RESUMEN
Obesity is increasing in incidence worldwide, especially in women, which can affect the outcome of pregnancy. During this period, viral infections represent a risk to the mother, the placental unit, and the fetus. The Zika virus (ZIKV) outbreak in Brazil has been the cause of congenital Zika syndrome (CZS), with devastating consequences such as microcephaly in newborns. Herein, we analyzed the impact of maternal overweight/obesity on the antiviral factors' expression in the placental tissue of Zika-infected mothers. We accessed placentas from women with and without obesity from 34 public health units (São Paulo) and from Zika-infected mothers with and without obesity from the Clinical Cohort Study of ZIKV pregnant women (Rio de Janeiro, Brazil). We first verified that obesity, without infection, did not alter the constitutive transcriptional expression of antiviral factors or IFN type I/III expression. Interestingly, obesity, when associated with ZIKV infection, showed a decreased transcriptional expression of RIG-I and IFIH1 (MDA-5 protein precursor gene). At the protein level, we also verified a decreased RIG-I and IRF-3 expression in the decidual placenta from the Zika-infected obese group, regardless of microcephaly. This finding shows, for the first time, that obesity associated with ZIKV infection leads to an impaired type I IFN downstream signaling pathway in the maternal-fetal interface.
Asunto(s)
Interferón Tipo I , Microcefalia , Infección por el Virus Zika , Virus Zika , Recién Nacido , Embarazo , Femenino , Humanos , Antivirales , Mujeres Embarazadas , Infección por el Virus Zika/complicaciones , Estudios de Cohortes , Brasil/epidemiología , Placenta , ObesidadRESUMEN
We evaluated the presence of antibodies for rabies virus in 177 serum samples from 125 wild lowland tapirs (Tapirus terrestris) from three different Brazilian biomes. The rapid fluorescent focus inhibition test was performed. No antibody titers suggesting the circulation of the rabies virus in tapir habitat were detected.
Asunto(s)
Ecosistema , Perisodáctilos/sangre , Virus de la Rabia , Rabia/veterinaria , Animales , Anticuerpos Antivirales/sangre , Brasil/epidemiología , Rabia/epidemiología , Rabia/virología , Estudios SeroepidemiológicosRESUMEN
Rabies is a fatal and viral zoonosis that causes acute, progressive encephalitis and remains an important concern in public health. In the last few years, there has been a change in the epidemiological profile of rabies after implementing canine rabies control in the Americas, which has led to a significant increase in both human and pet cases of rabies associated with insectivorous bats. Thus, it is important to understand the pathogenesis caused by Rabies virus (RABV) isolates from insectivorous bats. Viral growth kinetics, cell-to-cell spread and virus uptake in vitro were analyzed for RABV isolates from Eptesicus furiralis and Myotis nigricans. For pathogenesis evaluation, mice were inoculated with RABV isolates from Eptesicus furiralis and Myotis nigricans, and clinical signs were observed for 40 days. We observed that the insectivorous bat strains showed a higher replication rate, faster cell-to-cell spread and delayed virus uptake in N2a cells. Furthermore, after the first sign of a clinical infection, mice infected with Myotis nigricans and Eptesicus furiralis isolates succumbed rapidly (6⯱â¯9 days) compared with RABV strains associated with other reservoirs. Our results show that the insectivorous bat RABV strains are less pathogenic for mice than strains associated with other reservoirs. In addition, this study also indicates that the differences in the biological characteristics of the RABV strains are important to their pathogenicity. An enhanced understanding of rabies pathogenesis may be important for the development of novel therapies for humans and in the implementation of rabies control strategies. (AU)
Asunto(s)
Humanos , Animales , Virus de la Rabia/patogenicidad , Rabia/prevención & control , Replicación Viral , Zoonosis , Quirópteros/virologíaRESUMEN
