Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 23
Filter
1.
Article in English | MEDLINE | ID: mdl-38063543

ABSTRACT

There are a multitude of health benefits gained from regular physical activity (PA). Currently, PA advice implementation from NHS nurses is inadequate despite their ever-increasing role in lifestyle and preventive medicine. By assessing their knowledge of current PA guidance, this study proposed to investigate the issues with regular PA advice being given and expand upon nurses' proposed barriers and solutions. A qualitative approach using semi structured interviews was undertaken between March and August 2023 involving 13 NHS nurses. Thematic analysis was undertaken using Braun and Clarke's six step approach. Four themes and fifteen subthemes emerged as barriers and solutions in delivering PA advice. Intrinsic barriers included a lack of nurse knowledge on the topic and PA being seen as an afterthought. Extrinsic barriers included time pressures and a lack of staff engagement. Solutions involved increasing staff awareness of guidelines through teaching, policy, encouraging staff to be active and optimising PA advice delivery through a piecemeal approach and utilising online and visual resources. This study displayed an insight into nurses' thoughts on their consultations with patients regarding PA, and proposed several barriers and solutions. Further work is needed to improve nurses' PA knowledge and to assess the proposed strategies to improve its delivery.


Subject(s)
Clinical Competence , Exercise , Humans , Qualitative Research , Referral and Consultation , United Kingdom
2.
J Sci Med Sport ; 26(10): 539-544, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37718192

ABSTRACT

OBJECTIVES: To quantify the incidence of concussion and compare between playing levels in male rugby league. DESIGN: Retrospective cohort. METHODS: Between 2016 and 2022, medically diagnosed concussions in Super League, Championship, and Academy competitions were reported to the Rugby Football League via club medical staff. Anonymised data were analysed using generalised linear mixed-effects models by season, month, and between competitions. RESULTS: Overall, 1403 concussions were identified from 104,209 player-match hours. Concussion incidence for Super League, Championship, and Academy was 15.5, 10.5, and 14.3 per 1000 player-match hours, respectively. Championship concussion incidence was significantly lower than the Super League (p < 0.001) and Academy (p < 0.001). No significant differences were identified between years for Super League (range: 13.3 to 18.8 per 1000 player-match hours) and Championship (range: 8.4 to 12.1 per 1000 player-match hours). In Academy (range: 9.6 to 20.5 per 1000 player-match hours), concussion incidence was significantly greater in 2021 compared to earlier years (2016, p = 0.01 and 2017, p = 0.03). No significant differences were identified between months for any competition. CONCLUSIONS: The incidence of concussion is greater in Super League and Academy compared to the Championship. Academy concussion incidence has increased over time. Different factors between and within competitions, such as changes to medical standards and knowledge, could have influenced the identification and diagnosis of concussion.


Subject(s)
Athletic Injuries , Brain Concussion , Humans , Male , Athletic Injuries/diagnosis , Incidence , Retrospective Studies , Rugby , Brain Concussion/diagnosis
4.
BMC Med Educ ; 23(1): 179, 2023 Mar 23.
Article in English | MEDLINE | ID: mdl-36959591

ABSTRACT

BACKGROUND: Sport and Exercise Medicine (SEM) is a growing speciality in the United Kingdom (UK). This growth has not been replicated in SEM teaching at an undergraduate level and SEM-related topics in schools of medicine in the UK are under-represented. As SEM continues to develop as a specialty it is important to consider how it is embedded at all levels of training. The aim of this project was to establish a consensus on SEM-related skills and knowledge relevant for undergraduate medical students in the UK, ultimately creating a curriculum of learning objectives (LOs). METHODS: A modified Delphi survey was utilised to seek consensus on LOs suitable for incorporation into UK medical school curricula. An expert panel with adequate knowledge in the field was recruited. The initial curriculum was created by the research team using already established postgraduate SEM curricula. All learning objectives were sent to the expert panel for opinions in phases. Levels of agreement and comments made by the expert panel were reviewed after each phase until a consensus on each learning objective was made. RESULTS: The expert panel was made up of 45 individuals, with 35 also completing phase 2 (78% retention rate). The initial curriculum contained 58 learning objectives separated into 9 themes. In phase 1 31% (18/58) were accepted outright, 48% (28/58) were altered and 19% (11/58) were rejected. Two additional learning objectives were added. Of the 49 LOs included in phase 2, 98% (48/49) were accepted. The final curriculum was made up of 9 sub-themes and 48 LOs. CONCLUSION: Sport and Exercise Medicine is a broad ranging and rapidly growing speciality. It is important to establish SEM education in all levels of medical education, including undergraduate level. This is the first published version of a Delphi SEM curriculum for undergraduate medical teaching.


