RESUMO
Carboxyl nanodiamond (cND) nanoparticles are actively internalized by B16F10 melanoma cells in culture. Treatment of B16F10 tumor cells with cNDs in vitro inhibited their ability to (i) migrate and invade through porous membranes in a transwell culture system, (ii) secrete matrix metalloproteinases (MMPs) MMP-2 and MMP-9, and (iii) express selected epithelial-mesenchymal transition markers critical for cell migration and invasion. Administration of luciferase-transfected B16F10-Luc2 melanoma cells resulted in a rapid growth of the tumor and its metastasis to different organs that could be monitored by in vivo bioluminescence imaging as well as by ex vivo BLI of the mouse organs. After tumor cells were administered intravenously in C57Bl/6 mice, administration of cNDs (50â µg i.v. every alternate day) resulted in marked suppression of the tumor growth and metastasis in different organs of mice. Subcutaneous administration of B16F10 cells resulted in robust growth of the primary tumor subcutaneously as well as its metastasis to the lungs, liver, spleen, and kidneys. Intravenous treatment with cNDs did not affect the growth of the primary tumor mass but essentially blocked the metastasis of the tumor to different organs. Histological examination of mouse organs indicated that the administration of cNDs by itself was safe and did not cause toxic changes in mouse organs. These results indicate that the cND treatment may have an antimetastatic effect on the spread of B16F10 melanoma tumor cells in mice. Further exploration of cNDs as a possible antimetastatic therapeutic agent is suggested.
RESUMO
The association of pulmonary fibrosis with COVID-19 patients has now been adequately acknowledged and caused a significant number of mortalities around the world. As automatic disease detection has now become a crucial assistant to clinicians to obtain fast and precise results, this study proposes an architecture based on an ensemble machine learning approach to detect COVID-19-associated pulmonary fibrosis. The paper discusses Extreme Gradient Boosting (XGBoost) and its tuned hyper-parameters to optimize the performance for the prediction of severe COVID-19 patients who developed pulmonary fibrosis after 90 days of hospital discharge. A dataset comprising Electronic Health Record (EHR) and corresponding High-resolution computed tomography (HRCT) images of chest of 1175 COVID-19 patients has been considered, which involves 725 pulmonary fibrosis cases and 450 normal lung cases. The experimental results achieved an accuracy of 98%, precision of 99% and sensitivity of 99%. The proposed model is the first in literature to help clinicians in keeping a record of severe COVID-19 cases for analyzing the risk of pulmonary fibrosis through EHRs and HRCT scans, leading to less chance of life-threatening conditions.
RESUMO
Brain tumor is caused by the uncontrolled and accelerated multiplication of cells in the brain. If not treated early enough, it can lead to death. Despite multiple significant efforts and promising research outcomes, accurate segmentation and classification of tumors remain a challenge. The changes in tumor location, shape, and size make brain tumor identification extremely difficult. An Extreme Gradient Boosting (XGBoost) algorithm using is proposed in this work to classify four subtypes of brain tumor-normal, gliomas, meningiomas, and pituitary tumors. Because the dataset was limited in size, image augmentation using a conditional Generative Adversarial Network (cGAN) was used to expand the training data. Deep features, Two-Dimensional Fractional Fourier Transform (2D-FrFT) features, and geometric features are fused together to extract both global and local information from the Magnetic Resonance Imaging (MRI) scans. The model attained enhanced performance with a classification accuracy of 98.79% and sensitivity of 98.77% for the test images. In comparison to state-of-the-art algorithms employing the Kaggle brain tumor dataset, the suggested model showed a considerable improvement. The improved results show the prominence of feature fusion and establish XGBoost as an appropriate classifier for brain tumor detection in terms on testing accuracy, sensitivity and Area under receiver operating characteristic (AUROC) curve.
