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Reducing lactate accumulation has always been a goal of the mammalian cell biotechnology industry. When animal cells are cultured in vitro, the accumulation of lactate is mainly the combined result of two metabolic pathways. On one hand, glucose generates lactate under the function of lactate dehydrogenase A (LDHA); on the other hand, lactate can be oxidized to pyruvate by LDHB or LDHC and re-enter the TCA cycle. This study comprehensively evaluated the effects of LDH manipulation on the growth, metabolism and human adenovirus (HAdV) production of human embryonic kidney 293 (HEK-293) cells, providing a theoretical basis for engineering the lactate metabolism in mammalian cells. By knocking out ldha gene and overexpression of ldhb and ldhc genes, the metabolic efficiency of HEK-293 cells was effectively improved, and HAdV production was significantly increased. Compared with the control cell, LDH manipulation promoted cell growth, reduced the accumulation of lactate and ammonia, significantly enhanced the efficiency of substrate and energy metabolism of cells, and significantly increased the HAdV production capacity of HEK-293 cells. Among these LDH manipulation measures, ldhc gene overexpression performed the best, with the maximum cell density increased by about 38.7%. The yield of lactate to glucose and ammonia to glutamine decreased by 33.8% and 63.3%, respectively; and HAdV titer increased by at least 16 times. In addition, the ATP production rate, ATP/O2 ratio, ATP/ADP ratio and NADH content of the modified cell lines were increased to varying degrees, and the energy metabolic efficiency was significantly improved.
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Animais , Humanos , L-Lactato Desidrogenase/genética , Ácido Láctico , Adenovírus Humanos , Amônia , Células HEK293 , Glucose/metabolismo , Trifosfato de Adenosina/metabolismo , Rim/metabolismo , Mamíferos/metabolismoRESUMO
ABSTRACT Human Adenovirus 36 (HAdV-36) has been related to diverse effects on metabolism and may attenuate the lipid accumulation in kidneys with increased adiposity. Some of these effects would be related to viral persistence. However, until now, a model of persistent in vitro infection by HAdV-36 is unknown. In this study, we examined the cells of the Vero lineage to explore their permissiveness to long-term HAdV-36 infection. HAdV-36 was productively replicated in Vero cells and maintained long-term infection for up to 35 cell passages. A subculture was obtained from the cells that survived the primary infection at a low MOI (0.5). The production of the extracellular infectious virus with titers ranging from 104 to 106 TCID50/mL and DNA-bearing cells was detected. In long-term infected cells, the intracellular distribution of viral antigen was demonstrated by performing immunolocalization (IFI) and expression of cell-viral antigen in 50% of cells by flow cytometry, using anti-HAdV-36 hyperimmune rabbit serum. Furthermore, E1a and E4orf1 genes in long-term infected passages showed a decreasing trend. Our preliminary results reveal that renal epithelial monkey cells are permissive for the productive infection of HAdV-36. Vero cell culture long-term infection might be a promising model for addressing the fundamental aspects of the HAdV-36 biology that cannot reveal broadly-used cultures, which do not maintain long-term infection in primary or transformed cells.
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Objective To analyze the type and gene features of 11 unverified HAdVs in China. Methods We downloaded HAdV genome sequences of 67 strains with clear genotypes and the HAdV reference genome sequences of 7 strains from GenBank database, analyzed them together with eleven unverified HAdV gene sequences and classified the species of each sequence based on the genetic structure, sequence similarity and phylogenetic analysis. Results Phylogenetic analysis results predicted the classification of six sequences: two of them belonged to HAdV-B and two belonged to HAdV-D (the gene homology were 97.8% and 92.8% in comparison with reference gene respectively), the rest of two sequences were not conclusive. Multiple sequence alignment was used to predict the species of five HAdVs. All of them belonged to species HAdV-B, the sequence similarity compared with reference gene was 97.9%. Conclusion Genotyping of the unverified HAdV genome from a genetic point of view predicts that seven strains might belong to species HAdV-B, two strains might belong to species HAdV-D and two strains could not be classified. The seven HAdV-B strains might be suitable for the treatment of osteosarcoma as oncolytic adenovirus.
