The following is a summary of “Aberrant expression of T cell activation markers and upregulation of Tregs in bone marrow and peripheral blood in acute myeloid leukemia patients,” published in the June 2023 issue of Hematology by Fang, et al.

The function and activation of T cells and the immunosuppressive effects of regulatory T cells (Tregs) play a crucial role in the development and progression of acute myeloid leukemia (AML). For a study, researchers sought to investigate the expression of T cell activation markers and the quantity of Tregs in the bone marrow (BM) and peripheral blood (PB) of AML patients and examine their correlation with BM leukemic blasts.

They used flow cytometry to measure the expression of CD25, CD38, CD69, and HLA-DR on the surfaces of CD4⁺ and CD8 T cells, as well as the quantity of Tregs in the BM and PB of newly diagnosed (ND), relapsed-refractory (RR), and complete remission (CR) AML patients.

Compared to normal controls (NC), they observed a higher proportion of CD4⁺ CD69 T cells, CD8⁺ CD69⁺ T cells, and Tregs in the PB of AML patients. RR patients exhibited significantly higher CD8⁺ CD38 T cells and CD8 HLA-DR⁺ T cells than ND, CR, and NC individuals. The quantity of Tregs normalized when AML patients achieved CR. Furthermore, they found a weak positive correlation between AML blasts and CD8⁺ CD25⁺ T cells or Tregs, while AML blasts showed a weak negative correlation with CD4⁺ CD69⁺ T cells.

Abnormal activation markers on T cells and Tregs may be involved in the pathological mechanisms of ND and RR AML. The findings suggested that CD8⁺ CD38⁺ T cells and CD8⁺ HLA-DR⁺ T cells could be markers for disease relapse in AML patients. Additionally, Tregs may be used as clinical indicators to evaluate the prognosis of AML patients.

Source: tandfonline.com/doi/full/10.1080/16078454.2023.2219554