RESUMO
Diseases such as those caused by feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) represent health problems for cats. Feline leishmaniasis (FL) has been reported in several cities across the country. The objective was to carry out a clinical-epidemiological and laboratory study of FIV, FeLV and FL in cats from shelters in Dourados, Mato Grosso do Sul, Brazil. Blood samples and swabs from the conjunctival and nasal mucosa were obtained from 75 cats, from four animal shelters. Serology for FIV and FeLV was performed. For Leishmania, polymerase chain reaction (PCR) was performed on blood, conjunctiva and nasal mucosa. In the immunochromatographic serological test, seven cats tested positive for FIV and none for FeLV. No samples was positive in PCR for Leishmania. The study showed that despite the presence of human and canine leishmaniasis in the studied region, Leishmania spp. were absent in the cats studied. To avoid an increase in contagion in shelters, it is essential isolate cats with FIV.
Assuntos
Doenças do Gato , Vírus da Imunodeficiência Felina , Leishmaniose , Vírus da Leucemia Felina , Animais , Gatos , Brasil/epidemiologia , Vírus da Imunodeficiência Felina/isolamento & purificação , Vírus da Leucemia Felina/isolamento & purificação , Vírus da Leucemia Felina/genética , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Doenças do Gato/virologia , Prevalência , Masculino , Leishmaniose/veterinária , Leishmaniose/epidemiologia , Feminino , Leishmania/isolamento & purificaçãoRESUMO
Infection and clinical cases of leishmaniasis caused by Leishmania infantum in cats have been increasingly reported in several countries, including Brazil. In this study, we used an enzyme-linked immunosorbent assay (ELISA) and an immunochromatographic test (ICT) based on a recombinant antigen (rKDDR-plus) to detect anti-Leishmania antibodies in cats from an animal shelter in northeastern Brazil. We compared the results with an ELISA using L. infantum crude antigen (ELISA-CA). We also investigated the presence of Leishmania DNA in blood or ocular conjunctival samples as well as the association between Leishmania PCR positivity and serological positivity to feline immunodeficiency virus (FIV), feline leukemia virus (FeLV) and Toxoplasma gondii. Concerning serological assays, a higher positivity was detected using the ICT-rKDDR-plus (7.5%; 7/93) as compared to ELISA-rKDDR-plus (5.4%; 5/93) and ELISA-CA (4.3%; 4/93). Upon PCR testing, 52.7% (49/93) of the ocular conjunctival swabs and 48.3% (44/91) of the blood samples were positive. Together, PCR and serological testing revealed overall positivities of 73.1% (68/93) and 12.9% (12/93), respectively. Among PCR-positive samples, 45.5% (31/68) showed co-infection with FIV, 17.6% (12/68) with FeLV, and 82.3% (56/68) with T. gondii. More than half of the PCR-positive cats showed at least one clinical sign suggestive of leishmaniasis (58.8%; 40/68) and dermatological signs were the most frequent ones (45.5%; 31/68). Both tests employing the recombinant antigen rKDDR-plus (i.e., ICT-rKDDR-plus and ELISA-rKDDR-plus) detected more positive cats than the ELISA-CA but presented low overall accuracy. PCR testing using either blood or ocular conjunctival samples detected much more positive cats than serological tests.
