Serial transplantation of mismatched donor hematopoietic cells between HLA-identical sibling pairs with congenital immunodeficiency: in vivo tolerance permits rapid immune reconstitution following T-replete transplantation without GVHD in the secondary recipient

Ethical considerations of using a single minor donor for three bone marrow harvests for three HLA-matched siblings with primary immunodeficiency

Allogeneic hematopoietic stem cell transplantation is curative for primary immunodeficiencies. Bone marrow from an unaffected human leukocyte antigen (HLA)-identical sibling donor is the ideal graft source. For minor donors, meaningful consent or assent may not be feasible, and permission from parents or legal guardians is considered acceptable. Adverse events, albeit extremely small, can be associated with bone marrow harvest in pediatric donors. Donor safety concerns potentially increase with multiple bone marrow harvests. Very little is known about multiple bone marrow harvests from pediatric donors. We describe the ethical considerations and clinical decision-making in an unusual clinical situation where three patients with the same primary immunodeficiency were HLA identical to one another and their younger sibling, who underwent bone marrow harvests three times between 1.3 and 4 years of age, resulting in successful transplantation for all three patients. We hope that this experience will provide guidance to providers and families in a similar situation.

Transplantation in identical twins: another option for breast reconstruction

BACKGROUND

Deriving their name from the Greek word plastikos, meaning related to molding, plastic surgeons have made their reputation by transplanting tissues from one area of the body to another to "remold" defects caused by trauma, congenital anomaly, or disease. Dr. Joseph Murray, a plastic surgeon, performed the first successful kidney transplant between identical twins in 1954. The authors present three cases involving the transplantation of perforator flaps from one identical twin to another for breast reconstruction, including cases using both deep inferior epigastric perforator and superficial inferior epigastric artery flaps.

METHODS

Three sets of recipient monozygotic twins that had breasts treated with mastectomies underwent reconstruction using transplanted tissue from their donor monozygotic twins. All sets of twins underwent DNA testing to determine that they were monozygotic; therefore, no immunosuppressive therapy was indicated.

RESULTS

The three sets of recipient monozygotic twins underwent successful breast reconstruction using perforator flap transplants from their donor monozygotic twins. The operations included two unilateral reconstructions (one using a deep inferior epigastric perforator flap and the other using a superficial inferior epigastric artery flap) and one bilateral deep inferior epigastric perforator reconstruction. Their hospital courses were unremarkable.

CONCLUSIONS

Transplant surgery continues to evolve in the twenty-first century. The authors present three cases of breast reconstruction using skin flap transplantation as a new option for breast reconstruction.

Wiskott-Aldrich syndrome

PURPOSE OF REVIEW

Wiskott-Aldrich syndrome is caused by mutations of the Wiskott-Aldrich syndrome protein gene, which codes for a cytoplasmic protein with multiple functions. This review will focus on recent progress in understanding the molecular basis of Wiskott-Aldrich syndrome and its ramifications for the cure of this lethal disease.

RECENT FINDINGS

The discovery of the causative gene has revealed a spectrum of clinical phenotypes demonstrating a strong genotype/phenotype correlation. The discovery of unique functional domains of Wiskott-Aldrich syndrome protein has been instrumental in defining mechanisms that control activation of Wiskott-Aldrich syndrome protein. Long-term follow up of patients undergoing hematopoietic stem cell transplantation has led to important modifications of the procedure. Studies of Wiskott-Aldrich syndrome protein-deficient cell lines and wasp-knockout mice have paved the way for possible gene therapy.

SUMMARY

Wiskott-Aldrich syndrome protein gene mutations result in four clinical phenotypes: classic Wiskott-Aldrich syndrome and X-linked thrombocytopenia, intermittent thrombocytopenia and neutropenia. Wiskott-Aldrich syndrome protein is a signaling molecule and instrumental for cognate and innate immunity, cell motility and protection against autoimmune disease. The success of hematopoietic stem cell transplantation is related to the recipient's age, donor selection, the conditioning regimen and the extent of reconstitution. Since Wiskott-Aldrich syndrome protein is expressed exclusively in hematopoietic stem cells, and because Wiskott-Aldrich syndrome protein exerts a strong selective pressure, gene therapy is expected to cure the disease.