B Cell Reconstitution and Influencing Factors After Hematopoietic Stem Cell Transplantation in Children

Abstract

B cell reconstitution after hematopoietic stem cell transplantation (HSCT) is variable and influenced by different patient, donor, and treatment related factors. In this review we describe B cell reconstitution after pediatric allogeneic HST, including the kinetics of reconstitution of the different B cell subsets and the development of the B cell repertoire, and discuss the influencing factors. Observational studies show important roles for stem cell source, conditioning regimen, and graft vs. host disease in B cell reconstitution. In addition, B cell recovery can play an important role in post-transplant infections and vaccine responses to encapsulated bacteria, such as pneumococcus. A substantial number of patients experience impaired B cell function and/or dependency on Ig substitution after allogeneic HSCT. The underlying mechanisms are largely unresolved. The integrated aspects of B cell recovery after HSCT, especially BCR repertoire reconstitution, are awaiting further investigation using modern techniques in order to gain more insight into B cell reconstitution and to develop strategies to improve humoral immunity after allogeneic HSCT.

T cell regeneration after immunological injury

“…Activation of signal transducer and activator of transcription 3 (STAT3) signalling has been linked to the induction of apoptosis in TECs after irradiation 60 . However, more recent studies show that STAT3-mediated signalling is essential for growth and architectural organization of Compared with our understanding of T cell reconstitution, less information is available regarding the kinetics of B cell recovery after immunological insults and the factors regulating this process 258 . Optimal B cell function is important not only for the generation of protective antibodies and efficient antigen presentation but also for proper immune tolerance.…”

“…Compared with our understanding of T cell reconstitution, less information is available regarding the kinetics of B cell recovery after immunological insults and the factors regulating this process 258 . Optimal B cell function is important not only for the generation of protective antibodies and efficient antigen presentation but also for proper immune tolerance.…”

“…B cell numbers generally return to normal levels within 12 months after HCT, but it can take up to 2 years for complete recovery of the B cell compartment 259 , 261 . Several factors such as conditioning regimens , total body irradiation, corticosteroid treatment and GVHD negatively impact B cell reconstitution 77 , 258 , 262 . B cell-targeting therapies such as the monoclonal anti-CD20 agent rituximab also significantly delay B cell recovery 263 .…”

Associations between the Gut Microbiota, Immune Reconstitution, and Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation

“…2021;3(1):e210004. https://doi.org/10.20900/immunometab20210004 Immunometabolism 3 of 20 relapse mortality [14,29]. Thus, the kinetics of reconstitution of numerous distinct immune subsets contribute to the outcomes of allo-HSCT.…”

“…Early recovery associated with less infection [14,29] Early recovery associated with decreased risk of aGVHD [29] Abbreviations: aGVHD, acute graft versus host disease; NK, natural killer; Th, T helper cell; Treg, T regulatory cell.…”