RESUMO
Pseudomonas spp., such as P. fluorescens group, P. fragi, and P. putida, are the major psychrophilic spoilage bacteria in the food industry. Bacteriophages (phages) are a promising tool for controlling food-spoilage and food-poisoning bacteria; however, there are few reports on phages effective on food-spoilage bacteria such as Pseudomonas spp. In this study, 12 Pseudomonas phages were isolated from chicken and soil samples. Based on the host range and lytic activity at 30 °C and 4 °C and various combinations of phages, phages vB_PflP-PCS4 and vB_PflP-PCW2 were selected to prepare phage cocktails to control Pseudomonas spp. The phage cocktail consisting of vB_PflP-PCS4 and vB_PflP-PCW2 showed the strongest lytic activity and retarded regrowth of P. fluorescens and P. putida at 30 °C, 8 °C, and 4 °C at a multiplicity of infection of 100. Nucleotide sequence analysis of the genomic DNA indicated that vB_PflP-PCS4 and vB_PflP-PCW2 phages were lytic phages of the Podoviridae family and lacked tRNA, toxin, or virulence genes. A novel endolysin gene was found in the genomic DNA of phage vB_PflP-PCS4. The results of this study suggest that the phage cocktail consisting of vB_PflP-PCS4 and vB_PflP-PCW2 is a promising tool for the biocontrol of psychrophilic food-spoilage pseudomonads during cold storage and distribution.
Assuntos
Galinhas , Microbiologia de Alimentos , Especificidade de Hospedeiro , Animais , Microbiologia do Solo , Fagos de Pseudomonas/fisiologia , Fagos de Pseudomonas/genética , Pseudomonas/virologia , Genoma Viral , Podoviridae/fisiologia , Podoviridae/genética , Podoviridae/isolamento & purificação , Podoviridae/classificação , Agentes de Controle Biológico , DNA Viral/genética , Bacteriófagos/fisiologia , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Bacteriófagos/classificaçãoRESUMO
Condom education, an important part of comprehensive sexuality education, involves lessons on negotiating, motivating and demonstrating condom use. Expanding condom-related knowledge and skill reduces risks of unwanted pregnancy, HIV and sexually transmitted infections. Condom education for adolescents has been a controversial subject among parents, teachers, health professionals and the general public. Mothers are key stakeholders in efforts to implement such programmes. Therefore, this study explored factors associated with their attitudes towards the condom education for children aged 12-14 years. We used secondary data from the Myanmar Demographic and Health Survey. The sample includes mothers (N = 7011) who had at least one living child and responded to the question "Should children aged 12-14 be taught about condom use to prevent AIDS?" The answers yes, no and unsure were used as proxy for their attitudes. In total, 41.5% of the mothers agreed with the condom education. Mothers, who had an adolescent child, belonged to an ethnic minority, rural residents, low-educated, poor knowledge of HIV and condoms were less supportive of the condom education. These findings highlight the need for rural mothers in Myanmar to be given awareness about adolescent sexual and reproductive health focusing on HIV/AIDS and condom desensitization.
Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Adolescente , Criança , Preservativos , Etnicidade , Feminino , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Grupos Minoritários , Mianmar , Gravidez , Comportamento SexualRESUMO
BACKGROUND: Recessive dystrophic epidermolysis bullosa (RDEB) is a hereditary blistering disorder due to a lack of type VII collagen. At present, treatment is mainly supportive. OBJECTIVES: To determine whether intravenous allogeneic bone marrow-derived mesenchymal stromal/stem cells (BM-MSCs) are safe in RDEB adults and if the cells improve wound healing and quality of life. METHODS: We conducted a prospective, phase I/II, open-label study recruiting 10 RDEB adults to receive 2 intravenous infusions of BM-MSCs (on day 0 and day 14; each dose 2-4 × 106 cells/kg). RESULTS: BM-MSCs were well tolerated with no serious adverse events to 12 months. Regarding efficacy, there was a transient reduction in disease activity scores (8/10 subjects) and a significant reduction in itch. One individual showed a transient increase in type VII collagen. LIMITATIONS: Open-label trial with no placebo. CONCLUSIONS: MSC infusion is safe in RDEB adults and can have clinical benefits for at least 2 months.
