RESUMO
The devil facial tumour disease (DFTD) has led to a massive decline in the wild Tasmanian devil (Sarcophilus harrisii) population. The disease is caused by two independent devil facial tumours (DFT1 and DFT2). These transmissible cancers have a mortality rate of nearly 100â%. An adenoviral vector-based vaccine has been proposed as a conservation strategy for the Tasmanian devil. This study aimed to determine if a human adenovirus serotype 5 could express functional transgenes in devil cells. As DFT1 cells do not constitutively express major histocompatibility complex class I (MHC-I), we developed a replication-deficient adenoviral vector that encodes devil interferon gamma (IFN-γ) fused to a fluorescent protein reporter. Our results show that adenoviral-expressed IFN-γ was able to stimulate upregulation of beta-2 microglobulin, a component of MHC-I, on DFT1, DFT2 and devil fibroblast cell lines. This work suggests that human adenoviruses can serve as a vaccine platform for devils and potentially other marsupials.
Assuntos
Infecções por Adenoviridae , Adenovírus Humanos , Neoplasias Faciais , Marsupiais , Animais , Humanos , Adenovírus Humanos/genética , Interferon gama , Adenoviridae/genética , Neoplasias Faciais/genética , Neoplasias Faciais/veterinária , Antígenos de Histocompatibilidade Classe I/genéticaRESUMO
MHC-I and MHC-II molecules are critical components of antigen presentation and T cell immunity to pathogens and cancer. The two monoclonal transmissible devil facial tumours (DFT1, DFT2) exploit MHC-I pathways to overcome immunological anti-tumour and allogeneic barriers. This exploitation underpins the ongoing transmission of DFT cells across the wild Tasmanian devil population. We have previously shown that the overexpression of NLRC5 in DFT1 and DFT2 cells can regulate components of the MHC-I pathway but not MHC-II, establishing the stable upregulation of MHC-I on the cell surface. As MHC-II molecules are crucial for CD4+ T cell activation, MHC-II expression in tumour cells is beginning to gain traction in the field of immunotherapy and cancer vaccines. The overexpression of Class II transactivator in transfected DFT1 and DFT2 cells induced the transcription of several genes of the MHC-I and MHC-II pathways. This was further supported by the upregulation of MHC-I protein on DFT1 and DFT2 cells, but interestingly MHC-II protein was upregulated only in DFT1 cells. This new insight into the regulation of MHC-I and MHC-II pathways in cells that naturally overcome allogeneic barriers can inform vaccine, immunotherapy and tissue transplant strategies for human and veterinary medicine.
Assuntos
Neoplasias Faciais , Marsupiais , Animais , Neoplasias Faciais/genética , Neoplasias Faciais/veterinária , Neoplasias Faciais/patologia , Antígenos de Histocompatibilidade Classe II , Peptídeos e Proteínas de Sinalização Intracelular , Marsupiais/genéticaRESUMO
The identification of practical early diagnostic biomarkers is a cornerstone of improved prevention and treatment of cancers. Such a case is devil facial tumor disease (DFTD), a highly lethal transmissible cancer afflicting virtually an entire species, the Tasmanian devil (Sarcophilus harrisii). Despite a latent period that can exceed one year, to date DFTD diagnosis requires visual identification of tumor lesions. To enable earlier diagnosis, which is essential for the implementation of effective conservation strategies, we analyzed the extracellular vesicle (EV) proteome of 87 Tasmanian devil serum samples using data-independent acquisition mass spectrometry approaches. The antimicrobial peptide cathelicidin-3 (CATH3), released by innate immune cells, was enriched in serum EV samples of both devils with clinical DFTD (87.9% sensitivity and 94.1% specificity) and devils with latent infection (i.e., collected while overtly healthy, but 3-6 months before subsequent DFTD diagnosis; 93.8% sensitivity and 94.1% specificity). Although high expression of antimicrobial peptides has been mostly related to inflammatory diseases, our results suggest that they can be also used as accurate cancer biomarkers, suggesting a mechanistic role in tumorous processes. This EV-based approach to biomarker discovery is directly applicable to improving understanding and diagnosis of a broad range of diseases in other species, and these findings directly enhance the capacity of conservation strategies to ensure the viability of the imperiled Tasmanian devil population.
