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1.
Vet Microbiol ; 286: 109895, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37890432

ABSTRACT

First identified in 2002, diphtheritic stomatitis (DS) is a devastating disease affecting yellow-eyed penguins (Megadyptes antipodes, or hoiho in te reo Maori). The disease is associated with oral lesions in chicks and has caused significant morbidity and mortality. DS is widespread among yellow-eyed penguin chicks on mainland New Zealand yet appears to be absent from the subantarctic population. Corynebacterium spp. have previously been suspected as causative agents yet, due to inconsistent cultures and inconclusive pathogenicity, their role in DS is unclear. Herein, we used a metatranscriptomic approach to identify potential causative agents of DS by revealing the presence and abundance of all viruses, bacteria, fungi and protozoa - together, the infectome. Oral and cloacal swab samples were collected from presymptomatic, symptomatic and recovered chicks along with a control group of healthy adults. Two novel viruses from the Picornaviridae were identified, one of which - yellow-eyed penguin megrivirus - was highly abundant in chicks irrespective of health status but not detected in healthy adults. Tissue from biopsied oral lesions also tested positive for the novel megrivirus upon PCR. We found no overall clustering among bacteria, protozoa and fungi communities at the genus level across samples, although Paraclostridium bifermentans was significantly more abundant in oral microbiota of symptomatic chicks compared to other groups. The detection of a novel and highly abundant megrivirus has sparked a new line of inquiry to investigate its potential association with DS.


Subject(s)
Picornaviridae , Spheniscidae , Stomatitis , Animals , Corynebacterium , Spheniscidae/microbiology , Spheniscidae/virology , Stomatitis/veterinary
2.
J Anim Ecol ; 90(7): 1776-1786, 2021 07.
Article in English | MEDLINE | ID: mdl-33844849

ABSTRACT

Urbanisation and anthropogenic alteration of ecosystems has led to conflict between humans and wildlife. Such conflict is often observed in apex predators. Although human-wildlife conflict has been extensively studied, male/female differences in behaviour are rarely considered. We investigated male/female differences in foraging behaviour of the predatory/scavenging brown skua Catharacta antarctica lonnbergi breeding on a New Zealand island nature reserve in proximity to farmland. These skuas are subject to culling, when perceived as a threat to livestock. As part of a long-term ecological study, we used high-resolution Global Positioning System (GPS) devices to characterise the space-use of foraging brown skuas. We also analysed stable isotopes of carbon (δ13 C) and nitrogen (δ15 N) from modern and archived blood samples to investigate possible changes in diet over the past ~30 years. Analysis of 100 GPS tracks collected from 2014 to 2016 demonstrated that males and females consistently visited different habitats. Males spent most of their time close to their breeding territory on the island nature reserve and females frequently visited a farmed island approximately two kilometres away. Consistent with this finding, we show that male and female skuas also differed markedly in their diets: males specialised on burrow-nesting white-faced storm petrels Pelagodroma marina (80%) with only a small proportion of sheep remains Ovis aries (<6%) contributing to their diet. In contrast, female diet comprised 27% white-faced storm petrels, other seabirds (18%) and a relatively large proportion of sheep remains (47%). Further, our data (186 blood samples from 122 individuals) show that this male/female difference in diet has persisted at least since 1987. Because females fed disproportionally on sheep remains, they may be more vulnerable to being culled by farmers. Importantly, our case study suggests that intersexual differences in diet and foraging patterns can have major implications for the reproduction and survival of apex predators that interact with farming. We strongly suggest that intersexual differences in behaviour should be considered when investigating human-wildlife conflicts.


