bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of Anionic Antimicrobial Peptides in Ovine Bronchoalveolar Lavage Fluid and Respiratory Epithelium
Authors: Brogden Kim A. , Ackermann Mark , Huttner Kenneth M. 
Published: December 2019

ABSTRACT
Three small antimicrobial anionic peptides (AP) were originally isolated from an ovine pulmonary surfactant. However, their presence in bronchoalveolar lavage (BAL) fluid and tissues of the respiratory tract is unknown. In this study, we made affinity-purified rabbit polyclonal and mouse monoclonal antibodies to synthetic H-DDDDDDD-OH. Antibody specificity was assessed by a competitive enzyme-linked immunosorbent assay (ELISA), and the exact epitope binding sites were determined with analog peptides synthesized on derivatized cellulose. These antibodies were used to detect AP in BAL fluid by ELISA and in respiratory tissues by Western blot analysis and immunocytochemistry. BAL fluid from 25 sheep contained 0.83 ± 0.33 mM AP (mean ± standard deviation; range, 0.10 to 1.59 mM) and was antimicrobial. The presence of AP in BAL fluid was confirmed by reverse-phase high-pressure liquid chromatography fractionation followed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry on those fractions which were positive by competitive ELISA and demonstrated antimicrobial activity. In Western blots, polyclonal antibody PAB96-1 and monoclonal antibody 1G9-1C2 (5.0 μg/ml) detected four bands in solubilized turbinate and tracheal epithelial cells (53.7, 31.2, 28.0, and 25.7 kDa) and five bands in lung homogenates (53.5, 37.1, 31.2, 28.0, and 25.7 kDa). Only a single band was seen in solubilized liver and small-intestine homogenates, and no bands were seen in blots containing BAL fluid, albumin, or kidney or spleen homogenates. In pulmonary-tissue sections, both antibodies PAB96-1 and 1G9-1C2 identified accumulated protein in the apical cytoplasm of the bronchial and bronchiolar epithelia, in the cytoplasm of pulmonary endothelial cells, and in an occasional alveolar macrophage. As a first step in identifying a candidate AP precursor gene(s), degenerate oligonucleotides representing all possible coding combinations for H-GADDDDD-OH and H-DDDDDDD-OH were synthesized and used to probe Southern blots of sheep genomic DNA. Following low-stringency washes and a 2-day exposure, strongly hybridizing bands could be identified. One degenerate oligonucleotide, SH87, was used as a hybridization probe to screen a sheep phage genomic library. Two independent phage contained the H-GADDDDD-OH coding sequence as part of a larger predicted protein. AP may originate as part of an intracellular precursor protein, with multistep processing leading to the release of the heptapeptide into mucosal secretions. There it may interact with other innate pulmonary defenses to prevent microbial infection.
Actinobacillus actinomycetemcomitansToxin Induces Both Cell Cycle Arrest in the G2/M Phase and Apoptosis
Authors: Ohguchi Masahiro , Ishisaki Akira , Okahashi Nobuo , Koide Masanori , Koseki Takeyoshi , Yamato Kenji , Noguchi Toshihide , Nishihara Tatsuji 
Published: December 2019

