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Featured researches published by Didier Locca.


Regenerative Medicine | 2009

Ficoll-Paque™ versus Lymphoprep™: a comparative study of two density gradient media for therapeutic bone marrow mononuclear cell preparations

Chia Yeo; Natalie Saunders; Didier Locca; Andy Flett; Melanie Preston; Pat Brookman; Barbara Davy; Anthony Mathur; Samir G. Agrawal

AIMS Contradictory outcomes from recent clinical trials investigating the transplantation of autologous bone marrow mononuclear cell (BM-MNC) fraction containing stem/progenitor cells to damaged myocardium, following acute myocardial infarction, may be, in part, due to the different cell isolation protocols used. We compared total BM-MNC numbers and its cellular subsets obtained following isolation using Ficoll-Paque and Lymphoprep - two different density gradient media used in the clinical trials. MATERIALS & METHODS Bone marrow samples were taken from patients entered into the REGENERATE-IHD clinical trial after 5 days of subcutaneous granulocyte colony-stimulating factor injections. Each sample was divided equally for BM-MNC isolation using Ficoll-Paque and Lymphoprep, keeping all other procedural steps constant. Isolated fractions were characterized for hematopoietic stem cells, endothelial progenitor cells, T lymphocytes, B lymphocytes and NK cells using cell surface markers CD34(+), CD133(+)VEGFR2(+), CD45(+)CD3(+), CD45(+)CD19(+) and CD45(+)CD16(+)CD56(+), respectively. There were no significant differences in the absolute numbers and percentage cell recovery of various mononuclear cell types recovered following separation using either density gradient media. Cell viability and the proportion of various cell phenotypes investigated were similar between the two media. They were also equally efficient in excluding unwanted red blood cells, granulocytes and platelets from the final cell products. CONCLUSION We demonstrated that the composition and quantity of cell types found within therapeutic BM-MNC preparations for use in clinical trials of cardiac stem cell transplantation are not influenced by the type of density gradient media used when comparing Ficoll-Paque and Lymphoprep.


European Heart Journal | 2015

Randomized trial of combination cytokine and adult autologous bone marrow progenitor cell administration in patients with non-ischaemic dilated cardiomyopathy: the REGENERATE-DCM clinical trial

Stephen Hamshere; Samer Arnous; Tawfiq Choudhury; Fizzah Choudry; Abdul Mozid; Chia Rou Yeo; Catherine Barrett; Natalie Saunders; Ankur Gulati; Charles Knight; Didier Locca; Ceri Davies; Martin R. Cowie; Sanjay Prasad; Mahesh Parmar; Samir G. Agrawal; Daniel A. Jones; John D Martin; William J. McKenna; Anthony Mathur

Aims The REGENERATE-DCM trial is the first phase II randomized, placebo-controlled trial aiming to assess if granulocyte colony-stimulating factor (G-CSF) administration with or without adjunctive intracoronary (IC) delivery of autologous bone marrow-derived cells (BMCs) improves global left ventricular (LV) function in patients with dilated cardiomyopathy (DCM) and significant cardiac dysfunction. Methods and results Sixty patients with DCM and left ventricular ejection fraction (LVEF) at referral of ≤45%, New York Heart Association (NYHA) classification ≥2 and no secondary cause for the cardiomyopathy were randomized equally into four groups: peripheral placebo (saline), peripheral G-CSF, peripheral G-CSF and IC serum, and peripheral G-CSF and IC BMC. All patients, except the peripheral placebo group, received 5 days of G-CSF. In the IC groups, this was followed by bone marrow harvest and IC infusion of cells or serum on Day 6. The primary endpoint was LVEF change from baseline to 3 months, determined by advanced cardiac imaging. At 3 months, peripheral G-CSF combined with IC BMC therapy was associated with a 5.37% point increase in LVEF (38.30% ± 12.97 from 32.93% ± 16.46 P = 0.0138), which was maintained to 1 year. This was associated with a decrease in NYHA classification, reduced NT-pro BNP, and improved exercise capacity and quality of life. No significant change in LVEF was seen in the remaining treatment groups. Conclusion This is the first randomized, placebo-controlled trial with a novel combination of G-CSF and IC cell therapy that demonstrates an improvement in cardiac function, symptoms, and biochemical parameters in patients with DCM.


