RESUMO
During the Zika virus (ZIKV) outbreak in Brazil (2015-2016), the clinical manifestations associated with its infection were complex and included miscarriage and congenital malformations, not previously described. In this study, we evaluated the prenatal conditions of pregnant female squirrel monkeys (Saimiri collinsi) infected during different gestational thirds (GTs) and assessed all clinical aspects, diagnostic imaging, viremia and the immune response. In our study, 75% of the infected animals in the 1st GT group had significant clinical manifestations, such as miscarriage and prolonged viremia associated with a late immune response. Consequently, their neonates showed fetal neuropathology, such as cerebral hemorrhage, lissencephaly or malformations of the brain grooves, ventriculomegaly, and craniofacial malformations. Thus, our study demonstrated the relevance of pregnant squirrel monkeys as a model for the study of ZIKV infection in neonates due to the broad clinical manifestations presented, including the typical congenital Zika syndrome manifestations described in humans.
Assuntos
Doenças Fetais , Microcefalia , Doenças dos Macacos , Saimiri/virologia , Infecção por Zika virus , Zika virus/metabolismo , Animais , Brasil/epidemiologia , Feminino , Doenças Fetais/epidemiologia , Doenças Fetais/metabolismo , Doenças Fetais/veterinária , Doenças Fetais/virologia , Microcefalia/embriologia , Microcefalia/metabolismo , Microcefalia/virologia , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/metabolismo , Doenças dos Macacos/virologia , Gravidez , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/metabolismo , Infecção por Zika virus/veterináriaRESUMO
UNLABELLED: Rotaviruses (RVs) enter cells through different endocytic pathways. Bovine rotavirus (BRV) UK uses clathrin-mediated endocytosis, while rhesus rotavirus (RRV) employs an endocytic process independent of clathrin and caveolin. Given the differences in the cell internalization pathway used by these viruses, we tested if the intracellular trafficking of BRV UK was the same as that of RRV, which is known to reach maturing endosomes (MEs) to infect the cell. We found that BRV UK also reaches MEs, since its infectivity depends on the function of Rab5, the endosomal sorting complex required for transport (ESCRT), and the formation of endosomal intraluminal vesicles (ILVs). However, unlike RRV, the infectivity of BRV UK was inhibited by knocking down the expression of Rab7, indicating that it has to traffic to late endosomes (LEs) to infect the cell. The requirement for Rab7 was also shared by other RV strains of human and porcine origin. Of interest, most RV strains that reach LEs were also found to depend on the activities of Rab9, the cation-dependent mannose-6-phosphate receptor (CD-M6PR), and cathepsins B, L, and S, suggesting that cellular factors from the trans-Golgi network (TGN) need to be transported by the CD-M6PR to LEs to facilitate RV cell infection. Furthermore, using a collection of UK × RRV reassortant viruses, we found that the dependence of BRV UK on Rab7, Rab9, and CD-M6PR is associated with the spike protein VP4. These findings illustrate the elaborate pathway of RV entry and reveal a new process (Rab9/CD-M6PR/cathepsins) that could be targeted for drug intervention. IMPORTANCE: Rotavirus is an important etiological agent of severe gastroenteritis in children. In most instances, viruses enter cells through an endocytic pathway that delivers the viral particle to vesicular organelles known as early endosomes (EEs). Some viruses reach the cytoplasm from EEs, where they start to replicate their genome. However, other viruses go deeper into the cell, trafficking from EEs to late endosomes (LEs) to disassemble and reach the cytoplasm. In this work, we show that most RV strains have to traffic to LEs, and the transport of endolysosomal proteases from the Golgi complex to LEs, mediated by the mannose-6-phosphate receptor, is necessary for the virus to exit the vesicular compartment and efficiently start viral replication. We also show that this deep journey into the cell is associated with the virus spike protein VP4. These findings illustrate the elaborate pathway of RV entry that could be used for drug intervention.
Assuntos
Catepsinas/metabolismo , Doenças dos Bovinos/enzimologia , Doenças dos Bovinos/virologia , Endossomos/virologia , Doenças dos Macacos/enzimologia , Receptor IGF Tipo 2/metabolismo , Infecções por Rotavirus/veterinária , Rotavirus/fisiologia , Animais , Catepsinas/genética , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/metabolismo , Endossomos/enzimologia , Endossomos/metabolismo , Macaca mulatta , Camundongos , Doenças dos Macacos/genética , Doenças dos Macacos/metabolismo , Doenças dos Macacos/virologia , Receptor IGF Tipo 2/genética , Rotavirus/genética , Infecções por Rotavirus/enzimologia , Infecções por Rotavirus/metabolismo , Infecções por Rotavirus/virologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Internalização do VírusRESUMO
Fasted Bolivian squirrel monkeys (BoSM) exhibit a marked hyperbilirubinemia when compared to fed BoSM. This fasting hyperbilirubinemia (FH) is similar to that in human patients with Gilbert's syndrome. Endogenous bilirubin (BR) excretion (production) into bile was elevated two-fold in BoSM upon fasting. The fraction of injected dose of 3 H-amino-levulinic acid (ALA) incorporated into biliary BR in fasted monkeys was of less magnitude than in fed monkeys and was associated with lower specific activities of 3 H-BR. Both the lower incorporation of ALA and lower specific activities of 3H-BR in fasted BoSM suggest that increased BR excreted may have arisen from pre-existing non-labeled pools of either heme or BR.
Assuntos
Bile/metabolismo , Bilirrubina/metabolismo , Doença de Gilbert/veterinária , Doenças dos Macacos/metabolismo , Saimiri , Ácido Aminolevulínico , Animais , Bile/química , Bilirrubina/análise , Bilirrubina/sangue , Bolívia , Feminino , Doença de Gilbert/metabolismo , MasculinoRESUMO
Pulmonary carbon monoxide (CO) excretion rates (VeCO) were 50% greater, on average, in Bolivian squirrel monkeys (BoSMs) which exhibit a unique fasting hyperbilirubinemia (FH), than in fasted control Brazilian squirrel monkeys (BrSMs). Since the catabolism of heme produces equimolar amounts of CO and bilirubin, the increased VeCOs are consistent with concurrent increases in endogenous bilirubin production rates. Tin-protoporphyrin, a competitive inhibitor of heme oxygenase, significantly decreased both the VeCO and serum bilirubin level in fasted BoSMs. Overproduction of bilirubin may be responsible in part for the marked FH in BoSMs.