Bone Marrow Transplantation for Recessive Dystrophic Epidermolysis Bullosa

John E. Wagner, M.D., Akemi Ishida-Yamamoto, M.D., Ph.D., John A. McGrath, M.D., Maria Hordinsky, M.D., Douglas R. Keene, B.S., David T. Woodley, M.D., Mei Chen, Ph.D., Megan J. Riddle, B.A., Mark J. Osborn, Ph.D., Troy Lund, M.D., Ph.D., Michelle Dolan, M.D., Bruce R. Blazar, M.D., and Jakub Tolar, M.D., Ph.D.

N Engl J Med 2010; 363:629-639August 12, 2010DOI: 10.1056/NEJMoa0910501

Recessive dystrophic epidermolysis bullosa is an incurable, often fatal mucocutaneous blistering disease caused by mutations inCOL7A1, the gene encoding type VII collagen (C7). On the basis of preclinical data showing biochemical correction and prolonged survival in col7 −/− mice, we hypothesized that allogeneic marrow contains stem cells capable of ameliorating the manifestations of recessive dystrophic epidermolysis bullosa in humans.


Between October 2007 and August 2009, we treated seven children who had recessive dystrophic epidermolysis bullosa with immunomyeloablative chemotherapy and allogeneic stem-cell transplantation. We assessed C7 expression by means of immunofluorescence staining and used transmission electron microscopy to visualize anchoring fibrils. We measured chimerism by means of competitive polymerase-chain-reaction assay, and documented blister formation and wound healing with the use of digital photography.


One patient died of cardiomyopathy before transplantation. Of the remaining six patients, one had severe regimen-related cutaneous toxicity, with all having improved wound healing and a reduction in blister formation between 30 and 130 days after transplantation. We observed increased C7 deposition at the dermal–epidermal junction in five of the six recipients, albeit without normalization of anchoring fibrils. Five recipients were alive 130 to 799 days after transplantation; one died at 183 days as a consequence of graft rejection and infection. The six recipients had substantial proportions of donor cells in the skin, and none had detectable anti-C7 antibodies.


Increased C7 deposition and a sustained presence of donor cells were found in the skin of children with recessive dystrophic epidermolysis bullosa after allogeneic bone marrow transplantation. Further studies are needed to assess the long-term risks and benefits of such therapy in patients with this disorder. (Funded by the National Institutes of Health; number, NCT00478244.)

Figure 1. Clinical Photographs and Skin-Biopsy Specimens before and after Transplantation in Six Patients with Recessive Dystrophic Epidermolysis Bullosa.

Photographs and skin-biopsy specimens were taken immediately before treatment and at scheduled time points after transplantation. The clinical photographs show specific areas that were consistently blistered before treatment. More rapid wound healing and reepithelialization were noted after transplantation in all six patients, with variable reductions in skin blistering. In Patient 7, marked cutaneous toxicity developed (presumably as a result of the chemotherapy) and was most pronounced on day 17 after transplantation but showed marked improvement by day 25. Immunofluorescence staining for C7 was carried out with skin-biopsy specimens obtained from all six patients, with the use of anti-C7 antibodies provided by Drs. D.T. Woodley and M. Chen (Keck School of Medicine, University of Southern California) for Patient 1 and purchased from BD Biosciences for the other five patients. For Patient 1, immunofluorescence staining before transplantation revealed faint, stippled labeling of C7; continuous, bright, linear C7 labeling was observed at all time points after bone marrow infusion. For Patient 3, faint, stippled C7 labeling was also observed at the dermal–epidermal junction before transplantation and through day 60 after transplantation, with continuous, bright, linear C7 labeling noted on day 145. For Patient 4, a bright, continuous band was observed at the dermal–epidermal junction before transplantation, with the use of anti-C7 antibody from BD Biosciences, whereas a thicker, brighter band was noted on day 198 after transplantation; this observation was confirmed with the use of LH7.2 anti-C7 antibody from Sigma-Aldrich, with no labeling before transplantation but bright labeling on day 198. For Patient 5, faint, stippled C7 labeling was observed at the dermal–epidermal junction with loss of demonstrable C7 labeling early after transplantation (day 28); however, continuous, bright linear, C7 labeling was observed on day 180. For Patient 6, no immunofluorescence staining was detectable before transplantation or at any time after transplantation, through day 102. For Patient 7, immunofluorescence staining before transplantation revealed stippled C7 labeling and continuous, bright, linear C7 labeling at the dermal–epidermal junction as early as day 30 after transplantation. For Patients 3 through 7, keratinocytes (green) were visualized with the use of anti–cytokeratin 5 antibody.

Figure 3. Transmission Electron Micrographs Showing Fibril Formation in Skin Specimens from Patients 4 and 7.

Photomicrographs show thin fibrillar structures beneath the lamina densa before transplantation and on day 60 after transplantation in Patient 4 (Panel A, arrowheads) and before transplantation and on day 100 in Patient 7 (Panel B, arrowheads), with an increase in the number of fibrils after transplantation. Although some of these fibrils appear somewhat thicker in Patient 4 than in Patient 7 (Panel A, arrow), none bear the ultrastructural hallmarks of normal anchoring fibrils. The bars represent 250 nm.




Transferencia embrionaria de médula ósea (E-BMT) en la ciruclación fetal mejora la epidermolisis bullosa distrofica recesiva (RDEB) por medio de proveer fibrblastos a la piel y por inducir la tolerancia. (a,b). El ratón transgenico expresando GFP (médula osea expresando proteina fluorescente verde) fueron utilizados como donantes de células de médula ósea que fueron inyectados en el feto a traqves de la vena vitelina de las madres portadoras de embriones  Col7a1-/- . (c,e)Los ratones  Col7a1-/- no tratados muerieron los primeros dias postparto, mientras que los ratones que habín recibido la transferencia embrionica de médula osea sobrevivieron hasta 3 semanas. (d) Los ratones tratados con E-BMT demostraron un quimerismo de médula ósea detectado por la fluorescencia GFP. El examen de la piel reveló la presencia de células fibroblásticas GFP-positivas (verde) que demostraron la expresión del colágeno tipo VII (rojo); estas células fuero observadas frecuentemente en asociación con el folículo piloso. (h)Histopatología del recien nacido  Col7a1-/-  demostró la clara separación de la epidermis y la dermis mientras que (f) el raton tratado con E-BMT mostro la presencia de microampollas (g, señalada con asterisco).  Inducción de la tolerancia a GFP por E-BMT (i-k). La piel de un raton transgénico GFP-positivo fue injertada en un raton de 3 semnas de vida con o sin tratamiento previo por medio de transferencia de GFP-medula ósea embrionaria; Los injertos cutáneos fueron visualizados bajo luz normal (flecha negra) o luz fluorescente (flecha blanca)(j). Los injertos colocados en ratones no tratados fueron rechazados en las primeras 5 semanas tras el injerto, mientras que los injertos colocados en ratones previamente tratados con E-BMT persitieron más alla de las 8 semanas tras el injerto (k), por lo que la tolerancia del raton embrinario por medio de la transferencia de médula ósea ofrece un camino para prevenir la formación de anticuepors tras el tratamietno a una edad más tardía.

Trends in molecular medicine 2009 15:285.