RESUMO
This study has explored the effect of acid-functionalized single-walled carbon nanotubes (AF-SWCNTs) on Hematopoietic Stem and Progenitor Cell (HSPCs) in mouse bone marrow. Administration of AF-SWCNTs induced a significant decline in the live-cell recovery from bone marrow. Lin-negative Stem cell enriched HSPCs internalized AF-SWCNTs that remained localized in cytoplasmic areas. Incubation of HSPCs with AF-SWCNTs resulted in induction of cell death, inhibition of cell cycle, and induction of reactive oxygen species (ROS) as well as the expression of Caspase 3, 7 and 9 enzymes. In vitro culture with a cytokine cocktail (SCF, GM-CSF, IL3, IL6, IL7) induced differentiation of HSPCs into lymphocytes and myeloid cells, that was inhibited in presence of AF-SWCNTs. Relative recoveries of lymphocytes specifically B lymphocytes, was significantly reduced by AF-SWCNT-treatment, whereas the relative recovery of myeloid cells remained unaltered. These results suggest that AF-SWCNTs have significant toxic effects on HSPCs and differentially suppress the ontogeny of lymphoid and myeloid cells.
RESUMO
The present study is focused on the modulation of Mycobacterium bovis BCG-induced inflammatory response by poly-dispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNTs) in macrophages. Flow cytometric and confocal microscopy studies indicated that both BCG and AF-SWCNTs were efficiently internalized by RAW 264.7 and MH-S macrophage cell lines and were essentially localized in the cytoplasmic area. BCG-induced production of reactive oxygen species (ROS) and nitric oxide by the two cell lines was significantly inhibited by AF-SWCNTs. Using RT-PCR technique, a marked decline was observed in the expression of BCG-induced pro-inflammatory genes COX-2, iNOS, TNF-α, IL-6, and IL-1ß upon treatment with AF-SWCNTs. Results of gelatin zymography indicated that the AF-SWCNTs treatment also induced a marked decline in BCG-induced release of matrix metalloproteinases MMP-2 and MMP-9 by the two macrophage cell lines. The anti-inflammatory effect of AF-SWCNTs in downregulating BCG-induced inflammatory response was further validated in murine peritoneal macrophages. Treatment with AF-SWCNTs led to a steep decline in BCG-induced NO production in murine peritoneal macrophages in vitro as well as in vivo. Peritoneal macrophages isolated from mice treated with BCG and AF-SWCNTs had a significantly lower intracellular expression of COX-2 as compared to the peritoneal macrophages derived from mice treated with BCG alone. Taken together, our results demonstrate a potent anti-inflammatory effect of AF-SWCNTs in alleviating BCG-induced inflammatory responses in macrophages in vitro and in vivo.
Assuntos
Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/prevenção & controle , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Nanotubos de Carbono , Animais , Vacina BCG/toxicidade , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Citometria de Fluxo , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/metabolismo , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
Proliferation and migration of lung epithelial cells following the injury to the epithelial lining of alveoli and airways in the lung are pivotal for remodeling and repair of the wound to restore normal lung function. In the present study, we examined the modulatory effect of carboxylated nanodiamonds (cNDs) on the cell division, migration, and adhesion of epithelial cells in the well-established in vitro model of wound repair and cell migration. Flow cytometry and confocal microscopy results indicated that both LA4 and A549 cells effectively internalized fluorescent carboxylated nanodiamonds (cFNDs) and the internalized nanodiamonds were essentially localized in the cytoplasmic region. Treatment with cNDs blocked the division and migration of cells to fill the scratch wound. Live cell imaging and time-lapse videography of the wound healing process indicated a significant inhibition of cell proliferation activity in cND-treated cells and blocked the wound repair process. Trans-well cell-migration assay results further support the inhibitory effect of cNDs on the cell migration process. Western blotting and immunofluorescence staining indicated that the crucial proteins involved in epithelial-mesenchymal transition (EMT) and cell migration i.e. ß-catenin, Vimentin, NM-myosin, and Focal Adhesion Kinase (FAK) were downregulated after treatment with cNDs, while the expression of E-cadherin and Claudin-1, major cell adhesion markers remained unaltered. Taken together, our results indicate that the decline in cell proliferation activity, downregulation in the expression of various crucial protein like ß-Catenin, NM-myosin, FAK, and Vimentin involved in the cell migration and unaltered expression of cell adhesion molecules E-cadherin and Claudin-1, may be the factors that contribute to the cND-mediated inhibition of EMT during the wound repair process in the monolayers of lung epithelial cells.
