Mesenchymal to epithelial transition driven by canine distemper virus infection of canine histiocytic sarcoma cells contributes to a reduced cell motility in vitro.

Sarcomas especially of histiocytic origin often possess a poor prognosis and response to conventional therapies. Interestingly, tumours undergoing mesenchymal to epithelial transition (MET) are often associated with a favourable clinical outcome. This process is characterized by an increased expression of epithelial markers leading to a decreased invasion and metastatic rate. Based on the failure of conventional therapies, viral oncolysis might represent a promising alternative with canine distemper virus (CDV) as a possible candidate. This study hypothesizes that a CDV infection of canine histiocytic sarcoma cells (DH82 cells) triggers the MET process leading to a decreased cellular motility. Immunofluorescence and immunoblotting were used to investigate the expression of epithelial and mesenchymal markers followed by scratch assay and an invasion assay as functional confirmation. Furthermore, microarray data were analysed for genes associated with the MET process, invasion and angiogenesis. CDV-infected cells exhibited an increased expression of epithelial markers such as E-cadherin and cytokeratin 8 compared to controls, indicating a MET process. This was accompanied by a reduced cell motility and invasiveness. Summarized, these results suggest that CDV infection of DH82 cells triggers the MET process by an increased expression of epithelial markers resulting in a decreased cell motility in vitro.

Pneumonia due to Talaromyces marneffei in a Dog from Southern Brazil with Concomitant Canine Distemper Virus Infection.

The pathological and molecular findings associated with Talaromyces marneffei-induced pneumonia with concomitant infection by canine distemper virus (CDV) are described in a dog. The principal pathological alteration occurred in the lungs. Histopathology confirmed multifocal granulomatous pneumonia associated with numerous intralesional and intracellular septate fission cells consistent with T. marneffei. A molecular assay designed to amplify a partial fragment of the 18S rRNA gene of T. marneffei provided positive results from two fungal cultures derived from the lung. Sequencing and phylogenetic analyses confirmed the results of polymerase chain reaction (PCR). Furthermore, antigens of the CDV N protein were identified within the bronchial epithelium by immunohistochemistry and a PCR assay amplified the CDV N gene from hepatic and pulmonary fragments. Collectively, the pathological and molecular techniques confirmed a diagnosis of T. marneffei-induced pneumonia with concomitant infection by CDV. These findings represent the first description of pulmonary penicilliosis in the dog and extend the geographical niche of this emerging infectious pathogen. In this case, infection by CDV may have induced immunosuppression, which facilitated the development of pulmonary penicilliosis.

Unusual Necrotizing Encephalitis in Raccoons and Skunks Concurrently Infected With Canine Distemper Virus and Sarcocystis sp.

Canine distemper virus commonly infects free-ranging, terrestrial mesopredators throughout the United States. Due to the immunosuppressive effects of the virus, concurrent opportunistic infections are also common. Among these, secondary systemic protozoal infections have been described in a number of species. We report an unusual presentation of necrotizing encephalitis associated withSarcocystissp in four raccoons and one skunk concurrently infected with canine distemper virus. Lesions were characterized by variably sized necrotizing cavitations composed of abundant mineral admixed with inflammatory cells and protozoa.Sarcocystissp was confirmed via immunohistochemistry using a monoclonal antibody toSarcocystis neurona The pathologic changes are similar to lesions in human AIDS patients infected withToxoplasma gondii.

Infection with a Hepatozoon sp. closely related to Hepatozoon felis in a wild Pampas gray fox (Lycalopex -Pseudalopex -gymnocercus) co-infected with canine distemper virus.

