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1.
Front Immunol ; 14: 1265038, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37942326

RESUMO

Bovine tuberculosis (bTB), caused by infection with Mycobacterium bovis, continues to cause significant issues for the global agriculture industry as well as for human health. An incomplete understanding of the host immune response contributes to the challenges of control and eradication of this zoonotic disease. In this study, high-throughput bulk RNA sequencing (RNA-seq) was used to characterise differential gene expression in γδ T cells - a subgroup of T cells that bridge innate and adaptive immunity and have known anti-mycobacterial response mechanisms. γδ T cell subsets are classified based on expression of a pathogen-recognition receptor known as Workshop Cluster 1 (WC1) and we hypothesised that bTB disease may alter the phenotype and function of specific γδ T cell subsets. Peripheral blood was collected from naturally M. bovis-infected (positive for single intradermal comparative tuberculin test (SICTT) and IFN-γ ELISA) and age- and sex-matched, non-infected control Holstein-Friesian cattle. γδ T subsets were isolated using fluorescence activated cell sorting (n = 10-12 per group) and high-quality RNA extracted from each purified lymphocyte subset (WC1.1+, WC1.2+, WC1- and γδ-) was used to generate transcriptomes using bulk RNA-seq (n = 6 per group, representing a total of 48 RNA-seq libraries). Relatively low numbers of differentially expressed genes (DEGs) were observed between most cell subsets; however, 189 genes were significantly differentially expressed in the M. bovis-infected compared to the control groups for the WC1.1+ γδ T cell compartment (absolute log2 FC ≥ 1.5 and FDR P adj. ≤ 0.1). The majority of these DEGs (168) were significantly increased in expression in cells from the bTB+ cattle and included genes encoding transcription factors (TBX21 and EOMES), chemokine receptors (CCR5 and CCR7), granzymes (GZMA, GZMM, and GZMH) and multiple killer cell immunoglobulin-like receptor (KIR) proteins indicating cytotoxic functions. Biological pathway overrepresentation analysis revealed enrichment of genes with multiple immune functions including cell activation, proliferation, chemotaxis, and cytotoxicity of lymphocytes. In conclusion, γδ T cells have important inflammatory and regulatory functions in cattle, and we provide evidence for preferential differential activation of the WC1.1+ specific subset in cattle naturally infected with M. bovis.


Assuntos
Mycobacterium bovis , Tuberculose Bovina , Animais , Bovinos , Humanos , Subpopulações de Linfócitos T , Receptores de Antígenos de Linfócitos T gama-delta , Expressão Gênica
2.
Cureus ; 15(3): e36840, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37009351

RESUMO

Aim Since the introduction of the target referral system, there has been controversy about its value and whether it affected the short- and long-term outcomes of colorectal cancer surgeries. With contradicting results, this study highlights differences in personal and tumour characteristics, management differences, and outcomes in each referral pathway, including target pathway referrals for suspected cancers, emergency presentations, routine referrals, and incidentally discovered cancers during screening. Methods A retrospective study of colorectal cancer (CRC) patients operated on between January 1, 2010, and December 31, 2014, with records dating to the end of the five-year follow-up, was extracted anonymously from the database of CRC outcomes at the North Middlesex University Hospital NHS Trust, London. The total number of patients operated on through the four pathways was 176, with full records and competent follow-ups. Patients were classified according to the mode of referral: two-week wait (2WW or target), routine, emergency, and incidental discovery referrals. Comparisons were made between these groups with regard to personal and tumour characteristics, management, and outcome. Results It has been demonstrated by this study that target referrals present mainly with stage I cancers as compared to emergency referrals that present with more stage II (IIa+ IIb+ IIc). The highest percentage of cancer locations within the large bowel was rectal, followed by sigmoid in both target and emergency groups; 8.8% of target patients needed neoadjuvant chemoradiotherapy in the form of FOLFOX (folinic acid, 5-fluorouracil, and oxaliplatin) chemotherapy protocol with the addition of radiotherapy in patients with advanced rectal cancers, compared to 13.3% of emergency patients. Conclusion The colorectal 2WW system was the main pathway supplying colorectal cancer operations; it mostly showed earlier cancers than the other referral groups; its cancers were mostly rectosigmoid with less need for adjuvant chemotherapy; fewer recurrences; and it also showed a lower five-year mortality rate than the emergency group.

