Histopathologic, phenotypic, and molecular criteria to discriminate low-grade intestinal T-cell lymphoma in cats from lymphoplasmacytic enteritis.

BACKGROUND: Differentiation of low-grade intestinal T-cell lymphoma (LGITL) from lymphoplasmacytic enteritis (LPE) in cats is a diagnostic challenge for pathologists. OBJECTIVE: Characterize histologic, immunohistochemical, and molecular features of LGITL and LPE. ANIMALS: Forty-four client-owned cats, 22 diagnosed with LGITL and 22 with LPE. METHODS: Prospective, cohort study. Clinical suspicion of LGITL or LPE was based on persistent gastrointestinal signs, unresponsive to empirical treatments. All cats underwent a standardized diagnostic evaluation, including biopsy (preferentially full-thickness), and were diagnosed with LGITL or LPE after review of clinical, laboratory, sonographic, histologic, immunohistochemical, and clonality results. RESULTS: A monomorphic lymphocytic population (22/22, 100%) and in-depth mucosal infiltration (15/22, 68%) were hallmarks of LGITL. Epithelial patterns (nests and plaques) were significantly more frequent in LGITL (11/22, 50%) than in LPE (1/22, 5%) cases (P = .001). A CD3+ lymphocytic apical-to-basal gradient was observed in 9/22 (41%) of LGITL vs 1/22 (5%) of LPE cases (P = .004). Most LPE cases (17/18, 94%) featured marked fibrosis in the superficial part of the lamina propria. The Ki-67 20%- and 30%-thresholds discriminated between LGITL and LPE within both the epithelium (specificity >95%) and lamina propria (specificity >95%), respectively. All LGITL cases were CD3+ pSTAT3- and pSTAT5+. T-cell receptor gamma chain gene rearrangements indicated monoclonality in 86% of LGITL cases. Surprisingly, 70% of LPE cases featured monoclonality (40%) or monoclonality on a polyclonal background (30%). CONCLUSIONS AND CLINICAL IMPORTANCE: We identified new histologic, immunohistochemical, and clonality criteria to distinguish LGITL from LPE.

Feline low-grade intestinal T cell lymphoma: a unique natural model of human indolent T cell lymphoproliferative disorder of the gastrointestinal tract.

Indolent T cell lymphoproliferative disorder (LPD) of the gastrointestinal tract (GI-TLPD) is a rare human primary gastrointestinal T cell lymphoma that was recently included in the 2016 revision of the World Health Organization classification of lymphoid neoplasms. Low-grade intestinal T cell lymphoma (LGITL), an emerging disease in the domestic cat, shares a number of features with human GI-TLPD. In this prospective study, we determined whether feline LGITL might serve as a model of human GI-TLPD. We analyzed clinical, laboratory, and radiological data and performed histopathological and molecular studies on small intestinal biopsies from 22 domestic cats diagnosed with LGITL. This cancer mostly affects aging cats, is associated with nonspecific gastrointestinal tract signs, and is usually characterized by an indolent course. A histopathological analysis indicated that LGITL was mainly located in the jejunum. The small intestinal lamina propria was infiltrated by large numbers of small CD3+ T cell lymphocytes with various CD4 and CD8 expression profiles (CD4+ CD8- (4 out of 11, 36%), CD4- CD8+ (3 out of 11, 27%), and CD4- CD8- (4 out of 11, 36%)). Intraepithelial lymphocyte (IEL) counts were elevated in all cases. Ki67 was expressed in lamina propria lymphocytes and IELs at a low level (<30%). Most LGITLs were labelled by antibodies against phosphorylated STAT5, but were negative for CD56 and phosphorylated STAT3. T cell receptor gamma chain gene monoclonality was found in 86% of cases. These findings confirmed that feline LGITL shares clinical and histopathological features with human GI-TLPD. Feline LGITL may therefore constitute a relevant model of the human disease.

Cellular and molecular insights on the regulation of innate immune responses to experimental aspergillosis in chicken and turkey poults.

