RESUMEN
Effective vaccines are essential for the control of the coronavirus disease 2019 (COVID-19) pandemic. Currently developed vaccines inducing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S)-antigen-specific neutralizing antibodies (NAbs) are effective, but the appearance of NAb-resistant S variant viruses is of great concern. A vaccine inducing S-independent or NAb-independent SARS-CoV-2 control may contribute to containment of these variants. Here, we investigate the efficacy of an intranasal vaccine expressing viral non-S antigens against intranasal SARS-CoV-2 challenge in cynomolgus macaques. Seven vaccinated macaques exhibit significantly reduced viral load in nasopharyngeal swabs on day 2 post-challenge compared with nine unvaccinated controls. The viral control in the absence of SARS-CoV-2-specific NAbs is significantly correlated with vaccine-induced, viral-antigen-specific CD8+ T cell responses. Our results indicate that CD8+ T cell induction by intranasal vaccination can result in NAb-independent control of SARS-CoV-2 infection, highlighting a potential of vaccine-induced CD8+ T cell responses to contribute to COVID-19 containment.
Asunto(s)
Administración Intranasal/métodos , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Linfocitos T CD8-positivos/inmunología , Vacunas contra la COVID-19/administración & dosificación , COVID-19/inmunología , COVID-19/prevención & control , SARS-CoV-2/inmunología , Vacunación/métodos , Animales , COVID-19/epidemiología , COVID-19/virología , Vacunas contra la COVID-19/inmunología , Chlorocebus aethiops , Proteínas de la Envoltura de Coronavirus/inmunología , Proteínas M de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/inmunología , Modelos Animales de Enfermedad , Femenino , Macaca fascicularis , Masculino , Pandemias/prevención & control , Fosfoproteínas/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Resultado del Tratamiento , Células Vero , Carga ViralRESUMEN
One safety concern during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine development has been the vaccine-associated enhanced disease, which is characterized by eosinophilic immunopathology and T helper cell type 2 (TH2)biased immune responses with insufficient neutralizing antibodies. In this study, we established a lethal animal model using BALB/c mice and a mouse-passaged isolate (QHmusX) from a European lineage of SARS-CoV-2. The QHmusX strain induced acute respiratory illness, associated with diffuse alveolar damage and pulmonary edema, in TH2-prone adult BALB/c mice, but not in young mice or TH1-prone C57BL/6 mice. We also showed that immunization of adult BALB/c mice with recombinant spike protein without appropriate adjuvant caused eosinophilic immunopathology with TH2-shifted immune response and insufficient neutralizing antibodies after QHmusX infection. This lethal mouse model is useful for evaluating vaccine-associated enhanced respiratory disease during SARS-CoV-2 infection and may provide new insights into the disease pathogenesis of SARS-CoV-2.
RESUMEN
Potent neutralizing SARS-CoV-2 antibodies often target the spike protein receptor-binding site (RBS), but the variability of RBS epitopes hampers broad neutralization of multiple sarbecoviruses and drifted viruses. Here, using humanized mice, we identified an RBS antibody with a germline VH gene that potently neutralized SARS-related coronaviruses, including SARS-CoV and SARS-CoV-2 variants. X-ray crystallography revealed coordinated recognition by the heavy chain of non-RBS conserved sites and the light chain of RBS with a binding angle mimicking the angiotensin-converting enzyme 2 (ACE2) receptor. The minimum footprints in the hypervariable region of RBS contributed to the breadth of neutralization, which was enhanced by immunoglobulin G3 (IgG3) class switching. The coordinated binding resulted in broad neutralization of SARS-CoV and emerging SARS-CoV-2 variants of concern. Low-dose therapeutic antibody treatment in hamsters reduced the virus titers and morbidity during SARS-CoV-2 challenge. The structural basis for broad neutralizing activity may inform the design of a broad spectrum of therapeutics and vaccines.
