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2.
Cancer Discov ; 13(6): 1364-1385, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-36977461

RESUMO

Understanding the evolutionary pathways to metastasis and resistance to immune-checkpoint inhibitors (ICI) in melanoma is critical for improving outcomes. Here, we present the most comprehensive intrapatient metastatic melanoma dataset assembled to date as part of the Posthumous Evaluation of Advanced Cancer Environment (PEACE) research autopsy program, including 222 exome sequencing, 493 panel-sequenced, 161 RNA sequencing, and 22 single-cell whole-genome sequencing samples from 14 ICI-treated patients. We observed frequent whole-genome doubling and widespread loss of heterozygosity, often involving antigen-presentation machinery. We found KIT extrachromosomal DNA may have contributed to the lack of response to KIT inhibitors of a KIT-driven melanoma. At the lesion-level, MYC amplifications were enriched in ICI nonresponders. Single-cell sequencing revealed polyclonal seeding of metastases originating from clones with different ploidy in one patient. Finally, we observed that brain metastases that diverged early in molecular evolution emerge late in disease. Overall, our study illustrates the diverse evolutionary landscape of advanced melanoma. SIGNIFICANCE: Despite treatment advances, melanoma remains a deadly disease at stage IV. Through research autopsy and dense sampling of metastases combined with extensive multiomic profiling, our study elucidates the many mechanisms that melanomas use to evade treatment and the immune system, whether through mutations, widespread copy-number alterations, or extrachromosomal DNA. See related commentary by Shain, p. 1294. This article is highlighted in the In This Issue feature, p. 1275.


Assuntos
Neoplasias Encefálicas , Melanoma , Humanos , Melanoma/patologia , Mutação , Evolução Molecular , DNA
4.
Pilot Feasibility Stud ; 8(1): 238, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357934

RESUMO

BACKGROUND: The improved survival rate for many cancers in high-income countries demands a coordinated multidisciplinary approach to survivorship care and service provision to ensure optimal patient outcomes and quality of life. This study assesses the feasibility of introducing a Women's Health Initiative cancer survivorship clinic in Ireland. METHODS: The trial https://spcare.bmj.com/content/9/2/209.short comprises an intervention and control arm. Two hundred participants will be recruited. Key eligibility (1) women with early-stage hormone receptor-positive breast or gynecologic cancer (cervix or endometrial), within 12 months of completion of primary curative therapy, and (2) access to the Internet. The complex intervention comprises a nurse-led clinic targeting symptom management through a trigger alert system, utilizing electronic patient-reported outcome (ePRO) assessments at baseline, and 2, 4, 6, 8, 10, and 12 months. It also includes input from a dietitian monitoring diet and nutritional status. The control group will receive their usual care pathway standard of care and attend the cancer survivorship clinic and complete ePRO assessments at the start and end of the study. The primary endpoint (feasibility) includes the proportion of enrolled participants who complete baseline and follow-up ePRO surveys and partake in health professional consultations after ePRO data triggers. Secondary endpoints include changes in cancer-related symptom scores assessed by ePROs, health-related Quality of Life Questionnaire (QLQ) scores, Appraisal Self-Care Agency-R scores, and adjuvant endocrine therapy medication adherence. A process evaluation will capture the experiences of participation in the study, and the healthcare costs will be examined as part of the economic analysis. Ethical approval was granted in December 2020, with accrual commencing in March 2021. DISCUSSION: This protocol describes the implementation of a parallel arm randomized controlled trial (RCT) which examines the feasibility of delivering a Cancer Survivorship Clinic. The ePRO is an innovative symptom monitoring system which detects the treatment-related effects and provides individualized support for cancer survivors. The findings will provide direction for the implementation of future survivorship care. TRIAL REGISTRATION: ClinicalTrials.gov , NCT05035173 . Retrospectively registered on September 5, 2021.