Across the world, many commercial poultry flocks and captive birds are threatened by infection with Aspergillus fumigatus. Susceptibility to aspergillosis varies among birds; among galliform birds specifically, morbidity and mortality rates seem to be greater in turkeys than in chickens. Little is known regarding the features of avian immune responses after inhalation of Aspergillus conidia, and to date, scarce information on inflammatory responses during aspergillosis exists. Thus, in the present study, we aimed to improve our understanding of the interactions between A. fumigatus and economically relevant galliform birds in terms of local innate immune responses. Intra-tracheal aerosolization of A. fumigatus conidia in turkey and chicken poults led to more severe clinical signs and lung lesions in turkeys, but leukocyte recovery from lung lavages was higher in chickens at 1dpi only. Interestingly, only chicken CD8+ T lymphocyte proportions increased after infection. Furthermore, the lungs of infected chickens showed an early upregulation of pro-inflammatory cytokines, including IL-1ß, IFN-γ and IL-6, whereas in turkeys, most of these cytokines showed a downregulation or a delayed upregulation. These results confirmed the importance of an early pro-inflammatory response to ensure the development of an appropriate anti-fungal immunity to avoid Aspergillus dissemination in the respiratory tract. In conclusion, we show for the first time that differences in local innate immune responses between chickens and turkeys during aspergillosis may determine the outcome of the disease.

Aspergillus fumigatus infection may cause mortality in poultry, depending on species sensitivity. This study confirms the earlier activation of chickens' pro-inflammatory effectors to control Aspergillus dissemination, whereas turkeys' immune response enables the exacerbation of lung lesions.

Thyrohyoideus muscle innervation in the horse.

OBJECTIVE: To describe the innervation of the thyrohyoideus (TH) muscle and to confirm our findings with stimulation of first cervical (C1) nerve branches. STUDY DESIGN: Ex vivo phase 1 and clinical phase 2. ANIMALS: Fourteen head and neck specimens and 17 client-owned horses. METHODS: In phase 1, the cranial nerve (CN) XII and the C1 nerve were dissected with their branches in 20 dissections were performed on 14 specimens (6 left and right side and 8 only left or right) Anatomy was noted. Samples of nerve bifurcations were collected for histological confirmation of anatomical findings. First cervical nerve branches were stimulated in horses undergoing cervical nerve graft to treat laryngeal hemiplegia. RESULTS: The nerve innervating the TH muscle arose directly from the C1 nerve in 17 of 20 dissections, from an anastomotic branch between CN XII and the C1 nerve in two of 20 dissections, and from the C1 nerve and the anastomotic branch in one of 20 dissections. No direct connection between the TH muscle and CN XII was found. Histological examination revealed that the anastomosis was composed of C1 nerve fibers passing over to CN XII. First cervical stimulation resulted in TH muscle contraction in 16 of 17 horses. CONCLUSIONS: The innervation of the TH muscle originated from the C1 nerve according to dissection, histological, and conduction studies, with variation in the branching pattern. CLINICAL SIGNIFICANCE: Care should be taken to preserve the C1 nerve during prosthetic laryngoplasty. The surgical technique for C1 nerve grafts should be reconsidered in light of these findings, along with new options to treat dorsal displacement of the soft palate..

Resumeq: A Novel Way of Monitoring Equine Diseases Through the Centralization of Necropsy Data.

The French surveillance network for causes of equine mortality (Resumeq) was created in 2015 for the qualitative surveillance of equine mortality through the centralization in a national database of necropsy data and their subsequent epidemiological analysis. It was designed to identify the causes of equine mortality, monitor their evolution over time and space, and detect emerging diseases as early as possible. Resumeq is an event-based surveillance system involving various players and structures. It is organized around a steering body, a scientific and technical support committee and a coordination unit. Different tools have been developed specifically for Resumeq. These include standardized necropsy protocols, a thesaurus for the anatomopathological terms and the causes of equine death, and an interactive web application so that network contributors can display data analysis results. The four French veterinary schools, seventeen veterinary laboratories, and ten veterinary clinics already contribute to the production and centralization of standardized data. To date, the data from around 1,000 equine necropsies have been centralized. While most deaths were located in western France, the geographic coverage is gradually improving. Data analysis allows the main causes of death to be ranked and major threats identified on a local, regional or national level. Initial results demonstrate the feasibility and benefits of this national surveillance tool. Moreover, in the future, this surveillance could take an international dimension if several countries decided to jointly capitalize on their necropsy data.

