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1.
Appl Environ Microbiol ; : e0116524, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012101

RESUMO

Antibiotic resistance has emerged as a global threat to public health, generating a growing interest in investigating the presence of antibiotic-resistant bacteria in environments influenced by anthropogenic activities. Wastewater treatment plants in hospital serve as significant reservoirs of antimicrobial-resistant bacteria, where a favorable environment is established, promoting the proliferation and transfer of resistance genes among different bacterial species. In our study, we isolated a total of 243 strains from 5 hospital wastewater sites in Mexico, belonging to 21 distinct Gram-negative bacterial species. The presence of ß-lactamase was detected in 46.9% (114/243) of the isolates, which belonging to the Enterobacteriaceae family. We identified a total of 169 ß-lactamase genes; blaTEM in 33.1%, blaCTX-M in 25.4%, blaKPC in 25.4%, blaNDM 8.8%, blaSHV in 5.3%, and blaOXA-48 in 1.1% distributed in 12 different bacteria species. Among the 114 of the isolates, 50.8% were found to harbor at least one carbapenemase and were discharged into the environment. The carbapenemase blaKPC was found in six Citrobacter spp. and E. coli, while blaNDM was detected in two distinct Enterobacter spp. and E. coli. Notably, blaNDM-1 was identified in a 110 Kb IncFII conjugative plasmid in E. cloacae, E. xiangfangensis, and E. coli within the same hospital wastewater. In conclusion, hospital wastewater showed the presence of Enterobacteriaceae carrying a high frequency of carbapenemase blaKPC and blaNDM. We propose that hospital wastewater serves as reservoirs for resistance mechanism within bacterial communities and creates an optimal environment for the exchange of this resistance mechanism among different bacterial strains. IMPORTANCE: The significance of this study lies in its findings regarding the prevalence and diversity of antibiotic-resistant bacteria and genes identified in hospital wastewater in Mexico. The research underscores the urgent need for enhanced surveillance and prevention strategies to tackle the escalating challenge of antibiotic resistance, particularly evident through the elevated frequencies of carbapenemase genes such as blaKPC and blaNDM within the Enterobacteriaceae family. Moreover, the identification of these resistance genes on conjugative plasmids highlights the potential for widespread transmission via horizontal gene transfer. Understanding the mechanisms of antibiotic resistance in hospital wastewater is crucial for developing targeted interventions aimed at reducing transmission, thereby safeguarding public health and preserving the efficacy of antimicrobial therapies.

2.
Front Immunol ; 14: 1039274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776846

RESUMO

Background: The axolotl, Ambystoma mexicanum is a unique biological model for complete tissue regeneration. Is a neotenic endangered species and is highly susceptible to environmental stress, including infectious disease. In contrast to other amphibians, the axolotl is particularly vulnerable to certain viral infections. Like other salamanders, the axolotl genome is one of the largest (32 Gb) and the impact of genome size on Ig loci architecture is unknown. To better understand the immune response in axolotl, we aimed to characterize the immunoglobulin loci of A. mexicanum and compare it with other model vertebrates. Methods: The most recently published genome sequence of A. mexicanum (V6) was used for alignment-based annotation and manual curation using previously described axolotl Ig sequences or reference sequences from other vertebrates. Gene models were further curated using A. mexicanum spleen RNA-seq data. Human, Xenopus tropicalis, Danio rerio (zebrafish), and eight tetrapod reference genomes were used for comparison. Results: Canonical A. mexicanum heavy chain (IGH), lambda (IGL), sigma (IGS), and the putative surrogate light chain (SLC) loci were identified. No kappa locus was found. More than half of the IGHV genes and the IGHF gene are pseudogenes and there is no clan I IGHV genes. Although the IGH locus size is proportional to genome size, we found local size restriction in the IGHM gene and the V gene intergenic distances. In addition, there were V genes with abnormally large V-intron sizes, which correlated with loss of gene functionality. Conclusion: The A. mexicanum immunoglobulin loci share the same general genome architecture as most studied tetrapods. Consistent with its large genome, Ig loci are larger; however, local size restrictions indicate evolutionary constraints likely to be imposed by high transcriptional demand of certain Ig genes, as well as the V(D)J recombination over very long genomic distance ranges. The A. mexicanum has undergone an extensive process of Ig gene loss which partially explains a reduced potential repertoire diversity that may contribute to its impaired antibody response.