5.
Cell Rep Med ; 3(10): 100781, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36240755

RESUMO

Patients with blood cancer continue to have a greater risk of inadequate immune responses following three COVID-19 vaccine doses and risk of severe COVID-19 disease. In the context of the CAPTURE study (NCT03226886), we report immune responses in 80 patients with blood cancer who received a fourth dose of BNT162b2. We measured neutralizing antibody titers (NAbTs) using a live virus microneutralization assay against wild-type (WT), Delta, and Omicron BA.1 and BA.2 and T cell responses against WT and Omicron BA.1 using an activation-induced marker (AIM) assay. The proportion of patients with detectable NAb titers and T cell responses after the fourth vaccine dose increased compared with that after the third vaccine dose. Patients who received B cell-depleting therapies within the 12 months before vaccination have the greatest risk of not having detectable NAbT. In addition, we report immune responses in 57 patients with breakthrough infections after vaccination.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Neoplasias , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , Estudos Clínicos como Assunto , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Imunidade , SARS-CoV-2
6.
PLoS One ; 17(10): e0275423, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36190969

RESUMO

BACKGROUND: Little is known about the efficacy of pregnancy screening tools using non-sensitive sociodemographic questions to identify the possible presence of as yet undiagnosed disease in individuals and later adverse childhood events disclosure. OBJECTIVES: The study aims were to: 1) record the prevalence of risk disclosed by families during receipt of a sustained nurse home visiting program; and 2) explore patterns of relationships between the disclosed risks for their child having adverse experiences and the antenatal screening tool, which used non-sensitive demographic questions. DESIGN: Retrospective, observational study. PARTICIPANTS AND METHODS: Data about the participants in the intervention arm of the Australian right@home trial, which is scaffolded on the Maternal Early Childhood Sustained Home-visiting model, collected between 2013 and 2017 were used. Screening data from the 10-item antenatal survey of non-sensitive demographic risk factors and disclosed risks recorded by the nurse in audited case files during the subsequent 2 year intervention were examined (n = 348). Prevalence of disclosed risks for their child having adverse experiences were analysed in 2019 using multiple response frequencies. Phi correlations were conducted to test associations between screening factors and disclosed risks. RESULTS: Among the 348 intervention participants whose files were audited, 300 were noted by nurses to have disclosed risks during the intervention, with an average of four disclosures. The most prevalent maternal disclosures were depression or anxiety (57.8%). Mental health issues were the most prevalent partner and family disclosures. Screening tool questions on maternal smoking in pregnancy, not living with another adult, poverty and self-reporting anxious mood were significantly associated with a number of disclosed risks for their child having adverse experiences. CONCLUSIONS: These findings suggest that a non-sensitive sociodemographic screening tool may help to identify families at higher risk for adverse childhood experiences for whom support from a sustained nurse home visiting program may be beneficial.


Assuntos
Experiências Adversas da Infância , Adulto , Austrália/epidemiologia , Criança , Pré-Escolar , Feminino , Visita Domiciliar , Humanos , Cuidado Pós-Natal , Gravidez , Estudos Retrospectivos
9.
Nat Ecol Evol ; 6(1): 88-102, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34949820

RESUMO

Genetic intra-tumour heterogeneity fuels clonal evolution, but our understanding of clinically relevant clonal dynamics remain limited. We investigated spatial and temporal features of clonal diversification in clear cell renal cell carcinoma through a combination of modelling and real tumour analysis. We observe that the mode of tumour growth, surface or volume, impacts the extent of subclonal diversification, enabling interpretation of clonal diversity in patient tumours. Specific patterns of proliferation and necrosis explain clonal expansion and emergence of parallel evolution and microdiversity in tumours. In silico time-course studies reveal the appearance of budding structures before detectable subclonal diversification. Intriguingly, we observe radiological evidence of budding structures in early-stage clear cell renal cell carcinoma, indicating that future clonal evolution may be predictable from imaging. Our findings offer a window into the temporal and spatial features of clinically relevant clonal evolution.