Subject(s)
Education, Medical, Undergraduate , Medicine , Humans , Delphi Technique , Curriculum , Learning , United Kingdom
5.
Materials (Basel) ; 13(24)2020 Dec 12.
Article in English | MEDLINE | ID: mdl-33322695

ABSTRACT

The transient nature of the internal pore structure of particulate wall flow filters, caused by the continuous deposition of particulate matter, makes studying their flow and filtration characteristics challenging. In this article we present a new methodology and first experimental demonstration of time resolved in-situ synchrotron micro X-ray computed tomography (micro-CT) to study aerosol filtration. We directly imaged in 4D (3D plus time) pore scale deposits of TiO2 nanoparticles (nominal mean primary diameter of 25 nm) with a pixel resolution of 1.6 µm. We obtained 3D tomograms at a rate of ∼1 per minute. The combined spatial and temporal resolution allows us to observe pore blocking and filling phenomena as they occur in the filter's pore space. We quantified the reduction in filter porosity over time, from an initial porosity of 0.60 to a final porosity of 0.56 after 20 min. Furthermore, the penetration depth of particulate deposits and filtration rate was quantified. This novel image-based method offers valuable and statistically relevant insights into how the pore structure and function evolves during particulate filtration. Our data set will allow validation of simulations of automotive wall flow filters. Evolutions of this experimental design have potential for the study of a wide range of dry aerosol filters and could be directly applied to catalysed automotive wall flow filters.

6.
Vaccine ; 38(13): 2859-2869, 2020 03 17.
Article in English | MEDLINE | ID: mdl-32089463

ABSTRACT

To examine the link between meningococcal C (MenC) vaccine size and immunogenic response, a panel of MenC glycoconjugate vaccines were prepared differing in chain length, molar mass and hydrodynamic volume. The preparations consisted of different lengths of MenC polysaccharide (PS) covalently linked to monomeric purified tetanus toxoid (TT) carrier protein using the coupling reagent ethylcarbodiimide hydrochloride (EDC). Size exclusion chromatography with multi-angle light scattering (SEC-MALS) and viscometry analysis confirmed that the panel of MenC-TT conjugates spanned masses of 191,500 to 2,348,000 g/mol, and hydrodynamic radii ranging from 12.1 to 47.9 nm. The two largest conjugates were elliptical in shape, whereas the two smallest conjugates were more spherical. The larger conjugates appeared to fit a model described by multiple TTs with cross-linked PS, typical of lattice-like networks described previously for TT conjugates, while the smaller conjugates were found to fit a monomeric or dimeric TT configuration. The effect of vaccine conjugate size on immune responses was determined using a two-dose murine immunization. The two larger panel vaccine conjugates produced higher anti-MenC IgG1 and IgG2b titres after the second dose. Larger vaccine conjugate size also stimulated greater T-cell proliferative responses in an in vitro recall assay, although cytokines indicative of a T-helper response were not measurable. In conclusion, larger MenC-TT conjugates up to 2,348,000 g/mol produced by EDC chemistry correlate with greater humoral and cellular murine immune responses. These observations suggest that conjugate size can be an important modulator of immune response.


Subject(s)
Carbodiimides , Immunogenicity, Vaccine , Meningococcal Vaccines/immunology , Neisseria meningitidis, Serogroup C , Tetanus Toxoid/immunology , Animals , Antibodies, Bacterial , Immunoconjugates/immunology , Mice , Neisseria meningitidis, Serogroup C/immunology , Polysaccharides, Bacterial/immunology , Vaccines, Combined , Vaccines, Conjugate
7.
Resuscitation ; 139: 57-64, 2019 06.
Article in English | MEDLINE | ID: mdl-30981883