Assuntos
Ambystoma mexicanum , Imunoglobulinas , Animais , Ambystoma mexicanum/genética , Genoma , Genômica , Imunoglobulinas/genética
3.
Antibiotics (Basel) ; 11(2)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35203760

RESUMO

The use of colistin in food-producing animals favors the emergence and spread of colistin-resistant strains. Here, we investigated the occurrence and molecular mechanisms of colistin resistance among E. coli isolates from a Mexican piglet farm. A collection of 175 cephalosporin-resistant colonies from swine fecal samples were recovered. The colistin resistance phenotype was identified by rapid polymyxin test and the mcr-type genes were screened by PCR. We assessed the colistin-resistant strains by antimicrobial susceptibility test, pulse-field gel electrophoresis, plasmid profile, and mating experiments. Whole-Genome Sequencing data was used to explore the resistome, virulome, and mobilome of colistin-resistant strains. A total of four colistin-resistant E. coli were identified from the cefotaxime-resistant colonies. All harbored the plasmid-borne mcr-1 gene, which was located on conjugative 170-kb IncHI-2 plasmid co-carrying ESBLs genes. Thus, high antimicrobial resistance rates were observed for several antibiotic families. In the RC2-007 strain, the mcr-1 gene was located as part of a prophage carried on non-conjugative 100-kb-plasmid, which upon being transformed into K. variicola strain increased the polymyxin resistance 2-fold. The genomic analysis showed a broad resistome and virulome. Our findings suggest that colistin resistance followed independent acquisition pathways as clonal and non-genetically related mcr-1-harboring strains were identified. These E. coli isolates represent a reservoir of antibiotic resistance and virulence genes in animals for human consumption which could be potentially propagated into other interfaces.

4.
Curr Res Insect Sci ; 1: 100014, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36003598

RESUMO

Insect neuropeptides, play a central role in the control of many physiological processes. Based on an analysis of Nyssorhynchus albimanus brain transcriptome a neuropeptide precursor database of the mosquito was described. Also, we observed that adipokinetic hormone/corazonin-related peptide (ACP), hugin and corazonin encoding genes were differentially expressed during Plasmodium infection. Transcriptomic data from Ny. albimanus brain identified 29 pre-propeptides deduced from the sequences that allowed the prediction of at least 60 neuropeptides. The predicted peptides include isoforms of allatostatin C, orcokinin, corazonin, adipokinetic hormone (AKH), SIFamide, capa, hugin, pigment-dispersing factor, adipokinetic hormone/corazonin-related peptide (ACP), tachykinin-related peptide, trissin, neuropeptide F, diuretic hormone 31, bursicon, crustacean cardioactive peptide (CCAP), allatotropin, allatostatin A, ecdysis triggering hormone (ETH), diuretic hormone 44 (Dh44), insulin-like peptides (ILPs) and eclosion hormone (EH). The analysis of the genome of An. albimanus and the generated transcriptome, provided evidence for the identification of myosuppressin neuropeptide precursor. A quantitative analysis documented increased expression of precursors encoding ACP peptide, hugin and corazonin in the mosquito brain after Plasmodium berghei infection. This work represents an initial effort to characterize the neuropeptide precursors repertoire of Ny. albimanus and provides information for understanding neuroregulation of the mosquito response during Plasmodium infection.

5.
Viruses ; 14(1)2021 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-35062275

RESUMO

Chikungunya virus (CHIKV) is an alphavirus transmitted by Aedes mosquitoes, which causes Chikungunya fever. Three CHIKV genotypes have been identified: West African, East-Central-South African and Asian. In 2014, CHIKV was detected for the first time in Mexico, accumulating 13,569 confirmed cases in the following three years. Studies on the molecular diversification of CHIKV in Mexico focused on limited geographic regions or investigated only one structural gene of the virus. To describe the dynamics of this outbreak, we analyzed 309 serum samples from CHIKV acute clinical cases from 15 Mexican states. Partial NSP3, E1, and E2 genes were sequenced, mutations were identified, and their genetic variability was estimated. The evolutionary relationship with CHIKV sequences sampled globally were analyzed. Our sequences grouped with the Asian genotype within the Caribbean lineage, suggesting that the Asian was the only circulating genotype during the outbreak. Three non-synonymous mutations (E2 S248F and NSP3 A437T and L451F) were present in our sequences, which were also identified in sequences of the Caribbean lineage and in one Philippine sequence. Based on the phylogeographic analysis, the viral spread was reconstructed, suggesting that after the introduction through the Mexican southern border (Chiapas), CHIKV dispersed to neighboring states before reaching the center and north of the country through the Pacific Ocean states and Quintana Roo. This is the first viral phylogeographic reconstruction in Mexico characterizing the CHIKV outbreak across the country.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Variação Genética , Epidemiologia Molecular , Aedes/virologia , Animais , Região do Caribe , Febre de Chikungunya/epidemiologia , Surtos de Doenças , Genótipo , México/epidemiologia , Mutação , Oceano Pacífico , Filogenia , Filogeografia
6.
Mol Biochem Parasitol ; 240: 111337, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33147473

