus 1. Complement-requiring (CR) and non-complement-requiring (NCR) serum-neutralizing antibodies were evaluated in preinfection and postinfection sera by means of a complement-enhanced plaque reduction assay. Low levels of CR antibodies were found in the preinfection sera of only group II ponies. Upon infection, CR antibodies were detected by day 2 postinfection and reached peak titers between 7 and 14 days postinfection in the antisera of all ponies. NCR antibodies were detected later than CR antibodies and at levels approximately 40 to 150 times lower than the latter. CR/NCR ratios indicated that complement requirement was greatest early in the acute stages of disease and that this requirement decreased during the convalescent phase. Fractionation of 1-week and 2-week postinfection antisera of group I ponies indicated the CR antibody activity resided in both the 7S and 19S fractions. Total serum complement levels of the ponies were quantified throughout the infection with an equine anti-goat erythrocyte hemolytic system. In vivo, complement levels were depressed for all ponies during the first 2 weeks of infection. A decline in complement levels was seen as early as day 2, and they decreased to an average of 35% of preinfection levels on day 10 postinfection for all ponies.
Dengue-2 vaccine: virological, immunological, and clinical responses of six yellow fever-immune recipients
Authors: Bancroft W H , Top F H , Eckels K H , Anderson J H , McCown J M , Russell P K
Published: January 2020

Six male volunteers, previously immunized with yellow fever vaccine, were inoculated subcutaneously with a live, attenuated dengue-2 virus (PR-159/S-1) candidate vaccine. Five recipients developed viremia 8 or 9 days after vaccination, which lasted 1 to 10 days. The onset of viremia was followed by fever in three people, transient leukopenia in four, and an erythematous rash in one. One volunteer developed an oral temperature of 38.8 degrees C with headache, myalgia, fatigue, and photophobia suggestive of mild dengue fever. All five viremic volunteers developed fourfold or greater rises in serum neutralizing antibody. The sixth volunteer, who had a low titer of preexisting dengue-2 neutralizing antibody, had no viremia, no symptoms, and a modest rise in hemagglutination inhibiting antibody. Virus isolates obtained from plasma retained the small-plaque and temperature-sensitive growth characteristics of the vaccine virus in vitro. In this study, the vaccine virus genetically stable and immunogenic and seemed sufficiently attenuated for additional testing in humans.
Characterization of plasmids and plasmid-associated determinants of Yersinia enterocolitica pathogenesis
Authors: Portnoy D A , Moseley S L , Falkow S
Published: January 2020

Yersinia enterocolitica isolates harboring a particular species of plasmid deoxyribonucleic acid showed a high degree of lethality for gerbils and caused the detachment of HEp-2 tissue cell monolayers. Strains cured of their plasmid deoxyribonucleic acid showed loss of these properties. However, invasiveness of HEp-2 cells was shown not to be a plasmid-mediated property. The expression of plasmid-associated properties, including at least three major outer membrane polypeptides, occurred during growth at 37 but not at 25 degrees C and was related to the concentration of calcium in the growth medium. The plasmid species associated with these properties ranged in molecular mass from 40 x 10(6) to 48 x 10(6) daltons and comprised a family of related plasmids.
Purification and partial characterization of the major outer membrane protein of Chlamydia trachomatis
Authors: Caldwell H D , Kromhout J , Schachter J
Published: January 2020