Identification of Mycobacterium genavense natural infection in a domestic ferret.

A 6-y-old neutered male ferret ( Mustela putorius furo) was presented because of a 1-mo history of progressive weight loss, chronic cough, and hair loss. On clinical examination, the animal was coughing, slightly depressed, moderately hypothermic, and had bilateral epiphora. Thoracic radiography was suggestive of severe multinodular interstitial pneumonia. Abdominal ultrasound examination revealed hepatosplenomegaly and mesenteric and pancreaticoduodenal lymphadenopathy. Fine-needle aspiration of the pancreaticoduodenal lymph node, followed by routine Romanowsky and Ziehl-Neelsen stains, revealed numerous macrophages containing myriad acid-fast bacilli, leading to identification of mycobacteriosis. Autopsy and histologic examination confirmed the presence of disseminated, poorly defined, acid-fast, bacilli-rich granulomas in the pancreaticoduodenal and mesenteric lymph nodes, intestines, and lungs. Destaining of May-Grünwald/Giemsa-stained slides with alcohol, and then restaining with Ziehl-Neelsen, revealed acid-fast rods and avoided repeat tissue sampling without affecting the Ziehl-Neelsen stain quality and cytologic features. Tissue samples were submitted for a PCR assay targeting the heat shock protein gene ( hsp65) and revealed 100% homology with Mycobacterium genavense. We emphasize the use of special stains and PCR for identification of this potential zoonotic agent.

Caloric restriction increases lifespan but affects brain integrity in grey mouse lemur primates.

The health benefits of chronic caloric restriction resulting in lifespan extension are well established in many short-lived species, but the effects in humans and other primates remain controversial. Here we report the most advanced survival data and the associated follow-up to our knowledge of age-related alterations in a cohort of grey mouse lemurs (Microcebus murinus, lemurid primate) exposed to a chronic moderate (30%) caloric restriction. Compared to control animals, caloric restriction extended lifespan by 50% (from 6.4 to 9.6 years, median survival), reduced aging-associated diseases and preserved loss of brain white matter in several brain regions. However, caloric restriction accelerated loss of grey matter throughout much of the cerebrum. Cognitive and behavioural performances were, however, not modulated by caloric restriction. Thus chronic moderate caloric restriction can extend lifespan and enhance health of a primate, but it affects brain grey matter integrity without affecting cognitive performances.

Is electroejaculation a safe procedure in cats? An endoscopic and histological prospective blinded study.

Transrectal electrostimulation is a technique used for semen collection in several animals including felids, but also in humans with spinal cord injuries and in specific cases of anejaculation. To the authors' knowledge, safety and innocuity on rectal mucosa has not yet been assessed histologically. A prospective study was performed on 10 European cats in order to determine the impact of electroejaculation on the rectal mucosa, by performing endoscopic and histological evaluation of the rectal mucosa. Endoscopic evaluation was performed before and after semen collection. Standardized biopsy specimens were collected immediately after semen collection, on the site of electrostimulation and on the proximal part of the descending colon as a control, for further double-blinded histopathological evaluation. The degree of inflammation was evaluated following the criteria from the WSAVA Gastrointestinal Standardization Group. Semen collection by electrostimulation did not induce significant histological and endoscopic lesions. Electrostimulation may therefore be considered as a safe technique to collect semen in cats.

Firewalls Prevent Systemic Dissemination of Vectors Derived from Human Adenovirus Type 5 and Suppress Production of Transgene-Encoded Antigen in a Murine Model of Oral Vaccination.