Assuntos
Movimento Celular , Proliferação de Células , Células Epiteliais/efeitos dos fármacos , Pulmão/citologia , Nanodiamantes , Animais , Linhagem Celular Tumoral , Humanos , CamundongosRESUMO
Graft versus host disease (GVHD) results from hyper-activation of transplanted lymphocytes against the host antigens. Bone marrow transplantation in humans as well as some cases of blood transfusion and organ transplantation are associated with a strong GVH reaction resulting in GVHD that in many cases may be fatal. We had previously shown that poly-dispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNTs) specifically target activated T and B lymphocytes and kill them. In the present study, efficacy of AF-SWCNTs to suppress the GVH reaction was tested in the mouse model. Acute GVHD was induced in mice by administering intravenously 30 or 60 million spleen cells from a parental strain (C57bl/6 mouse, MHC haplotype H-2b) to host (C57bl/6 x Balb/c) F1 mice (MHC haplotype H-2b/d)and waiting for 8-10 days. Chronic GVHD was similarly induced by administration of 30 million parent spleen cells to F1 mice and waiting for a period of 60 days. Our results demonstrate a marked decline in splenomegaly and recovery of spleen T (both CD4 and CD8) and B cells in GVHD mice treated with AF-SWCNTs. AF-SWCNTs treatment also limited T and B cell proliferation by restricting S-phage of cell cycle. Generation of anti-host cytotoxic T cells (CTLs) was also markedly suppressed by AF-SWCNT treatment of acute GVHD mice, and a significant reduction in the generation of anti-host antibodies could also be demonstrated. Taken together, our results suggest that the AF-SWCNTs can be considered as a potential therapeutic agent for treating GVHD.
Assuntos
Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Doença Enxerto-Hospedeiro/terapia , Nanopartículas/uso terapêutico , Doença Aguda , Animais , Células Cultivadas , Doença Crônica , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/imunologia , Humanos , Terapia de Imunossupressão , Isoantígenos/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nanotubos de CarbonoRESUMO
Due to their unique properties, carbon nanotubes (CNTs) are being widely explored for industrial and medical applications. This has necessitated a thorough assessment of the effect of CNTs on human and animal physiology and health. Impact of CNTs on epithelial tight junctions has not been evaluated in the context of their toxic effects in many biological systems. In the present study, we examined the effect of acid functionalized single-walled carbon nanotubes (AF-SWCNTs) on the function and expression of two tight junction proteins (ZO-1 and occludin) in the Madin-Darby canine kidney (MDCK) cell line. Treatment of MDCK cells with AF-SWCNT resulted in a downregulation of tight junction proteins, decreased trans-epithelial electrical resistance (TER), increased paracellular permeability, and disruption of tight junctions. Taken together, our data demonstrate that AF-SWCNT disrupts tight junction barrier by downregulating tight junction proteins in MDCK epithelial cells.
Assuntos
Células Epiteliais/metabolismo , Nanotubos de Carbono/efeitos adversos , Ocludina/metabolismo , Permeabilidade , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Cães , Células Madin Darby de Rim CaninoRESUMO
Weak codon bias in short exons and separation by a short intron induces difficulty in extracting period-3 component that marks the presence of exonic regions. The annotation task of such short exons has been addressed in the proposed model independent signal processing based method with following features: (a) DNA sequences have been mapped using multiple mapping schemes, (b) period-3 spectrums corresponding to multiple mappings have been optimized to enhance short exon-short intron discrimination, and (c) spectrums corresponding to multiple mapping schemes have been subjected to Principal Component Analysis (PCA) for identifying greater number of such short exons. A comparative study with other methods indicates improved detection of contiguous short exons disunited by a short intron. Apart from the annotation of exonic and intronic regions, the proposed algorithm can also complement the methods for the detection of alternative splicing by intron retention, as one of the characteristic feature for intron retention is the presence of two short exons flanking a short intron.