Elementary bodies (EB) of Chlamydia trachomatis serotypes C, E, and L2 were extrinsically radioiodinated, and whole-cell lysates of these serotypes were compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Autoradiography of the polypeptide profiles identified a major surface protein with an apparent subunit molecular weight of 39,500 that was common to each C. trachomatis serotype. The abilities of nonionic (Triton X-100), dipolar ionic (Zwittergent TM-314), mild (sodium deoxycholate and sodium N-lauroyl sarcosine), and strongly anionic (SDS) detergents to extract this protein from intact EB of the L2 serotype were investigated by SDS-PAGE analysis of the soluble and insoluble fractions obtained after each detergent treatment. Only SDS readily extracted this protein from intact EB. Sarkosyl treatment selectively solubilized the majority of other EB proteins, leaving the 39,500-dalton protein associated with the Sarkosyl-insoluble fraction. Ultrastructural studies of the Sarkosyl-insoluble EB pellet showed it to consist of empty EB particles possessing an apparently intact outer membrane. No structural evidence for a peptidoglycan-like cell wall was found. Morphologically these chlamydial outer membrane complexes (COMC) resembled intact chlamydial EB outer membranes. The 39,500-dalton outer membrane protein was quantitatively extracted from COMC by treating them with 2% SDS at 60 degrees C. This protein accounted for 61% of the total COMC-associated protein, and its extraction resulted in a concomitant loss of the COMC membrane structure and morphology. The soluble extract obtained from SDS-treated COMC was adsorbed to a hydroxylapatite column and eluted with a linear sodium phosphate gradient. The 39,500-dalton protein was eluted from the column as a single peak at a phosphate concentration of approximately 0.3 M. The eluted protein was nearly homogeneous by SDS-PAGE and appeared free of contaminating carbohydrate, glycolipid, and nucleic acid. Hyperimmune mouse antiserum prepared against the 39,500-dalton protein from serotype L2 reacted with C. trachomatis serotypes Ba, E, D, K, L1, L2, and L3 by indirect immunofluorescence with EB but failed to react with serotypes A, B, C, F, G, H, I, and J, with the C. trachomatis mouse pneumonitis strain, or with the C. psittaci feline pneumonitis, guinea pig inclusion conjunctivitis, or 6BC strains. Thus, the 39,500-dalton major outer membrane protein is a serogroup antigen of C. trachomatis organisms.
Macrophages in resistance to rickettsial infections: early host defense mechanisms in experimental scrub typhus
Authors: Nacy C A , Groves M G
Published: January 2020

Several early nonspecific host defense mechanisms were examined in resistant (BALB/c) and susceptible (C3H/He) mice after intraperitoneal inoculation with Rickettsia tsutsugamushi strain Gilliam. Inflammatory exudates were formed in both mouse strains in response to rickettsial inoculation, but the inflammatory response of C3H animals was delayed several days, and influx of peroxidase-positive macrophages occurred late in infection. Peritoneal cells of C3H mice became progressively infected, with 40% of both macrophages and lymphocytes containing intracellular rickettsiae by day 10. The early flammatory response of BALB/c mice was unexpectedly associated with a low percentage of infected peritoneal cells (1 to 2%). In vitro, no difference was detected in ability of resident macrophages of either strain to support the growth of R. tsutsugamushi or to become activated by treatment with lymphokines for rickettsiacidal activity. In vivo, however, macrophages from C3H mice inoculated with Gilliam were not activated on days 6 and 7 after infection, whereas BALB/c macrophages were continuously activated beginning on day 4. The lack of in vivo C3H macrophage activation was not secondary to deficient lymphokine production by infected lymphocytes, as levels of lymphokines produced by peritoneal lymphocytes of both strains were similar and peaked on day 7 after infection. Susceptibility to infection appears to be related to defective regulation of macrophage responses rather than to defects in macrophage function.
Syncytium-forming virus of common marmosets (Callithrix jacchus jacchus)
Authors: Marczynska B , Jones C J , Wolfe L G
Published: January 2020

This communication describes the isolation and characterization of a new syncytium-forming virus of common marmosets (Callithrix jacchus jacchus). The virus, isolated from skin explants and peripheral leukocytes of healthy animals, induced syncytia and subsequent cytolysis of several human, simian, and rodent fibroblastic cultures and induced a carrier state in mixed fibroblastic-epithelial or epithelial cell lines. Cytoplasmic and nuclear viral antigen was demonstrated in infected cells by indirect immunofluorescence tests using serum obtained from persistently infected common marmosets. Abundant virus particles were detected within cisternae of endoplasmic reticulum of lytically infected cells by electron microscopy. The virus incorporated [3H]uridine, banded at a density of 1.14 to 1.16 g/cm3 in sucrose, and possessed ribonucleic acid-dependent deoxyribonucleic acid polymerase. No antigenic cross-reactivity was detected between the marmoset virus and simian foamy virus serotypes 1 to 8 in neutralization and immunofluorescence assays. A seroepidemiological survey of a marmoset colony revealed that 53.5% of common marmosets contained antibodies against the virus, whereas other species of marmosets maintained in the same colony remained free of antibodies.
Immunotherapy of experimental cancer with a mixture of synthetic muramyl dipeptide and trehalose dimycolate
Authors: Yarkoni E , Lederer E , Rapp H J
Published: January 2020

