Dynamic of plasma IL-22 level is an indicator of thymic output after allogeneic hematopoietic cell transplantation

Life Sci. 2021 Jan 15:265:118849. doi: 10.1016/j.lfs.2020.118849. Epub 2020 Dec 2.

Abstract

Aims: Interleukin-22 (IL-22) promotes thymus recovery and improves T-cell recovery in preclinical allogeneic hematopoietic cell transplant models. However, the correlation between IL-22 and thymus recovery is unknown in human transplant.

Materials and methods: In this study, plasma IL-22 levels of transplanted humans were analyzed peri-transplant. Thymic output was assessed by detecting blood signal joint T-cell receptor excision circles (TRECs). Flow cytometry was applied to measure T-cell subsets.

Key findings: Plasma IL-22 level positively correlated with blood TRECs level at days 14 and 28 posttransplant. Multiple linear regression analysis showed plasma IL-22 level, occurrence of acute graft-versus-host disease (aGVHD) and age were significantly associated with blood TRECs level at day 28 after allotransplant. An increase of plasma IL-22 level during day 14 and day 28 correlated with faster recovery of blood TRECs and naïve T-cell levels in allotransplant recipients. Recipients with high TRECs levels at day 28 had lower incidence of aGVHD comparing with those who with low TRECs levels according to a median split of their TRECs levels, an effect also seen in the high IL-22 level and low IL-22 level cohorts. Other factors such as age and infection had impacts on plasma IL-22 level in allotransplants.

Significance: Our findings suggest that dynamic change of plasma IL-22 level is an indicator of thymic output and occurrence of aGVHD. Monitoring plasma IL-22 level might help to assess recovery of thymus function in human allotransplants.

Keywords: Allogeneic hematopoietic cell transplantation; Interleukin-22; Thymic output; Thymus.

MeSH terms

  • Adult
  • Flow Cytometry
  • Graft vs Host Disease / epidemiology*
  • Hematopoietic Stem Cell Transplantation / methods*
  • Humans
  • Incidence
  • Interleukin-22
  • Interleukins / blood*
  • T-Lymphocyte Subsets / immunology
  • Thymus Gland / metabolism*
  • Time Factors
  • Transplantation, Homologous
  • Young Adult

Substances

  • Interleukins