Project description:Purpose:MicroRNAs (miRNAs) are members of a rapidly growing class of small endogenous non-coding RNAs that play crucial roles in post-transcriptional regulator of gene expression in many biological processes. Feline Panleukopenia Virus (FPV) is a highly infectious pathogen that causes severe disease in pets, economically important animals and wildlife in worldwide. However, the molecular mechanisms underlying the pathogenicity of FPV have not been completely clear. To study the involvement of miRNAs in the FPV infection process, miRNAs expression profiles were identified via deep sequencing in the feline kidney cell line (F81) infected and uninfected with FPV. Methods:miRNA-sequencing analysis was performed on an Illumina Hiseq 2500 (LC Sciences, USA) following the vendor's recommended protocol Results:As a result, 673 known miRNAs belonging to 210 families and 278 novel miRNAs were identified. Then we found 57 significantly differential expression miRNAs by comparing the results between uninfected and FPV-infected groups. Furthermore, stem-loop qRT-PCR was applied to validate and profile the expression of the randomly selected miRNAs; the results were consistent with those by deep sequencing. Furthermore, the potential target genes were predicted. The target genes of differential expression miRNAs were analyzed by GO and KEGG pathway. Conclusions:The identification of miRNAs in feline kidney cell line before and after infection with Feline Panleukopenia Virus will provide new information and enhance our understanding of the functions of miRNAs in regulating biological processes.
Project description:Approximately 5% of cats in animal shelters in the United States test positive for either feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV), which translates to more than 100,000 positive cats managed by shelters each year. Little is known about the current status of retroviral management in animal shelters, particularly in regions burdened by chronic pet overpopulation and high shelter admissions, such as the southern United States. The purpose of this study was to describe feline retroviral management in Florida shelters. Shelters were surveyed on practices including selection of cats for testing, diagnostic techniques, and outcome options for cats with positive test results. Responses were received from 139 of 153 animal shelters known to admit cats, including 55 municipal shelters (40%), 70 private shelters (50%), and 14 private shelters with municipal contracts (10%). A total of 115 shelters (83%) performed at least some testing, most using combination point-of-care devices for simultaneous FeLV antigen and FIV antibody screening. Of shelters that performed any testing, 56 (49%) tested all cats for FeLV and 52 (45%) tested all cats for both FeLV and FIV. The most common reason for testing was screening adoptable cats (108 shelters; 94%) and cats available for transfer to other organizations (78; 68%). Testing cats in trap-neuter-return/return-to-field programs was least common (21; 18%). Most common outcome options for positive cats included adoption (74; 64%), transfer (62; 54%), and euthanasia (49; 43%). Euthanasia following a positive test result was more common for cats with FeLV (49; 43%) than for cats with FIV (29; 25%) and was more common in municipal shelters, rural shelters, shelters taking in <500 cats a year, and shelters with overall live outcome rates for cats <70%. Although Florida shelter compliance with national guidelines for identification and management of FeLV and FIV positive cats was variable, most had live outcome options for at least some of their cats with positive test results. Increased access to training and practical programmatic tools may help more shelters implement cost-effective testing protocols, reduce risk for transmission to other cats, and support the best outcomes for this vulnerable population of cats.
Project description:<p>Tick-borne encephalitis virus is an enveloped, pathogenic, RNA virus in the family Flaviviridae, genus Flavivirus. Viral particles are formed when the nucleocapsid, consisting of an RNA genome and multiple copies of the capsid protein, buds through the endoplasmic reticulum membrane and acquires the viral envelope and the associated proteins. The coordination of the nucleocapsid components to the sites of assembly and budding are poorly understood. Here, we investigate nucleocapsid assembly by characterizing the interactions of the wild-type and truncated capsid proteins with membranes by using biophysical methods and model membrane systems. We show that capsid protein initially binds membranes via electrostatic interactions with negatively-charged lipids which is followed by membrane insertion. Additionally, we show that membrane-bound capsid protein can recruit viral genomic RNA. We confirm the biological relevance of the biophysical findings by using mass spectrometry to show that purified virions contain negatively-charged lipids. Our results suggest that nucleocapsid assembly is coordinated by negatively-charged membrane patches on the endoplasmic reticulum and that the capsid protein mediates direct contacts between the nucleocapsid and the membrane.</p>
Project description:Feline leukemia virus (FeLV) is a retrovirus with variable rates of infection globally. DNA was obtained from cats' peripheral blood mononuclear cells, and proviral DNA of pol and env genes was detected using PCR. Seventy-six percent of cats scored positive for FeLV using env-PCR; and 54 %, by pol-PCR. Phylogenetic analysis of both regions identified sequences that correspond to a group that includes endogenous retroviruses. They form an independent branch and, therefore, a new group of endogenous viruses. Cat gender, age, outdoor access, and cohabitation with other cats were found to be significant risk factors associated with the disease. This strongly suggests that these FeLV genotypes are widely distributed in the studied feline population in Mexico.