The antitumor activity of a mixture of synthetic N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) and trehalose-6,6'-dimycolate (TDM) (MDP+TDM) in emulsified form was studied in guinea pigs, each with a syngeneic dermal tumor and microscopically detectable metastases in regional lymph nodes. A single intralesional administration of an ultrasonically prepared emulsion containing MDP+TDM in squalane or in mineral oil caused tumor regression and elimination of lymph node metastases. Similar emulsions of MDP+TDM made with squalene or hexadecane were immunotherapeutically inactive.
High interferon titer in newborn pig intestine during experimentally induced viral enteritis
Authors: La Bonnardiere C , Laude H
Published: January 2020

We looked for the presence of interferon in the digestive tract of newborn piglets infected with a virulent strain of transmissible gastroenteritis virus (Coronaviridae). High levels of type 1 interferon activity were found early in the disease in jejunal and ileal parts of the intestine as well as in the serum. Enterocytes appeared to be involved in the interferon synthesis. These findings raise the question of the role of interferon in the pathogenesis of viral enteritis.
Interferon production by human mononuclear leukocytes: differences between respiratory syncytial virus and influenza viruses
Authors: Chonmaitree T , Roberts N J , Douglas R G , Hall C B , Simons R L
Published: January 2020

The ability of respiratory syncytial virus (RSV) to induce interferon production by human mononuclear leukocytes was compared with that of influenza viruses. Cell culture fluids were assayed for interferon activity 1, 3 and 7 days after exposure to RSV or to one of two subtypes of influenza A virus (H0N1 and H3N2). RSV induced interferon production inconsistently and in low titers. Varying the multiplicity of infection did not improve the ability of RSV to induce interferon production. In contrast, influenza viruses were effective inducers of interferon production. Seropositivity to the influenza virus strains was not associated with increased interferon titers. Interferon produced after exposure to RSV or to the influenza viruses was resistant to low pH treatment. The data suggest that interferon production may not be a major component of human immunological defense against RSV infection.
Antibody to group B Streptococcus type III in human sera measured by a mouse protection test
Authors: Baltimore R S , Baker C J , Kasper D L
Published: January 2020

Antibody to group B Streptococcus type III (GBS-III) was measured in human plasma and sera by using a test which measures the ability to protect outbred albino mice from an intraperitoneal challenge of GBS-III calculated to be lethal to 90% of the mice (LD90 dose). Of three samples from three different lots of commercial human immune serum globulin, none were protective despite the presence of antibody to the native type III polysaccharide. Nine specimens were tested from recipients of multivalent pneumococcal vaccine, and none were protective. Five specimens were tested from recipients of GBS-III polysaccharide vaccines who had responded with greater than 50 micrograms of specific antibody per ml in the blood. All of these were protective and could be diluted to titers of 1:10 to 1:40. Of two prevaccination sera with low levels of specific antibody, neither was protective. An unexpected finding which may limit the sensitivity of the mouse protection assay was that the human immune serum globulin and human serum with a very low level of antibody appeared to increase the lethality of the GBS-III test strain, resulting in LD50 values reduced to 0.01 of the usual LD50.
Sex-related differences in the pattern of coxsackievirus B-3-induced immune spleen cell cytotoxicity against virus-infected myofibers
Authors: Huber S A , Job L P , Woodruff J F
Published: January 2020

Spleen cells from adult BALB/c mice injected intraperitoneally with purified coxsackievirus B-3 were tested for cytotoxicity against 51Cr-labeled syngeneic infected and uninfected myofibers. Both male and female immune cells were active against uninfected targets; this reactivity was evident by day 3 of infection and persisted throughout the first week. However, we observed marked sex-related differences in immune cell cytotoxicities against infected myofibers. Males exhibited a strong T-lymphocyte response 4 to 7 days after infection. In contrast, females exhibited a weak response, and only infrequently were the immune spleen cells of females significantly more reactive against infected myofibers than against uninfected myofibers. The demonstration of a stronger effector cell response against infected myocardial cells in male mice correlates with the observation that clinical adult coxsackievirus B myocarditis and pericarditis occur predominantly in males.
Ability of an avirulent mutant of Vibrio cholerae to colonize in the infant mouse upper bowel
Authors: Sigel S P , Finkelstein R A , Parker C D
Published: January 2020

