Background Wiskott-Aldrich syndrome is a rare, life-threatening, X-linked primary immunodeficiency characterised by microthrombocytopenia, infections, eczema, autoimmunity, and malignant disease. Lentiviral vector-mediated haemopoietic stem/progenitor cell (HSPC) gene therapy is a potentially curative treatment that represents an alternative to allogeneic HSPC transplantation. Here, we report safety and efficacy data from an interim analysis of patients with severe Wiskott-Aldrich syndrome who received lentiviral vector-derived gene therapy. MethodsWe did a non-randomised, open-label, phase 1/2 clinical study in paediatric patients with severe Wiskott-Aldrich syndrome, defined by either WAS gene mutation or absent Wiskott-Aldrich syndrome protein (WASP) expression or a Zhu clinical score of 3 or higher. We included patients who had no HLA-identical sibling donor available or, for children younger than 5 years of age, no suitable 10/10 matched unrelated donor or 6/6 unrelated cord blood donor. After treatment with rituximab and a reduced-intensity conditioning regimen of busulfan and fludarabine, patients received one intravenous infusion of autologous CD34+ cells genetically modified with a lentiviral vector encoding for human WAS cDNA. The primary safety endpoints were safety of the conditioning regimen and safety of lentiviral gene transfer into HSPCs. The primary efficacy endpoints were overall survival, sustained engraftment of genetically corrected HSPCs, expression of vector-derived WASP, improved T-cell function, antigen-specific responses to vaccinations, and improved platelet count and mean platelet volume normalisation. This interim analysis was done when the first six patients treated had completed at least 3 years of follow-up. The planned analyses are presented for the intention-to-treat population. This trial is registered with ClinicalTrials.gov (number NCT01515462) and EudraCT (number 2009-017346-32). Findings Between April 20, 2010, and Feb 26, 2015, nine patients (all male) were enrolled of whom one was excluded after screening; the age range of the eight treated children was 1·1-12·4 years. At the time of the interim analysis (data cutoff April 29, 2016), median follow-up was 3•6 years (range 0•5-5•6). Overall survival was 100%. Engraftment of genetically corrected HSPCs was successful and sustained in all patients. The fraction of WASP-positive lymphocytes increased from a median of 3•9% (range 1·8-35·6) before gene therapy to 66•7% (55·7-98·6) at 12 months after gene therapy, whereas WASP-positive platelets increased from 19•1% (range 4·1-31·0) to 76•6% (53·1-98·4). Improvement of immune function was shown by normalisation of in-vitro T-cell function and successful discontinuation of immunoglobulin supplementation in seven patients with follow-up longer than 1 year, followed by positive antigen-specific response to vaccination. Severe infections fell from 2•38 (95% CI 1·44-3·72) per patient-year of observation (PYO) in the year before gene therapy to 0•31 (0·04-1·11) per PYO in the second yea...

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BackgroundTo report early and long-term outcomes of patients undergoing minimally invasive mitral valve surgery (MIMVS) through right mini-thoracotomy (RT) over a 10-year period.MethodsFrom September 2003 to December 2013, a total of 1604 consecutive patients underwent MIMVS through RT.ResultsThe mean age was 63 ± 13 years, 770 (48 %) patients were female and 218 (13.6 %) had previous cardiac operations. The most predominant pathology was degenerative disease (70 %), followed by functional mitral valve regurgitation (12 %), rheumatic disease (9.4 %), endocarditis (5 %) and prosthetic dysfunction (3.2 %). Mitral valve repair was performed in 1137 (71 %) patients and 476 (29 %) had mitral valve replacement. Direct aortic cannulation was achieved in 1325 (83 %) patients. Among patients with degenerative disease candidate for repair (n = 958), rate of mitral valve repair was 95 %. Repair techniques included annuloplasty (95 %), leafleat resection (63 %), neochordae implantation (16 %) and sliding plasty (11 %). Concomitant procedures included tricuspid valve repair (14.6 %), atrial fibrillation ablation (9.5 %) and atrial septal defect closure (3.2 %). Overall in-hospital mortality was 1.1 %. Thirty-four patients (2.1 %) had conversion to sternotomy. Incidence of stroke was 2 %. Overall survival at 10 years was 88 ± 2 %. Freedom from reoperation at 10 years was 94 ± 2 % for repair and 80 ± 6 % for replacement. Freedom from recurrent mitral regurgitation >3+ at 10 years was 90 ± 3 %.ConclusionsMinimally invasive mitral valve surgery is a safe and reproducible approach associated with low mortality and morbidity, high rate of mitral valve repair and excellent late results.

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Few children have been reported to have been affected by novel coronavirus disease 2019 (COVID-19); it is unclear whether children are less likely to be infected or rather display fewer symptoms. We present the case of a 32-day-old boy infected by COVID-19 that presented with an upper air way infection which resolved spontaneously and did not require any therapy. We argue that in epidemic settings children presenting with any mild symptom potentially attributable to COVID-19 should be considered contagious until proven otherwise, and that management must be guided by clinical conditions.

In the field of hematology, gene therapies based on integrating vectors have reached outstanding results for a number of human diseases. With the advent of novel programmable nucleases, such as CRISPR/Cas9, it has been possible to expand the applications of gene therapy beyond semi-random gene addition to site-specific modification of the genome, holding the promise for safer genetic manipulation. Here we review the state of the art of ex vivo gene editing with programmable nucleases in human hematopoietic stem and progenitor cells (HSPCs). We highlight the potential advantages and the current challenges toward safe and effective clinical translation of gene editing for the treatment of hematological diseases.

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Collection of an adequate amount of autologous hematopoietic stem progenitor cells (HSPC) is required for ex vivo manipulation and successful engraftment for certain inherited disorders. Fifty-seven paediatric patients (age 0.5-11.4 years) underwent a bone marrow harvest for the purpose of HSPC gene therapy (GT), including adenosine deaminase severe combined immunodeficiency (ADA-SCID), Wiskott Aldrich syndrome (WAS) and metachromatic leukodystrophy (MLD) patients. Total nucleated cells and percentage and absolute counts of CD34+ cells were calculated at defined steps of the procedure (harvest, CD34+ cell purification, transduction with the gene transfer vector and infusion of the medicinal product). Minimum CD34+ cell dose for infusion was 2x106/kg, with optimal target at 5-10x106/kg. Median volume of bone marrow harvested was 34.2 ml/kg (range 14.2-56.6). The number of CD34+ cells collected correlated inversely with weight and age in all patients and particularly in the MLD children group. All patients reached the minimum target dose for infusion: median dose of CD34+ cells/kg infused was 10.3 x106/kg (3.7-25.9), with no difference among the 3 groups. Bone marrow harvest of volumes >30 ml/kg in infants and children with ADA-SCID, WAS and MLD is well tolerated and allows obtaining an adequate dose of medicinal product for HSPC-GT.