RESUMO

The heat shock protein family 70 (Hsp70) comprises chaperone proteins that play major multiple roles in Plasmodium asexual and sexual development. In this study, we analyzed the expression of Hsp70-1 in gametocytes, gametes, zygotes, and its participation in ookinete formation and their transition into oocysts. A monoclonal antibody against recombinant Hsp70-1 revealed its presence in zygotes and micronemes of ookinetes. Compared to wild type parasites, Hsp70-1 knockout ookinetes produced fewer oocysts in Plasmodium-susceptible Anopheles albimanus mosquitoes. This may indicate a defective transformation of ookinetes into oocysts in the absence of Hsp70-1. The presence of this protein in micronemes suggests its participation in mosquito infection, probably aiding to the adequate structural conformation of proteins in charge of motility, recognition and invasion of the insect midgut epithelium.


Assuntos
Anopheles/parasitologia , Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Plasmodium berghei/genética , Proteínas de Protozoários/genética , Animais , Trato Gastrointestinal/parasitologia , Vetores Genéticos/genética , Estágios do Ciclo de Vida , Masculino , Fenótipo , Plasmodium berghei/crescimento & desenvolvimento , Ratos , Zigoto/metabolismo
7.
Braz J Microbiol ; 51(4): 2009-2014, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32897511

RESUMO

Using molecular and whole-genome sequencing tools, we investigated colistin-resistant Escherichia coli isolates from wild sea lions. Two unrelated E. coli colistin-resistant isolates, ST8259 and ST4218, were identified, both belonging to the B2 phylogroup and different serotypes. Polymorphisms in PmrA, PmrB, and PhoQ proteins were identified, and the role of PmrB and PhoQ in contributing to colistin resistance was determined by complementation assays. However, the mutations characterized in the present study are not involved in colistin resistance, which have been described in E. coli isolates from clinical settings. Therefore, the acquired mutations in pmrB and phoQ genes in resistance to colistin in bacteria related to marine environment animals are different. This work contributes to the surveillance and characterization of colistin resistance in Escherichia coli obtained from animals from aquatic environments.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Escherichia coli/classificação , Escherichia coli/efeitos dos fármacos , Genoma Bacteriano , Leões-Marinhos/microbiologia , Animais , Animais Selvagens/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Proteínas de Escherichia coli/genética , Testes de Sensibilidade Microbiana , Sorogrupo , Sequenciamento Completo do Genoma
8.
Front Immunol ; 11: 736, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435242

RESUMO

The origin and function of blood IgM+IgD+CD27+ B cells is controversial, and they are considered a heterogeneous population. Previous staining of circulating B cells of healthy donors with rotavirus fluorescent virus-like particles allowed us to differentiate two subsets of IgM+IgD+CD27+: IgMhi and IgMlo B cells. Here, we confirmed this finding and compared the phenotype, transcriptome, in vitro function, and Ig gene repertoire of these two subsets. Eleven markers phenotypically discriminated both subsets (CD1c, CD69, IL21R, CD27, MTG, CD45RB, CD5, CD184, CD23, BAFFR, and CD38) with the IgMhi phenotypically resembling previously reported marginal zone B cells and the IgMlo resembling both naïve and memory B cells. Transcriptomic analysis showed that both subpopulations clustered close to germinal center-experienced IgM only B cells with a Principal Component Analysis, but differed in expression of 78 genes. Moreover, IgMhi B cells expressed genes characteristic of previously reported marginal zone B cells. After stimulation with CpG and cytokines, significantly (p < 0.05) higher frequencies (62.5%) of IgMhi B cells proliferated, compared with IgMlo B cells (35.37%), and differentiated to antibody secreting cells (14.22% for IgMhi and 7.19% for IgMlo). IgMhi B cells had significantly (p < 0.0007) higher frequencies of mutations in IGHV and IGKV regions, IgMlo B cells had higher usage of IGHJ6 genes (p < 0.0001), and both subsets differed in their HCDR3 properties. IgMhi B cells shared most of their shared IGH clonotypes with IgM only memory B cells, and IgMlo B cells with IgMhi B cells. These results support the notion that differential expression of IgM and IgD discriminates two subpopulations of human circulating IgM+IgD+CD27+ B cells, with the IgMhi B cells having similarities with previously described marginal zone B cells that passed through germinal centers, and the IgMlo B cells being the least differentiated amongst the IgM+CD27+ subsets.