Asunto(s)
Anticuerpos ampliamente neutralizantes/inmunología , Reacciones Cruzadas/inmunología , SARS-CoV-2/inmunología , Animales , Betacoronavirus/inmunología , Sitios de Unión de Anticuerpos , Anticuerpos ampliamente neutralizantes/química , Anticuerpos ampliamente neutralizantes/uso terapéutico , COVID-19/prevención & control , COVID-19/terapia , COVID-19/virología , Cricetinae , Humanos , Cambio de Clase de Inmunoglobulina , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G/química , Inmunoglobulina G/inmunología , Ratones , Dominios Proteicos , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismoRESUMEN
The rabies virus is one of the most neurotropic of all viruses infecting mammals. During the terminal phases of infection, the virus spreads to peripheral tissues, including the skin. The external skin of the nose, called the nasal planum, is a sensory organ where numerous nerve bundles and terminal nerves are distributed. Therefore, the nasal planum is expected to serve as a postmortem diagnostic material. However, the distribution of rabies virus antigens in the nasal planum in rabid animals has not yet been studied. In this study, the nasal planum was obtained from 45 rabid dogs. In all rabid dogs, the viral antigen was detected in the peripheral nerve tissues, Merkel cells, and squamous cells. The viral antigen in the epidermis exhibited three patterns: first, a diffuse positive pattern from the basal layer to the squamous layer; second, a reticular positive pattern along the cell membrane in the squamous layer; and third, a basal layer pattern of the epidermis. In the dermis, viral antigens were detected more often in lamellated corpuscles just beneath the rete pegs. These results suggest that the nasal planum could serve as a useful alternative source for postmortem diagnosis in rabies endemic countries.
Asunto(s)
Antígenos Virales , Animales , Autopsia/veterinaria , PerrosRESUMEN
SARS-CoV-2 infection presents clinical manifestations ranging from asymptomatic to fatal respiratory failure. Despite the induction of functional SARS-CoV-2-specific CD8+ T-cell responses in convalescent individuals, the role of virus-specific CD8+ T-cell responses in the control of SARS-CoV-2 replication remains unknown. In the present study, we show that subacute SARS-CoV-2 replication can be controlled in the absence of CD8+ T cells in cynomolgus macaques. Eight macaques were intranasally inoculated with 105 or 106 TCID50 of SARS-CoV-2, and three of the eight macaques were treated with a monoclonal anti-CD8 antibody on days 5 and 7 post-infection. In these three macaques, CD8+ T cells were undetectable on day 7 and thereafter, while virus-specific CD8+ T-cell responses were induced in the remaining five untreated animals. Viral RNA was detected in nasopharyngeal swabs for 10-17 days post-infection in all macaques, and the kinetics of viral RNA levels in pharyngeal swabs and plasma neutralizing antibody titers were comparable between the anti-CD8 antibody treated and untreated animals. SARS-CoV-2 RNA was detected in the pharyngeal mucosa and/or retropharyngeal lymph node obtained at necropsy on day 21 in two of the untreated group but undetectable in all macaques treated with anti-CD8 antibody. CD8+ T-cell responses may contribute to viral control in SARS-CoV-2 infection, but our results indicate possible containment of subacute viral replication in the absence of CD8+ T cells, implying that CD8+ T-cell dysfunction may not solely lead to viral control failure.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , COVID-19/veterinaria , Macaca fascicularis/inmunología , Macaca fascicularis/virología , Enfermedades de los Monos/inmunología , Enfermedades de los Monos/virología , SARS-CoV-2/inmunología , SARS-CoV-2/fisiología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19/inmunología , COVID-19/virología , Modelos Animales de Enfermedad , Femenino , Humanos , Cinética , Depleción Linfocítica/veterinaria , Masculino , ARN Viral/genética , ARN Viral/metabolismo , SARS-CoV-2/genética , Replicación Viral/inmunologíaRESUMEN
We previously reported a novel diagnostic method using follicle-sinus complexes (FSCs) in the muzzle skin for postmortem diagnosis of rabies in dogs. However, whether this method works in other animal species remains unclear. Here, FSCs were collected from a wolf, a red fox, 2 bats, and a cat, and examined for the presence of viral antigen, viral mRNA, and viral particles. Viral antigen and viral mRNA were confirmed in Merkel cells (MCs) in FSCs of all species. Electron microscopy performed using only samples from wolf and cat confirmed viral particles in MCs of FSCs. These results suggested that this novel diagnostic method using FSCs might be useful for detection of rabies not only in domestic but also wild animals.