Assuntos
Doenças do Gato , Coinfecção , Ensaio de Imunoadsorção Enzimática , Vírus da Imunodeficiência Felina , Leishmania infantum , Vírus da Leucemia Felina , Proteínas Recombinantes , Gatos , Animais , Doenças do Gato/diagnóstico , Doenças do Gato/parasitologia , Doenças do Gato/virologia , Doenças do Gato/sangue , Doenças do Gato/epidemiologia , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Vírus da Imunodeficiência Felina/isolamento & purificação , Coinfecção/veterinária , Coinfecção/parasitologia , Coinfecção/epidemiologia , Coinfecção/virologia , Leishmania infantum/isolamento & purificação , Vírus da Leucemia Felina/genética , Vírus da Leucemia Felina/imunologia , Masculino , Feminino , Toxoplasma , Anticorpos Antiprotozoários/sangue , Leishmaniose Visceral/veterinária , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/sangue , Reação em Cadeia da Polimerase/veterinária , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/sangueRESUMO
The feline leukemia virus (FeLV) belongs to the Retroviridae family and Gammaretrovirus genus, and causes a variety of neoplastic and non-neoplastic diseases in domestic cats (Felis catus), such as thymic and multicentric lymphomas, myelodysplastic syndromes, acute myeloid leukemia, aplastic anemia, and immunodeficiency. The aim of the present study was to carry out the molecular characterization of FeLV-positive samples and determine the circulating viral subtype in the city of São Luís, Maranhão, Brazil, as well as identify its phylogenetic relationship and genetic diversity. The FIV Ac/FeLV Ag Test Kit (Alere™) and the commercial immunoenzymatic assay kit (Alere™) were used to detect the positive samples, which were subsequently confirmed by ELISA (ELISA - SNAP® Combo FeLV/FIV). To confirm the presence of proviral DNA, a polymerase chain reaction (PCR) was performed to amplify the target fragments of 450, 235, and 166 bp of the FeLV gag gene. For the detection of FeLV subtypes, nested PCR was performed for FeLV-A, B, and C, with amplification of 2350-, 1072-, 866-, and 1755-bp fragments for the FeLV env gene. The results obtained by nested PCR showed that the four positive samples amplified the A and B subtypes. The C subtype was not amplified. There was an AB combination but no ABC combination. Phylogenetic analysis revealed similarities (78% bootstrap) between the subtype circulating in Brazil and FeLV-AB and with the subtypes of Eastern Asia (Japan) and Southeast Asia (Malaysia), demonstrating that this subtype possesses high genetic variability and a differentiated genotype.
Assuntos
Doenças do Gato , Vírus da Imunodeficiência Felina , Gatos , Animais , Vírus da Leucemia Felina/genética , Brasil , Filogenia , Genótipo , Reação em Cadeia da Polimerase/veterinária , Vírus da Imunodeficiência Felina/genéticaRESUMO
To date, only a few studies have examined the impacts of feline leukemia virus (FeLV) subgroups on disease development in spontaneously infected cats. The present study identified FeLV-A and FeLV-B subgroups in cats with lymphoma and leukemia and explored the phylogenetic relationships of env sequences. Twenty-six cats with lymphoma (n=16) or leukemia (n=10) were selected. FeLV p27 antigen positivity was determined using ELISA, and proviral DNA in blood samples was detected using nested PCR. Positive animals in both tests were classified as cases of FeLV progressive infection and subjected to a second nested PCR for env amplification and subgroup determination. Six samples of FeLV-A and five samples of FeLV-B were sequenced using the Sanger method, and the results were used to build a phylogenetic tree and estimate evolutionary divergence. Among cats with lymphoma, 68.8% carried FeLV-AB and 31.2% FeLV-A. Among cats with leukemia, 70% carried FeLV-AB and 30% FeLV-A. Regarding cat characteristics, 50% were young, 30.8% young adults, and 19.2% adults; 88.5% were mixed-breed and 11.5% pure breed; and 42.3% were males and 57.7% were females. Among lymphomas, 62.5% were mediastinal, 31.3% multicentric, and 6.3% extranodal. Regarding histological classification, lymphoblastic and small non-cleaved-cell lymphomas were the most frequently detected. Among leukemia cases, 30% were acute lymphoid, 30% chronic myeloid, and 40% acute myeloid. Phylogenetic analysis showed that FeLV-A SC sequences were closely related to the Arena, Glasgow-1, and FeLV-FAIDS variants. Meanwhile, FeLV-B SC sequences were divergent from one another but similar to the endogenous FELV env gene (enFeLV). In conclusion, FeLV-AB is prevalent in cats with lymphoma and leukemia, highlighting the genetic diversity involved in the pathogenesis of these neoplasms in Brazil.
Assuntos
Leucemia Felina , Linfoma , Masculino , Feminino , Gatos , Animais , Vírus da Leucemia Felina/genética , Filogenia , Provírus/genética , Linfoma/veterináriaRESUMO
Feline leukaemia virus (FeLV) is a retrovirus that infects domestic and wild cats around the world. FeLV infection is associated with the development of neoplasms, bone marrow disorders and immunosuppression. Viral subgroups arise from mutations in the FeLV genome or from recombination of FeLV with ancestral endogenous retroviruses in the cat genome. The retroviral endogenisation process has allowed generation of a diversity of endogenous viruses, both functional and defective. These elements may be part of the normal functioning of the feline genome and may also interact with FeLV to form recombinant FeLV subgroups, enhance pathogenicity of viral subgroups, or inhibit and/or regulate other retroviral infections. Recombination of the env gene occurs most frequently and appears to be the most significant in terms of both the quantity and diversification of pathogenic effects in the viral population, as well as affecting cell tropism and types of disease that occur in infected cats. This review focuses on available information regarding genetic diversity, pathogenesis and diagnosis of FeLV as a result of the interaction between endogenous and exogenous viruses.