Subject(s)
Charadriiformes , Ecosystem , Animals , Animals, Wild , Birds , Female , Humans , Male , New Zealand , Sheep
3.
J Immunol ; 179(4): 2477-84, 2007 Aug 15.
Article in English | MEDLINE | ID: mdl-17675509

ABSTRACT

The bactericidal/permeability-increasing protein (BPI) is thought to play an important role in killing and clearance of Gram-negative bacteria and the neutralization of endotoxin. A possible role for BPI in clearance of cell-free endotoxin has also been suggested based on studies with purified endotoxin aggregates and blood monocytes. Because the interaction of BPI with cell-free endotoxin, during infection, occurs mainly in tissue and most likely in the form of shed bacterial outer membrane vesicles ("blebs"), we examined the effect of BPI on interactions of metabolically labeled ([(14)C]-acetate) blebs purified from Neisseria meningitidis serogroup B with either human monocyte-derived macrophages or monocyte-derived dendritic cells (MDDC). BPI produced a dose-dependent increase (up to 3-fold) in delivery of (14)C-labeled blebs to MDDC, but not to monocyte-derived macrophages in the presence or absence of serum. Both, fluorescently labeled blebs and BPI were internalized by MDDC under these conditions. The closely related LPS-binding protein, in contrast to BPI, did not increase association of the blebs with MDDC. BPI-enhanced delivery of the blebs to MDDC did not increase cell activation but permitted CD14-dependent signaling by the blebs as measured by changes in MDDC morphology, surface expression of CD80, CD83, CD86, and MHC class II and secretion of IL-8, RANTES, and IP-10. These findings suggest a novel role of BPI in the interaction of bacterial outer membrane vesicles with dendritic cells that may help link innate immune recognition of endotoxin to Ag delivery and presentation.


Subject(s)
Antigen Presentation/immunology , Antigens, Bacterial/immunology , Antimicrobial Cationic Peptides/immunology , Blood Proteins/immunology , Cell Membrane/immunology , Dendritic Cells/immunology , Immunity, Innate/immunology , Macrophages/immunology , Membrane Proteins/immunology , Neisseria meningitidis, Serogroup B/immunology , Acute-Phase Proteins/immunology , Acute-Phase Proteins/metabolism , Antigens, Bacterial/metabolism , Antigens, CD/immunology , Antigens, CD/metabolism , Antimicrobial Cationic Peptides/metabolism , Biological Transport, Active/immunology , Blood Proteins/metabolism , Carrier Proteins/immunology , Carrier Proteins/metabolism , Cell Membrane/metabolism , Cells, Cultured , Chemokines/immunology , Chemokines/metabolism , Dendritic Cells/metabolism , Endotoxins/immunology , Endotoxins/metabolism , Histocompatibility Antigens Class II/metabolism , Humans , Macrophages/metabolism , Membrane Glycoproteins/immunology , Membrane Glycoproteins/metabolism , Membrane Proteins/metabolism , Protein Binding/immunology , Signal Transduction/immunology
4.
Clin Chim Acta ; 384(1-2): 12-23, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17678885

ABSTRACT

Gram-negative bacteria (GNB) and their endotoxin present a constant environmental challenge. Endotoxins can potently signal mobilization of host defenses against invading GNB but also potentially induce severe pathophysiology, necessitating controlled initiation and resolution of endotoxin-induced inflammation to maintain host integrity. The bactericidal/permeability-increasing protein (BPI) is a pluripotent protein expressed, in humans, mainly neutrophils. BPI exhibits strong antimicrobial activity against GNB and potent endotoxin-neutralizing activity. BPI mobilized with neutrophils in response to invading GNB can promote intracellular and extracellular bacterial killing, endotoxin neutralization and clearance, and delivery of GNB outer membrane antigens to dendritic cells. Tissue expression by dermal fibroblasts and epithelia could further amplify local levels of BPI and local interaction with GNB and endotoxin, helping to constrain local tissue infection and inflammation and prevent systemic infection and systemic inflammation. This review article focuses on the structural and functional properties of BPI with respect to its contribution to host defense during GNB infections and endotoxin-induced inflammation and the genesis of autoantibodies against BPI that can blunt BPI activity and potentially contribute to chronic inflammatory disease.