Vibrio cholerae strain 3083 (biotype El Tor, serotype Ogawa) and Texas Star-SR (SR), a mutant derived from 3083 that produces the B (binding) but not the A (toxic) subunit of choleragen, were compared in their abilities to: (i) associate with the infant mouse upper bowel; (ii) survive and multiple there; and (iii) induce diarrhea. Vibrios labeled with 35SO4 were used to determine association with the upper bowel and ability to multiply. The parental strain associated significantly better than SR, although viable mutant cells were found in the infant mouse intestine 16 to 18 h after challenge. Addition of exogenous toxin enhanced the rate at which labeled SR (but not 3083) was cleared, further suggesting that SR associates less well with the upper bowel. Both SR and 3083 multiplied in the upper bowel but, due perhaps to slight net killing during the first 3 h and its more rapid rate of clearance, SR achieved a population size only 10% that of 3083 by 8 h postchallenge. Strain 3083 elicited diarrhea in infant mice but SR did not, even after 10 successive passages through the infant mouse intestine. Strain SR was slightly temperature sensitive at 37 and 40 degrees C. Its potential use as a live vaccine is discussed.
Escherichia coli adhesion to Saccharomyces cerevisiae and mammalian cells: role of piliation and surface hydrophobicity
Authors: Jann K , Schmidt G , Blumenstock E , Vosbeck K
Published: January 2020

A number of Escherichia coli strains isolated from patients with urinary tract infections, bacteremia, or diarrhea were studied with respect to their (i) capacity to agglutinate human AB, bovine, and guinea pig erythrocytes as well as yeast (Saccharomyces cerevisiae) cells; (ii) adhesion to monolayers of cells from human intestine (intestine 407; ATCC CCL6), monkey kidney (Vero; ATCC CCL81), feline embryo (Flow no. 05-552), and porcine kidney (PK1; ATCC CRL1392) and of primary rat kidney cell cultures; and (iii) surface hydrophobicity as measured by hydrophobic interaction chromatography. No correlation could be found between the capacity of the bacteria to adhere to the different cultured mammalian cells and their agglutination patterns. The results indicated not only a complexity of bacterial receptors on the eucaryotic cells, but also a multiplicity of bacterial adhesions as expressed by the selectivity of bacterial binding. Binding of bacteria was found to be attributed to the presence of pili on the bacterial surface. It was observed that the bacteria were differently piliated: some had only common type I or related pili which gave rise to mannose-sensitive (MS) adhesion or agglutination (MS pili), some had only pili which gave rise to mannose-resistant (MR) adhesion or agglutination (MR pili), and some had both MS and MR pili. Bacteria with MS pili were more hydrophobic than those with MR pili or with none at all.
Monoclonal antibodies to herpes simplex virus type 1 proteins, including the immediate-early protein ICP 4
Authors: Showalter S D , Zweig M , Hampar B
Published: January 2020

Monoclonal antibodies were prepared against herpes simplex virus type 1 (strain 14012) by two immunization procedures. Procedure A utilized infectious virus propagated in mouse cells, and procedure B utilized mouse cells infected with herpes simplex virus in the presence of cycloheximide and harvested 1 h after removal of the inhibitor. A total of 52 monoclonal antibodies were obtained against 10 herpes simplex virus proteins, including four glycosylated proteins (a 110,000-molecular-weight protein, gB, gC, and gD) and six nonglycosylated proteins (a 68,000-molecular-weight protein, ICP 9, ICP 8, ICP 6, ICP 5, and the immediate-early ICP 4). The antibodies were assayed against herpes simplex virus types 1 and 2 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of radioimmunoprecipitates, immunofluorescence, and neutralization. Using the reagents prepared, we concluded that the 110,000-molecular-weight protein, gD, ICP 9, ICP 9, ICP 6, and the 68,000-molecular-weight protein express both type-specific and cross-reactive antigenic determinants. In contrast, nine antibodies against gB all cross-reacted with herpes simplex virus type 2, whereas eight antibodies to gC all reacted type specifically.
Safety and immunogenicity of group Y and group W135 meningococcal capsular polysaccharide vaccines in adults
Authors: Griffiss J M , Brandt B L , Altieri P L , Pier G B , Berman S L
Published: January 2020