A species of Hepatozoon closely related to Hepatozoon felis found in the skeletal and cardiac muscle of a wild Pampas gray fox (Lycalopex gymnocercus) is described. The fox was euthanized after showing severe incoordination. On necropsy and histopathology there was bilateral, diffuse, severe, sub-acute, necrotizing bronchointerstitial pneumonia, with intracytoplasmic and intranuclear eosinophilic inclusion bodies. Canine distemper virus was detected by immunohistochemistry in the bronchiolar epithelium, syncytial cells, alveolar macrophages and pneumocytes. The skeletal muscle and myocardium contained multiple round to oval protozoan cysts ranging from 64 µm × 75 µm to 98 µm × 122 µm, with a central eosinophilic meront-like core surrounded by concentric rings of mucinous material resembling Hepatozoon americanum cysts but smaller in size. Macrophages within rare pyogranulomas and monocytes/macrophages in adjacent sinusoidal blood vessels in the skeletal muscle contained intracytoplasmic round protozoa consistent with merozoites or developing gamonts of Hepatozoon. Hepatozoon sp. infection was confirmed by PCR of skeletal muscle and the sequenced 18S rRNA PCR product was found to be 99% identical to H. felis by BLAST analysis and deposited in GenBank as accession number HQ020489. It clustered together in the phylogenetic analysis with published H. felis sequences and separately from H. canis, H. americanum and other Hepatozoon species. However, the close relatedness of the fox Hepatozoon to H. felis does not rule out infection with a different and possibly unknown Hepatozoon species.

Unconventional wisdom about the obesity epidemic.

Diet and sedentary lifestyle, interacting with "thrifty" genes, are widely accepted as the principal cause of the current global obesity epidemic. However, a number of alternative etiologies for obesity have been proposed, including "drifty" genes, viruses, bacteria, environmental toxins, social network effects, maternal imprinting, sleep deprivation, and others. These Grand Rounds reviews the background of some of these unconventional ideas and evidence for or against their roles in the obesity epidemic.

Fatal canine distemper infection in a pack of African wild dogs in the Serengeti ecosystem, Tanzania.

In 2007, disease related mortality occurred in one African wild dog (Lycaon pictus) pack close to the north-eastern boundary of the Serengeti National Park, Tanzania. Histopathological examination of tissues from six animals revealed that the main pathologic changes comprised interstitial pneumonia and suppurative to necrotizing bronchopneumonia. Respiratory epithelial cells contained numerous eosinophilic intracytoplasmic inclusion bodies and multiple syncytial cells were found throughout the parenchymal tissue, both reacting clearly positive with antibodies against canine distemper virus (CDV) antigen. Phylogenetic analysis based on a 388 nucleotide (nt) fragment of the CDV phosphoprotein (P) gene revealed that the pack was infected with a CDV variant most closely related to Tanzanian variants, including those obtained in 1994 during a CDV epidemic in the Serengeti National Park and from captive African wild dogs in the Mkomazi Game Reserve in 2000. Phylogenetic analysis of a 335-nt fragment of the fusion (F) gene confirmed that the pack in 2007 was infected with a variant most closely related to one variant from 1994 during the epidemic in the Serengeti National Park from which a comparable fragment is available. Screening of tissue samples for concurrent infections revealed evidence of canine parvovirus, Streptococcus equi subsp. ruminatorum and Hepatozoon sp. No evidence of infection with Babesia sp. or rabies virus was found. Possible implications of concurrent infections are discussed. This is the first molecular characterisation of CDV in free-ranging African wild dogs and only the third confirmed case of fatal CDV infection in a free-ranging pack.

Combined distemper-adenoviral pneumonia in a dog.

A 3 1/2-month-old pug with oculonasal discharge and seizures was submitted for postmortem examination. Grossly, the lungs had cranioventral consolidation, and microscopically, 2 distinct types of inclusion bodies compatible with Canine distemper virus and Canine adenovirus type 2. Presence of both viruses was confirmed via immunohistochemical staining.

Simultaneous canine distemper virus, canine adenovirus type 2, and Mycoplasma cynos infection in a dog with pneumonia.

The present case is the first description of a triple infection with canine distemper virus (CDV), canine adenovirus (CAV) type 2, and Mycoplasma cynos in a dog. The 5-month-old female Miniature Pinscher was euthanized because of dyspnea, croaking lung sounds, weight loss, and lymphopenia. Pathologic examination revealed a fibrinous necrotizing pneumonia with large amphophilic intranuclear and acidophilic intracytoplasmatic inclusion bodies in different lung cells. Immunohistochemically, CDV antigen was present in lung and many other organs. In situ hybridization for detection of CAV nucleic acid showed positive signals in the lung only. Polymerase chain reaction of lung tissue and consecutive sequencing of the amplification product identified CAV type 2. Bacteriologic examination of lung tissue yielded large amounts of M cynos. This infection was confirmed by immunohistochemistry detecting abundant positive signals in the lung tissue.