Assuntos
Doenças do Gato , Retrovirus Endógenos , Leucemia Felina , Infecções por Retroviridae , Gatos , Animais , Vírus da Leucemia Felina/genética , Vírus da Leucemia Felina/metabolismo , Retrovirus Endógenos/genética , Leucemia Felina/genética , Genes env , Infecções por Retroviridae/veterinária , Infecções por Retroviridae/genética , Doenças do Gato/genéticaRESUMO
Cat ownership is common in Chile, but data on the regional prevalence of infectious agents are limited. A sero-molecular survey of 120 client- or shelter-owned domestic cats in greater Santiago was performed. Whole blood DNA was tested for the novel hepatitis-B-like virus, domestic cat hepadnavirus (DCH) by conventional PCR (cPCR) and quantitative PCR (qPCR), and for feline leukaemia virus (FeLV) by qPCR. Point-of-care serology for FeLV p27 antigen and antibodies recognising feline immunodeficiency virus (FIV) p15 and p24 was performed. DCH DNA was detected in the serum of 2/120 cats (1.67%). Sequencing and phylogenetic analysis showed that the DCH detected in Chile occupies a position outside the main clustering of DCH in the near-complete genome tree. Progressive (antigen-positive, provirus-positive) and regressive (antigen-negative, provirus-positive) FeLV infections were identified in 6/120 (5%) and 9/120 (7.5%) of cats. A total of 2/120 (1.7%) cats had dual FeLV/FIV infection, and another 2 cats had FIV infection alone. This study shows that the global footprint of DCH includes South America with a low molecular frequency in Chile, similar to that reported in the USA. Progressive FeLV infection is relatively common in urban Chile, and male cats are at greater risk than females. Testing and control measures for pathogenic retroviruses are indicated. The potential impact of FeLV, FIV and DCH on Chile's wildcat species is worthy of further investigation.
Assuntos
Hepadnaviridae , Vírus da Imunodeficiência Felina , Leucemia Felina , Humanos , Feminino , Gatos , Animais , Retroviridae , Chile/epidemiologia , Filogenia , Vírus da Leucemia Felina/genética , Vírus da Imunodeficiência Felina/genética , DNARESUMO
Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are globally distributed retroviruses that infect domestic cats and cause various syndromes that can lead to death. The aim of this study was to detect and genotype feline retroviruses in Mexican domestic cats. We used PCR assays to identify proviral DNA and viral RNA in 50 domestic cats with different clinical signs and hematological alterations. Endogenous FeLV (enFeLV) was identified in the genomic DNA of all cats in the study, and we detected transcripts of the LTR region of enFeLV in 48 individuals. Exogenous FeLV (exFeLV) was found in 13 cats. Furthermore, we detected FIV proviral DNA in 10 cats. The enFeLV sequences were shown to be the most variable, while the exFeLV sequences were highly conserved and related to previously reported subgroup A sequences. Sequencing of the FIV gag gene revealed the presence of subtype B in the infected cats.
Assuntos
Vírus da Imunodeficiência Felina , Leucemia Felina , Gatos , Animais , Retroviridae , Vírus da Leucemia Felina/genética , Provírus/genética , Vírus da Imunodeficiência Felina/genéticaRESUMO
The surface envelope (SU) protein determines the cell tropism and consequently the pathogenesis of the feline leukemia virus (FeLV) in felids. Recombination of exogenous FeLV (exFeLV) with endogenous retroviruses (enFeLV) allows the emergence of more pathogenic variants. Currently, phenotypic testing through interference assays is the only method to distinguish among subgroups-namely, FeLV-A, -B, -C, -E, and -T. This study proposes a new method for FeLV classification based on molecular analysis of the SU gene. A total of 404 publicly available SU sequences were used to reconstruct a maximum likelihood tree. However, only 63 of these sequences had available information about phenotypic tests or subgroup assignments. Two major clusters were observed: (a) clade FeLV-A, which includes FeLV-A, FeLV-C, FeLV-E, and FeLV-T sequences, and (b) clade enFeLV, which includes FeLV-B and enFeLV strains. We found that FeLV-B, FeLV-C, FeLV-E, and FeLV-T SU sequences share similarities to FeLV-A viruses and most likely arose independently through mutation or recombination from this strain. FeLV-B and FeLV-C arose from recombination between FeLV-A and enFeLV viruses, whereas FeLV-T is a monophyletic subgroup that has probably originated from FeLV-A through combined events of deletions and insertions. Unfortunately, this study could not identify polymorphisms that are specifically linked to the FeLV-E subgroup. We propose that phylogenetic and recombination analysis together can explain the current phenotypic classification of FeLV viruses.