Assuntos
Vesículas Extracelulares , Neoplasias Faciais , Marsupiais , Animais , Peptídeos Catiônicos Antimicrobianos , Detecção Precoce de Câncer , Vesículas Extracelulares/patologia , Neoplasias Faciais/diagnóstico , Neoplasias Faciais/veterinária , CatelicidinasRESUMO
The iconic Tasmanian devil (Sarcophilus harrisii) is endangered due to the transmissible cancer Devil Facial Tumour Disease (DFTD), of which there are two genetically independent subtypes (DFT1 and DFT2). While DFT1 and DFT2 can be differentially diagnosed using tumour biopsies, there is an urgent need to develop less-invasive biomarkers that can detect DFTD and distinguish between subtypes. Extracellular vesicles (EVs), the nano-sized membrane-enclosed vesicles present in most biofluids, represent a valuable resource for biomarker discovery. Here, we characterized the proteome of EVs from cultured DFTD cells using data-independent acquisition-mass spectrometry and an in-house spectral library of > 1500 proteins. EVs from both DFT1 and DFT2 cell lines expressed higher levels of proteins associated with focal adhesion functions. Furthermore, hallmark proteins of epithelial-mesenchymal transition were enriched in DFT2 EVs relative to DFT1 EVs. These findings were validated in EVs derived from serum samples, revealing that the mesenchymal marker tenascin-C was also enriched in EVs derived from the serum of devils infected with DFT2 relative to those infected with DFT1 and healthy controls. This first EV-based investigation of DFTD increases our understanding of the cancers' EVs and their possible involvement in DFTD progression, such as metastasis. Finally, we demonstrated the potential of EVs to differentiate between DFT1 and DFT2, highlighting their potential use as less-invasive liquid biopsies for the Tasmanian devil.
Assuntos
Biomarcadores Tumorais/sangue , Vesículas Extracelulares/metabolismo , Neoplasias Faciais/classificação , Neoplasias Faciais/diagnóstico , Marsupiais/metabolismo , Proteoma/análise , Tenascina/sangue , Animais , Diagnóstico Diferencial , Neoplasias Faciais/sangue , Espectrometria de Massas , Proteoma/metabolismoRESUMO
PURPOSE OF REVIEW: Immune checkpoint immunotherapies (ICI) are now approved for over 20 types of cancer and there are almost 6000 ongoing clinical trials investigating immuno-modulators as cancer therapies. This review investigated the effect of monoclonal antibody-based immune checkpoint immunotherapies when combined with cytokine therapy. We reviewed published clinical trial results from 2005 to 2020 for studies that used approved monoclonal antibody ICI in combination with the cytokines. Studies that met the search criteria were assessed for treatment efficacy and immunological changes associated with treatment. RECENT FINDING: ICI often fails to result in improved clinical outcomes for patients and lasting protection from cancer recurrence. The use of pro-inflammatory cytokines alongside ICI has been shown to enhance the efficacy of these therapies in vitro and in animal studies. However, the results in human clinical trials are less clear and many clinical trials do not publish results at the end of the trial. A deeper understanding of the molecular interactions between cytokines, tumors, and immune cells is needed to improve overall ICI outcomes and design combination trials. Critical examination of the design and characteristics of previous clinical trials can provide insight into the lack of effective clinical translation for many immunotherapeutic drugs.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Citocinas/uso terapêutico , Imunoterapia/métodos , Neoplasias/terapia , Animais , Terapia Combinada , Humanos , Interleucina-2/uso terapêutico , Ipilimumab/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologiaRESUMO
PURPOSE: Downregulation of MHC class I (MHC-I) is a common immune evasion strategy of many cancers. Similarly, two allogeneic clonal transmissible cancers have killed thousands of wild Tasmanian devils (Sarcophilus harrisii) and also modulate MHC-I expression to evade anti-cancer and allograft responses. IFNG treatment restores MHC-I expression on devil facial tumor (DFT) cells but is insufficient to control tumor growth. Transcriptional co-activator NLRC5 is a master regulator of MHC-I in humans and mice but its role in transmissible cancers remains unknown. In this study, we explored the regulation and role of MHC-I in these unique genetically mis-matched tumors. METHODS: We used transcriptome and flow cytometric analyses to determine how MHC-I shapes allogeneic and anti-tumor responses. Cell lines that overexpress NLRC5 to drive antigen presentation, and B2M-knockout cell lines incapable of presenting antigen on MHC-I were used to probe the role of MHC-I in rare cases of tumor regressions. RESULTS: Transcriptomic results suggest that NLRC5 plays a major role in MHC-I regulation in devils. NLRC5 was shown to drive the expression of many components of the antigen presentation pathway but did not upregulate PDL1. Serum from devils with tumor regressions showed strong binding to IFNG-treated and NLRC5 cell lines; antibody binding to IFNG-treated and NRLC5 transgenic tumor cells was diminished or absent following B2M knockout. CONCLUSION: MHC-I could be identified as a target for anti-tumor and allogeneic immunity. Consequently, NLRC5 could be a promising target for immunotherapy and vaccines to protect devils from transmissible cancers and inform development of transplant and cancer therapies for humans.
Assuntos
Apresentação de Antígeno/imunologia , Biomarcadores Tumorais/metabolismo , Neoplasias Faciais/imunologia , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Animais , Biomarcadores Tumorais/genética , Neoplasias Faciais/genética , Neoplasias Faciais/metabolismo , Neoplasias Faciais/patologia , Antígenos de Histocompatibilidade Classe I/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Marsupiais , Transcriptoma , Células Tumorais CultivadasRESUMO
Immune evasion is critical to the growth and survival of cancer cells. This is especially pertinent to transmissible cancers, which evade immune detection across genetically diverse hosts. The Tasmanian devil (Sarcophilus harrisii) is threatened by the emergence of Devil Facial Tumour Disease (DFTD), comprising two transmissible cancers (DFT1 and DFT2). The development of effective prophylactic vaccines and therapies against DFTD has been restricted by an incomplete understanding of how allogeneic DFT1 and DFT2 cells maintain immune evasion upon activation of tumour-specific immune responses. In this study, we used RNA sequencing to examine tumours from three experimental DFT1 cases. Two devils received a vaccine prior to inoculation with live DFT1 cells, providing an opportunity to explore changes to DFT1 cancers under immune pressure. Analysis of DFT1 in the non-immunised devil revealed a 'myelinating Schwann cell' phenotype, reflecting both natural DFT1 cancers and the DFT1 cell line used for the experimental challenge. Comparatively, immunised devils exhibited a 'dedifferentiated mesenchymal' DFT1 phenotype. A third 'immune-enriched' phenotype, characterised by increased PDL1 and CTLA-4 expression, was detected in a DFT1 tumour that arose after immunotherapy. In response to immune pressure, mesenchymal plasticity and upregulation of immune checkpoint molecules are used by human cancers to evade immune responses. Similar mechanisms are associated with immune evasion by DFTD cancers, providing novel insights that will inform modification of DFTD vaccines. As DFT1 and DFT2 are clonal cancers transmitted across genetically distinct hosts, the Tasmanian devil provides a 'natural' disease model for more broadly exploring these immune evasion mechanisms in cancer.