Microalterations in the third eyelid gland of dogs with keratoconjunctivits sicca secondary to distemper

Keratoconjunctivitis sicca is characterized by qualitative or quantitative abnormalities in the aqueous component of the tear film and is frequent in dogs with distemper. Twenty-eight third eyelid glands of end-stage dogs that died from distemper were analyzed by light microscopy. Keratoconjunctivitis sicca was diagnosed based on ophthalmic findings regarding alterations in the ocular surface and by the Schirmer tear test. The excised glands were fixed in 10 percent buffered formalin and processed for embedding in paraffin. The blocks were cut into 4µm sections and the sections were stained with hematoxylin-eosin and Masson's trichrome. Analysis revealed tubuloacinar gland atrophy, thickening of connective tissue, and mild to intense inflammatory exudation mainly characterized by the presence of plasma cells and histiocytes and by compensatory hypertrophy of some glands. The glandular lumen was hypertrophied and contained shedded epithelial cells, polymorphonuclear cells and red blood cells, in addition to mucus.

Analisaram-se, à microscopia óptica, 28 glândulas da terceira pálpebra de cães, que morreram com cinomose. O diagnóstico de ceratoconjuntivite seca baseou-se nas alterações da superfície ocular e no teste da lágrima de Schirmer. A histologia, visibilizaram-se atrofia tubuloacina, espessamento do tecido conjuntivo e exudação inflamatória de leve a intensa com presença de plasmócitos, de histiócitos e por hipertrofia compensatória de algumas glândulas. O lume das glândulas encontrava-se hipertrofiado contendo células epiteliais descamadas, polimorfonucleares e hemácias, além de muco.

Toxoplasma gondii genotyping in a dog co-infected with distemper virus and ehrlichiosis rickettsia

This paper reports a toxoplasmosis, erhlichiosis and distemper co-infection in a dog with an exuberant neuropathological clinical picture. Primary involvement was discussed based on information collected in the analysis of the clinical case, such as neurological impairment, epidemiological data, poor immunoprophylactic scheme of the dog affected and the role of these diseases on immunosuppression. Canine distemper and ehrlichiosis were diagnosed based on epidemiologic data, clinical signs, hematological and cytological evaluation. Toxoplasma gondii was isolated and genetically characterized as Type I using restriction analysis (RFLP) with SAG-2 genes. Immunosuppression features of both dogs and human beings are discussed, as well as implications on animal and public health. This is the first report on toxoplasmosis, ehrlichiosis and distemper co-infection in a dog in Brazil, associated with genotyping determination of the T. gondii strain involved.

Este artigo relata a co-infecção tripla pelos agentes da cinomose, erliquiose e toxoplasmose em um cão com acentuado quadro clínico neuropático. Discute-se a doença primária baseando-se em dados clínicos, epidemiológicos, no protocolo imunoprofilático inadequado e no papel daquelas doenças na imunossupressão. A cinomose e a erliquiose foram diagnosticadas mediante a situação epidemiológica da região e sinais clínicos compatíveis, aliados aos achados de hemograma e citologia. Utilizando-se a análise de restrição (RFLP) com os genes SAG-2, caracterizou-se geneticamente a linhagem de Toxoplasma gondii isolada, como pertencente ao Tipo I. Discutem-se aspectos de imunossupressão, tanto em cães quanto em seres humanos, bem como suas implicações em saúde pública e animal. Este é o primeiro relato de infecção tripla pelos agentes da toxoplasmose, erliquiose e cinomose no Brasil, associado com a genotipificação da estirpe de T. gondii envolvida.

Neospora caninum infection in a free-ranging raccoon (Procyon lotor) with concurrent canine distemper virus infection.