Assuntos
Biologia Computacional/métodos , Éxons/genética , Íntrons/genética , Análise de Sequência de DNA/métodos , Algoritmos , Animais , DNA/química , DNA/genética , Humanos , Camundongos , Análise de Componente Principal , Processamento de Sinais Assistido por ComputadorRESUMO
Activated mouse B cells as compared to the resting B cells are known to internalize substantially more acid-functionalized single walled carbon nanotubes (AF-SWCNTs). It was hypothesized that the antigens coupled to AF-SWCNTs would also be taken up more efficiently by B cells. Further the enhanced uptake of the antigen by B cells may facilitate antigen presentation by B cells resulting in a better antibody response. Aim of this study was to test this hypothesis. Ovalbumin was chemically coupled to AF-SWCNTs that yielded a coupled product that had 0.08% of all carbon atoms in AF-SWCNTs occupied by ovalbumin. Coupling of ovalbumin to AF-SWCNTs was confirmed by staining the product with anti-ovalbumin antibodies. B cells incubated with ovalbumin-AF-SWCNT internalized more ovalbumin than the B cells incubated with free ovalbumin. Groups of mice were immunized subcutaneously with (a) free ovalbumin, (b) free ovalbumin and AF-SWCNTs at two different subcutaneous sites respectively on mice, and (c) ovalbumin-AF-SWCNT coupled product. In each case a primary immunization was followed by three weekly booster doses. It was found that the anti-ovalbumin antibody response assessed by ELISA, was highest in the group where ovalbumin coupled to AF-SWCNTs was used for immunization (pâ¯<â¯0.001). Antibody response in ovalbumin-AF-SWCNT group was comparable to the group where ovalbumin was used for immunization using complete and incomplete Freund's adjuvant (primary and secondary immunizations respectively). We propose that AF-SWCNTs could be explored as an adjuvant to improve the antibody response especially in vaccine development.
Assuntos
Linfócitos B/imunologia , Macrófagos/imunologia , Nanotubos de Carbono/química , Ovalbumina/imunologia , Adjuvantes Imunológicos , Animais , Formação de Anticorpos , Apresentação de Antígeno , Linfócitos B/metabolismo , Imunização/métodos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Uptake of polydispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNTs) in resting and LPS-activated B cells was studied using fluorescence-tagged AF-SWCNTs (FAF-SWCNTs). Activated B cells internalized substantially higher amounts of FAF-SWCNTs [76.5% AF-SWCNT+ B cells, mean fluorescence intensity (MFI) 720.6] as compared to the resting B cells [39.5% AF-SWCNT+ B cells, MFI 198.5]. B cells in S and G2/M phases were found to have significantly higher uptake of FAF-SWCNTs as compared to cells in G0/G1 phase. Confocal microscopy indicated that AF-SWCNTs were essentially localized on cell membrane in resting B cells, whereas in activated B cells, AF-SWCNTs were distributed throughout the cytoplasm. Targeting of AF-SWCNTs specifically to activated B cells in vivo was examined by first administering intravenously LPS-activated B cells tagged with fluorescence tracer (CFSE) in mice, followed by FAF-SWCNTs through the same route. It was found that FAF-SWCNTs were specifically taken up by CFSE+CD19+-activated B cells (95% FAF-SWCNT+ B cells, MFI 3725) as compared to CFSE- CD19+ resting B cells (31.1% FAF-SWCNT+ B cells, MFI 428). Administration (i.v.) of LPS resulted in a significant increase in the proportion of B cell in mouse spleen that was reduced by 68% by administering AF-SWCNTs. In control mice, the corresponding decrease in B cell proportion was 49%, which was significantly lower (p < 0.005) than the decline in LPS-treated mice. These results indicate that AF-SWCNTs may have the potential as an agent for depleting activated B cells in vivo.
Assuntos
Linfócitos B/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Animais , Linfócitos B/imunologia , Linfócitos B/ultraestrutura , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoplasma/efeitos dos fármacos , Citoplasma/imunologia , Citoplasma/ultraestrutura , Fluorescência , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologiaRESUMO
Presentation of a prototype lipid antigen α-Galactosylceramide (αGC) was examined on primary epithelial cells derived from mouse lungs and on bronchoalveolar lavage (BAL) cells that essentially comprise alveolar macrophages. Presence of CD1d molecules coupled to αGC was demonstrated on both types of cells pre-treated with αGC, suggesting that both cell types are equipped to present lipid antigens. Internalization of Mycobacterium bovis Bacillus Calmette-Guérin (BCG: a prototype pathogen), a pre-requisite to the processing and presentation of protein as well as lipid antigens, was clearly demonstrated in primary lung epithelial (PLE) cells as well as BAL cells. Both PLE and BAL cells expressed CD1d molecule and a significant up-regulation of its expression occurred upon infection of these cells with BCG. Besides CD1d, the expression of other important molecules that participate in lipid antigen presentation pathway (i.e. microsomal triglyceride transfer protein (MTTP), scavenger receptor B1 (SR-B1) and Saposin) was also significantly upregulated in PLE and BAL cells upon BCG infection. In situ up-regulation of CD1d expression on lung epithelial cells was also demonstrated in the lungs of mice exposed intra-tracheally to BCG. Taken together these results suggest that lung epithelial cells may have the ability to present lipid antigens and this pathway seems to get significantly upregulated in response to BCG infection.