ABSTRACT

BACKGROUND: Characteristics and outcomes of exercise-related out-of-hospital cardiac arrests (OHCA) are not well described in Australia. METHODS: This was a retrospective observational study of non-exercise-related aetiology and exercise-related OHCAs from the Victorian Ambulance Cardiac Arrest Registry between 2008 and 2016, including 12-month quality of life data from 2010 to 2016. Exercise-related OHCA was defined as taking place during or within 1 h of at least moderate intensity exercise. Descriptive statistics and adjusted logistic regression analyses were performed. RESULTS: During the study period there were 482 exercise-related and 33,358 non-exercise-related OHCAs. Jogging/running were the most frequent precipitating sports. The incidence rate of exercise-related OHCA was low (<1 per 100,000 person-years). Compared to non-exercise-related aetiology, exercise-related OHCAs were younger (mean 54 versus 70 years, p < 0.001) and more likely to present in an initial shockable rhythm (85% versus 18%, p < 0.001). Bystander CPR, and bystander or EMS defibrillation at any time, were more common among exercise-related arrests (93% versus 38%, p < 0.001 and 91% versus 24%, p < 0.001, respectively). A public access defibrillator was used in 24% of shockable exercise-related OHCAs compared with 4% of non-exercise-related OHCAs (p < 0.001). After adjustment for arrest characteristics, exercise-related OHCAs were more likely to survive to hospital discharge (50% versus 14%, p < 0.001; adjusted odds ratio [AOR] = 1.56, 95% confidence interval [CI] 1.25-1.96, p < 0.001) and survive to 12-months with good functional recovery (72% versus 62%, p = 0.012; AOR = 1.57, 95% CI 1.08-2.28, p = 0.018). CONCLUSIONS: Exercise-related OHCAs were associated with better short- and long-term prognoses compared to non-exercise-related OHCAs. The underlying factors associated with this survival benefit warrant further investigation.


Subject(s)
Exercise , Out-of-Hospital Cardiac Arrest/mortality , Adult , Aged , Cardiopulmonary Resuscitation/statistics & numerical data , Case-Control Studies , Defibrillators , Electric Countershock/statistics & numerical data , Female , Humans , Male , Middle Aged , Out-of-Hospital Cardiac Arrest/etiology , Out-of-Hospital Cardiac Arrest/therapy , Quality of Life , Registries , Retrospective Studies , Time-to-Treatment , Victoria
8.
Materials (Basel) ; 11(10)2018 Oct 19.
Article in English | MEDLINE | ID: mdl-30347641

ABSTRACT

Ice cream is a complex multi-phase colloidal soft-solid and its three-dimensional microstructure plays a critical role in determining the oral sensory experience or mouthfeel. Using in-line phase contrast synchrotron X-ray tomography, we capture the rapid evolution of the ice cream microstructure during heat shock conditions in situ and operando, on a time scale of minutes. The further evolution of the ice cream microstructure during storage and abuse was captured using ex situ tomography on a time scale of days. The morphology of the ice crystals and unfrozen matrix during these thermal cycles was quantified as an indicator for the texture and oral sensory perception. Our results reveal that the coarsening is due to both Ostwald ripening and physical agglomeration, enhancing our understanding of the microstructural evolution of ice cream during both manufacturing and storage. The microstructural evolution of this complex material was quantified, providing new insights into the behavior of soft-solids and semi-solids, including many foodstuffs, and invaluable data to both inform and validate models of their processing.

9.
Adv Sci (Weinh) ; 3(3): 1500332, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27610334

ABSTRACT

Tracking the dynamic morphology of active materials during operation of lithium batteries is essential for identifying causes of performance loss. Digital volume correlation (DVC) is applied to high-speed operando synchrotron X-ray computed tomography of a commercial Li/MnO2 primary battery during discharge. Real-time electrode material displacement is captured in 3D allowing degradation mechanisms such as delamination of the electrode from the current collector and electrode crack formation to be identified. Continuum DVC of consecutive images during discharge is used to quantify local displacements and strains in 3D throughout discharge, facilitating tracking of the progression of swelling due to lithiation within the electrode material in a commercial, spiral-wound battery during normal operation. Displacement of the rigid current collector and cell materials contribute to severe electrode detachment and crack formation during discharge, which is monitored by a separate DVC approach. Use of time-lapse X-ray computed tomography coupled with DVC is thus demonstrated as an effective diagnostic technique to identify causes of performance loss within commercial lithium batteries; this novel approach is expected to guide the development of more effective commercial cell designs.