Asunto(s)
Folículo Piloso/virología , Células de Merkel/virología , Virus de la Rabia/aislamiento & purificación , Rabia/veterinaria , Piel/virología , Animales , Animales Salvajes/virología , Antígenos Virales/análisis , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/virología , Gatos , Quirópteros/virología , Zorros/virología , Folículo Piloso/inervación , Células de Merkel/ultraestructura , ARN Mensajero , Rabia/diagnóstico , Rabia/virología , Virus de la Rabia/inmunología , Virus de la Rabia/ultraestructura , Piel/inervación , Lobos/virologíaRESUMEN
In the present study, follicle-sinus complexes (FSCs) were harvested from the muzzle skin of 123 dogs with suspected canine rabies, and the sensitivity and specificity of FSC analysis were compared with those of brain tissue immunohistochemistry analysis. In the FSCs, viral antigen was detected from Merkel cells. Sensitivity was 97.3%, specificity was 100%, and the coefficient κ was 0.88. These results reconfirm that FSCs are very useful for the postmortem diagnosis of canine rabies, and suggest that 5 FSCs can yield results that are almost equivalent to those derived from brain tissue analysis in rabid dogs.
Asunto(s)
Enfermedades de los Perros/diagnóstico , Folículo Piloso/virología , Rabia/veterinaria , Animales , Antígenos Virales/inmunología , Diagnóstico , Enfermedades de los Perros/patología , Enfermedades de los Perros/virología , Perros , Femenino , Folículo Piloso/inervación , Folículo Piloso/patología , Hipocampo/patología , Hipocampo/virología , Masculino , Bulbo Raquídeo/patología , Bulbo Raquídeo/virología , Células de Merkel/virología , Rabia/diagnóstico , Rabia/patología , Virus de la Rabia/inmunología , Sensibilidad y Especificidad , Piel/inervaciónRESUMEN
Recently, we reported that follicle-sinus complexes (FSCs) in the muzzle skin are useful for postmortem diagnosis of rabid dogs. Here, we compared the sensitivity and specificity of detecting the viral antigen in the brain and FSCs of 226 suspected rabid dogs, and assessed whether the FSC harbored the virus genome and particles. The viral antigen was detected in 211 of 226 samples with 100% sensitivity and specificity. Viral RNA and particles were observed in the cytoplasm of Merkel cells (MCs). These results suggest that MCs are targets of virus infection and FSCs are useful material for diagnosing rabies.
Asunto(s)
Enfermedades de los Perros/diagnóstico , Rabia/veterinaria , Piel/patología , Animales , Antígenos Virales/análisis , Encéfalo/patología , Diagnóstico , Enfermedades de los Perros/patología , Perros , Femenino , Masculino , Rabia/diagnóstico , Rabia/patología , Sensibilidad y Especificidad , Piel/inervación , Piel/virologíaRESUMEN
We established a system for the recovery of a segmented recombinant rabies virus, the virus genome RNA of which was divided into two parts: segment 1 encoding the nucleoprotein, phosphoprotein, matrix protein, and glycoprotein genes, and segment 2 encoding the large RNA-dependent RNA polymerase gene. The morphology of the segmented recombinant rabies virus was bullet-like in shape with a length of approximately 130â¯nm, which is shorter than the 200-nm long non-segmented recombinant rabies virus. The segmented recombinant rabies virus was maintained for at least 18 passages. The virus multiplication rate of the segmented recombinant rabies virus was lower than that of the non-segmented recombinant rabies virus during the passages, and the relative amounts of virus genome RNAs for segment 1 and segment 2 differed in the supernatant of the segmented recombinant rabies virus infected cells. These results suggest that the segmented recombinant rabies virus packages either segment 1 or segment 2 into each virus particle. Thus, co-infection with segmented recombinant rabies virus particles packaging segment 1 or segment 2 may be necessary for the production of progeny virus.