3.
Cureus ; 15(3): e36917, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37009365

RESUMO

Background This study aimed to investigate disparities in colorectal cancer (CRC) patients' demographics according to the five major ethnicities of patients living in the catchment area of North Middlesex Hospital. Methodology This retrospective study included CRC patients operated on between January 1, 2010, and December 31, 2014. Records dating to the end of the five-year follow-up were extracted anonymously from a database of CRC outcomes at the North Middlesex University Hospital NHS Trust. Comparisons were made according to ethnicity, patient demographics, type of presentation, cancer location, stage at diagnosis, recurrence, and mortality. Results A total of 176 adult patients were operated on for CRC between January 1, 2010, and December 31, 2014. The majority of the patients were referred as two-week wait target referrals. Emergency presentation of CRC was the highest in White non-UK patients. The White British Irish patients had their tumors mostly in the cecum, followed by the sigmoid colon, while the rectum followed by the sigmoid colon were the most common sites in the Black population. All study populations mainly presented with stage I disease, and the next highest incidence of cancers according to stage and ethnicity was stage IIIb in the Black population. Conclusions Differences in the ethnic background are important factors, especially in a diverse community, which can impact the age and mode of presentation of the disease, as well as the stage it starts to present. The location of the primary tumor, metastases, and recurrence sites are all affected by the ethnic background, which, subsequently, affect the survival of the patient.

4.
Cureus ; 15(3): e36737, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37009370

RESUMO

Aim Colonoscopy and computed tomography (CT) scans of the abdomen and pelvis are routine pre-operative assessment tools in colorectal cancer (CRC) patients. There have been some discrepancies regarding the location of cancer when seen by colonoscopy versus CT scan. The purpose of this study was to compare the accuracy of a colonoscopy with a computed tomography (CT) scan of the abdomen and pelvis with contrast, which is done routinely before surgery to localise the exact site of the tumour within the large bowel, whilst comparing both to the operative, gross and histopathology findings of the exact location. Methods A retrospective study was carried out on 165 colorectal cancer patients operated on between January 1, 2010, and December 31, 2014, using electronic hospital records that were reviewed anonymously, comparing the location of cancer within the large bowels as was found on colonoscopy and CT scan of the abdomen and pelvis with contrast, comparing both to post-operative histopathology specimen or intra-operative assessment in cases where no resection of the primary tumour was performed. Results CT and colonoscopy were both accurate in diagnosing 70.5% of cases that had done both investigations pre-operatively. The best results were obtained when the cancer was located in the caecum as confirmed post-operatively; the combined accuracy rate was 100%. CT was accurate, whilst colonoscopy was not in eight (6.2%) cases (all are rectal or sigmoid cancers), and colonoscopy was accurate and CT was not in 12 cases, 10 of them were rectal and two were ascending colonic. Colonoscopy was not performed in 36 (21%) cases for a variety of reasons, including large bowel obstruction or perforation on presentation. In 32 of these cases, CT scan managed to accurately predict the location of cancer (mostly rectal and caecal), and CT scan was inaccurate in 20.6% of cases (34 out of 165), whilst colonoscopy was inaccurate in 13.9% of cases (18 out of 129). Conclusion Colonoscopy is more accurate in localising colorectal cancers than CT scan of the abdomen and pelvis with contrast. CT scan diagnoses regional and distant spread of colorectal cancers such as nodal status, invasion of neighbouring organs and/or peritoneum and the presence of liver metastases, whilst colonoscopy is limited to intraluminal diagnosis but can be both a diagnostic and therapeutic tool, with higher accuracy, in general, in localising colorectal cancers. Both CT scan and colonoscopy were equal in appendicular, caecal, splenic flexure and descending colon cancer localisation accuracy.