European Heart Journal | 2016

A randomized double-blind control study of early intra-coronary autologous bone marrow cell infusion in acute myocardial infarction: the REGENERATE-AMI clinical trial

Fizzah Choudry; Stephen Hamshere; Natalie Saunders; Jessry Veerapen; Katrine Bavnbek; Charles Knight; Denis Pellerin; Didier Locca; Mark Westwood; Roby Rakhit; Tom Crake; Jens Kastrup; Mahesh Parmar; Samir G. Agrawal; Daniel A. Jones; John Martin; Anthony Mathur

Abstract Aims Clinical trials suggest that intracoronary delivery of autologous bone marrow-derived cells (BMCs) 1–7 days post-acute myocardial infarction (AMI) may improve left ventricular (LV) function. Earlier time points have not been evaluated. We sought to determine the effect of intracoronary autologous BMC on LV function when delivered within 24 h of successful reperfusion therapy. Methods and results A multi-centre phase II randomized, double-blind, and placebo-controlled trial. One hundred patients with anterior AMI and significant regional wall motion abnormality were randomized to receive either intracoronary infusion of BMC or placebo (1:1) within 24 h of successful primary percutaneous intervention (PPCI). The primary endpoint was the change in left ventricular ejection fraction (LVEF) between baseline and 1 year as determined by advanced cardiac imaging. At 1 year, although LVEF increased compared with baseline in both groups, the between-group difference favouring BMC was small (2.2%; 95% confidence interval, CI: −0.5 to 5.0; P = 0.10). However, there was a significantly greater myocardial salvage index in the BMC-treated group compared with placebo (0.1%; 95% CI: 0.0–0.20; P = 0.048). Major adverse events were rare in both treatment groups. Conclusion The early infusion of intracoronary BMC following PPCI for patients with AMI and regional wall motion abnormality leads to a small non-significant improvement in LVEF when compared with placebo; however, it may play an important role in infarct remodelling and myocardial salvage. Clinical trial registration Clinicaltrials.gov NCT00765453 and EudraCT 2007-002144-16.


Jacc-cardiovascular Interventions | 2010

New Universal Definition of Myocardial Infarction: Applicable After Complex Percutaneous Coronary Interventions?

Didier Locca; Chiara Bucciarelli-Ducci; Giuseppe Ferrante; Alessio La Manna; Niall G. Keenan; Agata Grasso; Francesca Del Furia; Sanjay Prasad; Juan Carlos Kaski; Dudley J. Pennell; Carlo Di Mario

OBJECTIVES This study aimed to characterize myocardial infarction after percutaneous coronary intervention (PCI) based on cardiac marker elevation as recommended by the new universal definition and on the detection of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR). It is also assessed whether baseline inflammatory biomarkers are higher in patients developing myocardial injury. BACKGROUND Cardiovascular magnetic resonance accurately assesses infarct size. Baseline C-reactive protein (CRP) and neopterin predict prognosis after stent implantation. METHODS Consecutive patients with baseline troponin (Tn) I within normal limits and no LGE in the target vessel underwent baseline and post-PCI CMR. The Tn-I was measured until 24 h after PCI. Serum high-sensitivity CRP and neopterin were assessed before coronary angiography. RESULTS Of 45 patients, 64 (53 to 72) years of age, 33% developed LGE with infarct size of 0.83 g (interquartile range: 0.32 to 1.30 g). A Tn-I elevation >99% upper reference limit (i.e., myocardial necrosis) (median Tn-I: 0.51 μg/l, interquartile range: 0.16 to 1.23) and Tn-I > 3× upper reference limit (i.e., type 4a myocardial infarction [MI]) occurred in 58% and 47% patients, respectively. LGE was undetectable in 42% and 43% of patients with periprocedural myocardial necrosis and type 4a MI, respectively. Agreement between LGE and type 4a MI was moderate (kappa = 0.45). The levels of CRP or neopterin did not significantly differ between patients with or without myocardial injury, detected by CMR or according to the new definition (p = NS). CONCLUSIONS This study reports the lack of substantial agreement between the new universal definition and CMR for the diagnosis of small-size periprocedural myocardial damage after complex PCI. Baseline levels of CRP or neopterin were not predictive for the development of periprocedural myocardial damage.


