E7 Oncogene HPV58 Variants Detected in Northeast Brazil: Genetic and Functional Analysis.

Cervical cancer is associated with persistent infections by high-risk Human Papillomavirus (HPV) types that may have nucleotide polymorphisms and, consequently, different oncogenic potentials. Therefore, this study aimed to evaluate the genetic variability and structural effects of the E7 oncogene of HPV58 in cervical scraping samples from Brazilian women. The study was developed with patients from hospitals in the metropolitan area of Recife, PE, Brazil. The most frequent HPV types were, in descending order of abundance, HPV16, 31, and 58. Phylogenetic analysis demonstrated that the isolates were classified into sublineages A2, C1, and D2. Two positively selected mutations were found in E7: 63G and 64T. The mutations G41R, G63D, and T64A in the E7 protein reduced the stability of the protein structure. Utilizing an NF-kB reporter assay, we observed a decrease in the NK-kB pathway activity with the HPV58-E7 variant 54S compared to the WT E7. The other detected E7 HPV58 variants presented similar NF-kB pathway activity compared to the WT E7. In this study, it was possible to identify mutations that may interfere with the molecular interaction between the viral oncoproteins and host proteins.

Immunoinformatics applications in the development of therapeutic vaccines against human papillomavirus-related infections and cervical cancer.

The human papillomavirus (HPV) represents the most prevalent sexually transmitted infectious agent worldwide. HPV penetrates the epithelium through microlesions and establishes an infectious focus that can lead to the development of cervical cancer. Prophylactic HPV vaccines are available, but do not affect already-established infections. Using in silico prediction tools is a promising strategy for identifying and selecting vaccine candidate T cell epitopes. An advantage of this strategy is that epitopes can be selected according to the degree of conservation within a group of antigenic proteins. This makes achieving comprehensive genotypic coverage possible with a small set of epitopes. Therefore, this paper revises the general characteristics of HPV biology and the current knowledge on developing therapeutic peptide vaccines against HPV-related infections and cervical cancer.

Genomic constellations of RVA detected in Brazil from 1986 to 2016: a temporal and geographical distribution and occurrence of reassortments / Constelações genômicas de RVA detectadas no Brasil de 1986 a 2016: uma distribuição temporal e geográfica e ocorrência de rearranjos

INTRODUCTION: Species A rotavirus (RVA) infections are a major cause of severe gastroenteritis in children of <5 years worldwide. In Brazil, before vaccination, RVA was associated with 3.5 million episodes of acute diarrheal disease per year. Due to the segmented nature of their genomes, rotaviruses can exchange genes during co-infections, and generate new virus strains and new reinfections. OBJECTIVE: To evaluate the genomic diversity of RVA isolated in Brazil in 30 years, between 1986 to 2016, to investigate possible changes in the frequency of genotype constellations before and after the implementation of the vaccine. METHODS: In total, 4,474 nucleotide sequences were obtained from the Virus Variation Database. Genomic constellation was compared, and the proportion of rotavirus genotypes was analyzed by time and geographic region. RESULTS: Our results showed that major known genotypes were circulating in the country during the period under analysis, with a prevalence of the G1P[8] Wa-like genotype, decreasing only in the period immediately after the introduction of the vaccine. Regarding the geographical distribution, most of our constellations, 62 (39.2%), and 50 (31.6%) were concentrated in the North and Northeast regions. Our analysis also showed the circulation of multiple strains during the periods when the DS-1-like and AU-1-like genotypes were co-circulating with the Wa-like genotype. CONCLUSION: Therefore, it is likely that inter-genogroup reassortments are still occurring in Brazil and so it is important to establish an efficient surveillance system to follow the emergence of novel reassorted strains that might not be targeted by the vaccine.

INTRODUÇÃO: As infecções por rotavírus A (RVA) são uma das principais causas de gastroenterite grave em crianças <5 anos em todo o mundo. No Brasil, antes da vacinação, o RVA estava associado a 3,5 milhões de episódios de diarreia aguda por ano. Devido à natureza segmentada de seus genomas, os rotavírus podem trocar genes durante as coinfecções, gerar novas cepas de vírus e novas reinfecções. OBJETIVO: Avaliar a diversidade genômica de RVA isolados no Brasil entre 1986 a 2016 para investigar possíveis alterações na frequência das constelações de genótipos antes e após a implantação da vacina. MÉTODOS: No total, 4.474 sequências de nucleotídeos foram obtidas do Banco de Dados de Variação de Vírus. A constelação genômica foi comparada e a proporção dos genótipos de rotavírus foi analisada por tempo e região geográfica. RESULTADOS: Nossos resultados mostraram que os principais genótipos conhecidos circulavam no país no período em análise, com prevalência do genótipo G1P[8] Wa-like, diminuindo apenas no período imediatamente após a introdução da vacina. Em relação à distribuição geográfica, a maioria das nossas constelações, 62 (39,2%) e 50 (31,6%), concentrava-se nas regiões Norte e Nordeste. Nossa análise também mostrou a circulação de cepas múltiplas durante os períodos em que os genótipos DS-1-like e AU-1-like estavam co-circulando com o genótipo Wa-like. CONCLUSÃO: Portanto, é provável que rearranjos inter-genogrupos ainda estejam ocorrendo no Brasil e por isso é importante estabelecer um sistema de vigilância eficiente para acompanhar o surgimento de novas cepas rearranjadas que podem não ser protegidas pela vacina.