Assuntos
Subpopulações de Linfócitos B/fisiologia , Linfócitos B/imunologia , Centro Germinativo/imunologia , Imunoglobulina D/metabolismo , Imunoglobulina M/metabolismo , Adulto , Perfilação da Expressão Gênica , Humanos , Imunoglobulina D/genética , Cadeias Pesadas de Imunoglobulinas/genética , Imunoglobulina M/genética , Região Variável de Imunoglobulina/genética , Imunofenotipagem , Fenótipo , Análise de Componente Principal , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
9.
J Chemother ; 31(6): 349-353, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31046636

RESUMO

Carbapenem-resistant Gram-negative bacteria isolated in Venezuela have been poorly characterized. The present study characterized a total of 34 isolates obtained from 27 patients; five of these patients were multi-infected. The bacterial species identified were Klebsiella pneumoniae (17), Pseudomonas aeruginosa (9), and Acinetobacter baumannii (8). From these isolates, 85% were identified as carbapenemase-producing bacteria, and the identified carbapenemase genes were blaKPC-2 (10/29 [34.4%]), blaVIM-type (7/29 [24.1%]), blaOXA-23 (7/29 [24.1%]), blaNDM-1 (8/29 [27.5%]), and the coexistence of blaOXA-23/blaNDM-1 (2/29 [6.8%]). Patient 1 was multi-infected by K. pneumoniae ST11 and ST2413 isolates harbouring the blaNDM-1 and blaKPC-2 genes, respectively. The other patients were multi-infected by two or three different bacterial species such as ESBL-producing K. pneumoniae isolates, P. aeruginosa harbouring the blaVIM-type gene, K. pneumoniae ST147 harbouring the blaKPC-2 gene and by A. baumannii harbouring the blaOXA-23 gene. The blaNDM-1 gene in A. baumannii is flanked by an uncommon genetic structure, whereas blaNDM-1 gene in K. pneumoniae revealed a common structure described in different plasmids from Enterobacteriaceae isolates. This study provides new information about the epidemiology of carbapenemase-producing bacteria in clinical setting in Venezuela.


Assuntos
Proteínas de Bactérias/biossíntese , Bactérias Gram-Negativas/genética , Resistência beta-Lactâmica/genética , beta-Lactamases/biossíntese , Acinetobacter baumannii , Adulto , Feminino , Genes Bacterianos/genética , Bactérias Gram-Negativas/enzimologia , Humanos , Klebsiella pneumoniae , Masculino , Pessoa de Meia-Idade , Pseudomonas aeruginosa , Venezuela
10.
Front Immunol ; 9: 2679, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519242

RESUMO

Antibody class switch recombination (CSR) to IgG, IgA, or IgE is a hallmark of adaptive immunity, allowing antibody function diversification beyond IgM. CSR involves a deletion of the IgM/IgD constant region genes placing a new acceptor Constant gene, downstream of the VDJH exon. CSR depends on non-coding (CSRnc) transcription of donor Iµ and acceptor IH exons, located 5' upstream of each CH coding gene. Although, our knowledge of the role of CSRnc transcription has advanced greatly, its extension and importance in healthy and diseased humans is scarce. We analyzed CSRnc transcription in 70,603 publicly available RNA-seq samples, including GTEx, TCGA, and the Sequence Read Archive using recount2, an online resource consisting of normalized RNA-seq gene and exon counts, as well as, coverage BigWig files that can be programmatically accessed through R. CSRnc transcription was validated with a qRT-PCR assay for Iµ, Iγ3, and Iγ1 in humans in response to vaccination. We mapped IH transcription for the human IGH locus, including the less understood IGHD gene. CSRnc transcription was restricted to B cells and is widely distributed in normal adult tissues, but predominant in blood, spleen, MALT-containing tissues, visceral adipose tissue and some so-called "immune privileged" tissues. However, significant Iγ4 expression was found even in non-lymphoid fetal tissues. CSRnc expression in cancer tissues mimicked the expression of their normal counterparts, with notable pattern changes in some common cancer subsets. CSRnc transcription in tumors appears to result from tumor infiltration by B cells, since CSRnc transcription was not detected in corresponding tumor-derived immortal cell lines. Additionally, significantly increased Iδ transcription in ileal mucosa in Crohn's disease with ulceration was found. In conclusion, CSRnc transcription occurs in multiple anatomical locations beyond classical secondary lymphoid organs, representing a potentially useful marker of effector B cell responses in normal and pathological immune responses. The pattern of IH exon expression may reveal clues of the local immune response (i.e., cytokine milieu) in health and disease. This is a great example of how the public recount2 data can be used to further our understanding of transcription, including regions outside the known transcriptome.