Serogroup Y and W135 Neisseria meningitidis capsular polysaccharide vaccines were tested as monovalent and divalent preparations in groups of 10 adult human volunteers at a dose of 50 (monovalent) or 100 micrograms (divalent) injected subcutaneously. Reactogenicity was low for the group Y vaccine and the group Y-W135 combined vaccine; 3 of 10 volunteers developed systemic reactions after group W135 vaccination. All three vaccines induced significant homologous and heterologous binding and bactericidal antibody. Except for group W135 bactericidal antibody, homologous responses exceeded heterologous responses, and divalent and monovalent vaccines induced equivalent homologous responses. Homologous bactericidal antibody responses were maintained for 4 weeks in 85% of group W135 vaccinates and in 100% of group Y vaccinates. Bactericidal antibody was induced in 11 of 11 group Y and 12 of 15 group W135 volunteers without preexisting respective bactericidal activities, regardless of which vaccine they received. For all three vaccines, antibody levels declined only slightly over 6 months. Prevaccination antibody levels positively affected postvaccination binding antibody levels, but not bactericidal levels.
Factors affecting phaeomelanin production by a melanin-producing (mel) mutant of Vibrio cholerae
Authors: Ivins B E , Holmes R K
Published: January 2020

In a previous study we isolated melanin-producing (mel) mutants of Vibrio cholerae and demonstrated that production of melanin during growth on solid media was stimulated by L-tyrosine and L-cysteine. In the studies reported here we analyzed factors that affected melanin production in liquid media and determined the abilities of radioactively labeled amino acids to serve as precursors for the formation of melanin by V. cholerae. Radioactivity from L-cysteine and from L-tyrosine was preferentially incorporated into partially purified melanin, providing further evidence for production of phaeomelanin by V. cholerae. Cuprous ions stimulated production of melanin by V. cholerae in defined liquid medium, but melanin formation was inhibited by high concentrations of L-cysteine or thiouracil. The inhibition of melanin formation by sulfhydryl compounds is most likely due to their ability to bind copper ions that are essential for tyrosinase activity.
Evidence for a bladder cell glycolipid receptor for Escherichia coli and the effect of neuraminic acid and colominic acid on adherence
Authors: Davis C P , Avots-Avotins A E , Fader R C
Published: January 2020

The rat bladder epithelial cell receptors involved in mannose-sensitive adherence of Escherichia coli strains were studied. Sodium metaperiodate and lipase pretreatment of epithelial cells significantly reduced bacterial adherence to cells whereas trypsin and phospholipase C had a marginal or insignificant effect on adherence. Neuraminidase and colominic acid significantly increased adherence, whereas N-acetylneuraminic acid significantly reduced adherence. These data suggest that the rat bladder epithelial cell receptors involved in mannose-sensitive adherence are glycolipids. In addition, the data suggested that sialic acid on bladder epithelial cells acts as a nonspecific inhibitor of adherence, whereas colominic acid, a component of some E. coli K1 capsules, may act as a promoter of adherence.
Evidence for autoantibody production associated with polyclonal B-cell activation by Pseudomonas aeruginosa
Authors: Garzelli C , Campa M , Colizzi V , Benedettini G , Falcone G
Published: January 2020

Experimental infection of mice with Pseudomonas aeruginosa resulted in the polyclonal activation of B lymphocytes, as assessed by the spontaneous plaque-forming cell (PFC) response to trinitrophenyl and sheep erythrocytes. Additionally, a PFC response to bromelain-treated syngeneic erythrocytes (Br-MRBC) could be detected in infected mice, suggesting that P. aeruginosa infection might also induce activation of self-reactive B-cell clones and consequently lead to autoantibody production. Furthermore, in cultures of mouse peritoneal cells, heat-killed P. aeruginosa enhanced the development of anti-Br-MRBC PFC, even under conditions where cell division was blocked, suggesting that the in vitro P. aeruginosa-induced enhancement of anti-Br-MRBC PFC was essentially related to cell differentiation, cell division playing only a minor role. The mechanism of the in vivo and in vitro P. aeruginosa-induced activation of anti-Br-MRBC PFC are discussed.
Transfer of resistance with syphilitic immune cells: lack of correlation with mitogenic activity
Authors: Schell R F , LeFrock J L , Chan J K
Published: January 2020