Assuntos
Neoplasias , Evolução Clonal , Humanos
10.
Cancer Cell ; 40(2): 114-116, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-34968417
11.
Nat Cancer ; 2: 1321-1337, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34950880

RESUMO

CAPTURE (NCT03226886) is a prospective cohort study of COVID-19 immunity in patients with cancer. Here we evaluated 585 patients following administration of two doses of BNT162b2 or AZD1222 vaccines, administered 12 weeks apart. Seroconversion rates after two doses were 85% and 59% in patients with solid and hematological malignancies, respectively. A lower proportion of patients had detectable neutralizing antibody titers (NAbT) against SARS-CoV-2 variants of concern (VOCs) vs wildtype (WT). Patients with hematological malignancies were more likely to have undetectable NAbT and had lower median NAbT vs solid cancers against both WT and VOCs. In comparison with individuals without cancer, patients with haematological, but not solid, malignancies had reduced NAb responses. Seroconversion showed poor concordance with NAbT against VOCs. Prior SARS-CoV-2 infection boosted NAb response including against VOCs, and anti-CD20 treatment was associated with undetectable NAbT. Vaccine-induced T-cell responses were detected in 80% of patients, and were comparable between vaccines or cancer types. Our results have implications for the management of cancer patients during the ongoing COVID-19 pandemic.


Assuntos
Imunidade Adaptativa/imunologia , Anticorpos Neutralizantes/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Carcinoma de Células Renais/complicações , Neoplasias Renais/complicações , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Vacina BNT162/administração & dosagem , Vacina BNT162/imunologia , COVID-19/complicações , COVID-19/epidemiologia , Vacinas contra COVID-19/administração & dosagem , ChAdOx1 nCoV-19/administração & dosagem , ChAdOx1 nCoV-19/imunologia , Feminino , Humanos , Imunogenicidade da Vacina/imunologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Estudos Prospectivos , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Linfócitos T/imunologia , Linfócitos T/virologia , Vacinação/métodos
12.
Cancer Cell ; 39(11): 1497-1518.e11, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34715028

RESUMO

ADAPTeR is a prospective, phase II study of nivolumab (anti-PD-1) in 15 treatment-naive patients (115 multiregion tumor samples) with metastatic clear cell renal cell carcinoma (ccRCC) aiming to understand the mechanism underpinning therapeutic response. Genomic analyses show no correlation between tumor molecular features and response, whereas ccRCC-specific human endogenous retrovirus expression indirectly correlates with clinical response. T cell receptor (TCR) analysis reveals a significantly higher number of expanded TCR clones pre-treatment in responders suggesting pre-existing immunity. Maintenance of highly similar clusters of TCRs post-treatment predict response, suggesting ongoing antigen engagement and survival of families of T cells likely recognizing the same antigens. In responders, nivolumab-bound CD8+ T cells are expanded and express GZMK/B. Our data suggest nivolumab drives both maintenance and replacement of previously expanded T cell clones, but only maintenance correlates with response. We hypothesize that maintenance and boosting of a pre-existing response is a key element of anti-PD-1 mode of action.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Inibidores de Checkpoint Imunológico/administração & dosagem , Neoplasias Renais/tratamento farmacológico , Nivolumabe/administração & dosagem , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T CD8-Positivos , Carcinoma de Células Renais/genética , Ensaios Clínicos Fase II como Assunto , Retrovirus Endógenos/genética , Perfilação da Expressão Gênica/métodos , Genômica/métodos , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias Renais/genética , Nivolumabe/farmacologia , Estudos Prospectivos , Análise de Sequência de RNA , Análise de Célula Única , Evasão Tumoral , Microambiente Tumoral , Sequenciamento do Exoma
13.
Res Sq ; 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34580668