Assuntos
Neoplasias Faciais , Marsupiais , Vacinas , Animais , Neoplasias Faciais/terapia , Humanos , Imunoterapia , VacinaçãoRESUMO
Devil Facial Tumour Disease (DFTD) is an emerging infectious disease that provides an excellent example of how diagnostic techniques improve as disease-specific knowledge is generated. DFTD manifests as tumour masses on the faces of Tasmanian devils, first noticed in 1996. As DFTD became more prevalent among devils, karyotyping of the lesions and their devil hosts demonstrated that DFTD was a transmissible cancer. The subsequent routine diagnosis relied on microscopy and histology to characterise the facial lesions as cancer cells. Combined with immunohistochemistry, these techniques characterised the devil facial tumours as sarcomas of neuroectodermal origin. More sophisticated molecular methods identified the origin of DFTD as a Schwann cell, leading to the Schwann cell-specific protein periaxin to discriminate DFTD from other facial lesions. After the discovery of a second facial cancer (DFT2), cytogenetics and the absence of periaxin expression confirmed the independence of the new cancer from DFT1 (the original DFTD). Molecular studies of the two DFTDs led to the development of a PCR assay to differentially diagnose the cancers. Proteomics and transcriptomic studies identified different cell phenotypes among the two DFTD cell lines. Phenotypic differences were also reflected in proteomics studies of extracellular vesicles (EVs), which yielded an early diagnostic marker that could detect DFTD in its latent stage from serum samples. A mesenchymal marker was also identified that could serve as a serum-based differential diagnostic. The emergence of two transmissible cancers in one species has provided an ideal opportunity to better understand transmissible cancers, demonstrating how fundamental research can be translated into applicable and routine diagnostic techniques.
RESUMO
Immune checkpoint immunotherapy is a pillar of human oncology treatment with potential for non-human species. The first checkpoint immunotherapy approved for human cancers targeted the CTLA4 protein. CTLA4 can inhibit T cell activation by capturing and internalizing CD80 and CD86 from antigen presenting cells, a process called trans-endocytosis. Similarly, CD28 can capture CD80 and CD86 via trogocytosis and retain the captured ligands on the surface of the CD28-expressing cells. The wild Tasmanian devil (Sarcophilus harrisii) population has declined by 77% due to transmissible cancers that evade immune defenses despite genetic mismatches between the host and tumors. We used a live cell-based assay to demonstrate that devil CTLA4 and CD28 can capture CD80 and CD86. Mutation of evolutionarily conserved motifs in CTLA4 altered functional interactions with CD80 and CD86 in accordance with patterns observed in other species. These results suggest that checkpoint immunotherapies can be translated to evolutionarily divergent species.
Assuntos
Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Antígenos CD28/metabolismo , Antígeno CTLA-4/metabolismo , Marsupiais/imunologia , Motivos de Aminoácidos/genética , Animais , Antígenos CD28/antagonistas & inibidores , Células CHO , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/genética , Células Cultivadas , Clonagem Molecular , Cricetulus , Espécies em Perigo de Extinção , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Microscopia Intravital , Marsupiais/metabolismo , Mutação , TrogocitoseRESUMO
Our understanding of the impact of in utero exposure to PM on post-natal immune function and the subsequent response to PM exposure is limited. Similarly, very few studies have considered the effect of exposure to PM from different sources. Thus, the aim of this study was to examine how in utero exposure to PM from different sources effects the post-natal response to pro-inflammatory and immune stimuli. C56BL/6J pregnant mice were exposed intranasally on gestational day (E)7.5, E12.5 and E17.5-50 µg of diesel exhaust particles (DEP), silica or saline. At 4-weeks post-natal age, sub-groups of male and female mice were exposed intranasally to 50 µg of DEP or saline. Lung inflammatory responses were assessed 6 h later by quantifying inflammatory cells and cytokine production (MCP-1, MIP-2, IL-6). In separate groups of mice, the spleen was harvested to quantify B and T cell populations. Splenocytes were isolated and exposed to lipopolysaccharide or poly I:C for assessment of cytokine production. Exposure to DEP in utero decreased %CD1dhighCD5+ B cells in female mice and IFN-γ production by splenocytes in both sexes. Male mice had elevations in macrophage and lymphocyte numbers in response to DEP whereas female mice only had elevated IL-6, MCP-1 and MIP-2 levels. In utero exposure to silica had no effect on these measures. These data suggest that in utero exposure to PM alters immune development and post-natal immune function. This response is dependent on the source of PM, which has implications for understanding the community health effects of exposure to air pollution.