Rabies is a fatal and viral zoonosis that causes acute, progressive encephalitis and remains an important concern in public health. In the last few years, there has been a change in the epidemiological profile of rabies after implementing canine rabies control in the Americas, which has led to a significant increase in both human and pet cases of rabies associated with insectivorous bats. Thus, it is important to understand the pathogenesis caused by Rabies virus (RABV) isolates from insectivorous bats. Viral growth kinetics, cell-to-cell spread and virus uptake in vitro were analyzed for RABV isolates from Eptesicus furiralis and Myotis nigricans. For pathogenesis evaluation, mice were inoculated with RABV isolates from Eptesicus furiralis and Myotis nigricans, and clinical signs were observed for 40 days. We observed that the insectivorous bat strains showed a higher replication rate, faster cell-to-cell spread and delayed virus uptake in N2a cells. Furthermore, after the first sign of a clinical infection, mice infected with Myotis nigricans and Eptesicus furiralis isolates succumbed rapidly (6⯱â¯9 days) compared with RABV strains associated with other reservoirs. Our results show that the insectivorous bat RABV strains are less pathogenic for mice than strains associated with other reservoirs. In addition, this study also indicates that the differences in the biological characteristics of the RABV strains are important to their pathogenicity. An enhanced understanding of rabies pathogenesis may be important for the development of novel therapies for humans and in the implementation of rabies control strategies.
Asunto(s)
Quirópteros/virología , Virus de la Rabia/patogenicidad , Rabia/patología , Rabia/virología , Animales , Modelos Animales de Enfermedad , Ratones , Virus de la Rabia/crecimiento & desarrollo , Virus de la Rabia/aislamiento & purificación , Análisis de Supervivencia , Factores de Tiempo , Virulencia , Internalización del Virus , Liberación del Virus , Replicación ViralRESUMEN
Rabies is a lethal viral infection that can affect almost all mammals, including humans. To better understand the replication of Rabies lyssavirus, we investigated if the viral load in brains naturally infected with rabies influences viral internalization and viral growth kinetics in neuroblastoma cells, and if the viral load affects mortality in mice after intradermal infection. We noted that high initial viral loads in brains (group II) were unfavourable for increasing viral titers during serial passages in neuroblastoma cells when compared to low initial viral loads in brains (group I). In addition, group I strains showed higher viral growth and enhanced internalization efficiency in neuroblastoma cells than group II strains. However, we observed that the dominant virus subpopulation in group II promoted efficient viral infection in the central nervous system in the new host, providing a selective advantage to the virus. Our data indicate that rabies infection in animal models depends on not only the virus strain but also the amount of virus. This study may serve as a basis for understanding the biologic proprieties of Rabies lyssavirus strains with respect to the effects on viral replication and the impact on pathogenesis, improving virus yields for use in vaccine development.
Asunto(s)
Virus de la Rabia/fisiología , Rabia/virología , Replicación Viral , Animales , Encéfalo/virología , Línea Celular Tumoral , Células Cultivadas , Ratones , Neuroblastoma , Carga Viral , Internalización del VirusRESUMEN
Rabies is a fatal and viral zoonosis that causes acute, progressive encephalitis and remains an important concern in public health. In the last few years, there has been a change in the epidemiological profile of rabies after implementing canine rabies control in the Americas, which has led to a significant increase in both human and pet cases of rabies associated with insectivorous bats. Thus, it is important to understand the pathogenesis caused by Rabies virus (RABV) isolates from insectivorous bats. Viral growth kinetics, cell-to-cell spread and virus uptake in vitro were analyzed for RABV isolates from Eptesicus furiralis and Myotis nigricans. For pathogenesis evaluation, mice were inoculated with RABV isolates from Eptesicus furiralis and Myotis nigricans, and clinical signs were observed for 40 days. We observed that the insectivorous bat strains showed a higher replication rate, faster cell-to-cell spread and delayed virus uptake in N2a cells. Furthermore, after the first sign of a clinical infection, mice infected with Myotis nigricans and Eptesicus furiralis isolates succumbed rapidly (6?±?9 days) compared with RABV strains associated with other reservoirs. Our results show that the insectivorous bat RABV strains are less pathogenic for mice than strains associated with other reservoirs. In addition, this study also indicates that the differences in the biological characteristics of the RABV strains are important to their pathogenicity. An enhanced understanding of rabies pathogenesis may be important for the development of novel therapies for humans and in the implementation of rabies control strategies.