10.
J Microsc ; 263(3): 280-92, 2016 09.
Article in English | MEDLINE | ID: mdl-26999804

ABSTRACT

Lithium-ion battery performance is intrinsically linked to electrode microstructure. Quantitative measurement of key structural parameters of lithium-ion battery electrode microstructures will enable optimization as well as motivate systematic numerical studies for the improvement of battery performance. With the rapid development of 3-D imaging techniques, quantitative assessment of 3-D microstructures from 2-D image sections by stereological methods appears outmoded; however, in spite of the proliferation of tomographic imaging techniques, it remains significantly easier to obtain two-dimensional (2-D) data sets. In this study, stereological prediction and three-dimensional (3-D) analysis techniques for quantitative assessment of key geometric parameters for characterizing battery electrode microstructures are examined and compared. Lithium-ion battery electrodes were imaged using synchrotron-based X-ray tomographic microscopy. For each electrode sample investigated, stereological analysis was performed on reconstructed 2-D image sections generated from tomographic imaging, whereas direct 3-D analysis was performed on reconstructed image volumes. The analysis showed that geometric parameter estimation using 2-D image sections is bound to be associated with ambiguity and that volume-based 3-D characterization of nonconvex, irregular and interconnected particles can be used to more accurately quantify spatially-dependent parameters, such as tortuosity and pore-phase connectivity.

11.
FASEB J ; 29(6): 2595-602, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25746794

ABSTRACT

There is an urgent unmet need for human tissue bioassays to predict cytokine storm responses to biologics. Current bioassays that detect cytokine storm responses in vitro rely on endothelial cells, usually from umbilical veins or cell lines, cocultured with freshly isolated peripheral blood mononuclear cells (PBMCs) from healthy adult volunteers. These assays therefore comprise cells from 2 separate donors and carry the disadvantage of mismatched tissues and lack the advantage of personalized medicine. Current assays also do not fully delineate mild (such as Campath) and severe (such as TGN1412) cytokine storm-inducing drugs. Here, we report a novel bioassay where endothelial cells grown from stem cells in the peripheral blood (blood outgrowth endothelial cells) and PBMCs from the same donor can be used to create an autologous coculture bioassay that responds by releasing a plethora of cytokines to authentic TGN1412 but only modestly to Campath and not to control antibodies such as Herceptin, Avastin, and Arzerra. This assay performed better than the traditional mixed donor assay in terms of cytokine release to TGN1412 and, thus, we suggest provides significant advancement and a definitive system by which biologics can be tested and paves the way for personalized medicine.


Subject(s)
Biological Products/pharmacology , Cytokines/metabolism , Endothelial Cells/drug effects , Leukocytes, Mononuclear/drug effects , Alemtuzumab , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal, Humanized/pharmacology , Bevacizumab , Biological Assay/methods , Cell Proliferation/drug effects , Coculture Techniques , Culture Media/pharmacology , Endothelial Cells/cytology , Endothelial Cells/metabolism , Enzyme-Linked Immunosorbent Assay , Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Interleukin-2/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/metabolism , Reproducibility of Results , Serum/chemistry , Trastuzumab , Tumor Necrosis Factor-alpha/metabolism
12.
Chem Commun (Camb) ; 51(2): 266-8, 2015.
Article in English | MEDLINE | ID: mdl-24898258

ABSTRACT

The electrodeposition of metallic lithium is a major cause of failure in lithium batteries. The 3D microstructure of electrodeposited lithium 'moss' in liquid electrolytes has been characterised at sub-micron resolution for the first time. Using synchrotron X-ray phase contrast imaging we distinguish mossy metallic lithium microstructures from high surface area lithium salt formations by their contrasting X-ray attenuation.


Subject(s)
Electroplating , Imaging, Three-Dimensional , Lithium/chemistry , Electroplating/methods , Imaging, Three-Dimensional/methods , Synchrotrons , X-Rays
13.
J Synchrotron Radiat ; 21(Pt 5): 1134-9, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25178003

ABSTRACT

A new technique combining in situ X-ray diffraction using synchrotron radiation and infrared thermal imaging is reported. The technique enables the application, generation and measurement of significant thermal gradients, and furthermore allows the direct spatial correlation of thermal and crystallographic measurements. The design and implementation of a novel furnace enabling the simultaneous thermal and X-ray measurements is described. The technique is expected to have wide applicability in material science and engineering; here it has been applied to the study of solid oxide fuel cells at high temperature.