Assuntos
Poluição do Ar , Emissões de Veículos , Animais , Feminino , Lipopolissacarídeos , Pulmão , Masculino , Camundongos , Material Particulado/toxicidade , Gravidez , Dióxido de Silício/toxicidade , Emissões de Veículos/toxicidadeRESUMO
Around 40% of humans and Tasmanian devils (Sarcophilus harrisii) develop cancer in their lifetime, compared to less than 10% for most species. In addition, devils are affected by two of the three known transmissible cancers in mammals. Immune checkpoint immunotherapy has transformed human medicine, but a lack of species-specific reagents has limited checkpoint immunology in most species. We developed a cut-and-paste reagent development system and used the fluorescent fusion protein system to show that immune checkpoint interactions are conserved across 160,000,000 years of evolution, CD200 is highly expressed on transmissible tumor cells, and coexpression of CD200R1 can block CD200 surface expression. The system's versatility across species was demonstrated by fusing a fluorescent reporter to a camelid-derived nanobody that binds human programmed death ligand 1. The evolutionarily conserved pathways suggest that naturally occurring cancers in devils and other species can be used to advance our understanding of cancer and immunological tolerance.
Assuntos
Neoplasias Faciais , Marsupiais , Animais , Neoplasias Faciais/metabolismo , Neoplasias Faciais/patologia , Evasão da Resposta Imune , ImunoterapiaRESUMO
Devil facial tumor disease (DFTD) encompasses two independent transmissible cancers that have killed the majority of Tasmanian devils. The cancer cells are derived from Schwann cells and are spread between devils during biting, a common behavior during the mating season. The Centers for Disease Control and Prevention (CDC) defines a parasite as "An organism that lives on or in a host organism and gets its food from, or at, the expense of its host." Most cancers, including DFTD, live within a host organism and derive resources from its host, and consequently have parasitic-like features. Devil facial tumor disease is a transmissible cancer and, therefore, DFTD shares one additional feature common to most parasites. Through direct contact between devils, DFTD has spread throughout the devil population. However, unlike many parasites, the DFTD cancer cells have a simple lifecycle and do not have either independent, vector-borne, or quiescent phases. To facilitate a description of devil facial tumor disease, this review uses life cycles of parasites as an analogy.
RESUMO
The Tasmanian devil (Sarcophilus harrisii) is the only mammalian species known to be affected by multiple transmissible cancers. Devil facial tumours 1 and 2 (DFT1 and DFT2) are independent neoplastic cell lineages that produce large, disfiguring cancers known as devil facial tumour disease (DFTD). The long-term persistence of wild Tasmanian devils is threatened due to the ability of DFTD cells to propagate as contagious allografts and the high mortality rate of DFTD. Recent studies have demonstrated that both DFT1 and DFT2 cancers originated from founder cells of the Schwann cell lineage, an uncommon origin of malignant cancer in humans. This unprecedented finding has revealed a potential predisposition of Tasmanian devils to transmissible cancers of the Schwann cell lineage. In this review, we compare the molecular nature of human Schwann cells and nerve sheath tumours with DFT1 and DFT2 to gain insights into the emergence of transmissible cancers in the Tasmanian devil. We discuss a potential mechanism, whereby Schwann cell plasticity and frequent wounding in Tasmanian devils combine with an inherent cancer predisposition and low genetic diversity to give rise to transmissible Schwann cell cancers in devils on rare occasions.