Assuntos
Vírus da Leucemia Felina/classificação , Filogenia , Bases de Dados Genéticas , Geografia , Vírus da Leucemia Felina/genética , Mutação , Recombinação Genética , Proteínas do Envelope Viral/genéticaRESUMO
The feline leukemia virus (FeLV) belongs to the family Retroviridae; it is the first feline retrovirus discovered and one of the agents that has a great impact on cats' health and the ecology of the feline population worldwide. It is associated with the occurrence of several syndromes of fatal diseases, including the development of lymphomas. Studies on FeLV have been reported in Colombia, and most of them have been approached from a clinical point of view. However, only a few studies have focused on the prevalence of the infection, while none have clarified which variant or FeLV viral subgroup is presently circulating in our country. Therefore, the present study investigated the prevalence of the infection associated with the molecular characterization of FeLV present in cats in Aburrá Valley, Colombia. The sampling of privately owned and shelter cats was performed in female (n = 54) and male (n = 46) felines; most of them were seemingly healthy according to the owner's report, with nonspecific clinical history. Immunoassay confirmed that 59.44% (95% confidence interval (CI) = 49.81-69.06%) of felines were FeLV seropositive. The molecular testing of felines using reverse transcription-polymerase chain reaction and sequencing showed that 30% (30/100) of felines were positive, and the most prevalent subgroup in the Aburrá Valley was FeLV-A. In conclusion, the frequency of leukemia virus, as revealed by molecular and serological tests, is one of the highest reported frequencies to date, and a high molecular variation is shown in the Colombian population. More studies on the behaviour of the virus in feline populations in Columbia are warranted to determine its prevalence throughout the country.
Assuntos
Genoma Viral , Genômica , Vírus da Leucemia Felina/genética , Leucemia Felina/epidemiologia , Leucemia Felina/virologia , Animais , Gatos , Colômbia/epidemiologia , Estudos Transversais , Feminino , Variação Genética , Genômica/métodos , Geografia Médica , Vírus da Leucemia Felina/classificação , Leucemia Felina/diagnóstico , Masculino , Filogenia , Reação em Cadeia da Polimerase , PrevalênciaRESUMO
Feline leukemia virus (FeLV) infection causes immunosuppression, degeneration of the hematopoietic system, and fatal neoplasms. FeLV transmission occurs mainly by close social contact of infected and susceptible cats. Developing procedures for the diagnosis of feline retroviruses is crucial to reduce negative impacts on cat health and increase the number of animals tested. Blood collection requires physical or chemical restraint and is usually a stressful procedure for cats. Our objective was to evaluate the use of samples obtained from oral, conjunctival, and rectal mucosae for the molecular diagnosis of FeLV. Whole blood and oral, conjunctival, and rectal swabs were collected from a total of 145 cats. All samples were subjected to the amplification of a fragment of the gag gene of proviral DNA. Compared to blood samples used in this study as a reference, the accuracies for each PCR were 91.72, 91.23, and 85.50% for samples obtained by oral, conjunctival, and rectal swabs, respectively. The diagnostic sensitivity and specificity were 86.11 and 97.26% for the oral swabs, 90 and 92.59% for the conjunctival swabs, and 74.24 and 95.77% for the rectal swabs, respectively. The kappa values for oral, conjunctival, and rectal swabs were 0.834, 0.824, and 0.705, respectively. The diagnosis of these samples showed the presence of proviral DNA of FeLV in oral and conjunctival mucosae. In conclusion, mucosal samples for the molecular diagnosis of FeLV are an excellent alternative to venipuncture and can be safely used. It is faster, less laborious, less expensive, and well received by the animal.