Subject(s)
Antimicrobial Cationic Peptides/chemistry , Antimicrobial Cationic Peptides/metabolism , Autoimmunity , Blood Proteins/chemistry , Blood Proteins/metabolism , Gram-Negative Bacterial Infections/immunology , Inflammation/immunology , Membrane Proteins/chemistry , Membrane Proteins/metabolism , Antimicrobial Cationic Peptides/analysis , Blood Proteins/analysis , Humans , Membrane Proteins/analysis
5.
Autoimmun Rev ; 6(4): 223-7, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17317612

ABSTRACT

Antineutrophil cytoplasmic autoantibodies against the neutrophil granule bactericidal/permeability increasing protein (BPI-ANCA) have been found in diseases of different etiologies, such as cystic fibrosis, TAP deficiency or inflammatory bowel diseases. A common feature of these conditions is the chronic or profuse exposure of the host to Gram-negative bacteria and their endotoxin. BPI plays an important role in killing Gram-negative bacteria as well as neutralization and disposal of their endotoxin. During this interaction BPI can direct the delivery of complexes which contain endotoxin and bacterial outer membrane proteins to antigen presenting cells. Based on recent findings on how complexes of endotoxin and protein antigens need to be processed by dendritic cells in order to become presented on MHC class II molecules, a model can be proposed how Gram-negative bacterial infections can be linked to the generation of autoantibodies against BPI.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/immunology , Antimicrobial Cationic Peptides/immunology , Autoimmunity/immunology , Blood Proteins/immunology , Gram-Negative Bacterial Infections/immunology , Membrane Proteins/immunology , Animals , Endotoxins/immunology , Gram-Negative Bacteria/immunology , Humans
6.
MMW Fortschr Med ; Spec no. 2: 42, 44-6, 48, 2006 May 15.
Article in German | MEDLINE | ID: mdl-20104714

ABSTRACT

The symptoms associated with somatoform vertigos take on many forms and often appear to be organic in origin. Only a complete medical history in connection with a clinical neurootological examination and psychiatric/psychosomatic exploration can differentiate between organic (e.g., vestibular) and somatoform vertigos. The patients must be informed about this disorder so that the symptoms are taken seriously. Even though they cannot be ascribed to an organic impairment, the symptoms are still clinically significant. Somatoform vertigo is primarily treated with behavior therapy (if necessary, combined with supportive psychopharmacotherapy). Many patients have good prognosis, particularly when therapy is initiated early.


Subject(s)
Anxiety Disorders , Phobic Disorders , Somatoform Disorders , Vertigo/psychology , Anxiety Disorders/diagnosis , Behavior Therapy , Chronic Disease , Diagnosis, Differential , Family Practice , Humans , Medical History Taking , Phobic Disorders/diagnosis , Prognosis , Psychotherapy , Somatoform Disorders/diagnosis , Time Factors , Vertigo/diagnosis , Vertigo/physiopathology , Vertigo/therapy
8.
Pediatr Pulmonol ; 37(2): 158-64, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14730661

ABSTRACT

Gram-negative bacterial lung infections and chronic bacterial colonization are major threats for pediatric cystic fibrosis (CF) patients. Besides impeded mucociliary clearance, other mechanisms that contribute to increased susceptibility to infections are presumed. The bactericidal/permeability-increasing protein (BPI), which is delivered by neutrophil granulocytes and mucosal epithelial cells, is one of the most potent innate antibiotics against Gram-negative bacteria and endotoxin. Antineutrophil cytoplasmic autoantibodies against BPI (BPI-ANCA) have been found in up to 90% of CF patients, and titers correlated inversely with lung function parameters. As major pulmonary damage is mediated by Gram-negative bacteria and their products, the question was raised as to whether BPI-ANCA can inhibit the antibiotic function of BPI in these patients. Sera of 23 pediatric CF patients were analyzed for the presence of BPI-ANCA by indirect immunofluorescence, ELISA, epitope mapping, and Western blotting. Patients' IgG were tested in a bacterial growth inhibition assay with recombinant BPI (rBPI) and an amino-terminal fragment of BPI (rBPI(21)) that retains antibiotic activity for inhibition of the antibiotic function of BPI against E. coli DH5alpha in vitro. BPI was recognized by 21 of 23 patients' sera in our detection assays. Thirteen of 23 patients' BPI-ANCA (56%) could inhibit the antibiotic function in vitro. Moreover, epitope mapping over the whole BPI sequence revealed that more patients' BPI-ANCA recognize the amino-terminal part of BPI than can be detected by ELISA. Thus, in pediatric CF patients, BPI-ANCA may contribute to diminished bacterial clearance by inhibiting the antibiotic function of BPI.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/immunology , Blood Proteins/immunology , Cystic Fibrosis/immunology , Escherichia coli/immunology , Membrane Proteins , Adolescent , Adult , Antibodies, Antineutrophil Cytoplasmic/metabolism , Antimicrobial Cationic Peptides , Blood Proteins/metabolism , Child , Child, Preschool , Cystic Fibrosis/metabolism , Cystic Fibrosis/microbiology , Enzyme-Linked Immunosorbent Assay , Epitope Mapping , Female , Fluorescent Antibody Technique, Indirect , Humans , Male
9.
Inflamm Bowel Dis ; 10(6): 763-70, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15626895

