Intérêt des greffes de peau en pastilles dans les épidermolyses bulleuses dystrophiques. À propos de quatre cas

Immune tolerance of allogeneic haematopoietic cell transplantation supports donor epidermal grafting of recessive dystrophic epidermolysis bullosa chronic wounds

BACKGROUND

Chronic wounds, a common morbidity in recessive dystrophic epidermolysis bullosa (RDEB), lack definitive therapies.

OBJECTIVES

To assess allogeneic epidermal skin grafts in terms of wound healing and durability over time.

METHODS

In a prospective, open-label clinical trial for postallogeneic haematopoietic cell transplantation (post-alloHCT) patients with RDEB, up to nine chronic wounds per patient were grafted over 1 year. Epidermal grafts measuring 5 cm² were obtained from related alloHCT donors in the outpatient setting using the CELLUTOME^TM Epidermal Harvesting System. Wounds were photographed and symptom inventories completed at baseline and 6, 12 and 52 weeks after grafting. The trial was registered at ClinicalTrials.gov (NCT02670837).

RESULTS

Between August 2016 and January 2019, eight patients with RDEB received a total of 35 epidermal allografts at a median of 1157 days (range 548-2884) post-alloHCT. The median (interquartile range) percentage reductions in wound surface area were 75% (52-94), 95% (72-100) and 100% (97-100) at 6, 12 and 52 weeks postgraft, respectively, each significantly reduced from baseline (P < 0·001). Donor harvest sites healed quickly without scarring. Biopsy evaluation at 1 year of an epidermal allograft site revealed wildtype type VII collagen (immunofluorescence), anchoring fibrils (electron microscopy), and full-thickness skin whole-DNA donor chimerism of 42% (compared with 16% in concurrently biopsied native skin). This strategy subsequently supported release of RDEB pseudosyndactyly.

CONCLUSIONS

The immune tolerance established by alloHCT supports successful adoptive transfer of donor epidermal grafts. Persistence of donor grafts in a single patient beyond 1 year and observed migration of donor-grafted cells into adjacent wound suggest that epidermal allografts include nonterminally differentiated cells and/or trigger recruitment of donor bone-marrow-derived cells to mediate wound healing.

Punch grafting of chronic ulcers in patients with laminin-332-deficient, non-Herlitz junctional epidermolysis bullosa

BACKGROUND

Epidermolysis bullosa (EB) is a genetic, heterogeneous, trauma-induced blistering disease. Patients with laminin-332-deficient non-Herlitz junctional EB (JEB-nH) can have impaired wound healing witnessed by persistent, small, deep ulcers on the hands and feet that adversely affect the quality of life.

OBJECTIVE

We sought to present the results of punch grafting in patients with laminin-332-deficient JEB-nH, and to discuss its therapeutic value.

METHODS

Retrospective analysis of the Dutch EB Registry revealed 4 patients with laminin-332-deficient JEB-nH who were treated with punch grafting. Punch grafting was performed according to protocol, and the patients were followed up.

RESULTS

In the past 10 years we have treated 23 ulcers in 4 patients with JEB-nH using punch grafting without any complications or adverse effects. The ulcers had on average persisted 6 years before treatment. Healing rate after punch grafting was 70% (n = 16), with a mean healing time of 2 months. Thirty percent (n = 7) of the treated ulcers did not completely heal, but did show improvement. The recurrence rate after 3 months was 13% (n = 2), and was a result of renewed blistering.

LIMITATIONS

Limitations of the study are the retrospective design, small number of patients, absence of a control group, and follow-up and ulcer measurement that were not standardized.

CONCLUSIONS

Punch grafting can be used as a first-line treatment in small persistent ulcers in patients with JEB-nH. The method is easy, is inexpensive, has little risk of complications, and results in significant healing rates and improvement in quality of life.