5.
Tuberculosis (Edinb) ; 139: 102327, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36857964

RESUMO

Tuberculosis has a negative economic impact on buffalo farming, and it poses a potential threat to human health. Interferon-gamma (IFN-γ) plays a central role in protection against mycobacterial diseases, illustrating the importance of T-cell mediated immune responses in tuberculosis infection. Recently, the expression of Caspase-3, a critical executor of apoptosis, in M. tuberculosis-specific IFN-γ+CD4+ T cells was used as a new marker to distinguish active from latent tuberculosis infection in humans. The aims of this work were to develop a whole blood flow cytometric assay to detect the production of IFN-γ and the activation of Caspase-3 by CD4+ T lymphocytes from water buffalo and to evaluate whether these parameters can discriminate between healthy and M. bovis naturally infected buffaloes. A total of 35 Italian Mediterranean buffaloes were grouped in two groups: uninfected and M. bovis infected (based on the results of antemortem diagnostic tests: single intradermal tuberculin (SIT) and ELISA IFN-γ tests). Whole blood was incubated for 6 h with tubercular antigens: PPD-B, PPD-A, ESAT-6/CFP-10 and a new mix of precocious secreted antigens (PA). Our results showed a significant increase in the percentage of IFN-γ+CD4+ T cells in infected compared to the uninfected animals after each stimulus. Improved sensitivity of the assay was obtained by including the stimulation with the new mix of PA. Interestingly, we observed a concomitant decrease in percentage of Caspase-3+CD4+ T cells in M. bovis infected animals compared to the control healthy ones, regardless of the stimulus used. Overall, these results showed that M. bovis infection activates CD4+ T lymphocytes to produce IFN-γ and at the same time causes a concomitant decrease of Caspase-3 activation in CD4+ T cells. This study for the first time in water buffalo describes the development of a whole blood flow cytometric assay for the detection of IFN-γ producing CD4+ T cells and proposes the expression of active Caspase-3 as an additional bovine TB biomarker. Although further studies are needed to better understand the mechanisms of Caspase-3-mediated cell death during tuberculosis, our data can help to better understand the cellular immune response to M. bovis infection in buffalo species.


Assuntos
Tuberculose Latente , Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose , Animais , Humanos , Bovinos , Búfalos , Caspase 3/metabolismo , Tuberculose/microbiologia , Interferon gama/metabolismo , Tuberculose Latente/microbiologia , Linfócitos T CD4-Positivos , Tuberculina , Morte Celular , Antígenos de Bactérias
6.
Artigo em Inglês | MEDLINE | ID: mdl-36834227

RESUMO

BACKGROUND: In the last two decades, high-altitude training (HAT) and elevation training masks (ETMs) have been widely used among athletes to enhance physical performance. However, few studies have examined the effect of wearing ETMs on physiological and hematological parameters in different sports. AIMS: The present study aimed to investigate the impact of ETM use in athletes on several hematological and physiological indicators among cyclists, runners, and swimmers. METHODS: The impact of wearing an ETM on lung function (LF), aerobic capacity (AC), and hematological levels in male university-level athletes (cyclists, runners, and swimmers) was investigated using an experimental approach. The participants (N = 44) were divided into (i) an experimental group wearing ETMs (n = 22; aged 21.24 ± 0.14 years old) and (ii) a control group not wearing ETMs (n = 22; aged 21.35 ± 0.19 years old). Both groups underwent 8 weeks of high-intensity cycle ergometer interval training. Pre- and post-training tests included the above-mentioned physiological and hematological parameters. RESULTS: Except for FEV1, FEV1/FVC, VT1, and MHR in the control group and FEV1/FVC and HRM in the experimental group, all variables were significantly improved after the 8-week cycle ergometer HIIT program. Significant benefits in favor of the experimental group were noted in terms of changes in FVC, FEV1, VO2max, VT1, PO to VT, VT2, and PO to VT2. CONCLUSIONS: The eight-week ETM-assisted HIIT program improved cardiorespiratory fitness and hematological variables in all participants. Future research would be useful to further investigate the physiological changes resulting from ETM-assisted HIIT programs.


Assuntos
Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade , Humanos , Masculino , Adulto Jovem , Adulto , Aptidão Cardiorrespiratória/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Universidades , Atletas , Pulmão
7.
Vet Immunol Immunopathol ; 250: 110456, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35728348