Hamsters infected intradermally with Treponema pallidum Bosnia A develop extensive chronic skin lesions, usually accompanied by metastatic lesions involving the paws, lips, and anal region and by lymph nodes teeming with treponemes. Throughout the course of syphilitic infection, cells from the inguinal lymph nodes responded poorly to stimulation with suboptimal, optimal, or supraoptimal concentrations of concanavalin A, phytohemagglutinin P, or lipopolysaccharide. The response of syphilitic spleen cells was variable. Depression of lymphocyte reactivity to mitogens preceded clinical signs of infection and correlated well with the chronicity of syphilitic infection. When syphilitic hamsters were treated with a curative dose of penicillin, their mitogenic responses returned to normal or were slightly elevated. No correlation existed between mitogenic activity and the ability of lymphoid cells to induce an effective immune response when transferred to normal recipients. No significant differences in protection were detected among recipients of immune cells with or without activity to mitogens. These results demonstrate that lymphocyte transformation by mitogens in vitro is not a measure of effective treponemicidal activity and so may not be a valid indicator of the protective immune status of syphilitic animals.
Depression of monocyte and polymorphonuclear leukocyte oxidative metabolism and bactericidal capacity by influenza A virus
Authors: Abramson J S , Mills E L , Giebink G S , Quie P G
Published: January 2020

Decreased host defense against bacterial disease associated with influenza infection may be related to virus-induced changes in phagocytic cell function. Influenza A virus initiates the respiratory burst in peripheral blood monocytes and polymorphonuclear leukocytes, with a peak chemiluminescent response approximately 3 min after virus is added to the cells in vitro. Electron micrographs of phagocytic cells incubated with influenza virus demonstrated virus attached to the cell membrane and within phagocytic vacuoles. After 20 min of incubation of the virus with phagocytic cells, the chemiluminescent response to opsonized zymosan or phorbol myristate acetate was decreased by 30 to 90%. Phagocytic activity of monocytes and polymorphonuclear leukocytes incubate with influenza virus was normal, but the bactericidal activity was significantly depressed. Influenza A virus therefore stimulates an oxidative burst in monocytes as well as polymorphonuclear leukocytes, leading to a subsequent depression of the oxidative metabolic response and bactericidal capacity of the phagocytic cells.
Serological analysis of herpes simplex virus types 1 and 2 with monoclonal antibodies
Authors: Pereira L , Dondero D V , Gallo D , Devlin V , Woodie J D
Published: January 2020

A panel of monoclonal antibodies to herpes simplex virus glycoproteins was used for serological analysis of 130 strains. Based on specific immunological determinants, strains of each serotype clustered into subgroups. Monoclonal antibodies were suitable reagents for serotyping and have potential application to epidemiology of herpes simplex virus infections.
Cytotoxin of Pasteurella haemolytica acting on bovine leukocytes
Authors: Shewen P E , Wilkie B N
Published: January 2020

The toxicity of Pasteurella haemolytica culture supernatant for bovine and porcine cells was evaluated by 51Cr release. Sterile bacterial culture supernatant was toxic for bovine pulmonary lavage cells, peripheral blood lymphocytes and neutrophils, and cultured peripheral blood mononuclear cells, resulting in marked 51Cr release. Only slight release was induced from cultured Madin-Darby bovine kidney cells, porcine pulmonary lavage cells, peripheral blood mononuclear cells, lymphocytes, or neutrophils. No release was detected with primary bovine spleen cell cultures, bovine erythrocytes, or porcine erythrocytes. The demonstrated specificity of this cytotoxin for bovine leukocytic cells may be important in the pathogenesis of bovine pneumonic pasteurellosis.
Berberine inhibits intestinal secretory response of Vibrio cholerae and Escherichia coli enterotoxins
Authors: Sack R B , Froehlich J L
Published: January 2020

