The immune microenvironment plays an important role in leukemia treatment. However, a specific single-cell profiling of the immune alteration in bone marrow of chronic myeloid leukemia (CML) patients is still lacking. We performed multi-level single-cell sequencing to systematically decipher the bone marrow T cell atlas of CML patients. The results exhibited extensive changes of T cells, including the decreased CD4 T cells and increased CD8 T cells in the CML bone marrow. Subpopulation analysis revealed a significant increase of CD8 terminal effector (TE) cells and a significant decrease of CD4 naïve T cells. T cell receptor sequencing showed that the overall diversity of the T cell receptor repertoire was reduced in CML, with the exception of the CD8 TE cell. In addition, CD8 TE cells were the main source of gene expression differences in CD8 T cells. Intercellular communication analysis revealed the altered interaction between CD8 TE and other non-T cells in CML, including neutrophil subtype, indicating the potential regulation of bone marrow microenvironment cells on CD8 TE dynamics. Collectively, our work characterises the alteration of T cell subsets in CML patients at multiple single-cell levels, providing a valuable resource for understanding the immune microenvironment and developing new immune strategies for CML therapy.
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The aim of this study was to compare the expression levels of Fas and Fas ligand (FasL) in first-trimester placentas obtained from spontaneous abortions in patients with antiphospholipid antibody syndrome (APS) or factor V (FV) Leiden mutation, compared with values in placentas from induced abortions in patients negative for these conditions.
We studied explants from 6- to 10-week-old placentas that had been prepared by collagenase digestion from 10 spontaneous abortions from APS-positive patients, nine spontaneous abortions in patients positive for FV Leiden mutation, and 10 induced abortions. All tissues were analyzed by flow cytometry for expression of Fas and FasL.
Flow cytometric analysis showed that placental FasL expression was significantly lower in abnormal pregnancies than in normal ones. However, no such difference was observed for Fas expression.
FasL on placental cells may be involved in the maintenance of immune privilege, thereby ensuring the safety and growth of placental tissues. Dysregulation of apoptotic mechanisms may play a critical role in spontaneous abortions.