Patient-derived Skin Graft Found to Treat RDEB in Boy, 13

A 13-year-old boy with recessive dystrophic epidermolysis bullosa (RDEB) had his skin lesions eased after surgeons transplanted a skin graft grown from his back, according to a case study report.

The study, “A case of recessive dystrophic epidermolysis bullosa treated with a cultured epidermal autograft,” was published in The Journal of Dermatology.

Dystrophic epidermolysis bullosa is a rare, inherited skin disease caused by mutations in the COL7A1 gene. This gene produces type VII collagen, essential to connect the different layers of the skin. Defects in this gene result in skin blistering and scars.

This case report from Japan described a boy with RDEB and a history of widespread skin ulcers since birth. Genetic testing revealed the presence of two mutations in the COL7A1 gene, one in each gene copy. Both mutations had been previously reported.

Around 7% of the patient’s body had skin erosions. Blood tests revealed anemia, as shown by low hemoglobin levels at 5.6 mg/L, and malnutrition, as evidenced by the amount of albumin protein. His levels of C-reactive protein were high, indicating inflammation. These symptoms gradually worsened despite treatment.

The patient underwent a skin transplant using his own cells. For the procedure, known as cultured epidermal autograft or CEA, the clinicians collected skin tissue from a region without blisters on the boy’s back. The cells were grown in the lab to generate larger grafts, which were then applied to more than 20 affected skin sites.

Four weeks following the graft, the team observed new skin formation, called epithelization, in nearly 27.5% of transplanted areas. Yet, skin ulcers still recurred, especially in areas prone to friction, including the kneecap and the back.

Skin formation was maintained in about 23.4% of the treated areas 12 weeks (about three months) after the transplant.

Previous research has indicated that some keratinocytes — the main cell type in the skin’s outer layer — do not carry the genetic mutation that causes EB, supporting their usefulness in generating skin grafts for transplant. This genetic phenomenon is called revertant mosaicism (RM), which refers to the co-existence of cells carrying disease-causing mutations with cells in which the inherited mutation was spontaneously corrected. However, no signs of RM were detected in genetic analysis.

Even without RM, skin grafting appeared effective for six months.

“This is the fourth case of dystrophic EB in Japan that was treated with CEA since the procedure became covered by health insurance,” the researchers wrote, noting that “assessment on its long-term safety and usefulness is required.”

The investigators noted that the number of patients receiving a skin graft is increasing “steadily” in Japan.

“CEA transplantation should be considered as treatment option in EB patients, regardless of RM,” they concluded.