Assuntos
Epidermólise Bolhosa Distrófica/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Prurido/terapia , Adolescente , Adulto , Idoso , Epidermólise Bolhosa Distrófica/complicações , Epidermólise Bolhosa Distrófica/diagnóstico , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prurido/diagnóstico , Prurido/etiologia , Qualidade de Vida , Índice de Gravidade de Doença , Transplante Homólogo/métodos , Resultado do Tratamento , Cicatrização , Adulto JovemRESUMO
Epidermal DNA damage, especially to the basal layer, is an established cause of keratinocyte cancers (KCs). Large differences in KC incidence (20- to 60-fold) between white and black populations are largely attributable to epidermal melanin photoprotection in the latter. The cyclobutane pyrimidine dimer (CPD) is the most mutagenic DNA photolesion; however, most studies suggest that melanin photoprotection against CPD is modest and cannot explain the considerable skin color-based differences in KC incidence. Along with melanin quantity, solar-simulated radiation-induced CPD assessed immediately postexposure in the overall epidermis and within 3 epidermal zones was compared in black West Africans and fair Europeans. Melanin in black skin protected against CPD by 8.0-fold in the overall epidermis and by 59.0-, 16.5-, and 5.0-fold in the basal, middle, and upper epidermis, respectively. Protection was related to the distribution of melanin, which was most concentrated in the basal layer of black skin. These results may explain, at least in part, the considerable skin color differences in KC incidence. These data suggest that a DNA protection factor of at least 60 is necessary in sunscreens to reduce white skin KC incidence to a level that is comparable with that of black skin.-Fajuyigbe, D., Lwin, S. M., Diffey, B. L., Baker, R., Tobin, D. J., Sarkany, R. P. E., Young, A. R. Melanin distribution in human epidermis affords localized protection against DNA photodamage and concurs with skin cancer incidence difference in extreme phototypes.
Assuntos
Dano ao DNA , Epiderme/efeitos da radiação , Melaninas/metabolismo , Dímeros de Pirimidina/efeitos da radiação , Neoplasias Cutâneas/epidemiologia , Pigmentação da Pele , Adulto , População Negra , Epiderme/metabolismo , Humanos , Melaninas/genética , Neoplasias Cutâneas/etnologia , Neoplasias Cutâneas/genética , Luz Solar/efeitos adversos , População BrancaRESUMO
This study focused on the isolation and characterization of bacteriophages with specific activity against toxin-producing and multidrug-resistant strains of Bacillus cereus sensu stricto (B. cereus s. s.). Ten different samples yielded six bacteriophages by utilizing the double-layer agar technique. The most promising phage, vB_BceS-M2, was selected based on its broad host range and robust lytic activity against various B. cereus s. s. strains. The phage vB_BceS-M2 had a circular double-stranded DNA genome of 56,482 bp. This phage exhibited stability over a wide range of temperatures and pH values, which is crucial for its potential application in food matrices. The combined effect of phage vB_BceS-M2 and nisin, a widely used antimicrobial peptide, was investigated to enhance antimicrobial efficacy against B. cereus in food. The results suggested that nisin showed synergy and combined effect with the phage, potentially overcoming the growth of phage-resistant bacteria in the broth. Furthermore, practical applications were conducted in various liquid and solid food matrices, including whole and skimmed milk, boiled rice, cheese, and frozen meatballs, both at 4 and 25 °C. Phage vB_BceS-M2, either alone or in combination with nisin, reduced the growth rate of B. cereus in foods other than whole milk. The combination of bacteriophage and nisin showed promise for the development of effective antimicrobial interventions to counteract toxigenic and antibiotic-resistant B. cereus in food.
Assuntos
Antibacterianos , Bacillus cereus , Farmacorresistência Bacteriana Múltipla , Microbiologia de Alimentos , Nisina , Antibacterianos/farmacologia , Bacillus cereus/virologia , Bacillus cereus/efeitos dos fármacos , Fagos Bacilares/genética , Bacteriófagos , Queijo/microbiologia , Concentração de Íons de Hidrogênio , Leite/microbiologia , Nisina/farmacologia , Oryza/microbiologia , TemperaturaRESUMO
Nowadays, the discovery of alternative natural antimicrobial substances such as bacteriophages, essential oils, and other physical and chemical agents is developing in the food industry. In this study, nine bacteriophages were isolated from various parts of raw chickens and exhibited lytic activities against L. monocytogenes and various Listeria spp. The characterization of phage vB_LmoS-PLM9 was stable at 4 to 50 °C and pH range from 4 to 10. Phage vB_LmoS-PLM9 had a circular, double-stranded genomic DNA with 38,345 bp having endolysin but no antibiotic resistance or virulence genes. Among the eight essential oils tested at 10 %, cinnamon bark, and cassia oils showed the strongest antilisterial activities. The combined use of phage vB_LmoS-PLM9 and cinnamon oils indicated higher efficiency than single treatments. The combination of phage (MOI of 10) and both cinnamon oils (0.03 %) reduced the viable counts of L. monocytogenes and inhibited the regrowth of resistant cell populations in broth at 30 °C. Furthermore, treatment with the combination of phage (MOI of 100) and cinnamon oil (0.125 %) was effective in milk, especially at 4 °C by reducing the viable count to less than lower limit of detection. These results suggest combining phage and cinnamon oil is a potential approach for controlling L. monocytogenes in milk.