RESUMEN
Rabies is a lethal viral infection that can affect almost all mammals, including humans. To better understand the replication of Rabies lyssavirus, we investigated if the viral load in brains naturally infected with rabies influences viral internalization and viral growth kinetics in neuroblastoma cells, and if the viral load affects mortality in mice after intradermal infection. We noted that high initial viral loads in brains (group II) were unfavourable for increasing viral titers during serial passages in neuroblastoma cells when compared to low initial viral loads in brains (group I). In addition, group I strains showed higher viral growth and enhanced internalization efficiency in neuroblastoma cells than group II strains. However, we observed that the dominant virus subpopulation in group II promoted efficient viral infection in the central nervous system in the new host, providing a selective advantage to the virus. Our data indicate that rabies infection in animal models depends on not only the virus strain but also the amount of virus. This study may serve as a basis for understanding the biologic proprieties of Rabies lyssavirus strains with respect to the effects on viral replication and the impact on pathogenesis, improving virus yields for use in vaccine development.
RESUMEN
Rabies is a fatal and viral zoonosis that causes acute, progressive encephalitis and remains an important concern in public health. In the last few years, there has been a change in the epidemiological profile of rabies after implementing canine rabies control in the Americas, which has led to a significant increase in both human and pet cases of rabies associated with insectivorous bats. Thus, it is important to understand the pathogenesis caused by Rabies virus (RABV) isolates from insectivorous bats. Viral growth kinetics, cell-to-cell spread and virus uptake in vitro were analyzed for RABV isolates from Eptesicus furiralis and Myotis nigricans. For pathogenesis evaluation, mice were inoculated with RABV isolates from Eptesicus furiralis and Myotis nigricans, and clinical signs were observed for 40 days. We observed that the insectivorous bat strains showed a higher replication rate, faster cell-to-cell spread and delayed virus uptake in N2a cells. Furthermore, after the first sign of a clinical infection, mice infected with Myotis nigricans and Eptesicus furiralis isolates succumbed rapidly (6?±?9 days) compared with RABV strains associated with other reservoirs. Our results show that the insectivorous bat RABV strains are less pathogenic for mice than strains associated with other reservoirs. In addition, this study also indicates that the differences in the biological characteristics of the RABV strains are important to their pathogenicity. An enhanced understanding of rabies pathogenesis may be important for the development of novel therapies for humans and in the implementation of rabies control strategies.
RESUMEN
Rabies is a lethal viral infection that can affect almost all mammals, including humans. To better understand the replication of Rabies lyssavirus, we investigated if the viral load in brains naturally infected with rabies influences viral internalization and viral growth kinetics in neuroblastoma cells, and if the viral load affects mortality in mice after intradermal infection. We noted that high initial viral loads in brains (group II) were unfavourable for increasing viral titers during serial passages in neuroblastoma cells when compared to low initial viral loads in brains (group I). In addition, group I strains showed higher viral growth and enhanced internalization efficiency in neuroblastoma cells than group II strains. However, we observed that the dominant virus subpopulation in group II promoted efficient viral infection in the central nervous system in the new host, providing a selective advantage to the virus. Our data indicate that rabies infection in animal models depends on not only the virus strain but also the amount of virus. This study may serve as a basis for understanding the biologic proprieties of Rabies lyssavirus strains with respect to the effects on viral replication and the impact on pathogenesis, improving virus yields for use in vaccine development.