RESUMO

Opportunities to include Cetancodontamorpha in the study of the evolution of the immune system in the clades of Artiodactylamorpha, Ruminantiamorpha, Suinamorpha, and Camelidamorpha have increased with the use of the bottlenose dolphin, Tursiops truncatus, as a sentinel species to study the effects of environmental pollutants on the health of marine mammals. Efforts are currently underway to increase the number reagents needed for detailed studies. Thus far, screening of monoclonal antibodies (mAbs) made to leukocyte differentiation molecules (LDM) and the major histocompatibility (MHC) class I and class II molecules in Ruminantiamorpha have yielded some mAbs that recognize conserved epitopes expressed on orthologues in the bottlenose dolphin. More direct approaches are in progress to identify additional mAbs to bottlenose LDM and cytokines. As reported here, both direct and indirect approaches were used to identify mAbs specific for cytokines useful in monitoring the effects of environmental pollutants on the immune system. Immunization of mice with expressed bottlenose dolphin cytokines yielded mAbs specific for IFN-γ, TNF-α, IL-6, IL-8, IL-10, and IL-17A. Screening of previously developed mAbs used in livestock immunology research revealed mAbs developed against ovine IFN-γ and bovine IL-17 and IL-1ß recognize conserved epitopes in bottlenose dolphin orthologues. The mAbs identified in the present study expand the reagents available to study the function of the immune system in bottlenose dolphins and cattle.


Assuntos
Golfinho Nariz-de-Garrafa , Poluentes Ambientais , Animais , Anticorpos Monoclonais , Bovinos , Citocinas , Epitopos , Interferon gama , Interleucina-10 , Interleucina-17 , Interleucina-6 , Interleucina-8 , Camundongos , Ovinos , Carneiro Doméstico , Fator de Necrose Tumoral alfa
8.
Front Vet Sci ; 9: 878347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35591875

RESUMO

Progress in the study of the immune response to pathogens and candidate vaccines has been impeded by limitations in the methods to study the functional activity of T-cell subsets proliferating in response to antigens processed and presented by antigen presenting cells (APC). As described in this review, during our studies of the bovine immune response to a candidate peptide-based vaccine and candidate rel deletion mutants in Mycobacterium avium paratuberculosis (Map) and Mycbacterium bovis (BCG), we developed methods to study the primary and recall CD4 and CD8 T-cell responses using an ex vivo platform. An assay was developed to study intracellular killing of bacteria mediated by CD8 T cells using quantitative PCR to distinguish live bacteria from dead bacteria in a mixed population of live and dead bacteria. Through use of these assays, we were able to demonstrate vaccination with live rel Map and BCG deletion mutants and a Map peptide-based vaccine elicit development of CD8 cytotoxic T cells with the ability to kill intracellular bacteria using the perforin-granzyme B pathway. We also demonstrated tri-directional signaling between CD4 and CD8 T cells and antigen-primed APC is essential for eliciting CD8 cytotoxic T cells. Herein, we describe development of the assays and review progress made through their use in the study of the immune response to mycobacterial pathogens and candidate vaccines. The methods obviate some of the major difficulties encountered in characterizing the cell-mediated immune response to pathogens and development of attenuated and peptide-based vaccines.

9.
ISA Trans ; 129(Pt A): 193-205, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35039150

RESUMO

This paper introduces an integrated path tracking control strategy for autonomous vehicles. The proposed control strategy is based on a multi-input multi-output linear model predictive control (LMPC) with a fuzzy logic switching system. The designed MPC is based on Laguerre networks. The main target of the designed MPC is to produce the optimal control signals of the steering angle and the angular velocity while considering the physical constraints of the control signals and the measurements noise. Since the vehicle model is highly nonlinear and is operated over a wide range of operating points, different linearized models are obtained. The controller parameters for each linear model are designed and tuned. The gab metric analysis is used to select a number of these models to simplify the design of the proposed controller. Then, these models are combined using a fuzzy logic controller to switch between them. To test the proposed controller performance, different paths are generated using path planning algorithms. These paths simulate different vehicle maneuvers scenarios. The simulation results show that the designed tracking controller has a tracking performance on different designed paths better than that of a Linear quadratic gaussian (LQG) tracking controller, discussed in this paper.

10.
Vaccines (Basel) ; 9(10)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34696193

RESUMO

Lack of understanding of the immune response to mycobacterial pathogens has impeded progress in development of vaccines. Infection leads to development of an immune response that controls infection but is unable to eliminate the pathogen, resulting in a persistent infection. Although this puzzle remains to be solved, progress has been made using cattle as a model species to study the immune response to a prototypic mycobacterium, Mycobacterium a. paratuberculosis (Map). As chronicled in the review, incremental advances in characterizing the immune response to mycobacteria during the last 30 years with increases in information on the evolution of mycobacteria and relA, a gene regulating the stringent response, have brought us closer to an answer. We provide a brief overview of how mycobacterial pathogens were introduced into cattle during the transition of humankind to nomadic pastoralists who domesticated animals for food and farming. We summarize what is known about speciation of mycobacteria since the discovery of Mybacterium tuberculsis Mtb, M. bovis Mbv, and Map as zoonotic pathogens and discuss the challenges inherent in the development of vaccines to mycobacteria. We then describe how cattle were used to characterize the immune response to a prototypic mycobacterial pathogen and development of novel candidate vaccines.