Assuntos
Bacteriófagos , Cinnamomum zeylanicum , Listeria monocytogenes , Leite , Óleos Voláteis , Salmão , Animais , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/virologia , Leite/microbiologia , Cinnamomum zeylanicum/química , Óleos Voláteis/farmacologia , Salmão/microbiologia , Microbiologia de Alimentos , Óleos de Plantas/farmacologia , Conservação de Alimentos/métodos , Galinhas , Antibacterianos/farmacologiaRESUMO
Bacillus cereus sensu stricto is a foodborne pathogen that causes food poisoning. Their spore and biofilm-forming abilities persist in various environments and foods. This study investigated the prevalence, virulence, antibiotic resistance, and genetic diversity of B. cereus s. s. strains isolated from various food samples. Of 179 samples, 22.34% were positive for B. cereus s. s., with significantly high detection rates in milk products and raw chicken meat. Forty strains were isolated from positive samples. Matrix-assisted laser desorption ionization/time of flight mass spectrometry analysis revealed nine distinct clusters and multi-locus sequence typing revealed 34 sequence types including 23 novel sequences, demonstrating high genetic diversity among the isolates. PCR analysis revealed that all the strains contained at least one toxin gene, but none contained the cytK gene. Antibiotic resistance tests revealed that all isolates were classified as multidrug-resistant, with high resistance levels, particularly to ß-lactam antibiotics and vancomycin, but were susceptible to gentamicin. All isolates showed variations in biofilm formation. This study highlights the significant public health risk due to B. cereus s. s. and underscores the need for stringent monitoring and control measures in food production to manage antimicrobial resistance and ensure food safety.
RESUMO
Dystrophic epidermolysis bullosa (DEB) is one of the major types of EB, a rare hereditary group of trauma-induced blistering skin disorders. DEB is caused by inherited pathogenic variants in the COL7A1 gene, which encodes type VII collagen, the major component of anchoring fibrils which maintain adhesion between the outer epidermis and underlying dermis. DEB can be subclassified into dominant (DDEB) and recessive (RDEB) forms. Generally, DDEB has a milder phenotype, while RDEB patients often have more extensive blistering, chronic inflammation, skin fibrosis, and a propensity for squamous cell carcinoma development, collectively impacting on daily activities and life expectancy. At present, best practice treatments are mostly supportive, and thus there is a considerable burden of disease with unmet therapeutic need. Over the last 20 years, considerable translational research efforts have focused on either trying to cure DEB by direct correction of the COL7A1 gene pathology, or by modifying secondary inflammation to lessen phenotypic severity and improve patient symptoms such as poor wound healing, itch, and pain. In this review, we provide an overview and update on various therapeutic innovations for DEB, including gene therapy, cell-based therapy, protein therapy, and disease-modifying and symptomatic control agents. We outline the progress and challenges for each treatment modality and identify likely prospects for future clinical impact.
RESUMO
Contaminated food with antibiotic-resistant Enterococcus spp. could be the vehicle for transmitting Enterococcus to humans and accordingly cause a public health problem. The accumulation of biogenic amines produced by Enterococcus faecalis (E. faecalis) in food may have cytological effects. Bacteriophages (phage in short) are natural antimicrobial agents and can be used alone or in combination with other food preservatives to reduce food microbial contaminants. The aim of this study was to isolate a novel phage against E. faecalis and determine its host range to evaluate its potential application. Bacteriophage, vB_EfKS5, with a broad host range, was isolated to control the growth of E. faecalis. The vB_EfKS5 genome is 59,246 bp in length and has a GC content of 39.7%. The computational analysis of phage vB_EfKS5 genome confirmed that it does not contain any lysogenic, toxic, or virulent genes. Phage vB_EfKS5 exhibited lytic activity against most E. faecalis isolates with different multiplicities of infections and it infected 75.5% (22/29) of E. faecalis isolates and 42.3% (3/7) of E. faecium isolates. It was also able to destroy the biofilm formed by E. faecalis with different MOIs. Phage vB_EfKS5 alone or in combination with nisin could control the growth of E. faecalis in broth and milk. Based on its high productivity, stability, short latent period, and large burst size, phage vB_EfKS5 has a high potential for applications both in food and medical applications.