RESUMEN
There are few studies on the role of innate immune response in dermatophytosis. An investigation was conducted to define the involvement of Toll-Like Receptors (TLRs) 2 and 4 in localized (LD) and disseminated (DD) dermatophytosis due to T. rubrum. Fifteen newly diagnosed patients, eight patients with LD and seven with DD, defined by involvement of at least three body segments were used in this study. Controls comprised twenty skin samples from healthy individuals undergoing plastic surgery. TLR2 and TLR4 were quantified in skin lesions by immunohistochemistry. A reduced expression of TLR4 in the lower and upper epidermis of both LD and DD patients was found compared to controls; TLR2 expression was preserved in the upper and lower epidermis of all three groups. As TLR4 signaling induces the production of inflammatory cytokines and neutrophils recruitment, its reduced expression likely contributed to the lack of resolution of the infection and the consequent chronic nature of the dermatophytosis. As TLR2 expression acts to limit the inflammatory process and preserves the epidermal structure, its preserved expression may also contribute to the persistent infection and limited inflammation that are characteristic of dermatophytic infections.
Asunto(s)
Queratinocitos/metabolismo , Tiña/metabolismo , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Tiña/patología , Adulto JovenRESUMEN
There are few studies on the role of innate immune response in dermatophytosis. An investigation was conducted to define the involvement of Toll-Like Receptors (TLRs) 2 and 4 in localized (LD) and disseminated (DD) dermatophytosis due to T. rubrum. Fifteen newly diagnosed patients, eight patients with LD and seven with DD, defined by involvement of at least three body segments were used in this study. Controls comprised twenty skin samples from healthy individuals undergoing plastic surgery. TLR2 and TLR4 were quantified in skin lesions by immunohistochemistry. A reduced expression of TLR4 in the lower and upper epidermis of both LD and DD patients was found compared to controls; TLR2 expression was preserved in the upper and lower epidermis of all three groups. As TLR4 signaling induces the production of inflammatory cytokines and neutrophils recruitment, its reduced expression likely contributed to the lack of resolution of the infection and the consequent chronic nature of the dermatophytosis. As TLR2 expression acts to limit the inflammatory process and preserves the epidermal structure, its preserved expression may also contribute to the persistent infection and limited inflammation that are characteristic of dermatophytic infections.
A literatura sobre o papel da resposta imune inata em dermatofitose é escassa. Este estudo se propôs a investigar a participação dos receptores do tipo Toll 2 e 4 (TLRs) 2 e 4 em pacientes com dermatofitose localizada (LD) e disseminada (DD, definida como lesões em pelo menos três segmentos corpóreos distintos), causadas por Trichophyton rubrum. Foram analisados cortes histológicos de 15 pacientes recém-diagnosticados, oito com LD e sete com DD. O grupo controle foi composto por 20 amostras de pele de indivíduos saudáveis submetidos a cirurgia plástica. TLR-2 e TLR-4 foram quantificados em lesões cutâneas por imunohistoquímica. Encontramos uma expressão reduzida de TLR-4 na epiderme superior e inferior nos dois grupos, LD e DD, quando comparados com o grupo controle; a expressão de TLR-2 foi preservada na epiderme superior e inferior de todos os três grupos. Como a sinalização por TLR-4 induz produção de citocinas inflamatórias e recrutamento de neutrófilos, a menor expressão desta molécula provavelmente contribui para a não resolução da infecção e conseqüente natureza persistente da dermatofitose. Como a sinalização via TLR-2 tem sido descrita como fator de regulação do processo inflamatório e de preservação da estrutura epidérmica, a sua expressão inalterada nas lesões dos pacientes com DD e DL pode contribuir também para a persistência da infecção e do reduzido processo inflamatório que são característicos das infecções por dermatófitos.