14.
J Virol ; 88(20): 11955-64, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25100844

ABSTRACT

Inactivated polio vaccines, which have been used in many countries for more than 50 years, are produced by treating live poliovirus (PV) with formaldehyde. However, the molecular mechanisms underlying virus inactivation are not well understood. Infection by PV is initiated by virus binding to specific cell receptors, which results in viral particles undergoing sequential conformational changes that generate altered structural forms (135S and 80S particles) and leads to virus cell entry. We have analyzed the ability of inactivated PV to bind to the human poliovirus receptor (hPVR) using various techniques such as ultracentrifugation, fluorescence-activated cell sorting flow cytometry and real-time reverse transcription-PCR (RT-PCR). The results showed that although retaining the ability to bind to hPVR, inactivated PV bound less efficiently in comparison to live PV. We also found that inactivated PV showed resistance to structural conversion in vitro, as judged by measuring changes in antigenicity, the ability to bind to hPVR, and viral RNA release at high temperature. Furthermore, viral RNA from inactivated PV was shown to be modified, since cDNA yields obtained by RT-PCR amplification were severely reduced and no infectious virus was recovered after RNA transfection into susceptible cells. Importance: This study represents a novel insight into the molecular mechanisms responsible for poliovirus inactivation. We show that inactivation with formaldehyde has an effect on early steps of viral replication as it reduces the ability of PV to bind to hPVR, decreases the sensitivity of PV to convert to 135S particles, and abolishes the infectivity of its viral RNA. These changes are likely responsible for the loss of infectivity shown by PV following inactivation. Techniques used in this study represent new approaches for the characterization of inactivated PV products and could be useful in developing improved methods for the production and quality control testing of inactivated polio vaccines. Measuring the antigenicity, capsid stability, and RNA integrity of inactivated PV samples could help establishing the optimal balance between the loss of infectivity and the preservation of virus antigenicity during inactivation.


Subject(s)
Formaldehyde/pharmacology , Poliovirus/drug effects , Cell Line , Flow Cytometry , Humans , Poliovirus/genetics , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction , Receptors, Virus/drug effects , Reverse Transcriptase Polymerase Chain Reaction
16.
Br J Clin Pharmacol ; 76(2): 299-315, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23701319

ABSTRACT

AIM: To determine if cytokine release with a solid phase assay is predictive of adverse responses for a range of therapeutic mAbs. METHODS: Cytokine ELISAs and a multi-array system were used to compare responses generated by different therapeutic mAbs using a solid phase assay. Flow cytometry was employed to determine the cellular source of those cytokines. RESULTS: Only TGN1412 and muromonab-CD3 stimulated CD4+ T-cell mediated cytokine release characterized by significant (all P < 0.0001) IFNγ, TNFα, IL-2, IL-4, IL-5, IL-10, IL-12, IL-13, IL-17 and IL-22 release, comparable with T-cell mitogen. Significantly greater (P < 0.0001) IL-2 release with TGN1412 (2894-6051 pg ml⁻¹) compared with muromonab-CD3 (62-262 pg ml⁻¹) differentiated otherwise comparable cytokine responses. Likewise, TGN1412 stimulated significantly more (P = 0.0001) IL-2 producing CD4+ T-cells than muromonab-CD3 and induced Th1, Th2, Th17 and Th22 subsets that co-release this cytokine. Significant TNFα release was observed with bevacizumab (P = 0.0001), trastuzumab (P = 0.0031) and alemtuzumab (P = 0.0177), but no significant IL-2 release. TGN1412 and muromonab-CD3 caused pro-inflammatory cytokine release despite significantly (both P < 0.0001) increasing numbers of T-cells with a regulatory phenotype. CONCLUSIONS: The severity of the adverse response to TGN1412 compared with muromonab-CD3 and other therapeutic mAbs correlates with the level of IL-2 release.


