The role of immune reconstitution in relapse after allogeneic hematopoietic stem cell transplantation

ABSTRACT

Introduction

Leukemia relapse following stem cell transplantation remains a significant barrier to long-term remission. Timely and balanced immune recovery after transplantation is crucial for preventing leukemia relapse.

Areas covered

After an extensive literature search of PubMed and Web of Science through October 2023, we provide an overview of the dynamics of immune reconstitution and its role in controlling leukemia relapse. We also discuss strategies to promote immune reconstitution and reduce disease recurrence following allogeneic hematopoietic stem cell transplantation.

Expert opinion

Immune reconstitution after transplantation has substantial potential to prevent relapse and might predict disease recurrence and prognosis. High dimensional cytometry, multi-omics, and T cell repertoire analysis allow for a more comprehensive and detailed understanding of the immune system’s dynamics post-transplantation, and contribute to the identification of rare immune cell subsets or potential biomarkers associated with successful immune reconstitution or increased risk of complications. Strategies to enhance the immune system, such as adoptive immunotherapy and cytokine-based therapy, have great potential for reducing leukemia relapse after transplantation. Future research directions should focus on refining patient selection for these therapies, implementing appropriate and timely treatment, investigating combination approaches to maximize therapeutic outcomes, and achieving a robust graft-versus-leukemia (GVL) effect while minimizing graft-versus-host disease (GVHD) for optimal results.

KEYWORDS:

• Allogeneic hematopoietic stem cell transplantation
• immune reconstitution
• relapse
• innate immunity
• adaptive immunity
• graft-versus-leukemia effect
• high dimensional cytometry
• strategy

Article highlights

• Leukemia relapse is a major factor affecting the long-term survival of recipients after allogeneic hematopoietic stem cell transplantation (allo-HSCT).

• Immune reconstitution after allo-HSCT is a complex and dynamic process involving the recovery of various immune cell populations.

• Timely activation of anti-leukemic innate and adaptive immune recovery after allo-HSCT is crucial for preventing leukemia relapse.

• High-throughput sequencing and single cell analysis allow for a more comprehensive and detailed understanding of the immune system’s dynamics post-transplantation.

• Strategies to enhance the immune system, such as adoptive immunotherapy and cytokine-based therapy, have great potential for reducing leukemia relapse after transplantation.

Declaration of interest

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

Reviewer disclosures

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

Author contributions

Xiaojun Huang and Xuying Pei wrote the manuscript and revised it for important intellectual content. All authors agree for the final version of the manuscript to be published.

Additional information

Funding

This paper was funded by the National Key Research and Development Program of China [grant number 2022YFA0103300], Sponsored by Being Nova Program [grant number 20220484076], Peking University Medicine Fund for world’s leading discipline or discipline cluster development [grant number 71003Y3035], and Peking University People’s Hospital Research And Development Funds [grant number RS 2021-01].