Berberine, an alkaloid from the plant Berberis aristata, which has been known since ancient times as an antidiarrheal medication in India and China, inhibited by approximately 70% the secretory responses of the heat-labile enterotoxins of Vibrio cholerae and Escherichia coli in the rabbit ligated intestinal loop model. The drug was effective when given either before or after enterotoxin binding and when given either intraluminally or parenterally; it did not inhibit the stimulation of adenylate cyclase by cholera enterotoxin and caused no histological damage to intestinal mucosa. Berberine also markedly inhibited the secretory response of E. coli heat-stable enterotoxin in the infant mouse model. Although the mechanism of action of the drug is not yet known, these data provide a rationale for its apparent clinical usefulness in treating acute diarrheal disease.
Failure to detect killer cell activity in rabbits
Authors: Karavodin L M , Sidell N , Woan M C , Tompkins W A
Published: January 2020

Rabbit lymphoid cells from spleen, peripheral blood, and peritoneal cavity lacked killer (K)-cell activity against cell lines of rabbit and human origin, including virus-infected human tumor cells. This lack of activity was not affected by antibody concentration, source of antibodies, effector/target cell ratio, or length of assay. Rabbit leukocytes, however, were capable of lysing antibody-coated chicken erythrocytes. Hamster leukocytes, serving as a known source of K cells, mediated antibody-dependent cellular cytotoxicity against all targets. EA-rosette assays and mixed effector cell competition tests suggested a deficiency in rabbit K-cell activity which is not a result of an inherent lack of Fc receptor-positive cells or of some suppressor mechanism operating in the rabbit cell populations. Our data support the concept that antibody-dependent cellular cytotoxicity may not be a significant in vivo immune mechanism in certain species.
Polymyxin B suppresses the endotoxin inhibition of concanavalin a-mediated erythrocyte agglutination
Authors: Warren J R
Published: January 2020

The lectin agglutinability of human erythrocytes has been utilized to examine interactions of gram-negative endotoxin with mammalian cell plasma membranes. Erythrocytes treated in buffer with Escherichia coli 0127:B8 lipopolysaccharide (LPS) or Salmonella minnesota Re595 glycolipid for 1 h became resistant to agglutination by the lectin concanavalin A (ConA) in buffer free of LPS or glycolipid. Polymyxin B, a cationic cyclic lipopeptide which specifically binds to the lipid A toxophore, was tested for possible effects on the LPS and glycolipid inhibition of Con A erythrocyte agglutination. The presence of polymyxin B during the initial 1-h treatment with LPS or glycolipid blocked the ability of the endotoxins to render erythrocytes refractory to agglutination by ConA. Inhibition by polymyxin B was stoichiometric, and in repeated experiments, LPS was completely suppressed in the hemagglutination assay at a polymyxin B:LPS weight ratio of 1:4.1 (increasing polymyxin concentration, constant LPS concentration) and 1:5.1 (constant polymyxin concentration, increasing LPS concentration). These stoichiometry values are similar to values obtained for inhibition by polymyxin B of LPS lymphoid cell activation. It was concluded, therefore, that endotoxin inhibition of ConA erythrocyte agglutination reflects interactions of erythrocyte membranes with the lipid A region of endotoxin. In addition, the stoichiometry of polymyxin B inhibition suggests a similar extent of lipid A-dependent LPS interaction with erythrocytes and lymphoid cells.
Comparison of bacterial and fungal adherence to vaginal exfoliated epithelial cells and human vaginal epithelial tissue culture cells
Authors: Sobel J D , Myers P , Levison M E , Kaye D
Published: January 2020

The adherence of four bacterial species and Candida albicans to a new in vitro tissue culture model of human vaginal stratified squamous epithelium was investigated and compared with in vitro adherence to vaginal exfoliated cells. Gardnerella vaginalis, group B streptococci, Lactobacillus sp., and C. albicans adhered well to both exfoliated and tissue culture cells. Similarly, a piliated fecal isolate of Escherichia coli, but not a nonpiliated vaginal isolate of E. coli, adhered well to both cell types. Adherence of the piliated E. coli was markedly inhibited by preincubation of bacteria with D-mannose. No inhibition of adherence by D-mannose of G. vaginalis, nonpiliated E. coli, and C. albicans was demonstrated. Scanning electron microscopy of tissue cultures showed nonuniform distribution of adherent microorganisms with diminished adherence in areas of active mitosis and proliferation and increased adherence to mature flat cells, often in the process of desquamation.
Antigenic Analysis of the Major Outer Membrane Protein of
Chlamydia
spp
Authors: Caldwell Harlan D. , Schachter Julius
Published: January 2020