11.
Vet Sci ; 8(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207122

RESUMO

The apicomplexan hemoparasite, Theileria parva, causes East Coast fever (ECF), a frequently fatal disease of African cattle. Vaccine development has been impeded by incomplete understanding of protective immunity following natural exposure or the infection and treatment method (ITM) of immunization. This is attributable to a paucity of methods to characterize the memory T-cell repertoire following infection. To overcome this impediment, assays developed to study the immune response to other intracellular pathogens were adapted for use in studies with T. parva to enable definition of the phenotype and function of effector T cells in T. parva-immune cattle, facilitating vaccine development. As reported herein, stimulation of peripheral blood mononuclear cells (PBMC) from ITM-immunized steers with irradiated, autologous, T. parva-infected cell lines elicited a proliferative recall response comprised of CD45R0+/CCR7- CD4+ and CD8+ T cells. Subsequent co-incubation of stimulated cultures with infected cells demonstrated the presence of cytotoxic T cells (CTLs) with the ability to kill infected cells. Comparison of CTL activity in cultures depleted of CD4+ or CD8+ T cells demonstrated CTL activity was primarily attributed to CD8+ T cells. Importantly, stimulation of PBMC from vaccinated steers always elicited proliferation of CD4+ and CD8+ T cells. This was the first important observation obtained from the use of the assay described herein.

12.
ACS Appl Bio Mater ; 4(8): 6381-6393, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35006907

RESUMO

Engineering an endothelium-mimetic surface has been one of long-lasting topics to develop ideal cardiovascular devices. The aim of the study was to investigate the potential use of a model of lipid bilayers that not only come from membranes extracted from endothelial cells (ECs) but also embedded with a type of organoselenium lipid enabling it to catalyze the generation of nitric oxide (NO). Herein, the titanium-cloaking in lipid bilayers extracted from ECs was prepared to propose a promising idea for the development of endovascular implants. For this purpose, we synthesized and characterized a lipidic molecule containing selenium and verified enough catalytic activity for the NO generation in the presence of S-nitrosothiols (RSNO) as endogenous NO precursors. We demonstrated the fabrication process of tethered lipid bilayers, from membrane extraction to vesicle fusion, and validated the successful formation of the layer and the catalyst insertion. The resulting bilayer presented endothelium-similar properties including the NO generation and cellular interactions. The catalyst inserted into the bilayer provided an unexampled result in the release period and kinetics of NO, likely similar to the native endothelial system. Using three different cells including EC, smooth muscle cell (SMC), and macrophage, it was demonstrated that the membrane responds selectively to each cell in the manner of promotive, suppressive, and nonimmunoreactive, respectively. Taken together, the fundamental study on obtained results not only provides understanding of the kinetics of designed NO catalyst and cellular interactions of reassembled membranes but also suggests very useful data on rational design and development of many vascular implantable devices, even expandable toward to nonvascular biointerfacing devices.


Assuntos
Células Endoteliais , Óxido Nítrico , Bicamadas Lipídicas/metabolismo , Miócitos de Músculo Liso/metabolismo , Óxido Nítrico/metabolismo , Titânio/metabolismo
13.
Tuberculosis (Edinb) ; 120: 101904, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32090858

RESUMO

Studies with Mycobacterium avium subsp. paratuberculosis (Map) in cattle revealed deletion of relA, a global regulator gene, abrogated ability of the mutant to establish a persistent infection, attributed to development of an immune response that cleared infection. Analysis of the recall response demonstrated presence of CD8 cytotoxic T cells that kill intracellular bacteria. Replication of the primary response demonstrated the CTL response could be elicited with the ΔMap/relA mutant or the target of the immune response, a 35 kD membrane protein. Follow up comparative studies with Mycobacterium bovis bacillus Calmette-Guérin (BCG) and a BCG relA (ΔBCG/relA) deletion mutant revealed deletion of relA enhanced the CTL response compared to BCG. Analysis of the cytokine profile of cells proliferating in response to stimulation with BCG or BCG/relA showed increased expression of IFN-γ, TNF-α, and IL-17 by cells stimulated with ΔBCG/relA in comparison with BCG. The proliferative and CTL responses were markedly reduced in response to stimulation with heat killed BCG or ΔBCG/relA. Intracellular bacterial killing was mediated through the perforin, granzyme B (GnzB), and the granulysin pathway. The data indicate relA is the Achilles' heel for pathogenic mycobacteria and deletion may be key to improving efficacy of attenuated vaccines for mycobacterial pathogens.