Assuntos
Linfócitos B/imunologia , Genes de Cadeia Pesada de Imunoglobulina/imunologia , Switching de Imunoglobulina/imunologia , Transcrição Gênica/imunologia , Éxons VDJ/imunologia , Adulto , Linfócitos B/patologia , Linhagem Celular Transformada , Bases de Dados de Ácidos Nucleicos , Feminino , Humanos , Masculino , Neoplasias/imunologia
11.
BMC Genomics ; 19(1): 296, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29699489

RESUMO

BACKGROUND: Chagas disease is a parasitic infection caused by Trypanosoma cruzi. It is an important public health problem affecting around seven to eight million people in the Americas. A large number of hematophagous triatomine insect species, occupying diverse natural and human-modified ecological niches transmit this disease. Triatomines are long-living hemipterans that have evolved to explode different habitats to associate with their vertebrate hosts. Understanding the molecular basis of the extreme physiological conditions including starvation tolerance and longevity could provide insights for developing novel control strategies. We describe the normalized cDNA, full body transcriptome analysis of three main vectors in North, Central and South America, Triatoma pallidipennis, T. dimidiata and T. infestans. RESULTS: Two-thirds of the de novo assembled transcriptomes map to the Rhodnius prolixus genome and proteome. A Triatoma expansion of the calycin family and two types of protease inhibitors, pacifastins and cystatins were identified. A high number of transcriptionally active class I transposable elements was documented in T. infestans, compared with T. dimidiata and T. pallidipennis. Sequence identity in Triatoma-R. prolixus 1:1 orthologs revealed high sequence divergence in four enzymes participating in gluconeogenesis, glycogen synthesis and the pentose phosphate pathway, indicating high evolutionary rates of these genes. Also, molecular evidence suggesting positive selection was found for several genes of the oxidative phosphorylation I, III and V complexes. CONCLUSIONS: Protease inhibitors and calycin-coding gene expansions provide insights into rapidly evolving processes of protease regulation and haematophagy. Higher evolutionary rates in enzymes that exert metabolic flux control towards anabolism and evidence for positive selection in oxidative phosphorylation complexes might represent genetic adaptations, possibly related to prolonged starvation, oxidative stress tolerance, longevity, and hematophagy and flight reduction. Overall, this work generated novel hypothesis related to biological adaptations to extreme physiological conditions and diverse ecological niches that sustain Chagas disease transmission.


Assuntos
Doença de Chagas/parasitologia , Metabolismo Energético , Genômica , Insetos Vetores/genética , Transcriptoma , Triatoma/genética , Adaptação Fisiológica , Animais , Evolução Biológica , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Ecologia , Genoma de Inseto , Insetos Vetores/classificação , Insetos Vetores/metabolismo , Insetos Vetores/parasitologia , Família Multigênica , América do Sul , Triatoma/classificação , Triatoma/metabolismo , Triatoma/parasitologia
12.
Front Immunol ; 8: 176, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28303135

RESUMO

Innate lymphoid cells (ILC) are members of a heterogeneous family with a lymphoid origin that mimics the T helper (Th) cytokine profile. ILC are involved in early effector cytokine-mediated responses during infections in peripheral tissues. ILC also play an important role in chronic skin inflammatory diseases, including psoriasis. Although classical ILC express CD127, it has been recently reported that the presence of non-classical CD127- ILC populations and an early ILC precursor (EILP) CD127low. ILC development has predominately been investigated in mouse models. However, in humans, different transcription factors have been described for ILC identification. NFIL3 (nuclear factor, IL-3 regulated) is crucial for ILC development in response to IL-7. CD123 (IL-3Rα) is usually used to exclude basophils during ILC identification, however, it is unknown if in response to IL-3, NFIL3 could be relevant to induce ILC features in Lin- CD123+ populations in addition, is also unknown whether peripheral blood (PB) population with ILC features may have skin-homing potential to participate in skin inflammatory chronic diseases. Here, we report a Lin- CD123+ CD127low CD7+ CLA+ population that share some phenotypic properties with basophils, but expresses several transcription factors for ILC commitment such as inhibitor of DNA binding 2 (Id2), NFIL3, promyelocytic leukemia zinc finger (PLZF), thymocyte selection-associated high-mobility group box protein (TOX), and T cell factor-1 (TCF-1). In addition, this population expresses different ILC markers: CD132, CD90, CD161, α4 integrin, c-Kit, CRTH2, AhR, and IL-23R. IL-3 prevents apoptosis and increases their NFIL3, TOX, and PLZF expression. In PB, the CD123+ CD127low population is predominantly a conspicuous population that expresses T-bet and RORγt. The Lin- CD123+ CD127low population in PB has a limited Th type cytokine expression and highly expresses IL-8. The Lin- CD123+ CD127low population expresses skin-homing receptors (cutaneous lymphocyte antigen and CXCR4) and transmigrates through endothelial cells in response to SDF-1. An equivalent Lin- CD123low population was identified in control skin, which shows a broader phenotypic diversity and cytokine production, including IL-22 and IL-17. Remarkably, the CD123low population in the lesion and non-lesion skin of psoriasis patients expresses IL-17 and IL-22. Our findings suggest the identification of an alternative Lin- CD123+ CD127low population with ILC features endowed with migratory capabilities that might contribute to immunopathological hallmarks of psoriasis.