The major outer membrane proteins (MOMPs) of several
Chlamydia trachomatis
serotypes (B, D, G, H, and L2) and of the
C. psittaci
meningopneumonitis strain were purified by preparatory sodium dodecyl sulfate-(SDS)-polyacrylamide gel electrophoresis. The isolated SDS-polypeptide complexes, which varied in their apparent subunit molecular weights, were used as immunogens to raise hyperimmune rabbit antisera. The specificities of these antisera were determined both by rocket immunoelectrophoresis with the soluble SDS-polypeptide complex as antigen and by micro-immunofluorescence with whole organisms. By rocket immunoelectrophoresis, each of the soluble
C. trachomatis
MOMPs was immunologically related; however, no immunological cross-reactions occurred with the
C. psittaci
meningopneumonitis polypeptide, indicating that the MOMPs are antigenically distinct among members of these two chlamydial species. The same antisera were highly reactive with intact organisms by micro-immunfluorescence, demonstrating that at least some of the antibodies raised with SDS-polypeptide complexes reacted with native antigenic sites of these surface proteins. By micro-immunofluorescence, anti-MOMP sera remained species specific; but, unlike the results observed by rocket immunoelectrophoresis, distinct differences in the reactivity and specificity of these antisera were observed among
C. trachomatis
serotypes.
C. trachomatis
isolates were separated into two distinct serogroups on the basis of their reactivity with anti-MOMP sera. B complex organisms (B, Ba, D, E, F, G, K, L1, L2, and L3) all reacted strongly with anti-MOMP sera of the B, D, G, and L2 serotypes. In contrast, these same antisera were poorly reactive with the C complex serotypes A, C, H, I, and J. Anti-H MOMP serum was the most serospecific, since high-antibody titers were found only against the homologous H serotype organism. These findings indicate that MOMPs of different strains of
C. trachomatis
are antigenically complex and that antigenic heterogeneity exists among the surface-exposed portions of the protein.
Characterization of an antigenically distinct porcine rotavirus
Authors: Bridger J C , Clarke I N , McCrae M A
Published: January 2020

A porcine virus with rotavirus morphology, which was antigenically unrelated to previously described rotaviruses, is described. Particles with an outer capsid layer measured 75 nm and those lacking the outer layer were 63 nm in diameter. Particles which resembled cores were also identified. The virus was shown to be antigenically distinct from other rotaviruses as judged by immunofluorescence and immune electron microscopy, and it failed to protect piglets from challenge with porcine rotavirus. Analysis of the genome indicated that it was composed of 11 segments of double-stranded RNA with the same overall size range as other rotaviruses but with an unusual segment pattern.
Involvement of a plasmid in the invasive ability of Shigella flexneri
Authors: Sansonetti P J , Kopecko D J , Formal S B
Published: January 2020

Representative Shigella flexneri strains were studied to determine whether plasmids are involved in their virulence. All invasive S. flexneri strains, irrespective of serotype, were found to harbor a large plasmid of approximately 140 megadaltons in size, although some strains carried additional plasmid species. Spontaneous variants of strains of serotypes 1, 2, and 5 had lost this 140-megadalton plasmid and had concomitantly become avirulent, i.e., could neither invade HeLa cell monolayers nor produced keratoconjunctivitis in guinea pigs. To monitor plasmid transfer, the 140-megadalton plasmid of strain M90T (serotype 5) was tagged with the kanamycin resistance transposon Tn5. This tagged plasmid, pWR110, was not self-transmissible, but was mobilized by one of several different conjugative plasmids into avirulent derivatives of the heterologous serotypes 1 and 2 which had lost the comparable large plasmid. Transconjugants of both serotypes which had received pWR110 regained virulence. These data directly demonstrate that this large S. flexneri plasmid encodes or regulates some function(s) required for epithelial cell penetration.