Assuntos
Proteínas de Bactérias/genética , Ligases/genética , Mycobacterium avium subsp. paratuberculosis/genética , Mycobacterium bovis/genética , Deleção de Sequência , Animais , Proteínas de Bactérias/metabolismo , Bovinos , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Granzimas/metabolismo , Interações Hospedeiro-Patógeno , Ligases/metabolismo , Ativação Linfocitária , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Masculino , Viabilidade Microbiana , Mycobacterium avium subsp. paratuberculosis/imunologia , Mycobacterium avium subsp. paratuberculosis/metabolismo , Mycobacterium bovis/metabolismo , Mycobacterium bovis/patogenicidade , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/microbiologia
14.
Vaccine ; 38(8): 2016-2025, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31902643

RESUMO

Studies in cattle show CD8 cytotoxic T cells (CTL), with the ability to kill intracellular bacteria, develop following stimulation of monocyte-depleted peripheral blood mononuclear cells (mdPBMC) with antigen presenting cells (APC, i.e. conventional dendritic cells [cDC] and monocyte-derived DC [MoDC]) pulsed with MMP, a membrane protein from Mycobacterium avium subsp. paratuberculosis (Map) encoded by MAP2121c. CTL activity was diminished if CD4 T cells were depleted from mdPBMC before antigen (Ag) presentation by APC, suggesting simultaneous cognate recognition of MMP epitopes presented by MHC I and MHC II molecules to CD4 and CD8 T cells is essential for development of CTL activity. To explore this possibility, studies were conducted with mdPBMC cultures in the presence of monoclonal antibodies (mAbs) specific for MHC class I and MHC class II molecules. The CTL response of mdPBMC to MMP-pulsed APC was completely blocked in the presence of mAbs to both MHC I and II molecules and also blocked in the presence of mAbs to either MHC I or MHC II alone. The results demonstrate simultaneous cognate recognition of Ag by CD4 and CD8 T cells is essential for delivery of CD4 T cell help to CD8 T cells to elicit development of CTL.


Assuntos
Epitopos/imunologia , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/prevenção & controle , Linfócitos T Citotóxicos/imunologia , Vacinas contra a Tuberculose/imunologia , Animais , Apresentação de Antígeno , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Bovinos , Células Cultivadas , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Leucócitos Mononucleares/imunologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Vacinas de Subunidades Antigênicas/imunologia
15.
ISA Trans ; 102: 251-263, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31813559

RESUMO

This paper introduces a discrete-time L1 adaptive controller design for collective pitch control for variable speed variable pitch wind turbines. In this control algorithm, the blades' pitch angles are regulated to manipulate the generator speed and generated power during high speeds wind airflow. The main merits of the proposed controller are its robustness against the wind turbine model uncertainties, guaranteeing the closed loop system stability and performance, and applicability during implementation in real life. Commonly used industrial gain-scheduled PI controller is used to be compared with the proposed controller. The proposed scheme is simulated using a 5-MW offshore turbine model and the obtained results illustrates the superior performance of the proposed controller. Further, a reduced scale wind turbine emulator is used to provide hardware in the loop to test the implementation of the proposed controller. The controller is implemented using laboratory equipment to demonstrate the feasibility of the controller for real time applications. The obtained experimental results validate the closed loop system performance enhancement due to replacing the traditional PI controller with the proposed design.