ABSTRACTWe found that the culture supernatant of the periodontopathic bacteriumActinobacillus actinomycetemcomitanshad a cytotoxic effect on several cell lines. In this study, we purified the toxin from the culture supernatant ofA. actinomycetemcomitansY4 by a four-step procedure: ammonium sulfate precipitation, POROS HQ/M column chromatography, polymyxin B matrix column chromatography, and Mono-Q column chromatography. The purified toxin gave two major bands of protein with molecular masses of 80 and 85 kDa upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The mechanism of cell death of the B-cell hybridoma cell line HS-72 was examined by observing changes in nuclear morphology, an increase in the proportion of fragmented DNA, and the typical ladder pattern of degraded chromosomal DNA, indicating the induction of apoptosis. Overexpression of human Bcl-2 suppressed apoptosis in HS-72 cells, indicating that the toxin fromA. actinomycetemcomitansinduces apoptosis by a Bcl-2-inhibitable mechanism. Flow cytometric analysis revealed that the toxin caused cell cycle arrest in the G2/M phase and apoptosis in HS-72 cells. In addition, aurintricarboxylic acid, a DNA endonuclease inhibitor, markedly decreased the percentage of apoptotic cells but had no effect on cell cycle arrest in the G2/M phase. Taken together, these findings suggest that the toxin fromA. actinomycetemcomitanscould mediate the development of periodontal diseases through cell cycle arrest in the G2/M phase and apoptosis in B lymphocytes of periodontal tissue.
Tumor Necrosis Factor Alpha Enhances Antifungal Activities of Polymorphonuclear and Mononuclear Phagocytes againstAspergillus fumigatus
Authors: Roilides Emmanuel , Dimitriadou-Georgiadou Anastasia , Sein Tin , Kadiltsoglou Isaac , Walsh Thomas J. 
Published: December 2019

ABSTRACTInvasive aspergillosis is a serious complication in immunocompromised patients. The effects of recombinant human tumor necrosis factor alpha (TNF-α) on antifungal activities of human neutrophils (polymorphonuclear leukocytes [PMNs]), human monocytes (MNCs), and rabbit pulmonary alveolar macrophages (PAMs) againstAspergillus fumigatuswere studied. The percentage of PMN-induced hyphal damage was increased after 30 min of incubation of PMNs with 0.1 ng of TNF-α per ml at 37°C (P= 0.043). At 0.1 to 10 ng/ml, TNF-α also increased superoxide anion (O2−) produced by PMNs in response to phorbol myristate acetate,N-formylmethionyl leucyl phenylalanine, and unopsonized hyphae (P< 0.01) but did not exert any effect on PMN phagocytosis of conidia in the presence of serum. By comparison, TNF-α induced only a slight increase in O2−production by MNCs in response to phorbol myristate acetate (P= 0.05) and no concomitant increase in the percentage of MNC-induced hyphal damage. Incubation of MNCs with TNF-α at 0.001 to 10 ng/ml for 2 days had no effect on phagocytosis or conidiocidal activity. By contrast, incubation of PAMs with TNF-α at 0.1 to 10 ng/ml for 2 days increased phagocytosis of conidia (P= 0.03). Thus, TNF-α augments the capacity of PMNs to damageAspergillushyphae, possibly through enhanced oxidative mechanisms, and increases PAM phagocytic activity against conidia. As such, TNF-α may have an important role in host defense against aspergillosis, and neutralization of its activity may be complicated by increased susceptibility to aspergillosis.
Correlation of Cecal Microflora of HLA-B27 Transgenic Rats with Inflammatory Bowel Disease
Authors: Onderdonk Andrew B. , Richardson James A. , Hammer Robert E. , Taurog Joel D. 
Published: December 2019

ABSTRACTTransgenic rats with a high level of expression of the human major histocompatibility complex class I molecule HLA-B27 develop chronic inflammatory bowel disease (IBD) and arthritis. Assessment of the cecal microflora showed a rise in numbers ofEscherichia coliandEnterococcusspp., corresponding to the presence and severity of IBD in these rats.
Lactobacilli and Streptococci Induce Interleukin-12 (IL-12), IL-18, and Gamma Interferon Production in Human Peripheral Blood Mononuclear Cells
Authors: Miettinen Minja , Matikainen Sampsa , Vuopio-Varkila Jaana , Pirhonen Jaana , Varkila Kari , Kurimoto Masashi , Julkunen Ilkka 
Published: December 2019