Asunto(s)
Genoma Viral , ARN Viral/genética , Virus de la Rabia/genética , Línea Celular , Glicoproteínas/genética , Nucleoproteínas/genética , Fosfoproteínas/genética , ARN Polimerasa Dependiente del ARN/genética , Virus de la Rabia/enzimología , Virión/genética , Replicación ViralRESUMEN
This case report describes a congenital ganglioneuroblastoma in a 38-day-old male Japanese Black calf. The cervical multinodular mass was present at birth and grew rapidly. The cut surface was pale gray-to-yellow and had a gelatinous appearance. Hemorrhagic cysts of various sizes were observed in the nodule. Histologically, the mass contained clusters of neuroblastic cells, ganglionic cells, and Schwann-like cells. Immunohistochemically, the ganglionic cells showed strong positivity for neuron-specific enolase, neurofilament, synaptophysin, and chromogranin A, whereas the Schwann-like cells strongly expressed S-100, glial fibrillary acidic protein, and vimentin. Ultrastructurally, neurosecretory granules resembling catecholamine were observed in the neuroblastic and Schwann-like cells. Based on the pathology, the diagnosis was congenital cervical nodular ganglioneuroblastoma.
Asunto(s)
Enfermedades de los Bovinos/congénito , Ganglioneuroblastoma/veterinaria , Neoplasias de Cabeza y Cuello/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/patología , Vértebras Cervicales , Ganglioneuroblastoma/congénito , Ganglioneuroblastoma/ultraestructura , Neoplasias de Cabeza y Cuello/congénito , Neoplasias de Cabeza y Cuello/ultraestructura , MasculinoRESUMEN
During rabies virus infections, the minor salivary glands are one of the important organs for virus replication and excretion into the oral cavity. However, details of pathological findings and viral antigen distribution in the minor salivary glands remain poorly understood. In this study, we conducted pathological tests on the tongues of 71 rabid dogs in the Philippines; the minor salivary glands (von Ebner's glands, lingual glands), circumvallate papilla, autonomic ganglia, and skeletal muscles were evaluated. Inflammatory changes were observed in the von Ebner's glands of 20/71 dogs, in the circumvallate papilla of 10/71, and in the tongue muscle of 1/71. Conversely, no morphological changes were observed in the lingual glands and autonomic ganglia. Viral antigens were detected via immunohistochemistry-based methods in the cytoplasm of the acinar epithelium in the von Ebner's glands of all 71 dogs. Virus particles were confirmed in the intercellular canaliculi and acinar lumen via electron microscopy. In the autonomic ganglia, viral antigens were detected in 67/71 rabid dogs. Viral antigens were detected in the taste buds of all 71 dogs, and were distributed mainly in type II and III taste bud cells. In tongue muscle fibers, viral antigens were detected in 11/71 dogs. No virus antigens were detected in lingual glands. These findings suggest that rabies virus descends in the tongue along the glossopharyngeal nerve after proliferation in the brain, and von Ebner's glands and taste buds are one of the portals of virus excretion into the saliva in rabid dogs.
Asunto(s)
Ganglios Autónomos/patología , Virus de la Rabia/patogenicidad , Glándulas Salivales Menores/patología , Papilas Gustativas/patología , Lengua/patología , Virión/patogenicidad , Animales , Antígenos Virales/genética , Antígenos Virales/inmunología , Perros , Femenino , Ganglios Autónomos/ultraestructura , Ganglios Autónomos/virología , Inmunohistoquímica , Masculino , Músculo Esquelético/patología , Músculo Esquelético/ultraestructura , Músculo Esquelético/virología , Filipinas , Rabia/patología , Rabia/virología , Virus de la Rabia/fisiología , Virus de la Rabia/ultraestructura , Saliva/virología , Glándulas Salivales Menores/ultraestructura , Glándulas Salivales Menores/virología , Papilas Gustativas/ultraestructura , Papilas Gustativas/virología , Lengua/ultraestructura , Lengua/virología , Virión/fisiología , Virión/ultraestructura , Esparcimiento de Virus/fisiologíaRESUMEN
Most studies on rabies virus pathogenesis in animal models have employed fixed rabies viruses, and the results of those employing street rabies viruses have been inconsistent. Therefore, to clarify the pathogenesis of street rabies virus (1088 strain) in mice, 106 focus forming units were inoculated into the right hindlimb of ddY mice (6 weeks, female). At 3 days postinoculation (DPI), mild inflammation was observed in the hindlimb muscle. At 5 DPI, ganglion cells in the right lumbosacral spinal dorsal root ganglia showed chromatolysis. Axonal degeneration and inflammatory cells increased with infection progress in the spinal dorsal horn and dorsal root ganglia. Right hindlimb paralysis was observed from 7 DPI, which progressed to quadriparalysis. However, no pathological changes were observed in the ventral horn and root fibers of the spinal cord. Viral antigen was first detected in the right hindlimb muscle at 3 DPI, followed by the right lumbosacral dorsal root ganglia, dorsal horn of spinal cord, left red nuclei, medulla oblongata and cerebral cortex (M1 area) at 5 DPI. These results suggested that the 1088 virus ascended the lumbosacral spinal cord via mainly afferent fibers at early stage of infection and moved to cerebral cortex (M1 area) using descending spinal tract. Additionally, we concluded that significant pathological changes in mice infected with 1088 strain occur in the sensory tract of the spinal cord; this selective susceptibility results in clinical features of the disease.
