ABSTRACT
BACKGROUND: Recessive dystrophic epidermolysis bullosa (RDEB) is a hereditary blistering disorder due to a lack of type VII collagen. At present, treatment is mainly supportive. OBJECTIVES: To determine whether intravenous allogeneic bone marrow-derived mesenchymal stromal/stem cells (BM-MSCs) are safe in RDEB adults and if the cells improve wound healing and quality of life. METHODS: We conducted a prospective, phase I/II, open-label study recruiting 10 RDEB adults to receive 2 intravenous infusions of BM-MSCs (on day 0 and day 14; each dose 2-4 × 106 cells/kg). RESULTS: BM-MSCs were well tolerated with no serious adverse events to 12 months. Regarding efficacy, there was a transient reduction in disease activity scores (8/10 subjects) and a significant reduction in itch. One individual showed a transient increase in type VII collagen. LIMITATIONS: Open-label trial with no placebo. CONCLUSIONS: MSC infusion is safe in RDEB adults and can have clinical benefits for at least 2 months.
Subject(s)
Epidermolysis Bullosa Dystrophica/therapy , Mesenchymal Stem Cell Transplantation/methods , Pruritus/therapy , Adolescent , Adult , Aged , Epidermolysis Bullosa Dystrophica/complications , Epidermolysis Bullosa Dystrophica/diagnosis , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Prospective Studies , Pruritus/diagnosis , Pruritus/etiology , Quality of Life , Severity of Illness Index , Transplantation, Homologous/methods , Treatment Outcome , Wound Healing , Young AdultABSTRACT
Netherton syndrome (NS) is a rare autosomal recessive skin disorder caused by mutations in SPINK5. It is a debilitating condition with notable mortality in the early years of life. There is no curative treatment. We undertook a nonrandomized, open-label, feasibility, and safety study using autologous keratinocytes transduced with a lentiviral vector encoding SPINK5 under the control of the human involucrin promoter. Six NS subjects were recruited, and gene-modified epithelial sheets were successfully generated in three of five subjects. The sheets exhibited expression of correctly sized lympho-epithelial Kazal-type-related inhibitor (LEKTI) protein after modification. One subject was grafted with a 20 cm2 gene-modified graft on the left anterior thigh without any adverse complications and was monitored by serial sampling for 12 months. Recovery within the graft area was compared against an area outside by morphology, proviral copy number and expression of the SPINK5 encoded protein, LEKTI, and its downstream target kallikrein 5, which exhibited transient functional correction. The study confirmed the feasibility of generating lentiviral gene-modified epidermal sheets for inherited skin diseases such as NS, but sustained LEKTI expression is likely to require the identification, targeting, and engraftment of long-lived keratinocyte stem cell populations for durable therapeutic effects. Important learning points for the application of gene-modified epidermal sheets are discussed.
Subject(s)
Epidermal Cells/metabolism , Epidermis/metabolism , Epidermis/transplantation , Netherton Syndrome/genetics , Netherton Syndrome/therapy , Transduction, Genetic , Transgenes , Adolescent , Adult , Autografts , Biomarkers , Cell Culture Techniques , Female , Fluorescent Antibody Technique , Gene Expression , Genetic Engineering , Genetic Therapy , Genetic Vectors/administration & dosage , Genetic Vectors/genetics , Humans , Immunohistochemistry , Keratinocytes/metabolism , Lentivirus/genetics , Male , Mutation , Netherton Syndrome/metabolism , Netherton Syndrome/pathology , Serine Peptidase Inhibitor Kazal-Type 5/genetics , Serine Peptidase Inhibitor Kazal-Type 5/metabolism , Treatment Outcome , Young AdultABSTRACT
BACKGROUNDRecessive dystrophic epidermolysis bullosa (RDEB) is a severe form of skin fragility disorder due to mutations in COL7A1 encoding basement membrane type VII collagen (C7), the main constituent of anchoring fibrils (AFs) in skin. We developed a self-inactivating lentiviral platform encoding a codon-optimized COL7A1 cDNA under the control of a human phosphoglycerate kinase promoter for phase I evaluation.METHODSIn this single-center, open-label phase I trial, 4 adults with RDEB each received 3 intradermal injections (~1 × 106 cells/cm2 of intact skin) of COL7A1-modified autologous fibroblasts and were followed up for 12 months. The primary outcome was safety, including autoimmune reactions against recombinant C7. Secondary outcomes included C7 expression, AF morphology, and presence of transgene in the injected skin.RESULTSGene-modified fibroblasts were well tolerated, without serious adverse reactions or autoimmune reactions against recombinant C7. Regarding efficacy, there was a significant (P < 0.05) 1.26-fold to 26.10-fold increase in C7 mean fluorescence intensity in the injected skin compared with noninjected skin in 3 of 4 subjects, with a sustained increase up to 12 months in 2 of 4 subjects. The presence of transgene (codon-optimized COL7A1 cDNA) was demonstrated in the injected skin at month 12 in 1 subject, but no new mature AFs were detected.CONCLUSIONTo our knowledge, this is the first human study demonstrating safety and potential efficacy of lentiviral fibroblast gene therapy with the presence of COL7A1 transgene and subsequent C7 restoration in vivo in treated skin at 1 year after gene therapy. These data provide a rationale for phase II studies for further clinical evaluation.TRIAL REGISTRATIONClincalTrials.gov NCT02493816.FUNDINGCure EB, Dystrophic Epidermolysis Bullosa Research Association (UK), UK NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, and Fondation René Touraine Short-Exchange Award.