ABSTRACTHuman peripheral blood mononuclear cells (PBMC) were stimulated with three nonpathogenicLactobacillusstrains and with one pathogenicStreptococcus pyogenesstrain, and cytokine gene expression and protein production were analyzed. All bacteria strongly induced interleukin-1β (IL-1β), IL-6, and tumor necrosis factor alpha mRNA expression and protein production.S. pyogeneswas the most potent inducer of secretion of IL-12 and gamma interferon (IFN-γ), and two of threeLactobacillusstrains induced IL-12 and IFN-γ production. All strains induced IL-18 protein production. IL-10 and IL-4 production was induced weakly and not at all, respectively. Our data show that nonpathogenic lactobacilli and pathogenic streptococci can induce Th1 type cytokines IL-12, IL-18, and IFN-γ in human PBMC.
Susceptibility and Serologic Response of Healthy Adults to Reinfection with
Cryptosporidium parvum
Authors: Okhuysen Pablo C. , Chappell Cynthia L. , Sterling Charles R. , Jakubowski Walter , DuPont Herbert L. 
Published: December 2019

ABSTRACT

Healthy adults are susceptible to infection with small numbers of
Cryptosporidium parvum
oocysts, resulting in self-limited infection. We investigated if infection of humans with
C. parvum
is protective 1 year after primary exposure. At 1 year after a primary challenge with 30 to 10
6
oocysts, 19 healthy immunocompetent adults were rechallenged with 500 oocysts and monitored for the development of infection and/or illness. Oocyst excretion was quantitated by direct immunofluorescence with a
C. parvum
-specific monoclonal antibody, and anti-
C. parvum
antibodies in serum were detected by an enzyme-linked immunosorbent assay. Fewer subjects shed oocysts after the second exposure (3 of 19; 16%) than after the first exposure (12 of 19; 63%) (
P
< 0.005). Although the rates of diarrhea were comparable after each of the two exposures, the clinical severity as determined by the mean number of unformed stools passed was lower after reexposure (11.25 versus 8.62;
P
< 0.05). The number of anti-
Cryptosporidium
immunoglobulin G and A seroconversions increased after secondary exposure. However, the
C. parvum
serum antibody response did not correlate with the presence or absence of infection.
Antibodies and Antibody-Secreting Cells in the Female Genital Tract after Vaginal or Intranasal Immunization with Cholera Toxin B Subunit or Conjugates
Authors: Johansson Eva-Liz , Rask Carola , Fredriksson Margareta , Eriksson Kristina , Czerkinsky Cecil , Holmgren Jan 
Published: December 2019

ABSTRACTWe studied the antibody response including antibody-secreting cells (ASC) in the female genital tract of mice after mucosal immunizations with the recombinant B subunit of cholera toxin (rCTB) perorally, intraperitoneally, vaginally, and intranasally (i.n.). The strongest genital antibody responses as measured with a novel perfusion-extraction method were induced after vaginal and i.n. immunizations, and these routes also gave rise to specific immunoglobulin A (IgA) and IgG ASC in the genital mucosa. Specific ASC in the iliac lymph nodes, which drain the female genital tract, were seen only after vaginal immunization. Progesterone treatment increased the ASC response in the genital tissue after all mucosal immunizations but most markedly after vaginal immunization. We also tested rCTB as a carrier for human gamma globulin (HGG) and the effect of adding cholera toxin (CT) as an adjuvant for the induction of systemic and genital antibody responses to HGG after vaginal and i.n. immunizations. Vaginal immunizations with HGG conjugated to rCTB resulted in high levels of genital anti-HGG antibodies whether or not CT was added, while after i.n. immunization the strongest antibody response was seen with the conjugate together with CT. In summary, vaginal and i.n. immunization give rise to a specific mucosal immune response including ASC in the genital tissue, and vaginal immunization also elicits ASC in the iliac lymph nodes. We have also shown that rCTB can act as an efficient carrier for a conjugated antigen for induction of a specific antibody response in the genital tract of mice after vaginal or i.n. immunization.
Mapping of a Protective Epitope of the CopB Outer Membrane Protein ofMoraxella catarrhalis
Authors: Aebi Christoph , Cope Leslie D. , Latimer Jo L. , Thomas Sharon E. , Slaughter Clive A. , McCracken George H. , Hansen Eric J. 
Published: December 2019