Asunto(s)
Sistema Nervioso Central/patología , Rabia/patología , Animales , Antígenos Virales/análisis , Femenino , Ganglios Espinales/patología , Ganglios Espinales/virología , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Inflamación , Ratones , Rabia/virología , Virus de la Rabia/patogenicidad , Virus de la Rabia/ultraestructuraRESUMEN
The direct fluorescent antibody test (dFAT) on fresh brain tissues is the gold standard for rabies virus antigen detection in dogs. However, this method is laborious and holds a high risk of virus exposure for the experimenter. Skin biopsies are useful for the diagnosis of humans and animals. In mammals, the tactile hair, known as the follicle-sinus complex (FSC), is a specialized touch organ that is abundant in the muzzle skin. Each tactile hair is equipped with more than 2,000 sensory nerve endings. Therefore, this organ is expected to serve as an alternative postmortem diagnostic material. However, the target cells and localization of rabies virus antigen in the FSCs remain to be defined. In the present study, muzzle skins were obtained from 60 rabid dogs diagnosed with rabies by dFAT at the Research Institute of Tropical Medicine in the Philippines. In all dogs, virus antigen was clearly detected in a part of the outer root sheath at the level of the ring sinus of the FSCs, and the majority of cells were positive for the Merkel cell (MC) markers cytokeratin 20 and CAM5.2. Our results suggest that MCs in the FSCs of the muzzle skin are a target for virus replication and could serve as a useful alternative specimen source for diagnosis of rabies.
Asunto(s)
Antígenos Virales/aislamiento & purificación , Enfermedades de los Perros/diagnóstico , Folículo Piloso/virología , Inmunohistoquímica/métodos , Células de Merkel/virología , Virus de la Rabia/aislamiento & purificación , Rabia/veterinaria , Piel/virología , Animales , Antígenos Virales/inmunología , Antígenos Virales/ultraestructura , Diagnóstico , Técnicas y Procedimientos Diagnósticos , Enfermedades de los Perros/virología , Perros , Folículo Piloso/ultraestructura , Células de Merkel/ultraestructura , Rabia/diagnóstico , Rabia/virología , Virus de la Rabia/inmunología , Virus de la Rabia/ultraestructura , Piel/patología , Coloración y EtiquetadoRESUMEN
An 11-year-old castrated male rabbit presented with a subcutaneous mass in the right hind limb. The mass comprised solid and myxoid areas. Solid areas were characterized by a storiform or interlacing pattern of spindle cells, strap cells, multinucleated giant cells and round cells with eccentrically located nuclei, whereas the myxoid areas were composed predominantly of elongated fusiform cells with hyperchromatic nuclei embedded in Alcian Blue-positive myxoid stroma. Immunohistochemically, tumor cells in both areas were positive for desmin and vimentin. Ultrastructurally, the tumor cells in the solid areas had abundant myofilaments with electron dense Z-band structures. Based on these pathological findings, this case was diagnosed as rhabdomyosarcoma in a rabbit.