During a canine distemper virus (CDV) outbreak in raccoons (Procyon lotor) from Cook County, Illinois, a juvenile female suffering from seizures was killed and necropsied. Gross and histologic findings of necrotizing encephalitis and proliferative bronchopneumonia were attributed to CDV infection and considered the cause of clinical signs. A section of cerebellum stained immunohistochemically for Neospora caninum revealed an approximately 40 microm diameter, round to oval cyst with a 2- to 3-microm-thick wall and filled with 1-2 microm diameter, round to oval bradyzoites. Polymerase chain reaction (PCR) results were positive for N. caninum using DNA extracted from the brain. Specific PCR for the closely related organisms Toxoplasma gondii and Hammondia heydorni yielded negative results. This case report provides histologic, immunohistochemical, and molecular evidence that raccoons are a naturally occurring intermediate host of N. caninum.

[Can obesity be infectious?]. / Czy otylosc moze byc zakazna?

Currently the presence of obesity is increasing and it has become the basic civilisation illness of our times. Up to date no attention has been paid to the possibility of etiology of infectious obesity. Recently some publications have appeared whose authors suggest a possibility of an infectious derivation of some forms of obesity. Six pathogens causing obesity in animals have been described: canine distemper virus (CDV), avian adenovirus, Borna disease virus (BDV), SMAM-1, human adenovirus Ad-36, scrapie agent, Rous-associated virus-7 (RAV-7). Among them two viruses occur in humans: human adenovirus Ad-36 and avian adenovirus SMAM-1.

Histopathology and immunohistochemistry of canine distemper virus-induced footpad hyperkeratosis (hard Pad disease) in dogs with natural canine distemper.

Hard pad disease represents an uncommon manifestation of canine distemper virus (CDV) infection with a still uncertain pathogenesis. To study the pathogenesis of this uncommon, virally induced cutaneous lesion, the footpads of 19 dogs with naturally occurring distemper were investigated for histologic changes and distribution pattern of CDV antigen. All dogs displayed clinical signs of distemper, which had lasted from 10 to 75 days. Overt digital hyperkeratosis was observed in 12 animals (group A), whereas the footpads of the remaining seven dogs appeared normal macroscopically (group B). Orthokeratotic hyperkeratosis (12/12; 100%), irregular acanthosis (11/12; 92%), thickened rete ridges (10/12; 83%), and mild mononuclear perivascular (10/ 12; 83%) and periadnexal (7/12; 58%) dermatitis were the most common findings in dogs with hard pad disease. Surprisingly, orthokeratotic hyperkeratosis (5/7; 71%), irregular acanthosis (5/7; 71%), and thickened rete ridges (4/7; 57%) were also seen in the dogs without clinical evidence of digital hyperkeratosis. CDV-specific inclusion bodies and ballooning degeneration were not observed in the footpad epidermis of the 19 dogs. Immunohis-tochemistry revealed that CDV antigen was most frequently found in the stratum spinosum and granulosum and in the epithelial cells of the eccrine sweat glands and only rarely in the basal layer. Fibroblasts, pericytes, endothelial cells, and hair follicles were also positive in some animals. Despite the obvious difference regarding the macroscopic picture, the microscopic changes were less prominent between the animal groups. The selective infection of keratinocytes in the stratum spinosum might be the key event for the development of hard pad disease in the dog.

Canine distemper virus infection with secondary Bordetella bronchiseptica pneumonia in dogs

Canine distemper virus infection and secondary Bordetella bronchiseptica pneumonia are described in mongrel dogs. Canine distemper was characterised by nonsuppurative demyelinating encephalitis with typical inclusion bodies in astrocytes. B. bronchiseptica was isolated from areas of purulent bronchopneumonia.

Isolation of Yersinia pseudotuberculosis and Listeria monocytogenes serotype 4 from a gray fox (Urocyon cinereoargenteus) with canine distemper.

In February 1993, clinical, pathological, and microbiological investigations were performed on an adult female gray fox (Urocyon cinereoargenteus) from northern Mississippi (USA). The fox had clinical signs consistent with canine distemper virus encephalitis. Eosinophilic inclusions characteristic of canine distemper virus were in the nuclei and cytoplasm of cerebral neurons and glial cells and in the cytoplasm of urinary, gastric, pancreatic and biliary epithelial cells. The liver contained multifocal microscopic nodular foci of granulomatous to pyogranulomatous inflammation and necrosis with large colonies of small Gram-negative coccobacilli. A low number of small Gram-positive bacilli were within viable-appearing Kupffer cells and hepatocytes. Yersinia pseudotuberculosis and Listeria monocytogenes serotype 4 were isolated from the liver and a mesenteric lymph node.