ABSTRACTA monoclonal antibody (MAb) (MAb 10F3) directed against the CopB outer membrane protein ofMoraxella catarrhalispreviously was found to enhance pulmonary clearance ofM. catarrhalisin an animal model (M. Helminen, I. Maciver, J. L. Latimer, L. D. Cope, G. H. McCracken, Jr., and E. J. Hansen, Infect. Immun. 61:2003–2010, 1993). In the present study, this same MAb was shown to exert complement-dependent bactericidal activity against this pathogen in vitro. Nucleotide sequence analysis of thecopBgene from two MAb 10F3-reactive and two MAb 10F3-unreactive strains ofM. catarrhalisrevealed that the deduced amino acid sequences of these four CopB proteins were at least 90% identical. Comparison of the amino acid sequences of these proteins allowed localization of possible MAb 10F3 binding sites to five relatively small regions of the CopB protein fromM. catarrhalisO35E. When five synthetic peptides representing these regions were tested for their ability to bind MAb 10F3 in a direct enzyme-linked immunosorbent assay system, an oligopeptide containing 26 amino acids was shown to bind this MAb. The actual binding region for MAb 10F3 was localized further through the use of overlapping decapeptides that spanned this 26-mer. A fusion protein containing the same 26-mer readily bound MAb 10F3 and was used to immunize mice. The resultant antiserum contained antibodies that reacted with the CopB protein of the homologousM. catarrhalisstrain in Western blot analysis and bound to the surface of both homologous and heterologous strains ofM. catarrhalis.
The Role of Sialic Acid in Opsonin-Dependent and Opsonin-Independent Adhesion ofListeria monocytogenesto Murine Peritoneal Macrophages
Authors: Maganti Srinivas , Pierce Marcia M. , Hoffmaster Alex , Rodgers Frank G. 
Published: December 2019

ABSTRACTThe adhesion of listeriae to host cells employs mechanisms which are complex and not well understood.Listeria monocytogenesis a facultative intracellular pathogen responsible for meningoencephalitis, septicemia, and abortion in susceptible and immunocompromised individuals. Subsequent to colonization and penetration of the gut epithelium, the organism attaches to resident macrophages and replicates intracellularly, thus evading the humoral immune system of the infected host. The focus of these studies was to investigate the attachment of the organism to murine peritoneal macrophages in an opsonin-dependent and opsonin-independent fashion. Assessment of competitive binding experiments by immunofluorescence and enzyme-linked immunosorbent assays showed that adhesion of the organism to macrophages in the presence or absence of opsonins was inhibited (90%) byN-acetylneuraminic acid (NAcNeu). In addition, the lectin fromMaackia amurensis, with affinity for NAcNeu-α(2,3)galactose, blocked binding ofL. monocytogenesto host cells. Oxidation of the surface carbohydrates on the organism by using sodium metaperiodate resulted in a dose-dependent reduction (up to 98%) in adherence to macrophages. Monoclonal antibody to complement receptor 3 did not prevent listeriae from binding to mouse macrophages or from replicating within the infected cells whether or not normal mouse serum was present. Based on our results, we propose the involvement of NAcNeu, a member of the sialic acid group, in the attachment ofL. monocytogenesto permissive murine macrophages.
Therapeutic Effects of Nitric Oxide Inhibition during Experimental Fecal Peritonitis: Role of Interleukin-10 and Monocyte Chemoattractant Protein 1
Authors: Hogaboam Cory M. , Steinhauser Matthew L. , Schock Harold , Lukacs Nicholas , Strieter Robert M. , Standiford Theodore , Kunkel Steven L. 
Published: December 2019