13.
Biochem Cell Biol ; 95(2): 310-317, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28177775

RESUMO

For malaria transmission, Plasmodium parasites must develop in the mosquito vector. Oxidative stress in the insect midgut, triggered by environmental changes (e.g., pH and temperature), influences the cellular signaling involved in differentiation from gametocytes to mobile ookinetes for the purpose of parasite survival. Oxidative stress activates the homeostatic response to stress characterized by the phosphorylation eIF2α, the attenuation of protein synthesis, and the transcription of genes participating in the unfolded protein response and antioxidant processes, forming a part of an integrated stress response (ISR). We hypothesized that ISR operates during the differentiation of gametocytes to ookinetes to assure Plasmodium survival. Using in-vitro conditions resembling the mosquito midgut conditions, we cultured Plasmodium berghei gametocytes to ookinetes and evaluated the redox balance by detecting reactive oxygen species and superoxide dismutase activity. Additionally, we evaluated the phosphorylation of eIF2α, the attenuation of the global protein synthesis, and the gene expression of cellular stress markers (e.g., endoplasmic reticulum chaperones and antioxidant molecules, measured by reverse-transcription quantitative polymerase chain reaction), finding that these processes were all taking place, probably to improve survival during the differentiation of Plasmodium berghei ookinetes.


Assuntos
Eritrócitos/parasitologia , Fator de Iniciação 2 em Eucariotos/genética , Estágios do Ciclo de Vida/genética , Plasmodium berghei/genética , Proteínas de Protozoários/genética , Espécies Reativas de Oxigênio/metabolismo , Animais , Diferenciação Celular , Chaperona BiP do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Interações Hospedeiro-Parasita , Malária/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Biológicos , Estresse Oxidativo , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Fosforilação , Plasmodium berghei/crescimento & desenvolvimento , Plasmodium berghei/metabolismo , Cultura Primária de Células , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Proteínas de Protozoários/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Resposta a Proteínas não Dobradas
14.
PLoS One ; 11(4): e0153274, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27115350

RESUMO

Cervical cancer (CC) is caused by high-risk human papillomavirus persistence due to the immunosuppressive tumor microenvironment mediated by cytokines. Vaginal microbiota determines the presence of certain cytokines locally. We assessed the association between cervical microbiota diversity and the histopathological diagnosis of each stage of CC, and we evaluated mRNA cervical expression levels of IL-4, IL-6, IL-10, TGF-ß1, TNF-α and IFN-γ across the histopathological diagnosis and specific bacterial clusters. We determined the cervical microbiota by high throughput sequencing of 16S rDNA amplicons and classified it in community state types (CST). Mean difference analyses between alpha-diversity and histopathological diagnosis were carried out, as well as a ß-diversity analysis within the histological diagnosis. Cervical cytokine mRNA expression was analyzed across the CSTs and the histopathological diagnoses. We found a significant difference in microbiota's diversity in NCL-HPV negative women vs those with squamous intraepithelial lesions (SIL) and CC(p = 0.006, p = 0.036).When ß-diversity was evaluated, the CC samples showed the highest variation within groups (p<0.0006) and the largest distance compared to NCL-HPV negative ones (p<0.00001). The predominant bacteria in women with normal cytology were L. crispatus and L. iners, whereas for SIL, it was Sneathia spp. and for CC, Fusobacterium spp. We found higher median cervical levels of IL-4 and TGF-ß1 mRNA in the CST dominated by Fusobacterium spp. These results suggest that the cervical microbiota may be implicated in cervical cancer pathology. Further cohort studies are needed to validate these findings.


Assuntos
Citocinas/genética , Microbiota , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/microbiologia , Adulto , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/microbiologia , Carcinoma de Células Escamosas/patologia , Estudos Transversais , Feminino , Humanos , Interferon gama/genética , Interleucina-10/genética , Interleucina-4/genética , Interleucina-6/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , RNA Mensageiro/genética , RNA Neoplásico/genética , Lesões Intraepiteliais Escamosas Cervicais/imunologia , Lesões Intraepiteliais Escamosas Cervicais/microbiologia , Lesões Intraepiteliais Escamosas Cervicais/patologia , Transcriptoma , Fator de Crescimento Transformador beta1/genética , Fator de Necrose Tumoral alfa/genética , Neoplasias do Colo do Útero/patologia
16.
Genome Med ; 8(1): 23, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26917418