Asunto(s)
Neoplasias de los Músculos/veterinaria , Conejos/anatomía & histología , Rabdomiosarcoma/veterinaria , Animales , Masculino , Neoplasias de los Músculos/diagnóstico , Neoplasias de los Músculos/patología , Músculo Esquelético/patología , Rabdomiosarcoma/diagnóstico , Rabdomiosarcoma/patologíaRESUMEN
A two-year-old castrated male Pomeranian dog was referred with the chief complaints of coughing and subcutaneous emphysema. On physical examination, the crepitant areas were palpable. When auscultated, the right chest was absent of respiratory sound, while the sound of the opposite side was enhanced. Radiographs presented pneumothorax and pneumomediastinum. On computed tomography, hypoattenuated bulla-like lesion at right middle lung lobe and trapped air in mediastinum were shown. After patient stabilization, surgery for excision of affected lobe was performed. During follow-up period, there were no recurrence and complication on radiographic examination. Based on clinical and pathological findings, the dog was diagnosed as congenital lobar emphysema.
Asunto(s)
Enfermedades de los Perros/congénito , Enfisema/veterinaria , Enfisema Mediastínico/veterinaria , Neumotórax/veterinaria , Animales , Enfermedades de los Perros/diagnóstico por imagen , Enfermedades de los Perros/patología , Perros , Enfisema/complicaciones , Enfisema/congénito , Enfisema/patología , Masculino , Enfisema Mediastínico/complicaciones , Enfisema Mediastínico/diagnóstico por imagen , Enfisema Mediastínico/patología , Neumotórax/complicaciones , Neumotórax/diagnóstico por imagen , Neumotórax/patología , Radiografía/veterinaria , Tomografía Computarizada por Rayos X/veterinariaRESUMEN
Rabies is a zoonotic disease caused by the rabies virus. While the salivary glands are important as exit and propagation sites for the rabies virus, the mechanisms of rabies excretion remain unclear. Here, we investigated the histopathology of the salivary glands of rabid dogs and analyzed the mechanism of excretion into the oral cavity. Mandibular and parotid glands of 22 rabid dogs and three control dogs were used. Mild to moderate non-suppurative sialadenitis was observed in the mandibular glands of 19 of the 22 dogs, characterized by loss of acinar epithelium and infiltration by lymphoplasmacytic cells. Viral antigens were detected in the mucous acinar epithelium, ganglion neurons and myoepithelium. Acinar epithelium and lymphocytes were positive for anti-caspase-3 antibodies and TUNEL staining. In contrast, no notable findings were observed in the ductal epithelial cells and serous demilune. In the parotid gland, the acinar cells, myoepithelium and ductal epithelium all tested negative. These findings confirmed the path through which the rabies virus descends along the facial nerve after proliferation in the brain to reach the ganglion neurons of the mandibular gland, subsequently traveling to the acinar epithelium via the salivary gland myoepithelium. Furthermore, the observation that nerve endings passing through the myoepithelium were absent from the ductal system suggested that viral proliferation and cytotoxicity could not occur there, ensuring that secretions containing the virus are efficiently excreted into the oral cavity.
Asunto(s)
Enfermedades de los Perros/patología , Rabia/veterinaria , Glándulas Salivales/patología , Animales , Estudios de Casos y Controles , Enfermedades de los Perros/virología , Perros/virología , Femenino , Masculino , Filipinas , Rabia/patología , Glándulas Salivales/virologíaRESUMEN
A 15-year-old, female mixed-breed dog presented with abdominal distention. An exploratory laparotomy revealed a large left ovarian mass (20 × 15 × 12 cm). Histopathological examination of the mass revealed a mixed myxoid liposarcoma and a well-differentiated leiomyoma. Four months after surgical removal of the mass, the dog died due to multiorgan metastasis. The metastasis was composed solely of the liposarcoma component. The liposarcoma component was Alcian Blue- and Oil red O-positive, and demonstrated immunoreactivity with S-100, adipophilin and vimentin. Electron microscopy revealed that the tumor cell cytoplasms were packed with lipid vacuoles and dilated rough endoplasmic reticulum. To our knowledge, this is the first report of myxoid liposarcoma and leiomyoma co-existing in a canine ovary.