To define the bottlenecks that restrict antigen expression after oral administration of viral-vectored vaccines, we tracked vectors derived from the human adenovirus type 5 at whole body, tissue, and cellular scales throughout the digestive tract in a murine model of oral delivery. After intragastric administration of vectors encoding firefly luciferase or a model antigen, detectable levels of transgene-encoded protein or mRNA were confined to the intestine, and restricted to delimited anatomical zones. Expression of luciferase in the form of multiple small bioluminescent foci in the distal ileum, cecum, and proximal colon suggested multiple crossing points. Many foci were unassociated with visible Peyer's patches, implying that transduced cells lay in proximity to villous rather than follicle-associated epithelium, as supported by detection of transgene-encoded antigen in villous epithelial cells. Transgene-encoded mRNA but not protein was readily detected in Peyer's patches, suggesting that post-transcriptional regulation of viral gene expression might limit expression of transgene-encoded antigen in this tissue. To characterize the pathways by which the vector crossed the intestinal epithelium and encountered sentinel cells, a fluorescent-labeled vector was administered to mice by the intragastric route or inoculated into ligated intestinal loops comprising a Peyer's patch. The vector adhered selectively to microfold cells in the follicle-associated epithelium, and, after translocation to the subepithelial dome region, was captured by phagocytes that expressed CD11c and lysozyme. In conclusion, although a large number of crossing events took place throughout the intestine within and without Peyer's patches, multiple firewalls prevented systemic dissemination of vector and suppressed production of transgene-encoded protein in Peyer's patches.

Fetopathic effects of experimental Schmallenberg virus infection in pregnant goats.

Schmallenberg virus (SBV) is an emerging virus responsible for congenital malformations in the offspring of domestic ruminants. It is speculated that infection of pregnant dams may also lead to a significant number of unrecognized fetal losses during the early period of gestation. To assess the pathogenic effects of SBV infection of goats in early pregnancy, we inoculated dams at day 28 or 42 of gestation and followed the animals until day 55 of gestation. Viremia in the absence of clinical signs was detected in all virus-inoculated goats. Fetal deaths were observed in several goats infected at day 28 or 42 of gestation and were invariably associated with the presence of viral genomic RNA in the affected fetuses. Among the viable fetuses, two displayed lesions in the central nervous system (porencephaly) in the presence of viral genome and antigen. All fetuses from goats infected at day 42 and the majority of fetuses from goats infected at day 28 of gestation contained viral genomic RNA. Viral genome was widely distributed in these fetuses and their respective placentas, and infectious virus could be isolated from several organs and placentomes of the viable fetuses. Our results show that fetuses of pregnant goats are susceptible to vertical SBV infection during early pregnancy spanning at least the period between day 28 and 42 of gestation. The outcomes of experimental SBV infection assessed at day 55 of gestation include fetal mortalities, viable fetuses displaying lesions of the central nervous system, as well as viable fetuses without any detectable lesion.

Quantitative proteomics identifies host factors modulated during acute hepatitis E virus infection in the swine model.

UNLABELLED: Hepatitis E virus (HEV) causes acute enterically transmitted hepatitis. In industrialized countries, it is a zoonotic disease, with swine being the major reservoir of human HEV contamination. The occurrence and severity of the disease are variable, with clinical symptoms ranging from asymptomatic to self-limiting acute hepatitis, chronic infection, or fulminant hepatitis. In the absence of a robust cell culture system or small-animal models, the HEV life cycle and pathological process remain unclear. To characterize HEV pathogenesis and virulence mechanisms, a quantitative proteomic analysis was carried out to identify cellular factors and pathways modulated during acute infection of swine. Three groups of pigs were inoculated with three different strains of swine HEV to evaluate the possible role of viral determinants in pathogenesis. Liver samples were analyzed by a differential proteomic approach, two-dimensional difference in gel electrophoresis, and 61 modulated proteins were identified by mass spectroscopy. The results obtained show that the three HEV strains replicate similarly in swine and that they modulate several cellular pathways, suggesting that HEV impairs several cellular processes, which can account for the various types of disease expression. Several proteins, such as heterogeneous nuclear ribonucleoprotein K, apolipoprotein E, and prohibitin, known to be involved in other viral life cycles, were upregulated in HEV-infected livers. Some differences were observed between the three strains, suggesting that HEV's genetic variability may induce variations in pathogenesis. This comparative analysis of the liver proteome modulated during infection with three different strains of HEV genotype 3 provides an important basis for further investigations on the factors involved in HEV replication and the mechanism of HEV pathogenesis. IMPORTANCE: Hepatitis E virus (HEV) is responsible for acute hepatitis, with clinical symptoms ranging from asymptomatic to self-limiting acute hepatitis, chronic infection, or fulminant hepatitis. In industrialized countries, HEV is considered an emerging zoonotic disease, with swine being the principal reservoir for human contamination. The viral and cellular factors involved in the replication and/or pathogenesis of HEV are still not fully known. Here we report that several cellular pathways involved in cholesterol and lipid metabolism or cell survival were modulated during HEV infection in the swine model. Moreover, we observed a difference between the different swine strains, suggesting that HEV's genetic variability could play a role in pathogenesis. We also identified some proteins known to be involved in other viral cycles. Our study provides insight into the mechanisms modulated during HEV infection and constitutes a useful reference for future work on HEV pathogenesis and virulence.