RESUMO

BACKGROUND: The study of human B cell response to dengue virus (DENV) infection is critical to understand serotype-specific protection and the cross-reactive sub-neutralizing response. Whereas the first is beneficial and thus represents the ultimate goal of vaccination, the latter has been implicated in the development of severe disease, which occurs in a small, albeit significant, fraction of secondary DENV infections. Both primary and secondary infections are associated with the production of poly-reactive and cross-reactive IgG antibodies. METHODS: To gain insight into the effect of DENV infection on the B cell repertoire, we used VH region high-throughput cDNA sequencing of the peripheral blood IgG B cell compartment of 19 individuals during the acute phase of infection. For 11 individuals, a second sample obtained 6 months later was analyzed for comparison. Probabilities of sequencing antibody secreting cells or memory B cells were estimated using second-order Monte Carlo simulation. RESULTS: We found that in acute disease there is an increase in IgG B cell diversity and changes in the relative use of segments IGHV1-2, IGHV1-18, and IGHV1-69. Somewhat unexpectedly, an overall low proportion of somatic hypermutated antibody genes was observed during the acute phase plasmablasts, particularly in secondary infections and those cases with more severe disease. CONCLUSIONS: Our data are consistent with an innate-like antiviral recognition system mediated by B cells using defined germ-line coded B cell receptors, which could provide a rapid germinal center-independent antibody response during the early phase of infection. A model describing concurrent T-dependent and T-independent B cell responses in the context of DENV infection is proposed, which incorporates the selection of B cells using hypomutated IGHV segments and their potential role in poly/cross-reactivity. Its formal demonstration could lead to a definition of its potential implication in antibody-dependent enhancement, and may contribute to rational vaccine development efforts.


Assuntos
Linfócitos B/imunologia , Linfócitos B/metabolismo , Vírus da Dengue/imunologia , Dengue/genética , Dengue/imunologia , Centro Germinativo/imunologia , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Hipermutação Somática de Imunoglobulina , Doença Aguda , Adolescente , Adulto , Motivos de Aminoácidos , Análise por Conglomerados , Regiões Determinantes de Complementaridade/genética , Biologia Computacional , Dengue/diagnóstico , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/genética , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Masculino , Pessoa de Meia-Idade , Mutação , Matrizes de Pontuação de Posição Específica , Sorogrupo , Adulto Jovem
17.
Genome Med ; 7: 124, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26608341

RESUMO

BACKGROUND: Despite the potential to produce antibodies that can neutralize different virus (heterotypic neutralization), there is no knowledge of why vaccination against influenza induces protection predominantly against the utilized viral strains (homotypic response). Identification of structural patterns of the B cell repertoire associated to heterotypic neutralization may contribute to identify relevant epitopes for a universal vaccine against influenza. METHODS: Blood samples were collected from volunteers immunized with 2008/2009 trivalent inactivated vaccine (TIV), pandemic H1N1 (pdmH1N1) monovalent inactivated vaccine (MIV) and the 2014/2015 TIV. Neutralization was assessed by hemagglutination and microneutralization test. IgG V(H) amplicons derived from peripheral blood RNA from pre-immune and 7 days post vaccination were subjected to 454-Roche sequencing. Full reconstruction of the sampled repertoires was done with ImmunediveRsity. RESULTS: The TIV induced a predominantly homotypic neutralizing serologic response, while the 09 MIV induced a heterotypic neutralizing seroconversion in 17% of the individuals. Both the 08/09 and the 14/15 TIV were associated with a reduction in clonotypic diversity, whereas 09 MIV was the opposite. Moreover, TIV and MIV induced distinctive patterns of IGHV segment use that are consistent with B cell selection by conserved antigenic determinants shared by the pre-pandemic and the pandemic strains. However, low somatic hypermutation rates in IgG after 09 MIV immunization, but not after 08/09 and 14/15 TIV immunization were observed. Furthermore, no evidence of the original antigenic sin was found in the same individuals after vaccination with the three vaccines. CONCLUSIONS: Immunization with a new influenza virus strain (2009 pdmH1N1) induced unique effects in the peripheral B cell repertoire clonal structure, a stereotyped response involving distinctive IGHV segment use and low somatic hypermutation levels. These parameters were contrastingly different to those observed in response to pre-pandemic and post-pandemic vaccination, and may be the result of clonal selection of common antigenic determinants, as well as germinal center-independent responses that wane as the pandemic strain becomes seasonal. Our findings may contribute in the understanding of the structural and cellular basis required to develop a universal influenza vaccine.


Assuntos
Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Adulto , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/genética , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Epitopos de Linfócito B/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/efeitos adversos , Influenza Humana/sangue , Influenza Humana/genética , Influenza Humana/prevenção & controle , Estudos Longitudinais , RNA/sangue , RNA/genética , Análise de Sequência de DNA , Hipermutação Somática de Imunoglobulina , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia
18.
Genome Announc ; 3(5)2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26358599

RESUMO

Three endophytic Klebsiella variicola isolates-T29A, 3, and 6A2, obtained from sugar cane stem, maize shoots, and banana leaves, respectively-were used for whole-genome sequencing. Here, we report the draft genome sequences of circular chromosomes and plasmids. The genomes contain plant colonization and cellulases genes. This study will help toward understanding the genomic basis of K. variicola interaction with plant hosts.

