T-cell deplete versus T-cell replete haploidentical hematopoietic stem cell transplantation for sickle cell disease: where are we?

ABSTRACT

Introduction: Severe sickle cell disease is associated with progressive end-organ damage and early mortality in adults. While allogeneic hematopoietic cell transplant from a matched related donor is curative, the vast majority of patients do not have a compatible sibling. Accordingly, platforms using haploidentical donors have been developed, which provide near-universal availability.

Areas covered: This review focuses on the two commonly used approaches for haploidentical hematopoietic transplants, namely T-cell deplete and T-cell replete, each of which is associated with unique benefits and drawbacks. The purpose of this paper is to facilitate individualized decision-making for patients and providers by reviewing the pros- and cons of these differing approaches.

Expert opinion: Individuals with sickle cell disease eligible for a hematopoietic cell transplant can be considered based on recent results. Comparable outcomes are seen with T-cell deplete and T-cell replete approaches. The choice depends largely on institutional preference.

KEYWORDS:

• Haploidentical transplant
• sickle cell disease
• T-cell replete
• T-cell deplete
• graft-versus-host disease
• viruses

Article highlights

• Haplo-HCT approaches address the key issue of lack of donor availability in the use of transplant as a curative modality for severe sickle cell disease.

• TCD haplo-HCT approaches require technical expertise in graft manipulation, and as a result, are available at only specialized centers compared to TCR-based approaches.

• Both TCD and TCR approaches are associated increased infectious risks, especially viral reactivations/infections.

• Haplo-HCT with post-transplant cyclophosphamide plus thiotepa results in favorable transplant-related outcomes, namely improved engraftment and reduced rejection.

• Further comparative studies are needed to better understand long-term outcomes following TCD and TCR haplo-HCT approaches for sickle cell disease.

Acknowledgments

The authors would like to acknowledge all of the staff at Vanderbilt University Medical Center and Vanderbilt Ingram Cancer Center for their work in providing stem cell transplants for patients with sickle cell disease. Image Credit for Figure 1: Andrea Sikora Newsome, PharmD, BCPS, BCCCP (contact [email protected]). 1120 15^th Street, HM −118, Augusta, GA, 30912-5536. Image Credit for Figures 1 and 2: Katie S. Gatwood, PharmD, BCOP (contact [email protected]). Department of Pharmaceutical Services, Vanderbilt University Medical Center, Nashville, TN, 37212.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or conflict with the subject matter or materials discussed in this manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This paper was not funded.