Assuntos
Apresentação de Antígeno , Antígenos de Bactérias/imunologia , Antígenos CD1d/imunologia , Células Epiteliais/imunologia , Galactosilceramidas/imunologia , Pulmão/imunologia , Mycobacterium bovis/imunologia , Mucosa Respiratória/imunologia , Animais , Proteínas de Transporte/imunologia , Células Epiteliais/citologia , Pulmão/citologia , Camundongos , Mucosa Respiratória/citologia , Receptores Depuradores Classe B/imunologiaRESUMO
Stem cell research is a rapidly developing field that offers effective treatment for a variety of malignant and non-malignant diseases. Stem cell is a regenerative medicine associated with the replacement, repair, and restoration of injured tissue. Stem cell research is a promising field having maximum therapeutic potential. Cancer stem cells (CSCs) are the cells within the tumor that posses capacity of selfrenewal and have a root cause for the failure of traditional therapies leading to re-occurrence of cancer. CSCs have been identified in blood, breast, brain, and colon cancer. Traditional therapies target only fast growing tumor mass, but not slow-dividing cancer stem cells. It has been shown that embryonic pathways such as Wnt, Hedgehog and Notch, control self-renewal capacity and involved in cancer stem cell maintenance. Targeting of these pathways may be effective in eradicating cancer stem cells and preventing chemotherapy and radiotherapy resistance. Targeting CSCs has become one of the most effective approaches to improve the cancer survival by eradicating the main root cause of cancer. The present review will address, in brief, the importance of cancer stem cells in targeting cancer as better and effective treatment along with a concluding outlook on the scope and challenges in the implication of cancer stem cells in translational oncology.
Assuntos
Neoplasias Encefálicas/terapia , Neoplasias da Mama/terapia , Neoplasias do Colo/terapia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hematológicas/terapia , Células-Tronco/citologia , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , Humanos , Terapia de Alvo Molecular/métodos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Receptores Notch/antagonistas & inibidores , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/genética , Proteínas Wnt/metabolismoRESUMO
Repeated weekly injections of rat erythrocytes produced autoimmune hemolytic anemia (AIHA) in C57BL/6 mice after 5-6 weeks. Using the double in vivo biotinylation (DIB) technique, recently developed in our laboratory, turnover of erythrocyte cohorts of different age groups during AIHA was monitored. Results indicate a significant decline in the proportion of reticulocytes, young and intermediate age groups of erythrocytes, but a significant increase in the proportion of old erythrocytes in blood circulation. Binding of the autoantibody was relatively higher to the young erythrocytes and higher levels of intracellular reactive oxygen species (ROS) were also seen in these cells. Erythropoietic activity in the bone marrows and the spleen of AIHA induced mice was examined by monitoring the relative proportion of erythroid cells at various stages of differentiation in these organs. Cells at different stages of differentiation were enumerated flow cytometrically by double staining with anti-Ter119 and anti-transferrin receptor (CD71) monoclonal antibodies. Erythroid cells in bone marrow declined significantly in AIHA induced mice, erythroblast C being most affected (50% decline). Erythroblast C also recorded high intracellular ROS level along with increased levels of membrane-bound autoantibody. No such decline was observed in spleen. A model of AIHA has been proposed indicating that binding of autoantibodies may not be a sufficient condition for destruction of erythroid cells in bone marrow and in blood circulation. Last stage of erythropoietic differentiation in bone marrow and early stages of erythrocytes in blood circulation are specifically susceptible to removal in AIHA.