RESUMO
New therapeutic hope is emerging for people with the rare inherited blistering skin disease recessive dystrophic epidermolysis bullosa (RDEB). Gurevich et al.1 have reported early-phase clinical trial data evaluating a topical herpes simplex virus 1 vector to restore missing type VII collagen in RDEB skin and heal wounds.
Assuntos
Colágeno Tipo VII , Epidermólise Bolhosa Distrófica , Colágeno Tipo VII/genética , Epidermólise Bolhosa Distrófica/genética , Humanos , Pele , CicatrizaçãoRESUMO
In the health systems of many countries, there is neither a requirement to collect a minimum set of demographic information during patient registration nor a standard way of identifying patients. This impedes the provision of integrated, good-quality care for individual patients and, at the system level, prevents generation of the high-quality data necessary for effective management and continuous improvement. Assigning each patient a unique identifier (UID) to create a master patient index (MPI) is therefore essential to ensure data interoperability across all the points of patient care within a health system. Although advances in technology are shifting the boundary between civil registration and personal identification, the additional value of an MPI/UID system lies in the technical and operational capacity to ensure that clinical data are safely and securely managed. Moreover, operationalization of MPI/UID data enables the establishment of an evidence-based, constantly improving "learning health system" with feedback loops that allow measurement, evaluation and visualization of performance over time. The Ministry of Health and Sports of Myanmar is actively engaged in a multistakeholder collaborative process working towards a nationwide MPI/UID system. Demonstration pilots are planned for both online and offline modes of operation for HIV/AIDS, mother and child health (including eliminating mother-to-child transmission of HIV and syphilis) and hospital settings, which are expected to open up the potential for expansion to all health interventions and facilities. With the implementation of the MPI/UID system under way in Myanmar, the Ministry of Health and Sports is laying the foundation to put individuals at the centre of care and deliver a lifelong service for all.
Assuntos
Segurança Computacional , Programas Governamentais , Sistemas de Informação em Saúde/normas , Sistemas de Identificação de Pacientes/normas , Telemedicina , Criança , Feminino , Humanos , Masculino , Serviços de Saúde Materno-Infantil , MianmarRESUMO
Epidermolysis bullosa (EB), the paradigm of heritable skin fragility disorders, is associated with mutations in as many as 20 distinct genes. One of the clinical variants, recessive dystrophic EB (RDEB), demonstrates sub-lamina densa blistering accompanied by alterations in anchoring fibrils due to mutations in COL7A1. In this study, we characterized a patient with widespread connective tissue abnormalities, including skin blistering similar to that in RDEB. Whole exome sequencing, combined with genome-wide homozygosity mapping, identified a homozygous missense mutation in PLOD3 encoding lysyl hydroxylase 3 (LH3). No mutations in COL7A1, the gene previously associated with RDEB, were detected. The level of LH3 was dramatically reduced in the skin and fibroblast cultures from the patient. The blistering in the skin occurred below the lamina densa and was associated with variable density and morphology of anchoring fibrils. The level of type VII collagen expression in the skin was markedly reduced. Analysis of hydroxylysine and its glycosylated derivatives (galactosyl-hydroxylysine and glucosyl-galactosyl-hydroxylysine) revealed marked reduction in glycosylated hydroxylysine. Collectively, these findings indicate that PLOD3 mutations can result in a dystrophic EB-like phenotype in the spectrum of connective tissue disorders and add it to the list of candidate genes associated with skin fragility.
