In:
Frontiers in Oncology, Frontiers Media SA, Vol. 11 ( 2021-12-7)
Abstract:
In patients who have undergone allogeneic hematopoietic cell transplantation (HCT), myeloid mixed donor chimerism (MC) is a risk factor for disease relapse. In contrast, several studies found favorable outcome in patients with lymphoid MC. Thus far, most studies evaluating MC focused on a short-term follow-up period. Here, we report the first case series of long-term survivors with MC. We screened 1,346 patients having undergone HCT for myeloid neoplasms at our center from 1996 to 2016; 443 patients with data on total peripheral blood mononuclear cells (PBMC)/CD4 + /CD34 + short tandem repeat (STR) donor chimerism (DC) and follow-up ≥24 months post-HCT were included. We identified 10 patients with long-term MC (PBMC DC & lt;95% at ≥12 months post-HCT). Median follow-up was 11 years. All patients had received combined ex vivo/in vivo T cell-depleted (TCD) peripheral blood stem cells; none experienced ≥grade 2 acute graft-versus-host disease (GVHD). The mean total PBMC, CD4 + , and CD34 + DC of all patients were 95.88%, 85.84%, and 90.15%, respectively. Reduced-intensity conditioning (RIC) was associated with a trend to lower mean total DC. Of note, two patients who experienced relapse had lower CD34 + DC but higher CD4 + DC as compared with patients in continuous remission. Bone marrow evaluation revealed increased CD4 + /FOXP3 + cells in patients with MC, which might indicate expansion of regulatory T cells (T regs ). Our results support known predictive factors associated with MC such as RIC and TCD, promote the value of CD34 + MC as a potential predictor of relapse, highlight the potential association of CD4 + MC with reduced risk of GVHD, and indicate a possible role of T regs in the maintenance of immune tolerance post-HCT.
Type of Medium:
Online Resource
ISSN:
2234-943X
DOI:
10.3389/fonc.2021.776946
DOI:
10.3389/fonc.2021.776946.s001
Language:
Unknown
Publisher:
Frontiers Media SA
Publication Date:
2021
detail.hit.zdb_id:
2649216-7
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