Assuntos
Anemia Hemolítica Autoimune/sangue , Autoanticorpos/metabolismo , Eritrócitos/citologia , Reticulócitos/citologia , Anemia Hemolítica Autoimune/imunologia , Animais , Células da Medula Óssea/citologia , Diferenciação Celular , Modelos Animais de Doenças , Eritrócitos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Reticulócitos/imunologia , Baço/citologiaRESUMO
The interaction of poly-dispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNT) with NK cells undergoing activation was examined. Exposure to AF-SWCNT during NK activation in vitro by interleukin (IL)-2, and in vivo by Poly(I:C) significantly lowered cytotoxic activity generated against YAC-1 tumor cells. Recoveries of spleen NK1.1(+) cells as well as the activated subset of NK cells (NK1.1(+)CD69(+) cells) were significantly reduced by the AF-SWCNT exposure. The proportion of apoptotic NK cells (NK1.1(+) phosphatidylserine(+)) in the spleen cell preparations activated in vitro was also significantly elevated. Expression levels of CD107a [for assessing NK cell degranulation] as well as of FasL marker [mediating non-secretory pathway of NK cell killing] were significantly lower in cells exposed to AF-SWCNT during the activation phase. Intracellular levels of interferon (IFN)-γ and tumor necrosis factor (TNF)-α in the cells were also significantly reduced. Fluorescent AF-SWCNT (FAF-SWCNT) were internalized by the NK cells and uptake was significantly greater in activated cells. Confocal microscopy indicated the internalized FAF-SWCNT were localized to the cytoplasm of the NK cells. These results indicated that AF-SWCNT were internalized by NK cells and caused a general down-regulation of a variety of parameters associated with NK cell cytotoxicity and other cellular functions.
Assuntos
Células Matadoras Naturais/imunologia , Linfoma/imunologia , Nanotubos de Carbono , Animais , Apoptose , Degranulação Celular , Linhagem Celular Tumoral , Citoplasma/metabolismo , Citotoxicidade Imunológica , Regulação para Baixo , Interferon gama/metabolismo , Interleucina-2/metabolismo , Ativação Linfocitária , Camundongos , Nanotubos de Carbono/estatística & dados numéricos , Neoplasias Experimentais , Poli I-C/imunologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Feeding cadmium chloride (50 or 1000 ppm CdCl2 in drinking water, ad libitum) to C57BL/6 mice resulted in a significant and sustained fall in blood erythrocyte count and hemoglobin levels that started 4 and 3 weeks after the start of 50 and 1000 ppm cadmium doses respectively. A transient yet significant reticulocytosis occurred during the first 4 weeks of cadmium treatment. Using the recently developed double in vivo biotinylation (DIB) technique, turnover of erythrocyte cohorts of different age groups was simultaneously monitored in control and cadmium treated mice. A significant accumulation of younger erythrocytes and a concomitant decline in the relative proportions of older erythrocytes in circulation was observed in both 50 and 1000 ppm cadmium groups indicating that older erythrocytes were preferentially eliminated in cadmium induced anemia. A significant increase in the erythropoietin levels in plasma was seen in mice exposed to 1000 ppm cadmium. Levels of inflammatory cytokines (IL1A, IL6, TNFα, IFNγ) were however not significantly altered in cadmium treated mice. A significant increase in cellular levels of reactive oxygen species (ROS) was observed in older erythrocytes in circulation but not in younger erythrocytes. Erythropoietic activity in the bone marrows and spleens of cadmium treated mice was examined by monitoring the relative proportion of cells belonging to the erythroid line of differentiation in these organs. Erythroid cells in bone marrow declined markedly (about 30%) in mice in the 1000 ppm cadmium group but the decline was not significant in the 50 ppm cadmium group. Cells representing various stages of erythroid differentiation in bone marrow and spleen were enumerated flow cytometrically by double staining with anti-Ter119 and anti-transferrin receptor (CD71) monoclonal antibodies. Decline of erythroid cells was essentially confined to pro-erythroblast and erythroblast-A, along with a concurrent increase in the splenic erythroid population indicating a stress response. In short cadmium exposure causes preferential clearance of older erythrocytes from circulation along with a depressed erythropoietic activity at higher doses.