In vitro evaluation of the antibacterial effect of Brazilian red propolis ethanol extract in the prevention of periodontal disease in dogs.

Dental plaque (DP) is found on the surface of teeth and comprises a community of microorganisms that form a structured biofilm. Bacteria present in DP are potential periodontal pathogens when there is an imbalance in the healthy oral environment, and are precursors of periodontal disease (PD). In dogs, the treatments, such as mechanical removal, are difficult and expensive to apply. Therefore, in order to seek new therapeutic alternatives to control dental plaque in dogs, Brazilian red propolis ethanol extract (RPEE) was tested to evaluate its antibacterial effect on bacteria isolated from DP of dogs without PD. DP was collected from the supragingival dental surfaces of 10 dogs. Bacterial isolates of DP were identified by PCR and sequencing of 16S rDNA gene. The RPEE was obtained using the ultrasound ethanol extraction technique, and the chemical composition was obtained by HPLC-DAD and UV-spectrophotometry. In total, 29 different bacteria belonging to five genera were identified. Formononetin, biochanin A, liquiritigenin and daidzein were the major constituents of the RPEE. The cytotoxic effect showed cell viability after 24 h above 50 % at all concentrations evaluated. The minimum inhibitory concentration was between 37.5 and 150.0 µg/mL for all bacterial isolates. The minimal bactericidal concentration was between 150 and 1200 µg/mL for Gram-positive and 300-1200 µg/mL for Gram-negative bacteria. The results are promising and suggest that RPEE has significant antibacterial potential against the bacteria present in the DP of healthy dogs. Although further studies are still needed, the results suggest RPEE might be safely used in the prevention of periodontal disease.

Third-Generation Vaccines: Features of Nucleic Acid Vaccines and Strategies to Improve Their Efficiency.

Gene immunization comprises mRNA and DNA vaccines, which stand out due to their simple design, maintenance, and high efficacy. Several studies indicate promising results in preclinical and clinical trials regarding immunization against ebola, human immunodeficiency virus (HIV), influenza, and human papillomavirus (HPV). The efficiency of nucleic acid vaccines has been highlighted in the fight against COVID-19 with unprecedented approval of their use in humans. However, their low intrinsic immunogenicity points to the need to use strategies capable of overcoming this characteristic and increasing the efficiency of vaccine campaigns. These strategies include the improvement of the epitopes' presentation to the system via MHC, the evaluation of immunodominant epitopes with high coverage against emerging viral subtypes, the use of adjuvants that enhance immunogenicity, and the increase in the efficiency of vaccine transfection. In this review, we provide updates regarding some characteristics, construction, and improvement of such vaccines, especially about the production of synthetic multi-epitope genes, widely employed in the current gene-based vaccines.

New insights into Canis familiaris papillomaviruses genetics and biology: Is the genetic characterization of CPV types and their variants an important clinical issue?

Canis familiaris papillomavirus (CPV) is a member of the Papillomaviridae family and is found in dogs. After infection, the host can remain asymtomatic or develop benign ephitelial neoplasms such as papillomas and pigmented viral plaques, which can progress to cancer, in the form of squamous cell carcinoma (SCC). In humans, 227 types of human papillomavirus (HPV) have been described, with a well-established risk classification for cancer development. In addition, it is also known that variants of some high-risk HPV types may present different risks in respect of SCC development. In dogs, however, only a few types of CPV have been identified, despite the growing interest in this area, and knowledge on the genetic characterization of CPV variants is still scarce. Recent studies of CPV have shown that, as with HPV, benign neoplasia can develop into cancer, but it is believed that there are many more types and variants still to be described. Therefore, the aim of this study was to describe the genetics and biology of CPV, with the focus on what is known about lesions, geographic localization, virus types and variants.

EntroPhylo: An entropy-based tool to select phylogenetic informative regions and primer design.

We present a novel entropy-based computational tool that selects phylogenetic informative genomic regions associated with degenerate primer design. This tool identifies proper phylogenetic markers and proposes suitable degenerate primers to amplify and sequence them. The algorithm calculates the entropy value per site, and the selected region is used for primer design. In order to evaluate the tool, sequences of bovine papillomavirus L1 gene were obtained. Once the molecular region was selected, the primers were designed by the software and used in a PCR reaction for viral detection. Three positive samples were tested with four different concentrations, and it was possible to detect the virus in all samples. The results show the applicability of a tool that can select informative regions for phylogenetic analysis and design primers to amplify and sequence these regions, becoming relevant for several studies focusing on pathogen detection, as well as phylogenetic and genetics studies of populations.