19.
MAbs ; 7(3): 516-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25875140

RESUMO

The B cell antigen receptor repertoire is highly diverse and constantly modified by clonal selection. High-throughput DNA sequencing (HTS) of the lymphocyte repertoire (Rep-Seq) represents a promising technology to explore such diversity ex-vivo and assist in the identification of antigen-specific antibodies based on molecular signatures of clonal selection. Therefore, integrative tools for repertoire reconstruction and analysis from antibody sequences are needed. We developed ImmunediveRity, a stand-alone pipeline primarily based in R programming for the integral analysis of B cell repertoire data generated by HTS. The pipeline integrates GNU software and in house scripts to perform quality filtering, sequencing noise correction and repertoire reconstruction based on V, D and J segment assignment, clonal origin and unique heavy chain identification. Post-analysis scripts generate a wealth of repertoire metrics that in conjunction with a rich graphical output facilitates sample comparison and repertoire mining. Its performance was tested with raw and curated human and mouse 454-Roche sequencing benchmarks providing good approximations of repertoire structure. Furthermore, ImmunediveRsity was used to mine the B cell repertoire of immunized mice with a model antigen, allowing the identification of previously validated antigen-specific antibodies, and revealing different and unexpected clonal diversity patterns in the post-immunization IgM and IgG compartments. Although ImmunediveRsity is similar to other recently developed tools, it offers significant advantages that facilitate repertoire analysis and repertoire mining. ImmunediveRsity is open source and free for academic purposes and it runs on 64 bit GNU/Linux and MacOS. Available at: https://bitbucket.org/ImmunediveRsity/immunediversity/.


Assuntos
Anticorpos Monoclonais/genética , Especificidade de Anticorpos/genética , Receptores de Antígenos de Linfócitos B/genética , Análise de Sequência de DNA/métodos , Software , Animais , Anticorpos Monoclonais/imunologia , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Imunoglobulina M/genética , Imunoglobulina M/imunologia , Camundongos , Receptores de Antígenos de Linfócitos B/imunologia
20.
BMC Microbiol ; 15: 64, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25886267

RESUMO

BACKGROUND: Klebsiella variicola was very recently described as a new bacterial species and is very closely related to Klebsiella pneumoniae; in fact, K. variicola isolates were first identified as K. pneumoniae. Therefore, it might be the case that some isolates, which were initially classified as K. pneumoniae, are actually K. variicola. The aim of this study was to devise a multiplex-PCR probe that can differentiate isolates from these sister species. RESULT: This work describes the development of a multiplex-PCR method to identify K. variicola. This development was based on sequencing a K. variicola clinical isolate (801) and comparing it to other K. variicola and K. pneumoniae genomes. The phylogenetic analysis showed that K. variicola isolates form a monophyletic group that is well differentiated from K. pneumoniae. Notably, the isolate K. pneumoniae 342 and K. pneumoniae KP5-1 might have been misclassified because in our analysis, both clustered with K. variicola isolates rather than with K. pneumoniae. The multiplex-PCR (M-PCR-1 to 3) probe system could identify K. variicola with high accuracy using the shared unique genes of K. variicola and K. pneumoniae genomes, respectively. M-PCR-1 was used to assay a collection of multidrug-resistant (503) and antimicrobial-sensitive (557) K. pneumoniae clinical isolates. We found K. variicola with a prevalence of 2.1% (23/1,060), of them a 56.5% (13/23) of the isolates were multidrug resistant, and 43.5% (10/23) of the isolates were antimicrobial sensitive. The phylogenetic analysis of rpoB of K. variicola-positive isolates identified by multiplex-PCR support the correct identification and differentiation of K. variicola from K. pneumoniae clinical isolates. CONCLUSIONS: This multiplex-PCR provides the means to reliably identify and genotype K. variicola. This tool could be very helpful for clinical, epidemiological, and population genetics studies of this species. A low but significant prevalence of K. variicola isolates was found, implying that misclassification had occurred previously. We believe that our multiplex-PCR assay could be of paramount importance to understand the population dynamics of K. variicola in both clinical and environmental settings.


Assuntos
Técnicas Bacteriológicas/métodos , Infecções por Klebsiella/diagnóstico , Klebsiella/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Antibacterianos/farmacologia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana Múltipla , Humanos , Recém-Nascido , Klebsiella/genética , Infecções por Klebsiella/microbiologia , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência
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