Assuntos
Neoplasias Faciais/veterinária , Marsupiais , Animais , Neoplasias Faciais/genética , Neoplasias Faciais/patologia , Humanos , Neoplasias de Bainha Neural/genética , Neoplasias de Bainha Neural/veterinária , Células de Schwann/fisiologiaRESUMO
Introduction: The Tasmanian devil (Sarcophilus harrisii) is the largest extant carnivorous marsupial. Since 1996, its population has declined by 77% primarily due to a clonal transmissible tumor, known as devil facial tumor (DFT1) disease. In 2014, a second transmissible devil facial tumor (DFT2) was discovered. DFT1 and DFT2 are nearly 100% fatal.Areas covered: We review DFT control approaches and propose a rabies-style oral bait vaccine (OBV) platform for DFTs. This approach has an extensive safety record and was a primary tool in large-scale rabies virus elimination from wild carnivores across diverse landscapes. Like rabies virus, DFTs are transmitted by oral contact, so immunizing the oral cavity and stimulating resident memory cells could be advantageous. Additionally, exposing infected devils that already have tumors to OBVs could serve as an oncolytic virus immunotherapy. The primary challenges may be identifying appropriate DFT-specific antigens and optimization of field delivery methods.Expert opinion: DFT2 is currently found on a peninsula in southern Tasmania, so an OBV that could eliminate DFT2 should be the priority for this vaccine approach. Translation of an OBV approach to control DFTs will be challenging, but the approach is feasible for combatting ongoing and future disease threats.
Assuntos
Vacinas Anticâncer/administração & dosagem , Neoplasias Faciais/prevenção & controle , Vacinação/métodos , Administração Oral , Animais , Vacinas Anticâncer/imunologia , Neoplasias Faciais/imunologia , Neoplasias Faciais/veterinária , Humanos , Imunoterapia/métodos , Marsupiais/imunologia , Terapia Viral Oncolítica/métodos , Tasmânia , Vacinação/veterináriaRESUMO
Devil facial tumour disease (DFTD) comprises two genetically distinct transmissible cancers (DFT1 and DFT2) endangering the survival of the Tasmanian devil (Sarcophilus harrisii) in the wild. DFT1 first arose from a cell of the Schwann cell lineage; however, the tissue-of-origin of the recently discovered DFT2 cancer is unknown. In this study, we compared the transcriptome and proteome of DFT2 tumours to DFT1 and normal Tasmanian devil tissues to determine the tissue-of-origin of the DFT2 cancer. Our findings demonstrate that DFT2 expresses a range of Schwann cell markers and exhibits expression patterns consistent with a similar origin to the DFT1 cancer. Furthermore, DFT2 cells express genes associated with the repair response to peripheral nerve damage. These findings suggest that devils may be predisposed to transmissible cancers of Schwann cell origin. The combined effect of factors such as frequent nerve damage from biting, Schwann cell plasticity and low genetic diversity may allow these cancers to develop on rare occasions. The emergence of two independent transmissible cancers from the same tissue in the Tasmanian devil presents an unprecedented opportunity to gain insight into cancer development, evolution and immune evasion in mammalian species.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Faciais/veterinária , Marsupiais/fisiologia , Proteoma/análise , Células de Schwann/patologia , Transcriptoma , Animais , Biomarcadores Tumorais/genética , Neoplasias Faciais/genética , Neoplasias Faciais/metabolismo , Neoplasias Faciais/patologia , Humanos , Células de Schwann/metabolismoRESUMO
Macrophages have emerged as a key component of the innate immune system that emigrates to peripheral tissues during gestation and in the adult organism. Their complex pathway to maturity, their unique plasticity and their various roles as effector and regulatory cells during an immune response have been the focus of intense research. A class of surface molecules, the G-Protein coupled receptors (GPCRs) play important roles in many immune processes. They have drawn attention in regard to these functions and the potential for therapeutic targets that can modulate the response of immune cells in pathologies such as diabetes, atherosclerosis, and chronic inflammatory diseases. Of the more than 800 GPCRs identified, ~100 are currently targeted with drugs which have had their activity investigated in vivo. Macrophages express a number of GPCRs which have central roles during cell differentiation and in the regulation of their functions. While some macrophage GPCRs such as chemokine receptors have been studied in great detail, the roles of other receptors of this large family are still not well understood. This review summarizes new insights into macrophage biology, differences of human, and mouse macrophages and gives details of some of the GPCRs expressed by this cell type.