Subject(s)
Antibodies, Monoclonal, Humanized/adverse effects , Antibodies, Monoclonal/adverse effects , Cytokines/immunology , Interleukin-2/immunology , Muromonab-CD3/adverse effects , Research Design/standards , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal, Humanized/immunology , Clinical Trials as Topic , Cytokines/drug effects , Drug-Related Side Effects and Adverse Reactions/prevention & control , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Humans , Muromonab-CD3/immunology , Risk Assessment
17.
J Immunol ; 189(12): 5831-40, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23150712

ABSTRACT

The unexpected outcome of the clinical trial of the superagonistic CD28 mAb TGN1412 (IgG4κ) continues to stimulate interest. We show that TGN1412 binds similarly to human and cynomolgus macaque FcγR, eliminating the possibility that differences in Fc-mediated interactions with FcγR contributed to the failure of preclinical testing in macaques to predict toxicity in humans. The influence of the Fc domain and C region structure on the in vitro functional activity of TGN1412 was investigated using F(ab')(2) and Fab fragments derived from TGN1412 recovered from the trial and recombinant TGN1412 subclass variants and mutants. Superagonistic activity, as measured by cytokine release and proliferation, was assessed by exposing PBMCs to immobilized mAbs/fragments or to aqueous mAbs/fragments in the presence of HUVEC monolayers. Removing the Fc generally curtailed or abolished PBMC activation. However, eliminating detectable FcγR-binding of the IgG4 by mutation (L235E) did not abrogate activity. Stabilizing the "wild-type" IgG4 hinge (S228P) enhanced activity without increasing FcγR binding, which could only partially be explained by inhibition of Fab arm-exchange. Subclass switching the IgG4 mAb to IgG1 decreased activity, whereas switching to IgG2 markedly increased activity. We conclude that the C region strongly influences in vitro CD28-mediated superagonistic signaling. Superagonism requires an intact Fc, as shown by the absence of activity of TGN1412 Fab and F(ab')(2) fragments, but, notably, appears to be relatively independent of FcγR-binding properties. We propose that the Fc, potentially through restricting flexibility, maintains a favorable V region conformation to allow superagonistic activity. These findings have important implications for Ab design strategies.


Subject(s)
Antibodies, Monoclonal, Humanized/metabolism , Antibodies, Monoclonal/physiology , Immunoglobulin Constant Regions/physiology , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal, Humanized/physiology , Binding Sites, Antibody/immunology , Cell Proliferation , Cells, Cultured , Clinical Trials, Phase I as Topic , Coculture Techniques , Cytokines/metabolism , Human Umbilical Vein Endothelial Cells , Humans , Immunoglobulin Constant Regions/chemistry , Immunoglobulin Constant Regions/metabolism , Immunoglobulin Fab Fragments/physiology , Immunoglobulin Fc Fragments/physiology , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Macaca fascicularis , Protein Binding/immunology , Receptors, IgG/metabolism , Receptors, IgG/physiology , Recombinant Proteins/metabolism
18.
J Immunol Methods ; 371(1-2): 134-42, 2011 Aug 31.
Article in English | MEDLINE | ID: mdl-21741383

ABSTRACT

Two methods for predicting the risk of pro-inflammatory clinical infusion reactions during monoclonal antibody therapy were evaluated. In the first, the antibody of interest is immobilised by air-drying onto 96-well plates prior to the addition of human peripheral blood mononuclear cells (PBMCs). In the second, the antibody is added in aqueous phase to a co-culture of human PBMCs and human endothelium-derived cells. In both methods the cells are incubated with the antibody to allow the accumulation of pro-inflammatory cytokines, quantified by enzyme-linked immunosorbent assay (ELISA). The antibodies associated with clinical infusion reactions, Herceptin, Campath-1H and TGN1412, gave the largest responses taking into account the data for all readouts (tumour necrosis factor-α, TNF, interleukin-6, IL-6, IL-8, IL-2 and cell proliferation) for both methods. Overall, the antibodies tested could be ranked as follows: Tysabri

Subject(s)
Antibodies, Monoclonal/adverse effects , Immunotherapy/adverse effects , Inflammation/etiology , Antibodies, Immobilized , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/therapeutic use , Cell Proliferation , Coculture Techniques , Cytokines/analysis , Cytokines/biosynthesis , Endothelial Cells/immunology , Enzyme-Linked Immunosorbent Assay/methods , Humans , Immunoassay/methods , Inflammation/immunology , Inflammation Mediators/analysis , Inflammation Mediators/metabolism , Infusions, Intravenous , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/pathology , Risk Factors
19.
Cytokine ; 55(1): 141-51, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21493088