16.
Vet Surg ; 49 Suppl 1: O28-O37, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31222769

RESUMO

OBJECTIVE: To evaluate the feasibility of stem cell isolation from falciform fat harvested via laparoscopic morcellation. STUDY DESIGN: Pilot study. ANIMALS: Eleven client-owned dogs. METHODS: Falciform was harvested traditionally via laparotomy and laparoscopically via tissue morcellation. Harvested tissue was processed with a commercially available adipose tissue dissociation kit to obtain a stromal vascular fraction (SVF). Cells were subsequently labeled for CD90, CD45, and CD44 cell surface antigens by using magnetic-activated cell sorting (MACS) and fluorescence-activated cell sorting flow cytometry. CD90+ cells were quantitated, and their viability was assessed with a hemocytometer and a trypan blue exclusion test of cell viability. RESULTS: No perioperative complications occurred in dogs undergoing laparoscopic morcellation. Laparoscopically and traditionally harvested samples yielded an average of 0.39 (±0.1) × 106 and 0.33 (±0.1) × 106 CD90+ cells, respectively, per 10 million SVF cells. CD90+ cell viability after MACS was 89% (±11%) for morcellated and 86% (±7%) for traditionally harvested samples. Neither CD90+ cell quantity nor viability was different between samples obtained via traditional laparotomy vs laparoscopic morcellation (P = .38 and P = .63, respectively). Populations of CD90+ cells isolated with each harvest technique had similar CD44 and CD45 expression profiles. CONCLUSION: Viable populations of CD90+ cells with similar CD44/CD45 expression profiles were isolated from laparoscopically morcellated and traditionally harvested falciform tissue. No appreciable morbidity was associated with laparoscopic falciform morcellation. CLINICAL SIGNIFICANCE: Laparoscopic morcellation is a safe and effective minimally invasive approach to falciform tissue harvest for adipose-derived mesenchymal stem cell isolation.


Assuntos
Tecido Adiposo/citologia , Cães/anatomia & histologia , Laparoscopia/veterinária , Células-Tronco Mesenquimais/citologia , Coleta de Tecidos e Órgãos/veterinária , Animais , Células Cultivadas , Cães/cirurgia , Citometria de Fluxo , Humanos , Laparoscopia/métodos , Células-Tronco Mesenquimais/fisiologia , Morcelação , Projetos Piloto , Coleta de Tecidos e Órgãos/métodos
17.
Vet Immunol Immunopathol ; 211: 1-5, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31084887

RESUMO

Previous studies on the immune system of water buffalo (Bubalus bubalis) using cross-reactive monoclonal antibodies (mAbs) revealed significant similarities and differences to the bovine immune system. Herein, we extend these studies and document the pattern of expression of CD14, CD16, CD163 and CD172a on buffalo leukocytes using a set of cross-reactive mAbs that are known to recognize conserved epitopes within orthologous molecules in cattle, sheep and goats. Buffalo leukocytes were isolated and subjected to mAb labelling for flow cytometry. Single color flow cytometry confirmed mAbs recognition of buffalo orthologues of CD14, CD16, CD163 and CD172a, and revealed consistent patterns of expression similar to that reported in other ruminants. Multicolor flow cytometry revealed that buffalo CD14+ monocytes uniquely co-express CD16, CD163 and CD172a, whereas buffalo granulocytes co-express CD16 and CD172a. This study expands mAbs available to define and study the buffalo monocytes, and also extends information available on the unique features of the buffalo immune system.


Assuntos
Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/imunologia , Búfalos/imunologia , Leucócitos/imunologia , Receptores de Lipopolissacarídeos/imunologia , Receptores de Superfície Celular/imunologia , Receptores de IgG/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos de Diferenciação/imunologia , Citometria de Fluxo/veterinária , Granulócitos/imunologia , Monócitos/imunologia
18.
Vaccine ; 37(21): 2783-2790, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31003915

RESUMO

Recent efforts to develop a live attenuated vaccine against Mycobacterium avium subsp. paratuberculosis (Map), the causative agent of Johne's disease (JD), revealed relA is important in Map virulence. Deletion of the relA gene impairs the ability of Map to establish a persistent infection. Analysis of the basis for this observation revealed infection with a relA deletion mutant (ΔrelA) elicits development of cytotoxic CD8 T cells (CTL) with the ability to kill intracellular bacteria. Further analysis of the recall response elicited by ΔrelA vaccination showed a 35 kDa membrane peptide (MMP) is one of the targets of the immune response, suggesting it might be possible to develop a peptide-based vaccine based on MMP. To explore this possibility, ex vivo vaccination studies were conducted with MMP alone and incorporated into a nanoparticle (NP) vector comprised of poly (D, L-lactide-co-glycolide) and monophosphoryl lipid A (PLGA/MPLA). As reported, ex vivo vaccination studies showed CD8 CTL were elicited with classic and monocyte derived dendritic cells (cDC and MoDC) pulsed with MMP alone and incorporated into a PGLA/MPLA vector. Incorporation of MMP into a NP vector enhanced the ability of CD8 CTL to kill intracellular bacteria. The findings indicate incorporation of MMP into a PGLA/MPLA nanoparticle vector is one of the possible ways to develop a MMP based vaccine for Johne's disease.