Prevalence of coinfections in women living with human immunodeficiency virus in Northeast Brazil

Abstract INTRODUCTION: Despite the success of antiretrovirals, human immunodeficiency virus (HIV) coinfections continue to cause mortality. We investigated the prevalence of coinfections in women with HIV/acquired immunodeficiency syndrome in Sergipe, Brazil. METHODS: We conducted a cross-sectional study. The coinfections investigated were syphilis, hepatitis B and C, toxoplasmosis, rubella, tuberculosis, and cytomegalovirus. RESULTS: Among the 435 women, 85 (19.5%) had coinfections. The most prevalent was HIV/syphilis, followed by tuberculosis, toxoplasmosis, hepatitis C, hepatitis B, and rubella. Additionally, 300 (96.2%) were seropositive for cytomegalovirus immunoglobulin G. CONCLUSIONS: Despite significant progress in the treatment for people with HIV, coinfections continued to affect this population.

Prevalence of coinfections in women living with human immunodeficiency virus in Northeast Brazil.

INTRODUCTION: Despite the success of antiretrovirals, human immunodeficiency virus (HIV) coinfections continue to cause mortality. We investigated the prevalence of coinfections in women with HIV/acquired immunodeficiency syndrome in Sergipe, Brazil. METHODS: We conducted a cross-sectional study. The coinfections investigated were syphilis, hepatitis B and C, toxoplasmosis, rubella, tuberculosis, and cytomegalovirus. RESULTS: Among the 435 women, 85 (19.5%) had coinfections. The most prevalent was HIV/syphilis, followed by tuberculosis, toxoplasmosis, hepatitis C, hepatitis B, and rubella. Additionally, 300 (96.2%) were seropositive for cytomegalovirus immunoglobulin G. CONCLUSIONS: Despite significant progress in the treatment for people with HIV, coinfections continued to affect this population.

Significant association between IL10-1082/-819 and TNF-308 haplotypes and the susceptibility to cervical carcinogenesis in women infected by Human papillomavirus.

Human papillomavirus (HPV) is responsible for high-grade cervical lesions and cervical cancer. The inflammation plays a key role in cervical cancer progression. In this context, studies propose an association between TNFα and IL10 SNPs and susceptibility to HPV infection. The present work aimed to investigate the possible association between IL10 and TNFα promoter polymorphisms and HPV infection in the cervical carcinogenesis risk in women from Brazil. A total of 654 samples was evaluated in this study. HPV detection was performed by PCR and HPV genotyping was performed by PCR and sequencing of positive MY09/11 PCR product. Genotyping of IL10 SNPs (rs1800871 and rs1800896) was performed by High Resolution Melt analysis. Genotyping of TNFα SNP (rs1800629) was performed by fluorogenic allele-specific probes. The distribution of TNF-308 (rs1800629) allelic (p = 0.03) and genotype (p = 0.03) frequencies and HPV-58 infection has showed a statistically significant difference between case and control groups for the assessed TNFα polymorphism. When it comes to TNFα (rs1800629) allelic and genotypic distribution and HPVs 18 and 31 infections, no statistically significant differences between case and control groups were observed for the studied TNFα polymorphism. The allelic and genotypic distribution of IL10-819 (rs1800871) and IL10-1082 (rs1800896) and HPV infection (HPVs 58, 18 and 31) has showed no statistically significant differences between case and control groups for the assessed IL10 polymorphisms. Furthermore, it was observed that haplotypes were associated with an increased cervical cancer risk in HPVs 16, 18 and 58-positive women. It was observed that women carrying the GTA and ATG haplotypes had 3.85 and 17.99-fold, respectively, increased cervical cancer susceptibility when infected by HPV-58. In women infected with HPV-16 and HPV-18, statistically significant results in women carrying the GTA and ATA haplotypes was observed. They had a 2.32 and 3.67-fold, respectively, increased cervical cancer susceptibility when infected by these two HPV types. The analysis of the haplotypes distribution in women infected with HPV-31 has showed no statistically significant results. Our study indicates that the association of genetic polymorphism in inflammation-related genes represents a risk to the susceptibility in the development of cervical cancer in women infected by HPVs 16, 18 and 58.

Novel E6 and E7 oncogenes variants of human papillomavirus type 31 in Brazilian women with abnormal cervical cytology.

HPV-31 has been widely described as an important oncogenic type, showing high incidence in worldwide and especially in Northeastern Brazil. We sought to identify the presence of specific mutations in HPV-31 E6 and E7 oncogenes in women with abnormal cervical smear. We enrolled 150 gynecological patients from Sergipe State, Northeastern Brazil. HPV screening was carried out by polymerase chain reaction (MY09/11). E6 and E7 oncogenes were amplified with specific primers and sequenced. The sequences obtained were aligned with the GenBank reference sequences in order to search for genetic variants. We identified genetic variants in E6 and E7 sequences from HPV-31. Two new nucleotide changes in E6 and E7 were described for the first time in this study. A novel mutation in E6 resulted in amino acid change in a site belonging to T-cell epitope with MHC II binding activity. There was no significant difference in the distribution of HPV-31 E6 and E7 variants when compared to all selected clinical/epidemiological characteristics. HPV-31 isolates have been clustered into three main groups called lineages A, B and C. We describe new HPV-31 variants in Brazil, contributing to better understand the genomic diversity of these viruses.