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Human mastadenovirus (HAdV) genus is related to several diseases, among them upper and lower respiratory tract illness. HAdV species B, C, D, and E are mainly associated with respiratory infections. The goal of this work was to identify the HAdV species associated with respiratory infections in hospitalized patients from southern Brazil. Samples were collected from 1996 to 2004 and 2011 to 2017. During this period, 28,524 samples were collected, and 9983 were positive for respiratory viruses, being 435 for HAdV. From these 435 samples, 57 were selected for characterization of HAdV species. For screening the presence of HAdV, a partial sequence of the DNA polymerase gene (DNApol gene) was amplified by nested PCR. Partial nucleotide sequencing was performed in positive samples, and HAdV (DNApol gene) was detected in 53 samples: species B (28;49.1%), C (16;8.0%), D (2; 3.5%), E (5; 8.7%), and untyped (2; 3.5%). Specie D was found only in 2017 and specie E in 2011 and 2012. The age of the patients ranged from < 1 to 81 years old, and 62.3%were male. No relationship between gender orage and identified HAdV species were observed. In addition, in the period of 20132017, 18 samples from patients who died were analyzed: 11 were related to species B, 4 to C, and 2 to D and 1 remained untyped. Circulation of HAdV species D and Evaried over the years, but species B and C were present throughout the evaluated period. In addition, respiratory infections by HAdVaffect elderly and children mainly. (AU)
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Humanos , Masculino , Feminino , Criança , Idoso , Idoso de 80 Anos ou mais , Sistema Respiratório , Infecções Respiratórias/virologia , Mastadenovirus/patogenicidade , Ácidos Nucleicos , MorbidadeRESUMO
Objective To investigate the variation characteristics of adenovirus type 55 (HAdV-B55) gene on plateaus.Methods Throat swabs were collected from HAdV-B55 infected patients and used for virus isolation in HEp-2 cells.The whole-genome sequence was obtained by PCR and sequencing.HAdV-B55 gene sequence was blast with the previously reported virus.Results HAdV-B55 strains were isolated from throat swabs, which were named LS89/Tibet/2016.The whole-genome sequence was obtained and submitted to GenBank with the accession number of KY002683.No large fragment gene recombination was found between this HAdV-B55 strain and previous strains, and the sequence similarity with QS-DLL strain was 99.9%.Conclusion This study provides more information for the evolution patterns of adenovirus 55 and will contribute to the prevention and control of HAdV-B55 infection in the future.
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Human adenoviruses (HAdV), members of the
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Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , Fezes/virologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/classificação , Brasil , Norovirus/genética , Norovirus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Rotavirus/genética , Rotavirus/isolamento & purificação , Estações do AnoRESUMO
INTRODUCTION: Human adenoviruses (HAdV) play an important role in the etiology of severe acute lower respiratory infection, especially in immunocompromised individuals. The aim of the present study was detect the HAdV through different methods: direct fluorescence assay (DFA) and nested-polymerase chain reaction (PCR-nested) from patients with acute respiratory infection (ARI) up to 7 days of symptoms onset. METHODS: Samples (n=643) were collected from different risk groups during from 2001 to 2010: 139 adults attended in an Emergency Room Patients (ERP); 205 health care workers (HCW); 69 from Renal Transplant Outpatients (RTO); 230 patients in hematopoietic stem cell transplantation (HSCT) program. RESULTS: Among all patients (n=643) adenovirus was detected on 13.2% by DFA and/or PCR: 6/139 (4.3%) adults from ERP, 7/205 (3.4%) from HCW samples, 4/69 (5.8%) from RTO and 68/230 (29.5%) from HSCT patients. Nested PCR showed higher detection (10%) compared to DFA test (3.8%) (p < 0.001). HSCT patients presented significantly higher prevalence of HAdV infection. CONCLUSIONS: Adenovirus detection through nested-PCR assay was higher. However the inclusion of molecular method in laboratorial routine diagnostic should be evaluated considering the reality of each specific health service. .