Asunto(s)
Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Queratinocitos/metabolismo , Tiña/metabolismo , /metabolismo , /metabolismo , Estudios de Casos y Controles , Inmunohistoquímica , Tiña/patologíaRESUMEN
Sarcoma de Kaposi (SK) é um tumor de origem vascular associado ao herpesvírus 8 humano (HHV-8). A incidência do SK-AIDS tem diminuído após o advento da terapia anti-retroviral combinada (HAART), sem estudos relacionando a resposta inflamatória cutânea e a expressão de HHV-8 na era pré e pós HAART. Utilizamos a immuno-histoquímica para caracterizar e quantificar in situ as células inflamatórias, o padrão de citocinas e a expressão de HHV-8 em lesões cutâneas de sarcoma de Kaposi clássico (SKC), sarcoma de Kaposi associado à AIDS (com ou sem HAART). O número diminuído de linfócitos TCD4+ em lesões de SK-AIDS quando comparado com SKC, reflete a imunodeficiência severa causada pelo HIV. O número de linfócitos TCD8+ foi similar nos três grupos de SK, o qual parece não se correlacionar com a forma clínico-epidemiológica do SK. As células S100+ e DD FXIIIa+ estiveram aumentadas em todas as lesões de SK comparadas com a pele normal. Nós também encontramos uma população celular dérmica S100+CD1a- peculiar nas lesões de SK. Os macrófagos CD68+ estiveram aumentados nas lesões de SKC quando comparados com as lesões de SK-AIDS, mas similares com aqueles encontrados em lesões de SK-AIDS/HAART. Dados semelhantes foram encontrados nas células de Langerhans epidérmicas nesses grupos, sugerindo uma recuperação immune parcial através da HAART. O número aumentado de células expressando IFN- em lesões de SKC e SK-AIDS/HAART quando comparado com SK-AIDS sugere essa citocina como um indicador de resposta imune mais eficaz. A expressão aumentada de IL-1 nas lesões de SKC e SK-AIDS/HAART poderia estar relacionada ao seu efeito anti-tumoral. A expressão de TNF-, IL-4 e IL-6 foram similares entre as lesões de SK avaliadas. Através de dupla marcação, a identificação nuclear de HHV-8 em DD FXIIIa+ sugere esse tipo celular como alvo para infecção por HHV-8. As lesões de SKC apresentaram número aumentado de células com expressão de HHV-8 quando comparado com os grupos de SK-AIDS...
Kaposis sarcoma (KS) is a vascular-originated tumor associated to human herpesvirus 8 (HHV-8). The incidence of AIDS-KS has decreased after the advent of highly active antiretroviral therapy (HAART), without studies regarding cutaneous inflammatory response and HHV-8 expression in pre- and post-HAART era. We used immunohistochemistry to characterize and to quantify in situ inflammatory cells, its cytokines pattern and the expression of HHV-8 in cutaneous lesions of classic Kaposis sarcoma (CKS), AIDS associated Kaposis sarcoma (with or without HAART). The decreased number of T CD4+ lymphocytes in lesions of AIDS-KS as compared with CKS, reflect the severe immunodeficiency caused by HIV. T CD8+ lymphocytes numbers were similar in three KS groups, which appeared unrelated to the clinical or epidemiological type of KS. S100+ cells and FXIIIa+ DD were increased in all KS lesions as compared with normal skin. We also found a peculiar dermal cellular population in KS lesions. CD68+ macrophages were higher in CKS lesions as compared with AIDS-KS lesions, but similar to those found in lesions of HAART/AIDS-KS. Similar data were found in epidermal Langerhans cells in these groups, suggesting a partial immune recovery by HAART. The high number of cells expressing IFN- in CKS lesions and HAART/AIDS-KS as compared with AIDS-KS suggests that this cytokine may be a marker of effective immune response. The increased expression of IL-1 in CKS lesions and HAART/AIDS-KS could be related with its anti-tumor effect. Expression of TNF-, IL-4 e IL-6 were similar between KS lesions. Demonstrated by double-immunostaining, nuclear identification of HHV-8 in FXIIIa+ DD suggests this cell type as target for HHV-8 infection. CKS lesions showed increased number of cells with HHV-8 expression as compared with another groups of AIDS-KS, independent of HAART. Our data shown that there was a partial recovery of local immune response in HAART/AIDS-KS lesions...