Assuntos
Colágeno Tipo VII/deficiência , Epidermólise Bolhosa/genética , Mutação de Sentido Incorreto , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Pré-Escolar , Colágeno Tipo VII/genética , Regulação para Baixo , Epidermólise Bolhosa/classificação , Homozigoto , Humanos , Masculino , Sequenciamento do ExomaRESUMO
Netherton syndrome (NS) is a rare autosomal recessive skin disorder caused by mutations in SPINK5. It is a debilitating condition with notable mortality in the early years of life. There is no curative treatment. We undertook a nonrandomized, open-label, feasibility, and safety study using autologous keratinocytes transduced with a lentiviral vector encoding SPINK5 under the control of the human involucrin promoter. Six NS subjects were recruited, and gene-modified epithelial sheets were successfully generated in three of five subjects. The sheets exhibited expression of correctly sized lympho-epithelial Kazal-type-related inhibitor (LEKTI) protein after modification. One subject was grafted with a 20 cm2 gene-modified graft on the left anterior thigh without any adverse complications and was monitored by serial sampling for 12 months. Recovery within the graft area was compared against an area outside by morphology, proviral copy number and expression of the SPINK5 encoded protein, LEKTI, and its downstream target kallikrein 5, which exhibited transient functional correction. The study confirmed the feasibility of generating lentiviral gene-modified epidermal sheets for inherited skin diseases such as NS, but sustained LEKTI expression is likely to require the identification, targeting, and engraftment of long-lived keratinocyte stem cell populations for durable therapeutic effects. Important learning points for the application of gene-modified epidermal sheets are discussed.
Assuntos
Células Epidérmicas/metabolismo , Epiderme/metabolismo , Epiderme/transplante , Síndrome de Netherton/genética , Síndrome de Netherton/terapia , Transdução Genética , Transgenes , Adolescente , Adulto , Autoenxertos , Biomarcadores , Técnicas de Cultura de Células , Feminino , Imunofluorescência , Expressão Gênica , Engenharia Genética , Terapia Genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Imuno-Histoquímica , Queratinócitos/metabolismo , Lentivirus/genética , Masculino , Mutação , Síndrome de Netherton/metabolismo , Síndrome de Netherton/patologia , Inibidor de Serinopeptidase do Tipo Kazal 5/genética , Inibidor de Serinopeptidase do Tipo Kazal 5/metabolismo , Resultado do Tratamento , Adulto JovemRESUMO
Frontal fibrosing alopecia (FFA) is a recently described inflammatory and scarring type of hair loss affecting almost exclusively women. Despite a dramatic recent increase in incidence the aetiopathogenesis of FFA remains unknown. We undertake genome-wide association studies in females from a UK cohort, comprising 844 cases and 3,760 controls, a Spanish cohort of 172 cases and 385 controls, and perform statistical meta-analysis. We observe genome-wide significant association with FFA at four genomic loci: 2p22.2, 6p21.1, 8q24.22 and 15q2.1. Within the 6p21.1 locus, fine-mapping indicates that the association is driven by the HLA-B*07:02 allele. At 2p22.1, we implicate a putative causal missense variant in CYP1B1, encoding the homonymous xenobiotic- and hormone-processing enzyme. Transcriptomic analysis of affected scalp tissue highlights overrepresentation of transcripts encoding components of innate and adaptive immune response pathways. These findings provide insight into disease pathogenesis and characterise FFA as a genetically predisposed immuno-inflammatory disorder driven by HLA-B*07:02.
Assuntos
Alopecia/congênito , Loci Gênicos , Predisposição Genética para Doença , Antígeno HLA-B7/genética , Transcriptoma/imunologia , Imunidade Adaptativa , Alopecia/diagnóstico , Alopecia/genética , Alopecia/fisiopatologia , Estudos de Casos e Controles , Estudos de Coortes , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/imunologia , Feminino , Expressão Gênica , Genoma Humano , Estudo de Associação Genômica Ampla , Antígeno HLA-B7/imunologia , Humanos , Imunidade Inata , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUNDRecessive dystrophic epidermolysis bullosa (RDEB) is a severe form of skin fragility disorder due to mutations in COL7A1 encoding basement membrane type VII collagen (C7), the main constituent of anchoring fibrils (AFs) in skin. We developed a self-inactivating lentiviral platform encoding a codon-optimized COL7A1 cDNA under the control of a human phosphoglycerate kinase promoter for phase I evaluation.METHODSIn this single-center, open-label phase I trial, 4 adults with RDEB each received 3 intradermal injections (~1 × 106 cells/cm2 of intact skin) of COL7A1-modified autologous fibroblasts and were followed up for 12 months. The primary outcome was safety, including autoimmune reactions against recombinant C7. Secondary outcomes included C7 expression, AF morphology, and presence of transgene in the injected skin.RESULTSGene-modified fibroblasts were well tolerated, without serious adverse reactions or autoimmune reactions against recombinant C7. Regarding efficacy, there was a significant (P < 0.05) 1.26-fold to 26.10-fold increase in C7 mean fluorescence intensity in the injected skin compared with noninjected skin in 3 of 4 subjects, with a sustained increase up to 12 months in 2 of 4 subjects. The presence of transgene (codon-optimized COL7A1 cDNA) was demonstrated in the injected skin at month 12 in 1 subject, but no new mature AFs were detected.CONCLUSIONTo our knowledge, this is the first human study demonstrating safety and potential efficacy of lentiviral fibroblast gene therapy with the presence of COL7A1 transgene and subsequent C7 restoration in vivo in treated skin at 1 year after gene therapy. These data provide a rationale for phase II studies for further clinical evaluation.TRIAL REGISTRATIONClincalTrials.gov NCT02493816.FUNDINGCure EB, Dystrophic Epidermolysis Bullosa Research Association (UK), UK NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, and Fondation René Touraine Short-Exchange Award.