ABSTRACTThis study demonstrates that the therapeutic effect of a nitric oxide inhibitor in a murine model of fecal peritonitis is mediated in part by increased levels of interleukin-10 (IL-10) and monocyte chemoattractant protein 1 (MCP-1). Female CD1 mice were subjected to cecal ligation and puncture (CLP) with a 21-gauge needle and, immediately following surgery, were injected intraperitoneally with saline,NG-nitro-l-arginine methyl ester (l-NAME; 8 mg/kg), orNG-nitro-d-arginine methyl ester (d-NAME; 8 mg/kg). At 96 h after surgery and drug treatment, 20% of mice that receivedd-NAME had survived whereas 60% of mice that receivedl-NAME were alive. To elucidate the effect ofl-NAME treatment on chemokine and cytokine production during fecal peritonitis, the levels of macrophage inflammatory protein 2 (MIP-2), IL-10, and MCP-1 were measured in peritoneal washings from additional groups of mice 24 h after the CLP surgery. Peritoneal fluids froml-NAME-treated mice contained significantly higher levels of IL-10 and MCP-1 than did those fromd-NAME-treated mice. To elucidate the effect of nitric oxide inhibition on potential cellular sources of IL-10 and MCP-1 in the CLP model, cultured alveolar and peritoneal macrophages were activated with bacterial lipopolysaccharide in the presence ofl-NAME; these macrophages produced significantly more MCP-1 than did similarly activated macrophages in the presence ofd-NAME. In the CLP surgery model, immunoneutralization of IL-10 alone or IL-10 and MCP-1 together with polyclonal antibodies prior to surgery significantly reduced the survival rates inl-NAME-treated groups compared withl-NAME-treated groups that received preimmune serum. Taken together, these data demonstrate that the inhibition of nitric oxide following experimental CLP fecal peritonitis is therapeutic, in part through the modulatory effect of this treatment on the synthesis of IL-10 and MCP-1.
Comprehensive Study of the Intestinal Stage of Listeriosis in a Rat Ligated Ileal Loop System
Authors: Pron Benedicte , Boumaila Claire , Jaubert Francis , Sarnacki Sabine , Monnet Jean-Paul , Berche Patrick , Gaillard Jean-Louis 
Published: December 2019

ABSTRACT

The intestinal stage of listeriosis was studied in a rat ligated ileal loop system.
Listeria monocytogenes
translocated to deep organs with similar efficiencies after inoculation of loops with or without Peyer’s patches. Bacterial seeding of deep organs was demonstrated as early as 15 min after inoculation. It was dose dependent and nonspecific, as the
ΔinlAB
, the
Δhly
, and the
ΔactA L. monocytogenes
mutants and the nonpathogenic species,
Listeria innocua
, translocated similarly to wild-type
L. monocytogenes
strains. The levels of uptake of listeriae by Peyer’s patches and villous intestine were similar and low, 50 to 250 CFU per cm
2
of tissue. No listeria cells crossing the epithelial sheet of Peyer’s patches and villous intestine were observed by transmission electron microscopy. The lack of significant interaction of listeriae and the follicle-associated epithelium of Peyer’s patches was confirmed by scanning electron microscopy. The follicular tissue of Peyer’s patches was a preferential site of
Listeria
replication. With all doses tested, the rate of bacterial growth was 10 to 20 times higher in Peyer’s patches than in villous intestine. At early stages of Peyer’s patch infection, listeriae were observed inside mononuclear cells of the dome area. Listeriae then disseminated throughout the follicular tissue except for the germinal center. The virulence determinants
hly
and, to a lesser extent,
actA
, but not
inlAB
, were required for the completion of this process. This study suggests that Peyer’s patches are preferential sites for replication rather than for entry of
L. monocytogenes
, due to the presence of highly permissive mononuclear cells whose nature remains to be defined.
Protection againstMycobacterium tuberculosisInfection by CD8+T Cells Requires the Production of Gamma Interferon
Authors: Tascon Ricardo E. , Stavropoulos Evangelos , Lukacs Katalin V. , Colston M. Joseph 
Published: December 2019