Regenerative Medicine | 2014

Safety and feasibility of intramyocardial versus intracoronary delivery of autologous cell therapy in advanced heart failure: the REGENERATE-IHD pilot study.

Abdul Mozid; Chia Yeo; Samer Arnous; Emmanuel Ako; Natalie Saunders; Didier Locca; Pat Brookman; R. Andrew Archbold; Martin T. Rothman; Peter Mills; Samir G. Agrawal; John Martin; Anthony Mathur

AIM This study presents an interim safety and feasibility analysis of the REGENERATE-IHD randomized controlled trial, which is examining the safety and efficacy of three different delivery routes of bone marrow-derived stem cells (BMSCs) in patients with ischemic heart failure. METHODS & RESULTS The first 58 patients recruited to the REGENERATE-IHD study are included in this interim analysis (pilot). Symptomatic patients with ischemic heart failure were randomized to receive subcutaneous granulocyte colony-stimulating factor or saline injections only; or subcutaneous granulocyte colony-stimulating factor injections followed by intracoronary or intramyocardial injections of BMSCs or serum (control). No significant differences were found in terms of safety and feasibility between the different delivery routes, with no significant difference in procedural complications or major adverse cardiac events. There was a signal towards improved heart failure symptoms in the patients treated with intramyocardial injection of mobilized BMSCs. CONCLUSION Peripheral mobilization of BMSCs with or without subsequent direct myocardial delivery appears safe and feasible in patients with chronic ischemic heart failure.


Atherosclerosis | 2009

Magnetic resonance of carotid artery ageing in healthy subjects.

Niall G. Keenan; Didier Locca; Anitha Varghese; Michael Roughton; Peter D. Gatehouse; James Hooper; David N. Firmin; Dudley J. Pennell

OBJECTIVE To assess how the arterial wall of the carotid artery changes with age in normal subjects by cardiovascular magnetic resonance (CMR). METHODS Carotid CMR was performed in 100 normal subjects (10 per sex per decade) who were free of atherosclerotic risk factors and carotid atherosclerosis. Using three-dimensional computer modeling, the volumes of the arterial wall, lumen, and the total vessel were calculated, and the wall/outer wall (W/OW) ratio was derived. RESULTS Wall volume and total vessel volume increased significantly with age in both sexes (p<0.006), and this was more marked in males. The W/OW ratio also increased significantly with age (p<0.001). Lumen volume increased significantly with age in males (p<0.001), but not in females (p=0.1). CONCLUSIONS In normal subjects, carotid wall volume increases with age. In men, this vessel wall volume increase is associated with significant remodeling of the lumen and outer wall. These data relating normal carotid findings with ageing are important for further CMR studies of early atherosclerosis.


European Journal of Heart Failure | 2017

An exploratory randomized control study of combination cytokine and adult autologous bone marrow progenitor cell administration in patients with ischaemic cardiomyopathy: the REGENERATE‐IHD clinical trial

Tawfiq Choudhury; Abdul Mozid; Steve Hamshere; Chia Yeo; Cyril Pellaton; Samer Arnous; Natalie Saunders; Pat Brookman; Ajay K. Jain; Didier Locca; Andrew Archbold; Charles Knight; Andrew Wragg; Ceri Davies; Peter Mills; Mahesh K. B. Parmar; Martin T. Rothman; Fizzah Choudry; D A Jones; Samir G. Agrawal; John Martin; Anthony Mathur

The effect of combined cytokine and cell therapy in ischaemic cardiomyopathy is unknown. Meta‐analyses suggest improved cardiac function with cell therapy. The optimal cell delivery route remains unclear. We investigated whether granulocyte colony‐stimulating factor (G‐CSF) alone or in combination with intracoronary (i.c.) or intramyocardial (i.m.) injection of autologous bone marrow‐derived cells (BMCs) improves cardiac function.