RESUMO

Patients with cancer have higher COVID-19 morbidity and mortality. Here we present the prospective CAPTURE study (NCT03226886) integrating longitudinal immune profiling with clinical annotation. Of 357 patients with cancer, 118 were SARS-CoV-2-positive, 94 were symptomatic and 2 patients died of COVID-19. In this cohort, 83% patients had S1-reactive antibodies, 82% had neutralizing antibodies against WT, whereas neutralizing antibody titers (NAbT) against the Alpha, Beta, and Delta variants were substantially reduced. Whereas S1-reactive antibody levels decreased in 13% of patients, NAbT remained stable up to 329 days. Patients also had detectable SARS-CoV-2-specific T cells and CD4+ responses correlating with S1-reactive antibody levels, although patients with hematological malignancies had impaired immune responses that were disease and treatment-specific, but presented compensatory cellular responses, further supported by clinical. Overall, these findings advance the understanding of the nature and duration of immune response to SARS-CoV-2 in patients with cancer.

14.
Nat Med ; 27(8): 1362-1366, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34040262

RESUMO

Patients with cancer are currently prioritized in coronavirus disease 2019 (COVID-19) vaccination programs globally, which includes administration of mRNA vaccines. Cytokine release syndrome (CRS) has not been reported with mRNA vaccines and is an extremely rare immune-related adverse event of immune checkpoint inhibitors. We present a case of CRS that occurred 5 d after vaccination with BTN162b2 (tozinameran)-the Pfizer-BioNTech mRNA COVID-19 vaccine-in a patient with colorectal cancer on long-standing anti-PD-1 monotherapy. The CRS was evidenced by raised inflammatory markers, thrombocytopenia, elevated cytokine levels (IFN-γ/IL-2R/IL-18/IL-16/IL-10) and steroid responsiveness. The close temporal association of vaccination and diagnosis of CRS in this case suggests that CRS was a vaccine-related adverse event; with anti-PD1 blockade as a potential contributor. Overall, further prospective pharmacovigillence data are needed in patients with cancer, but the benefit-risk profile remains strongly in favor of COVID-19 vaccination in this population.


Assuntos
Vacinas contra COVID-19/efeitos adversos , Neoplasias Colorretais/metabolismo , Síndrome da Liberação de Citocina , COVID-19/metabolismo , COVID-19/prevenção & controle , Humanos , Masculino , SARS-CoV-2/isolamento & purificação
15.
Nat Ecol Evol ; 5(7): 1033-1045, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34002049

RESUMO

The genetic evolutionary features of solid tumour growth are becoming increasingly well described, but the spatial and physical nature of subclonal growth remains unclear. Here, we utilize 102 macroscopic whole-tumour images from clear cell renal cell carcinoma patients, with matched genetic and phenotypic data from 756 biopsies. Utilizing a digital image processing pipeline, a renal pathologist marked the boundaries between tumour and normal tissue and extracted positions of boundary line and biopsy regions to X and Y coordinates. We then integrated coordinates with genomic data to map exact spatial subclone locations, revealing how genetically distinct subclones grow and evolve spatially. We observed a phenotype of advanced and more aggressive subclonal growth in the tumour centre, characterized by an elevated burden of somatic copy number alterations and higher necrosis, proliferation rate and Fuhrman grade. Moreover, we found that metastasizing subclones preferentially originate from the tumour centre. Collectively, these observations suggest a model of accelerated evolution in the tumour interior, with harsh hypoxic environmental conditions leading to a greater opportunity for driver somatic copy number alterations to arise and expand due to selective advantage. Tumour subclone growth is predominantly spatially contiguous in nature. We found only two cases of subclone dispersal, one of which was associated with metastasis. The largest subclones spatially were dominated by driver somatic copy number alterations, suggesting that a large selective advantage can be conferred to subclones upon acquisition of these alterations. In conclusion, spatial dynamics is strongly associated with genomic alterations and plays an important role in tumour evolution.