ABSTRACT

The failure of preclinical testing to predict the severity of the cytokine storm experienced by the recipients of the superagonistic anti-CD28 monoclonal antibody (mAb) TGN1412 during its Phase 1 clinical trial prompted the development of new in vitro experimental approaches for mimicking in vivo cytokine release and lymphoproliferation. Peripheral blood mononuclear cells (PBMC) presented to TGN1412 immobilised on plastic has previously been shown to stimulate a pro-inflammatory cytokine response. The aim of the present study was to investigate a 'co-culture' model for the detection of TGN1412-like immunomodulatory activity in which TGN1412 was presented to PBMC in the presence of monolayers of endothelium-derived cells and other cell types, followed by measurement of cytokine levels in the culture supernatants and proliferation of PBMC. Culturing PBMC with TGN1412 over primary human umbilical vein endothelial cells (HUVEC) and HUVEC-derived cell lines retaining classic endothelial markers, but not cell lines of non-endothelial origin, mediated the specific release of IL-6, IL-8 and TNFα, and proliferation of PBMC. Low levels of IL-2 and IFNγ were also detected in supernatants with most donors of PBMC. An anti-CD28 mAb agonist, i.e., not a superagonist like TGN1412, did not stimulate cytokine release or proliferation of PBMC in co-cultures. In conclusion, co-culture experiments for TGN1412-specific cytokine release required cells of endothelial origin. However, the profile of released cytokines in co-cultures did not mirror that in the clinical trial participants or the responses from PBMC exposed to TGN1412 immobilised on plastic, suggesting that TGN1412 stimulation of PBMC can occur through more than one mechanism.


Subject(s)
Antibodies, Monoclonal/pharmacology , Endothelial Cells/cytology , Leukocytes, Mononuclear/cytology , Antibodies, Monoclonal, Humanized , Biomarkers/metabolism , Cell Proliferation/drug effects , Cells, Cultured , Coculture Techniques , Cytokines/biosynthesis , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Enzyme-Linked Immunosorbent Assay , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/metabolism , Humans , Immunohistochemistry , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Time Factors , Umbilical Veins/cytology
20.
J Immunol Methods ; 352(1-2): 1-12, 2010 Jan 31.
Article in English | MEDLINE | ID: mdl-19895813

ABSTRACT

TGN1412 is a "superagonistic" CD28 monoclonal antibody (IgG4) that caused serious adverse events at its first time in human clinical trial. In the present study, different in vitro methods for detecting and quantifying unwanted pro-inflammatory activity of therapeutic monoclonal antibodies (mAbs) such as TGN1412 are described. The antibody of interest is immobilised by wet-coating or air-drying onto polypropylene or polystyrene 96-well plates prior to the addition of human peripheral blood mononuclear cells (PBMCs). The cells are incubated for 16-24h with the immobilised antibody which allows the accumulation of pro-inflammatory cytokines, quantified by enzyme-linked immunoabsorbent assay (ELISA), in response to the antibody. Cytokine responses stimulated by TGN1412 immobilised by air-drying onto polypropylene and polystyrene plates were much larger than responses to TGN1412 wet-coated onto polypropylene and polystyrene plates, respectively. In additional experiments with other mAbs associated with clinical reactions, air-dried mAbs stimulated larger tumour necrosis factor-alpha (TNF) responses than antibodies added in aqueous phase. Also, TGN1412 air-dried onto plastic plates stimulated large proliferative responses of 3-day cultures of lymphocytes. It was concluded that immobilising mAbs by air-drying offers a useful in vitro method for detecting and quantifying pro-inflammatory activities of therapeutic mAbs.


Subject(s)
Antibodies, Monoclonal/pharmacology , CD28 Antigens/immunology , Drug Evaluation/methods , Enzyme-Linked Immunosorbent Assay , Leukocytes, Mononuclear/drug effects , Antibodies, Monoclonal, Humanized , Binding, Competitive , CD28 Antigens/metabolism , Cell Proliferation/drug effects , Cells, Cultured , Humans , Immunotherapy, Active , In Vitro Techniques , Leukocytes, Mononuclear/immunology , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , Recombinant Fusion Proteins/metabolism , Tumor Necrosis Factor-alpha/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...