Assuntos
Epidermólise Bolhosa Distrófica/terapia , Fibroblastos , Terapia Genética , Lentivirus/genética , Adulto , Colágeno Tipo VII/genética , Feminino , Fibroblastos/metabolismo , Fibroblastos/transplante , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Recessive dystrophic epidermolysis bullosa (RDEB) is a rare inherited skin and mucous membrane fragility disorder complicated by early-onset, highly malignant cutaneous squamous cell carcinomas (SCCs). The molecular etiology of RDEB SCC, which arises at sites of sustained tissue damage, is unknown. We performed detailed molecular analysis using whole-exome, whole-genome, and RNA sequencing of 27 RDEB SCC tumors, including multiple tumors from the same patient and multiple regions from five individual tumors. We report that driver mutations were shared with spontaneous, ultraviolet (UV) light-induced cutaneous SCC (UV SCC) and head and neck SCC (HNSCC) and did not explain the early presentation or aggressive nature of RDEB SCC. Instead, endogenous mutation processes associated with apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC) deaminases dominated RDEB SCC. APOBEC mutation signatures were enhanced throughout RDEB SCC tumor evolution, relative to spontaneous UV SCC and HNSCC mutation profiles. Sixty-seven percent of RDEB SCC driver mutations was found to emerge as a result of APOBEC and other endogenous mutational processes previously associated with age, potentially explaining a >1000-fold increased incidence and the early onset of these SCCs. Human papillomavirus-negative basal and mesenchymal subtypes of HNSCC harbored enhanced APOBEC mutational signatures and transcriptomes similar to those of RDEB SCC, suggesting that APOBEC deaminases drive other subtypes of SCC. Collectively, these data establish specific mutagenic mechanisms associated with chronic tissue damage. Our findings reveal a cause for cancers arising at sites of persistent inflammation and identify potential therapeutic avenues to treat RDEB SCC.
Assuntos
Desaminases APOBEC/genética , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/genética , Citosina Desaminase/genética , Epidermólise Bolhosa Distrófica/enzimologia , Epidermólise Bolhosa Distrófica/genética , Mutação/genética , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Variações do Número de Cópias de DNA/genética , Reparo do DNA/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Mutagênese/genética , Taxa de Mutação , Transcriptoma/genéticaRESUMO
Cells therapies, engineered to secrete replacement proteins, are being developed to ameliorate otherwise debilitating diseases. Recessive dystrophic epidermolysis bullosa (RDEB) is caused by defects of type VII collagen, a protein essential for anchoring fibril formation at the dermal-epidermal junction. Whereas allogeneic fibroblasts injected directly into the dermis can mediate transient disease modulation, autologous gene-modified fibroblasts should evade immunological rejection and support sustained delivery of type VII collagen at the dermal-epidermal junction. We demonstrate the feasibility of such an approach using a therapeutic grade, self-inactivating-lentiviral vector, encoding codon-optimized COL7A1, to transduce RDEB fibroblasts under conditions suitable for clinical application. Expression and secretion of type VII collagen was confirmed with transduced cells exhibiting supranormal levels of protein expression, and ex vivo migration of fibroblasts was restored in functional assays. Gene-modified RDEB fibroblasts also deposited type VII collagen at the dermal-epidermal junction of human RDEB skin xenografts placed on NOD-scid IL2Rgamma(null) recipients, with reconstruction of human epidermal structure and regeneration of anchoring fibrils at the dermal-epidermal junction. Fibroblast-mediated restoration of protein and structural defects in this RDEB model strongly supports proposed therapeutic applications in man.