Assuntos
Anemia/sangue , Anemia/patologia , Medula Óssea/patologia , Cádmio/toxicidade , Envelhecimento Eritrocítico/efeitos dos fármacos , Eritrócitos/metabolismo , Eritropoese/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Antígeno CD47/metabolismo , Diferenciação Celular/efeitos dos fármacos , Citocinas/sangue , Células Eritroides/efeitos dos fármacos , Células Eritroides/patologia , Eritropoetina/sangue , Mediadores da Inflamação/metabolismo , Cinética , Masculino , Camundongos Endogâmicos C57BL , Fosfatidilserinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reticulócitos/efeitos dos fármacos , Reticulócitos/metabolismo , Baço/efeitos dos fármacos , Baço/patologiaRESUMO
Administration of poly-dispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNTs, 10 µg intravenously on alternate days) induced a sustained anemia in mice. Using a modified double in vivo biotinylation (DIB) technique, blood counts of reticulocytes and erythrocytes of different age groups were simultaneously enumerated in control and AF-SWCNT treated mice. A sustained reticulocytosis was observed in AF-SWCNT treated mice. Young erythrocytes (up to 7 days old) that are normally resistant to elimination in control mice were eliminated at a significant rate in AF-SWCNT treated mice. Old erythrocytes, however, accumulated in circulation indicating that younger erythrocytes were selectively eliminated from the blood circulation of AF-SWCNT treated mice. Cells representing various stages of erythroid differentiation in bone marrow and spleen were enumerated flow cytometrically by double staining with anti-Ter119 and anti-transferrin receptor (CD71) monoclonal antibodies. Proportion of erythroid cells was significantly reduced (up to 27%) in bone marrow (BM) indicating a fall in erythropoietic activity. A concomitant increase in the spleen erythroid population was however observed that could be a compensatory response. Changes in erythroid populations in bone marrow and spleen correlated with changes in erythroblast-A population in these organs that represent an early stage of erythroid differentiation. Uptake of intravenously administered fluorescence tagged AF-SWCNTs (FAF-SWCNTs) was relatively low (3-4%) in erythroid cells in bone marrow and spleen. A significantly higher proportion of pro-erythroblasts and erythroblast-A (early stages of erythroid differentiation) took-up FAF-SWCNTs. Uptake of AF-SWCNTs by early precursors of erythroid differentiation with toxic consequences may be a contributing factor in AF-SWCNT induced anemia.
Assuntos
Anemia/induzido quimicamente , Anemia/fisiopatologia , Medula Óssea/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritropoese/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Baço/efeitos dos fármacos , Animais , Medula Óssea/fisiopatologia , Eritropoese/fisiologia , Citometria de Fluxo , Camundongos , Reticulócitos/efeitos dos fármacos , Baço/fisiopatologiaRESUMO
Effect of poly-dispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNTs) was examined on lipid antigen presentation through CD1d pathway on three cell lines, LA4, MHS, and JAWSII used as prototype antigen presenting cells (APCs). CD1d molecule was expressed on 80-90% MHS (prototype macrophages) and JAWSII (prototype dendritic cells) cells whereas <5% LA4 cells (lung epithelial cells, non-classical APCs) expressed CD1d. Treatment with AF-SWCNTs but not with pristine SWCNTs resulted in a significant decline in the level of CD1d mRNA as well as mRNA levels of some other intracellular proteins involved in lipid antigen presentation pathway (MTP, ApoE, prosaposin, SR-BI and LDLr). Lipid antigen presentation was assessed by first incubating the cells with a prototype lipid antigen (α-Glactosylceramide or αGC) and then staining with L363 monoclonal antibody that detects αGC bound to CD1d molecule. While 100% MHS and JAWSII cells presented αGC, only 20% LA4 cells presented the CD1d antigen. Treatment with AF-SWCNTs resulted in a 30-40% decrease in αGC antigen presentation in all three cell lines. These results show that AF-SWCNT treatment down regulated the lipid antigen presentation pathway in all three cell lines and significantly lowered the ability of these cell lines to present αGC antigen.
Assuntos
Apresentação de Antígeno/efeitos dos fármacos , Antígenos CD1d/imunologia , Células Dendríticas/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Nanotubos de Carbono , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Células Epiteliais/imunologia , Galactosilceramidas/imunologia , Macrófagos/imunologia , CamundongosRESUMO
Microsatellites are tandem repeats of size 1-6 base pairs, associated with various diseases, DNA fingerprinting, and also useful in evolutionary studies. A signal processing algorithm for microsatellite detection, based on adaptive S-transform is proposed. The standard deviation of the Gaussian window kernel of the S-transform has been optimized for integer periods of interest by maximizing the concentration measure. The time-frequency plot is generated using optimal standard deviation values. Candidate repeats are marked by comparing the spectrogram values in the time-frequency plot with a threshold. A preprocessing phase followed by a verification phase extracts final results from the candidate repeats. Simulation studies on DNA sequences establish the superiority of this algorithm over other existing methods. Applicability of this algorithm in the analysis of DNA sequences associated with repeat expansion diseases has also been demonstrated.