RESUMO
Bovines infected by bovine leukemia virus (BLV) are characterized by presenting low proviral load (LPL) or high proviral load (HPL). It is reported that animals with HPL in peripheral blood mononuclear cells (PBMCs) present a decrease in apoptosis, an increase in viability and the proliferation rate, while animals that maintain an LPL have an intrinsic ability to control the infection, presenting an increased apoptosis rate of their PBMCs. However, there is little information on the effect of BLV on these mechanisms when the virus infects somatic milk cells (SC). This study investigates the mechanisms underlying apoptosis in milk and blood from BLV-infected animals with HPL and LPL. Relative levels of mRNA of tumor necrosis factor-α (TNF-α), TNF receptor 1 (TNF-RI), TNF receptor 2 (TNF-RII), anti-apoptotic B-cell lymphoma 2 protein (Bcl-2), and pro-apoptotic Bcl-2-like protein 4 (Bax) were measured in SC and PBMCs using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) assay. A significant decrease in the expression of TNF-α in SC from HPL animals vs non-infected bovines was observed, but the infection in SC with BLV did not show a modulation on the expression of TNF receptors. A significant increase in TNF-RI expression in PBMCs from HPL bovines compared to LPL bovines was observed. No significant differences in PBMCs between HPL and LPL compared to non-infected animals concerning TNF-α, TNF-RI, and TNF-RII expression were found. There was a significant increase of both Bcl-2 and Bax in SC from LPL compared to non-infected bovines, but the Bcl-2/Bax ratio showed an anti-apoptotic profile in LPL and HPL bovines compared to non-infected ones. Reduced mRNA expression levels of Bax were determined in the PBMCs from HPL compared to LPL subjects. In contrast, BLV-infected bovines did not differ significantly in the mRNA expression of Bax compared to non-infected bovines. Our data suggest that the increased mRNA expression of Bax corresponds to the late lactation state of bovine evaluated and the exacerbated increase of mRNA expression of Bcl-2 may be one of the mechanisms for the negative apoptosis regulation in the mammary gland induced by BLV infection. These results provide new insights into the mechanism of mammary cell death in HPL and LPL BLV-infected bovine mammary gland cells during lactation.
Assuntos
Doenças dos Bovinos , Leucose Enzoótica Bovina , Vírus da Leucemia Bovina , Animais , Bovinos , Feminino , Apoptose , Proteína X Associada a bcl-2/metabolismo , Proliferação de Células , Leucócitos Mononucleares/metabolismo , Leite , Provírus/genética , Provírus/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Type III interferons (IFNs) are components of the innate immunity, with IFN lambda- (λ)3 having the most potent bioactivity in humans. IFN-λ has a predominant role in epithelial cells. However, antiviral function in certain infections of the central nervous system has also been demonstrated. IFN-λ3 expression in neural tissues of cattle has not been investigated. Thus, the aim of this study was to analyze whether an antiviral IFN-λ3 response is mounted after infection with bovine alphaherpesviruses (BoHV-1 and BoHV-5) in vitro, in neuronal-type cells, and in neural tissues from experimentally-infected calves. This study demonstrated that there is a strong IFN-λ3 response early after BoHV-1infection of undifferentiated neuroblastoma cells. During acute BoHV-1 and BoHV-5 infection of calves, low levels of IFN-λ3 expression were detected in the brain, which would favor virus spread within this tissue. Striking differences in the transcriptional levels of IFN-λ3 were observed in trigeminal ganglion, particularly in BoHV-1-acutely- and latently-infected calves. During reactivation, IFN-λ3 expression was down-regulated, which may be a requirement for virus replication and spread. Overall, different patterns of IFN-λ3 expression were detected during BoHV-1 and BoHV-5 infection, particularly during latency.
Assuntos
Doenças dos Bovinos , Infecções por Herpesviridae , Herpesvirus Bovino 1 , Animais , Bovinos , Infecções por Herpesviridae/veterinária , Interferons , Gânglio Trigeminal , Replicação ViralRESUMO
OBJECTIVE: The characterization in the discursive space of 27 users of the "Consultorio Juvenil" (young peoples' clinic), their critical areas with regard to themes, actors, actions, values and situational perception schemes. METHOD: Qualitative study with the use of semiotic analysis. Analysis was made in three steps: description of manifest text structure; codification in the quest for isotopes and internal organization analysis. RESULTS: There is clear differentiation between themes and means by gender; girls are more fully integrated into intrafamily relationships and boys into extrafamily ones. Formal engagement is a central theme for young women, while sexuality is for young men. In women a moral situation exercises influence over ethical criteria in the making of decisions; men show an individualist ethic. Both perceive problems as external, foreign to them, as part of their fate. CONCLUSIONS: Social gender formation influences the critical areas, creating myths and behavior stereotypes. The tendency to see the problem as imposed can signify a health risk for adolescents.