ABSTRACTThe role of CD8 T cells in controllingMycobacterium tuberculosisinfections in mice was confirmed by comparing the levels of growth of the organism in control, major histocompatibility complex class II knockout, and athymic mice and by transferring T-cell populations into athymic mice. By using donor mice which were incapable of making gamma interferon (IFN-γ), it was shown that IFN-γ production was essential for CD8 cell mediation of protective immunity againstM. tuberculosis.
Enterococcus faecalis
Localization in Experimental Endophthalmitis: Role of Plasmid-Encoded Aggregation Substance
Authors: Jett Bradley D. , Atkuri Rajeshwari V. , Gilmore Michael S. 
Published: December 2019

ABSTRACT

Enterococci have emerged as leading agents of nosocomial infection, yet relatively little is known about the pathogenesis of enterococcal disease. In previous studies, we developed an
Enterococcus faecalis
endophthalmitis infection model which provides unique opportunities to study the evolution of enterococcal disease by direct observation, as well as through sensitive electrophysiologic measures of organ function. The present study was designed to determine whether
E. faecalis
possesses traits that permit its attachment to mammalian tissues during infection. It was also of interest to determine whether a plasmid-encoded adhesin, aggregation substance, contributes to enterococcal localization or otherwise mediates adherence to alternate sites. These studies found that, in this model, enterococci attach to membranous structures occurring within the vitreous but that this attachment or the course or severity of disease is unaffected by the aggregation substance phenotype.
Cell-Specific Proteins Synthesized bySalmonella typhimurium
Authors: Burns-Keliher Lisa , Nickerson Cheryl A. , Morrow Brian J. , Curtiss Roy 
Published: December 2019

ABSTRACTStudies of the proteins synthesized bySalmonella typhimuriumduring growth within tissue culture cells have previously focused on a single cell type. In the present study we examine the different protein patterns exhibited byS. typhimuriumduring growth within three different cell types relevant to those it would encounter throughout the course of a natural infection, including intestinal epithelial cells (Intestine-407), macrophages (J774.A, rat bone marrow-derived macrophages, and mouse bone marrow-derived macrophages), and liver cells (NMuLi). Side-by-side comparisons reveal thatS. typhimuriumresponds to these different cellular environments with specific patterns of protein synthesis unique to each cell type. The numbers of proteins detected in each cell line are as follows: 142 proteins in Intestine-407, of which 58 appear to be unique to growth within this cell line; 413 proteins in J774.A, of which 157 appear to be unique; 260 proteins in rat bone marrow-derived macrophages, of which 40 appear to be unique; 336 proteins in mouse bone marrow-derived macrophages, of which 113 appear to be unique; and 183 proteins in NMuLi, of which 91 appear to be unique.
Expression of β-Defensin Genes in Bovine Alveolar Macrophages
Authors: Ryan Lisa K. , Rhodes Janice , Bhat Meenakshi , Diamond Gill 
Published: December 2019

ABSTRACT
Bovine alveolar macrophages (BAM) were examined for the expression of β-defensins and to determine whether their expression could be upregulated by bacterial lipopolysaccharide (LPS), as observed with β-defensins expressed in bovine tracheal epithelial cells. Four β-defensins were expressed constitutively in BAM, with bovine neutrophil β-defensin (BNBD)-4 and BNBD-5 being the most predominant. This is the first evidence of β-defensin gene expression in a mature myeloid cell. LPS had no effect on β-defensin expression in BAM, even though tumor necrosis factor alpha (TNF-α) production was induced. Nonbacterial inflammatory particles had little effect on β-defensin gene expression or TNF-α production in BAM. We hypothesize that constitutively expressed β-defensins of alveolar macrophages may have a role in lung host defense.