Multiple dental developmental abnormalities following canine distemper infection.

Multiple dental developmental abnormalities (e.g., dental impaction, partial eruption, oligodontia, enamel hypoplasia, and dentin hypoplasia) in a 10-month-old, female, Tanzanian tropical mixed-breed puppy are reported. Various permanent teeth were involved. These included impacted mandibular canine and first and third premolar teeth; a partially erupted maxillary canine tooth; oligodontia of a mandibular fourth premolar tooth; enamel hypoplasia of the maxillary and mandibular canine teeth, incisors, and premolars; and dentin hypoplasia of the maxillary incisors, maxillary premolars, and mandibular premolars. The puppy had clinical canine distemper at the age of two months and had no history of any other systemic nor generalized infection prior to the time when the dental abnormalities were observed.

Dual infection with canine distemper virus and infectious canine hepatitis virus (canine adenovirus type 1) in a dog.

A 72-day-old, female, Golden Retriever dog showed anorexia, coughing, nasal discharge, diarrhea and hematochezia, and died on the 15th clinical day. Pathological examination revealed dual infection with canine distemper virus (CDV) and canine adenovirus (CAV). CAV inclusion bodies occurred only in the liver, and biliary and respiratory system, whereas CDV inclusions were demonstrated in the visceral organs systematically. The CAV inclusions were associated with multifocal hepatocellular necrosis and edematous swelling of the wall of the gall bladder, suggesting infectious canine hepatitis virus (canine adenovirus type 1) infection.

Prevalence of Toxoplasma gondii infection in raccoons.

Serum samples from 427 raccoons (93 from Pennsylvania, 45 from New Jersey, 72 from South Carolina, 68 from Virginia, 30 from Iowa, and 119 from Ohio) were evaluated for Toxoplasma gondii antibodies in dilutions of 1:25, 1:50, and 1:500. The distribution of T gondii antibody titers was less than 1:25 for 212 raccoons (49.6%), 1:25 for 34 raccoons (7.9%), 1:50 for 117 raccoons (27.4%), and greater than or equal to 1:500 for 64 raccoons (14.9%). Tissue cysts were seen in the liver, and tachyzoites were in the brain of a raccoon with abnormal neurologic signs and concurrent infection with canine distemper virus. Organisms in the liver were stained with anti-T gondii serum, and the raccoon had a T gondii titer of 1:160 in the agglutination test.

Production of immunoglobulin G and increased antiviral antibody in cerebrospinal fluid of dogs with delayed-onset canine distemper viral encephalitis.

Sera and cerebrospinal fluid (CSF) from four dogs with delayed-onset canine distemper viral (CDV) encephalitis (old dog encephalitis) were compared with samples from dogs with acute CDV and from recently vaccinated controls. Dogs with old dog encephalitis (ODE) had elevated CSF IgG concentrations (122 micrograms/ml) compared to controls (13 micrograms/ml) without elevated CSF albumin; their CSF IgG index was significantly greater. CSF proteins banding in the alkaline region of isoelectric focusing gels were immunochemically identified as IgG. Detectable viral neutralizing antibody was present in ODE CSF, and formed a larger proportion of IgG in CSF than in serum. Serum samples containing 2 mg IgG bound to all viral polypeptides of both R252 and Onderstepoort CDV isolates by immunoblot analysis. CSF samples of ODE patients bound viral antigens when diluted to contain as little as 5-40 micrograms IgG, while patient serum could be diluted to 40-200 micrograms IgG content compared to serum IgG of 100 micrograms/ml in vaccinated controls. Serial CSF dilutions consistently bound to H and NP polypeptides at the highest dilutions, similar to the binding of serums from recently vaccinated dogs. Thus, dogs with delayed-onset CDV encephalitis have elevated concentrations of CSF IgG, much of which is virus-specific, with an antigen binding pattern similar to that of sera of recently immunized dogs.