BMJ Open | 2014

A randomised double-blind control study of early intracoronary autologous bone marrow cell infusion in acute myocardial infarction (REGENERATE-AMI)

Stephen Hamshere; Tawfiq Choudhury; D A Jones; Didier Locca; Peter Mills; Martin T. Rothman; Charles Knight; Mahesh K. B. Parmar; Samir G. Agrawal; John Martin; Anthony Mathur

Introduction Acute myocardial infarction (AMI) remains a major cause of mortality and morbidity worldwide despite the latest therapeutic advances designed to decrease myocardial injury. Preclinical and emerging clinical evidence show that the intracoronary injection of autologous bone marrow mononuclear cells (BMCs) following AMI leads to improvement in left ventricular ejection function (LVEF). In this clinical trial we will for the first time assess the effect of early (<24 h) infusion of autologous BMCs following AMI on cardiac function. Methods and analysis REGENERATE-AMI is a double-blind, randomised, multicentre, placebo-controlled trial to determine whether early (<24 h) intracoronary infusion of BMCs improves LVEF after AMI. The study will enrol 100 patients presenting with an anterior AMI demonstrating anterior regional wall motion abnormality. Patients will be randomised to receive intracoronary infusion of BMCs or placebo (0.9% saline). Primary endpoint will be change in LVEF at 1 year compared to baseline, measured by cardiac MRI. Secondary endpoints at 6 months include the change in global LVEF relative to baseline measured by quantitative left ventriculography and echocardiography, as well as major adverse cardiac events which is also measured at 1 year. Ethics and dissemination The study will be performed in agreement with the Declaration of Helsinki and is approved by local ethics committee (NRES Committee London West London: 07/Q0603/76). Trial registration http://clincialtrials.gov (NCT00765453). The results of the trial will be published according to the CONSORT statement and will be presented at conferences and reported in peer-reviewed journals.


Journal of Magnetic Resonance Imaging | 2008

Comparison of 2D and multislab 3D magnetic resonance techniques for measuring carotid wall volumes

Niall G. Keenan; Agata Grasso; Didier Locca; Michael Roughton; Peter D. Gatehouse; David N. Firmin; Dudley J. Pennell

To compare a multislab three‐dimensional volume‐selective fast spin‐echo (FSE) magnetic resonance (MR) sequence with a routine two‐dimensional FSE sequence for quantification of carotid wall volume.


Circulation | 2009

Cardiovascular Magnetic Resonance of Thymoma

Agata Grasso; Rory O'Hanlon; Didier Locca; Dudley J. Pennell

A 50-year-old asymptomatic man was referred for cardiovascular magnetic resonance after the incidental finding of a mediastinal mass on echocardiography. In particular, the echocardiogram showed a mediastinal mass (6.5×10 cm) close to the right side of the heart without clear infiltration. Left and right ventricular function was normal. The chest x-ray showed the right-sided mediastinal mass obliterating the right heart border, with normal lung parenchyma. The ECG (Figure 1) showed sinus rhythm with normal atrioventricular conduction, left axis deviation, normal intraventricular conduction, and normal repolarization. The cardiac magnetic resonance confirmed the presence of a large encapsulated mediastinal mass (Figure 2) located superiorly in the right anterior mediastinum, adjacent to the ascending aortic wall, the superior vena cava, and the junction of the right ventricle outflow tract with the main pulmonary trunk. There was some compression of the right upper pulmonary vein but no …

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Dudley J. Pennell

National Institutes of Health

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Agata Grasso

Imperial College London

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Giuseppe Ferrante

Catholic University of the Sacred Heart

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Peter D. Gatehouse

National Institutes of Health

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Samir G. Agrawal

Queen Mary University of London

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