Assuntos
Diferenciação Celular/imunologia , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Biomarcadores , Diferenciação Celular/genética , Humanos , Imunidade Inata , Ativação de Macrófagos/genética , Macrófagos/citologia , Camundongos , Especificidade de Órgãos , Receptores Acoplados a Proteínas G/genética , Transdução de SinaisRESUMO
BACKGROUND: Little is known about the effect of pregnancy on the response to particulate matter. The aim of this study was to determine if pregnancy increases the susceptibility to PM from different sources using a mouse model. METHODS: Pregnant, eight-week-old C57BL/6J mice were exposed intranasally to 50⯵g of diesel exhaust particles (DEP), iron oxide (Fe2O3) or silica (SiO2) in 50⯵L of saline, or saline alone, on gestational day (E)7.5, E12.5 and E17.5. Groups of non-pregnant mice were exposed on day (D)0, D5 and D10. Biological samples were collected 24â¯h after the last exposure. Serum IL-4 and IL-6 levels were quantified by ELISA. Bronchoalveolar lavage (BAL) fluid was collected for inflammatory cells counts and assessment of IFN-É£, IL-4, IL-5, IL-6, IL-8 and IL-10 levels by ELISA. The spleen and thymus were also collected and the percentage of B cells and CD4+, CD8+ and CD4+CD25â¯+â¯T cells were determined by flow cytometry. RESULTS: Exposure to silica caused an influx of lymphocytes, eosinophils and neutrophils into the lung. The magnitude of this response was suppressed by pregnancy. Pregnancy also enhanced the production of CD4+CD25â¯+â¯T cells in response to DEP and silica exposure. CONCLUSIONS: Collectively, our data suggest that pregnancy reduces the inflammatory response to silica and alters the immune response to DEP. These responses were accompanied by pregnancy related changes including increased IL-4 production, reduced IL-8 production and an increase in the proportion of CD4+CD25â¯+â¯T cells in response to PM exposure.
Assuntos
Inflamação/prevenção & controle , Material Particulado/toxicidade , Gravidez/fisiologia , Sistema Respiratório/patologia , Emissões de Veículos/toxicidade , Animais , Citocinas/metabolismo , Exposição Ambiental/efeitos adversos , Feminino , Compostos Férricos , Pulmão/patologia , Contagem de Linfócitos , Camundongos , Camundongos Endogâmicos C57BL , Sistema Respiratório/efeitos dos fármacos , Dióxido de Silício , Fatores de TempoRESUMO
Introduction: Macrophage phagocytosis of pathogens and tumour cells is an important early event in protection against infectious disease and cancer. As tumour necrosis factor α (TNF) is an important cytokine in macrophage activation, we investigated the involvement of TNF in macrophage phagocytosis of tumour cells. Methods: We used Devil Facial Tumour Disease (DFTD) cancer cells as the target tumour cells. The Tasmanian devil (Sarcophilus harrisii) population is threatened by the transmissible DFTD. Using DFTD cells provided the opportunity to determine if these cells can be phagocytosed and investigate requirement for TNF. As effector cells, bone marrow derived macrophages (BMDMs), generated from C57BL/6 wild type (B6.WT) and C57BL/6 TNF-/- (B6.TNF-/-) mice were used. Phagocytosis of DFTD cells was investigated by confocal microscopy and flow cytometry. Results: DFTD cells were consistently phagocytosed by B6.WT and B6.TNF-/- BMDMs with similar efficiency in vitro. Consequently the DFTD cells are not resistant to phagocytosis. Following activation by exposure to IFNγ and LPS or LPS alone, B6.TNF-/- BMDMs had higher phagocytic efficiency and lower nitric oxide (NO) production compared to wild-type controls. In addition, NO seems to be unlikely to be the involved in phagocytosis efficiency in IFNγ and LPS activated B6.TNF-/- macrophages and consequences thereof. Conclusion: Our results indicate that TNF is not required for IFNγ and LPS or LPS alone activation of macrophage phagocytosis. TNF may negatively regulate macrophage phagocytosis of tumour cells.