Assuntos
Variações do Número de Cópias de DNA , Neoplasias , Evolução Molecular , Genômica , Humanos , Mutação
16.
Nat Cancer ; 2(12): 1321-1337, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35121900

RESUMO

Patients with cancer have higher COVID-19 morbidity and mortality. Here we present the prospective CAPTURE study, integrating longitudinal immune profiling with clinical annotation. Of 357 patients with cancer, 118 were SARS-CoV-2 positive, 94 were symptomatic and 2 died of COVID-19. In this cohort, 83% patients had S1-reactive antibodies and 82% had neutralizing antibodies against wild type SARS-CoV-2, whereas neutralizing antibody titers against the Alpha, Beta and Delta variants were substantially reduced. S1-reactive antibody levels decreased in 13% of patients, whereas neutralizing antibody titers remained stable for up to 329 days. Patients also had detectable SARS-CoV-2-specific T cells and CD4+ responses correlating with S1-reactive antibody levels, although patients with hematological malignancies had impaired immune responses that were disease and treatment specific, but presented compensatory cellular responses, further supported by clinical recovery in all but one patient. Overall, these findings advance the understanding of the nature and duration of the immune response to SARS-CoV-2 in patients with cancer.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/imunologia , Neoplasias/complicações , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/mortalidade , Feminino , Seguimentos , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/imunologia , Estudos Prospectivos , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
17.
Nat Cancer ; 2(12): 1305-1320, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35121899

RESUMO

Coronavirus disease 2019 (COVID-19) antiviral response in a pan-tumor immune monitoring (CAPTURE) ( NCT03226886 ) is a prospective cohort study of COVID-19 immunity in patients with cancer. Here we evaluated 585 patients following administration of two doses of BNT162b2 or AZD1222 vaccines, administered 12 weeks apart. Seroconversion rates after two doses were 85% and 59% in patients with solid and hematological malignancies, respectively. A lower proportion of patients had detectable titers of neutralizing antibodies (NAbT) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOC) versus wild-type (WT) SARS-CoV-2. Patients with hematological malignancies were more likely to have undetectable NAbT and had lower median NAbT than those with solid cancers against both SARS-CoV-2 WT and VOC. By comparison with individuals without cancer, patients with hematological, but not solid, malignancies had reduced neutralizing antibody (NAb) responses. Seroconversion showed poor concordance with NAbT against VOC. Previous SARS-CoV-2 infection boosted the NAb response including against VOC, and anti-CD20 treatment was associated with undetectable NAbT. Vaccine-induced T cell responses were detected in 80% of patients and were comparable between vaccines or cancer types. Our results have implications for the management of patients with cancer during the ongoing COVID-19 pandemic.


Assuntos
Vacina BNT162/imunologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19/imunologia , Neoplasias/imunologia , SARS-CoV-2/imunologia , Idoso , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacina BNT162/administração & dosagem , COVID-19/sangue , COVID-19/imunologia , ChAdOx1 nCoV-19/administração & dosagem , Feminino , Humanos , Imunidade Celular , Imunogenicidade da Vacina , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/complicações , Estudos Prospectivos , Linfócitos T/imunologia
18.
Cell ; 183(1): 4-10, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979319

RESUMO

The SARS-CoV-2 pandemic has posed a significant challenge for risk evaluation and mitigation among cancer patients. Susceptibility to and severity of COVID-19 in cancer patients has not been studied in a prospective and broadly applicable manner. CAPTURE is a pan-cancer, longitudinal immune profiling study designed to address this knowledge gap.


Assuntos
Infecções por Coronavirus/complicações , Monitorização Imunológica/métodos , Neoplasias/complicações , Pneumonia Viral/complicações , Anticorpos Antivirais/imunologia , COVID-19 , Infecções por Coronavirus/imunologia , Humanos , Estudos Longitudinais , Neoplasias/imunologia , Neoplasias/virologia , Pandemias , Pneumonia Viral/imunologia
19.
J Ren Nutr ; 29(3): 181-187, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30691727