ABSTRACT

Bactericidal/permeability-increasing protein (BPI) is an antineutrophil cytoplasmic autoantibody (ANCA) target antigen in inflammatory bowel disease (IBD). The aim of this study was to characterize binding regions of BPI-autoantibodies and to analyze their ability to block the antibiotic effect of BPI. Sera of 24 ulcerative colitis and Crohn's disease patients were examined in indirect immuno-fluorescence, ANCA enzyme-linked immunosorbent assay (ELISA), and by epitope mapping with 13mer peptides and Western blot for presence of BPI-autoantibodies. IgG preparations were used to determine inhibition of BPI's antimicrobial function by BPI-autoantibodies in a bacterial growth inhibition assay. BPI-autoantibodies were detected by ELISA in 18/24 patients. Epitope mapping and western blotting revealed an additional 3 patients with BPI-autoantibodies. IgG preparations of all patients with Crohn's disease and 9 of 12 ulcerative colitis patients could inhibit the antibiotic function of BPI in vitro as compared with healthy control subjects. Inhibiting BPI-autoantibodies correlated with extraintestinal manifestations, peripheral blood leukocyte counts, and anemia. BPI-autoantibodies recognizing the N-terminal portion were associated with greater mucosal damage and intestinal extent of disease. BPI is a frequent target antigen of autoantibodies in ulcerative colitis and Crohn's disease. Inhibition of the antibiotic function mediated by the N-terminal region of BPI by these autoantibodies may contribute to a proinflammatory environment in IBD patients.


Subject(s)
Antibodies, Antineutrophil Cytoplasmic/immunology , Blood Proteins/immunology , Colitis, Ulcerative/immunology , Crohn Disease/immunology , Membrane Proteins/immunology , Adolescent , Adult , Anti-Bacterial Agents/immunology , Antimicrobial Cationic Peptides , Blood Bactericidal Activity/immunology , Blotting, Western , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Escherichia coli/immunology , Female , Humans , Male , Middle Aged
10.
Clin Diagn Lab Immunol ; 10(3): 473-5, 2003 May.
Article in English | MEDLINE | ID: mdl-12738651

ABSTRACT

The bactericidal/permeability-increasing protein (BPI) is an antibiotic- and endotoxin-neutralizing protein of granulocytes and epithelial cells. Constitutive expression of BPI, which increases upon interleukin 4 stimulation, by human dermal fibroblast was demonstrated, suggesting an important role of BPI in gram-negative bacterial clearance and a dampened response to endotoxin in the skin.


Subject(s)
Blood Proteins/biosynthesis , Fibroblasts/metabolism , Interleukin-4/pharmacology , Membrane Proteins , Antimicrobial Cationic Peptides , Blood Proteins/genetics , Blood Proteins/immunology , Endotoxins/pharmacology , Fibroblasts/microbiology , Humans , RNA, Messenger/analysis , Skin/cytology , Up-Regulation/drug effects
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