Project description:From 2002 through 2005, an outbreak of feline leukemia virus (FeLV) occurred in Florida panthers (Puma concolor coryi). Clinical signs included lymphadenopathy, anemia, septicemia, and weight loss; 5 panthers died. Not associated with FeLV outcome were the genetic heritage of the panthers (pure Florida vs. Texas/Florida crosses) and co-infection with feline immunodeficiency virus. Genetic analysis of panther FeLV, designated FeLV-Pco, determined that the outbreak likely came from 1 cross-species transmission from a domestic cat. The FeLV-Pco virus was closely related to the domestic cat exogenous FeLV-A subgroup in lacking recombinant segments derived from endogenous FeLV. FeLV-Pco sequences were most similar to the well-characterized FeLV-945 strain, which is highly virulent and strongly pathogenic in domestic cats because of unique long terminal repeat and envelope sequences. These unique features may also account for the severity of the outbreak after cross-species transmission to the panther.
Project description:Infections with feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) occur worldwide and are among the most important infectious diseases in cats. The aim of the present study was to determine the prevalence of FIV and FeLV infection in healthy outdoor cats in North, Northeast and Central Thailand. So far, a study on retrovirus prevalence of healthy cats in Thailand in a larger geographic area has not been published yet. In addition, risk factors for FIV and FeLV infections were evaluated. Two hundred sixty healthy cats were prospectively recruited. They originated from 13 locations in North, Northeast, and Central Thailand and were presented for either preventive health care and/or neutering. In each cat, a physical examination was performed to confirm health status. FIV and FeLV status was determined using a commercial rapid enzyme-linked immunosorbent assay (ELISA) (SNAP Combo Plus FeLV/FIV, IDEXX). Risk factors were analyzed by binary logistic regression analysis. Samples of 15/260 (5.8%) cats were positive for FIV antibodies, and 11/260 (4.2%) samples were positive for FeLV antigen. One of the 260 (0.4%) cats was positive for both, FIV and FeLV infection. In binary logistic regression analysis, no parameter was associated with a higher risk for FeLV infection. However, cats had a significantly (p = 0.025) higher risk for FIV infection when they were 2 years or older. FIV and FeLV infections occur in healthy cats in North, Northeast and Central Thailand, but prevalence was lower than expected. No risk factors for FeLV infection were detected, but risk for FIV infection increases with age.
Project description:Feline foamy virus (FFV) and feline leukemia virus (FeLV) belong to the Retroviridae family. While disease has not been reported for FFV infection, FeLV infection can cause anemia and immunosuppression (progressive infection). Co-infection with FFV/FeLV allows evaluation of the pathogenic potential and epidemiology of FFV infection in cats with FeLV pathology. Blood and buccal swab samples from 81 cats were collected in Rio de Janeiro. Plasma was serologically tested for FeLV. DNA extracted from peripheral blood mononuclear cells and buccal swabs was used to PCR detect FFV and FeLV. A qPCR was developed to detect and measure FFV proviral loads (pVLs) in cats. FeLV qPCR was performed using previous methods. The median log10 pVL of FFV mono-infected individuals was lower than found in FFV/FeLV co-infected cats in buccal swabs (p = 0.003). We found 78% of cats had detectable buccal FFV DNA in FFV mono-infected and FFV co-infected FeLV-progressive cats, while in FeLV-regressive cats (those without signs of disease) 22% of cats had detectable buccal FFV DNA (p = 0.004). Our results suggest that regressive FeLV infection may reduce FFV saliva transmission, the main mode of FV transmission. We did not find evidence of differences in pathogenicity in FFV mono- and -dually infected cats. In summary, we show that FVs may interact with FeLV within the same host. Our study supports the utility of cats naturally co-infected with retroviruses as a model to investigate the impact of FV on immunocompromised mammalian hosts.