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Neoplasias Faciais/imunologia , Neoplasias Faciais/veterinária , Macrófagos/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Neoplasias Faciais/patologia , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Marsupiais , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Óxido Nítrico/metabolismo , Fagocitose , Fator de Necrose Tumoral alfa/deficiênciaRESUMO
The Tasmanian devil, a marsupial carnivore, has been restricted to the island state of Tasmania since its extinction on the Australian mainland about 3000 years ago. In the past two decades, this species has experienced severe population decline due to the emergence of devil facial tumor disease (DFTD), a transmissible cancer. During these 20 years, scientists have puzzled over the immunological and evolutionary responses by the Tasmanian devil to this transmissible cancer. Targeted strategies in population management and disease control have been developed as well as comparative processes to identify variation in tumor and host genetics. A multi-disciplinary approach with multi-institutional teams has produced considerable advances over the last decade. This has led to a greater understanding of the molecular pathogenesis and genomic classification of this cancer. New and promising developments in the Tasmanian devil's story include evidence that most immunized, and some wild devils, can produce an immune response to DFTD. Furthermore, epidemiology combined with genomic studies suggest a rapid evolution to the disease and that DFTD will become an endemic disease. Since 1998 there have been more than 350 publications, distributed over 37 Web of Science categories. A unique endemic island species has become an international curiosity that is in the spotlight of integrative and comparative biology research.
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Transmissão de Doença Infecciosa/veterinária , Neoplasias Faciais/veterinária , Animais , Transmissão de Doença Infecciosa/prevenção & controle , Neoplasias Faciais/imunologia , Neoplasias Faciais/patologia , Neoplasias Faciais/prevenção & controle , Marsupiais , TasmâniaRESUMO
BACKGROUND: In utero exposure to particulate matter (PM) from a range of sources is associated with adverse post-natal health; however, the effect of maternal exposure to community-sampled PM on early post-natal lung and immune development is poorly understood. OBJECTIVES: Using a mouse model, we aimed to determine whether in utero exposure to PM alters early post-natal lung function and immune cell populations. We used PM collected from ceiling voids in suburban houses as a proxy for community PM exposure. METHODS: Pregnant C57BL/6 mice were intranasally exposed to ceiling derived PM, or saline alone, at gestational day (E) 13.5, 15.5, and 17.5. When mice were two weeks old, we assessed lung function by the forced oscillation technique, and enumerated T and B cell populations in the spleen and thymus by flow cytometry. RESULTS: Maternal exposure to PM impaired somatic growth of male offspring resulting in reduced lung volume and deficits in lung function. There was no effect on thymic T cell populations in dams and their male offspring but PM decreased the CD4â¯+CD25â¯+â¯T cell population in the female offspring. In contrast, maternal exposure to PM increased splenic CD3â¯+CD4â¯+â¯and CD3â¯+CD8â¯+â¯T cells in dams, and there was some evidence to suggest inhibition of splenic T cell maturation in male but not female offspring. CONCLUSIONS: Our findings suggested that maternal exposure to ceiling void PM has the capacity to impair early somatic growth and alter early life immune development in a sex specific manner.