Assessment of Aspergillus fumigatus burden in lungs of intratracheally-challenged turkeys (Meleagris gallopavo) by quantitative PCR, galactomannan enzyme immunoassay, and quantitative culture.

Aspergillus fumigatus remains a major respiratory pathogen in birds and treatment is still difficult. We challenged different groups of few-day-old turkeys via intratracheal aerosolisation with increasing concentrations (10(5) up to 10(8)) of conidia using a MicroSprayer(®) device. The fungal burden was assessed by real-time PCR, galactomannan dosage, CFU counting and histopathological evaluation in order to provide a comparison of these results within each inoculum groups. Significant mortality, occurring in the first 96h after inoculation, was only observed at the highest inoculum dose. Culture counts, GM index and qPCR results on the one hand and inoculum size on the other hand appeared to be clearly correlated. The mean fungal burden detected by qPCR was 1.3log10 units higher than the mean values obtained by CFU measurement. The new model and the markers will be used to evaluate the efficacy of antifungal treatments that could be used in poultry farms.

Type II atresia ani associated with rectovaginal fistula in a male pseudohermaphrodite kitten.

A combination of gastrointestinal and urogenital congenital abnormalities was diagnosed and surgically treated in a kitten. Physical examination, exploratory laparotomy, castration, histological examination, and cytogenetic karyotyping were utilized to determine the true gender of the kitten. The kitten was confirmed to be a male (38 XY) pseudohermaphrodite with Type II atresia ani and rectovaginal fistula.

Atrésie anale associée à une fistule recto-vaginale chez un chaton male pseudohermaphrodite. Une combinaison d'anomalies congénitales gastro-intestinales et uro-génitales a été diagnostiquée et traitée chirurgicalement chez un chaton. L'examen clinique, une laparotomie exploratrice, la castration avec examen histologique des testicules ainsi qu'un caryotypage ont été réalisés pour déterminer le véritable sexe de l'animal. Il a été confirmé que le chaton était un male (38 XY) pseudohermaphrodite avec atrésie anale de Type II et fistule rectovaginale.(Traduit par les auteurs).

Skin fragility syndrome in a cat with multicentric follicular lymphoma.

An 11-year-old, spayed female domestic shorthair cat was presented for a right flank wound. On clinical examination, a single non-painful skin tear lesion with irregular edges was detected. During the examination, star-shaped cigarette paper-like skin lesions appeared spontaneously. An abdominal mass was also palpated. Feline skin fragility syndrome (FSFS) was suspected and a multicentric lymphoma was diagnosed by fine needle aspiration. The cat's condition declined and it died spontaneously. Post-mortem examination confirmed the diagnosis of lymphoma. Neoplastic lymphocytes were not observed in the skin. Histological analysis of the skin was consistent with the morphological aspects of FSFS. A possible direct link between the two conditions remains a matter of speculation, but this case report provides the first description of FSFS associated with multicentric follicular lymphoma. Thus, multicentric follicular lymphoma should be considered as a differential diagnosis in cats presenting with FSFS.

Assessment of Aspergillus fumigatus pathogenicity in aerosol-challenged chickens (Gallus gallus) belonging to two lineages.

Infection due to the mold Aspergillus fumigatus remains a common and life-threatening infection in many animals, especially birds. Animal models are still required to better understand the physiopathology of infection and evaluate diagnostic tools and treatment procedures. The aim of the present study was to assess the pathogenicity of A. fumigatus in two lineages of chicken (Gallus gallus): SPF White Leghorn PA12 layers and conventional JA657 broilers. Four-day-old birds were experimentally infected in an inhalation chamber in order to reproduce a "natural" contamination and to obtain a large repartition of conidia into the respiratory tract. Half of the chicks were injected subcutaneously with dexamethasone for 4 days before the infective challenge. At days 0 and 7, the effects of chicken lineage and immunosuppressive treatment on pulmonary fungal burden were analyzed using two linear mixed models. The pathogenicity of A. fumigatus varied according to the lineage: no clinical signs and no mortality were observed in layer chickens whereas more than 50% of mortality occurred in broilers. The effect of immunosuppressive treatment was also demonstrated, notably on animals weight but also on mortality.