RESUMO

OBJECTIVE: Vitamin D insufficiency is highly prevalent among renal transplant recipients and in observational studies is associated with adverse outcomes. Hypercalcemia, usually due to persistent hyperparathyroidism, also commonly occurs in this population and often coexists with vitamin D insufficiency. However, concern that vitamin D supplementation might exacerbate the pre-existing hypercalcemia often leads clinicians to avoid vitamin D supplementation in such patients. This feasibility study aimed to quantify the effect on serum calcium of short-term low-dose cholecalciferol supplementation in a group of renal transplant recipients with a recent history of serum calcium levels >10 mg/dL. DESIGN: A 2-week, single arm, open-label trial. SETTING: Renal transplant follow-up clinic in an Irish University Hospital. SUBJECTS: Eighteen vitamin D-insufficient adult patients with a functioning renal allograft (estimated glomerular filtration rate > 30 mL/minute/1.73 m2) and a recent history of serum calcium >10 mg/dL. INTERVENTION: Two weeks of treatment with 1,000 IU cholecalciferol/day. MAIN OUTCOME MEASURE: Change in ionized calcium and urine calcium:creatinine ratio at follow-up compared with baseline. RESULTS: Mean (standard deviation [SD]) baseline 25 (OH) vitamin D (25 (OH) D) concentration was 15.9 (5.97) ng/mL and mean (SD) baseline serum calcium was 10.50 (0.6) mg/dL. Following the 2-week intervention, median (interquartile range [IQR]) change in serum calcium from baseline was -0.08 (-3.6 to 0.08) mg/dL, P = .3. Mean (SD) ionized calcium decreased from 5.24 (0.32) mg/dL at baseline to 5.16 (0.28) mg/dL, P = .05. Median (IQR) change in the urinary calcium:creatinine ratio was 0.001 (-0.026 to 0.299) mg/mg, P = .88. Median (IQR) change in 25 (OH) D was 3.6 (2.9-6.2) ng/mL, P < .05. CONCLUSIONS: In vitamin D-insufficient renal transplant recipients at risk of hypercalcemia, low-dose short-term oral cholecalciferol supplementation improves 25 (OH) D concentrations without exacerbating hypercalcemia or increasing the urinary calcium:creatinine ratio.


Assuntos
Colecalciferol/administração & dosagem , Hipercalcemia/epidemiologia , Transplante de Rim , Transplantados , Deficiência de Vitamina D/tratamento farmacológico , Adulto , Cálcio/sangue , Cálcio/urina , Creatinina/sangue , Suplementos Nutricionais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Vitamina D/análogos & derivados , Vitamina D/sangue
20.
Toxicol Sci ; 128(2): 461-70, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22584686

RESUMO

Suspicion has been raised that high aspect ratio nanoparticles or nanofibers might possess asbestos-like pathogenicity. The pleural space is a specific target for disease in individuals exposed to asbestos and by implication of nanofibers. Pleural effects of fibers depends on fiber length, but the key threshold length beyond which adverse effects occur has never been identified till now because all asbestos and vitreous fiber samples are heterogeneously distributed in their length. Nanotechnology advantageously allows for highly defined length distribution of synthetically engineered fibers that enable for in-depth investigation of this threshold length. We utilized the ability to prepare silver nanofibers of five defined length classes to demonstrate a threshold fiber length for acute pleural inflammation. Nickel nanofibers and carbon nanotubes were then used to strengthen the relationship between fiber length and pleural inflammation. A method of intrapleural injection of nanofibers in female C57Bl/6 strain mice was used to deliver the fiber dose, and we then assessed the acute pleural inflammatory response. Chest wall sections were examined by light and scanning electron microscopy to identify areas of lesion; furthermore, cell-nanowires interaction on the mesothelial surface of the parietal pleura in vivo was investigated. Our results showed a clear threshold effect, demonstrating that fibers beyond 4 µm in length are pathogenic to the pleura. The identification of the threshold length for nanofiber-induced pathogenicity in the pleura has important implications for understanding the structure-toxicity relationship for asbestos-induced mesothelioma and consequent risk assessment with the aim to contribute to the engineering of synthetic nanofibers by the adoption of a benign-by-design approach.


Assuntos
Amianto/toxicidade , Mesotelioma/induzido quimicamente , Nanofibras/toxicidade , Pleurisia/induzido quimicamente , Animais , Feminino , Metais/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Fagocitose
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