Assuntos
Mycobacterium avium subsp. paratuberculosis/imunologia , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Nanopartículas/química , Peptídeos/química , Peptídeos/imunologia , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/uso terapêutico , Linfócitos T CD8-Positivos/metabolismo , Bovinos , Citometria de Fluxo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Linfócitos T Citotóxicos/metabolismo
19.
Front Immunol ; 10: 2859, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921129

RESUMO

Studies focused on development of an attenuated vaccine against Mycobacterium avium subsp. paratuberculosis (Map), the causative agent of paratuberculosis (Ptb) in cattle and other species, revealed that deletion of relA, a global gene regulator, abrogates the ability of Map to establish a persistent infection. In the absence of relA, cattle develop CD8 cytotoxic T cells (CTL) with the ability to kill intracellular bacteria. Analysis of the recall response to a relA mutant, Map/ΔrelA, with cells from a vaccinated steer demonstrated that a 35-kDa membrane peptide (MMP) is one of the targets of the response. This observation suggested that it might be possible to develop a peptide-based vaccine. As reported here, the gene encoding the hypothetical MMP ORF, MAP2121c, was modified for expression in mammalian cells as a first step in developing an expression cassette for incorporation into a mammalian expression vector. The modified sequence of MMP, tPA-MMP, was mutated to generate two additional sequences for the study, one with substitutions to replace five potential residues that could be glycosylated, tPA-MMP-5mut, and one with substitutions to replace the first two potential residues that could be glycosylated, tPA-MMP-2mut. The sequences were placed in an expression cassette to produce peptides for analysis. An ex vivo platform was used with flow cytometry and a bacterium viability assay to determine if modifications in the gene encoding MMP for expression in mammalian cells altered its capacity to elicit development of CD8 CTL, essential for its use in a peptide-based vaccine. Monocyte-depleted PBMC (mdPBMC) were stimulated with antigen-presenting cells (APC) pulsed with different MMP constructs. CD4 and CD8 T cells proliferated in response to stimulation with MMP (control) expressed in Escherichia coli (eMMP), tPA-MMP, and tPA-MMP-2mut. CD8 T cells retained the capacity to kill intracellular bacteria. The tPA-MMP-5mut failed to elicit a proliferative response and was not included in further studies. The data show that the expression cassettes containing MMP and MMP-2mut can be used to screen and select a mammalian expression vector for the development of an efficacious peptide-based vaccine against Ptb.


Assuntos
Proteínas de Bactérias , Vacinas Bacterianas , Linfócitos T CD8-Positivos/imunologia , Doenças dos Bovinos , Proteínas de Membrana , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Linfócitos T CD8-Positivos/patologia , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/prevenção & controle , Células HEK293 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Mycobacterium avium subsp. paratuberculosis/genética , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/genética , Paratuberculose/imunologia , Paratuberculose/prevenção & controle , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
20.
Adv Exp Med Biol ; 1077: 415-420, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30357701

RESUMO

Biomedical devices have come a long way since they were first introduced as a medically interventional methodology in treating various types of diseases. Different techniques were employed to make the devices more biocompatible and promote tissue repair; such as chemical surface modifications, using novel materials as the bulk of a device, physical topological manipulations and so forth. One of the strategies that recently gained a lot of attention is the use of tissue-inspired biomaterials that are coated on the surface of biomedical devices via different coating techniques, such as the use of extracellular matrix (ECM) coatings, extracted cell membrane coatings, and so on. In this chapter, we will give a general overview of the different types of tissue-inspired coatings along with a summary of recent studies reported in this scientific arena.


Assuntos
Materiais Revestidos Biocompatíveis , Matriz Extracelular , Medicina Regenerativa , Humanos , Propriedades de Superfície
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