European surveillance for pantropic canine coronavirus.

Highly virulent pantropic canine coronavirus (CCoV) strains belonging to subtype IIa were recently identified in dogs. To assess the distribution of such strains in Europe, tissue samples were collected from 354 dogs that had died after displaying systemic disease in France (n = 92), Hungary (n = 75), Italy (n = 69), Greece (n = 87), The Netherlands (n = 27), Belgium (n = 4), and Bulgaria (n = 1). A total of 124 animals tested positive for CCoV, with 33 of them displaying the virus in extraintestinal tissues. Twenty-four CCoV strains (19.35% of the CCoV-positive dogs) detected in internal organs were characterized as subtype IIa and consequently assumed to be pantropic CCoVs. Sequence and phylogenetic analyses of the 5' end of the spike protein gene showed that pantropic CCoV strains are closely related to each other, with the exception of two divergent French viruses that clustered with enteric strains.

IS-98-ST1 West Nile virus derived from an infectious cDNA clone retains neuroinvasiveness and neurovirulence properties of the original virus.

Infectious clones of West Nile virus (WNV) have previously been generated and used to decipher the role of viral proteins in WNV virulence. The majority of molecular clones obtained to date have been derived from North American, Australian, or African isolates. Here, we describe the construction of an infectious cDNA clone of a Mediterranean WNV strain, IS-98-ST1. We characterized the biological properties of the recovered recombinant virus in cell culture and in mice. The growth kinetics of recombinant and parental WNV were similar in Vero cells. Moreover, the phenotype of recombinant and parental WNV was indistinguishable as regards viremia, viral load in the brain, and mortality in susceptible and resistant mice. Finally, the pathobiology of the infectious clone was examined in embryonated chicken eggs. The capacity of different WNV strains to replicate in embryonated chicken eggs closely paralleled their ability to replicate in mice, suggesting that inoculation of embryonated chicken eggs could provide a practical in vivo model for the study of WNV pathogenesis. In conclusion, the IS-98-ST1 infectious clone will allow assessment of the impact of selected mutations and novel genomic changes appearing in emerging European strains pathogenicity and endemic or epidemic potential. This will be invaluable in the context of an increasing number of outbreaks and enhanced severity of infections in the Mediterranean basin and Eastern Europe.

Parotid salivary duct sialocele associated with glandular duct stenosis in a cat.

Feline parotid salivary duct sialocele is an uncommon disorder that has been previously reported in association with traumatic rupture of the duct in only two cats. Both cases were successfully treated by proximal duct ligation. We describe the successful surgical treatment of a parotid duct sialocele, secondary to spontaneous salivary duct stenosis, in an adult domestic shorthair cat. The cat was referred for assessment of a recurrent fluid-filled swelling on the left side of the face. Cytology of the aspirated fluid was consistent with serous saliva. The anatomical localisation of the lesion and the nature of the fluid were indicative of parotid gland/duct involvement. Retrograde sialography by parotid duct cannulation was unsuccessful because the left parotid duct opening was stenosed and obstructed by scar tissue. Surgical exploration revealed a parotid salivary duct sialocele, which was completely removed along with the parotid gland without complications.

[Usual values in veterinary haematology]. / Les valeurs usuelles en hématologie vétérinaire.

The goal of this article is to present the technical aspects and the applications of the blood cells examination and haemostasis in dogs and cats. Technical realisation of blood counts, cytology of normal and abnormal blood cells and significance of the pathologic cell counts are successively treated. Distinctive features of cytology and cell counts in herbivores, horses and cattle, are detailed in a separate chapter.Difficulties of veterinary haematology lie in qualitative and quantitative differences between blood cells of various animal species.Bone marrow cells exploration is not performed in this review.