mi ‐ RNA ‐ mRNA Alterations in Sorted T‐Cells of Acquired Aplastic Anemia: Validating the Observations of a Pilot Study

Introduction An altered T‐cell repertoire with aberrant immune activation is central to the pathogenesis of acquired aplastic anemia (aAA), and miRNAs are known to orchestrate T‐cell activation; their relationship is, however, incompletely explored in aAA. The study aimed to validate specific miRNA‐mRNA pairs involved in aberrant T‐cell activation, differentiation, and cytokine levels in aAA. Methods This was a prospective case–control study of 30 newly diagnosed patients with aAA and 10 healthy controls. The alterations in the expression of seven miRNAs were evaluated in the sorted T‐cells isolated from the PB‐MNCs. qRT‐PCR was used to evaluate the miRNA expression, and fold change was calculated by the 2 ΔΔ Ct method. Target genes of the deregulated miRNAs were assessed by qRT‐PCR. Cytokine profiling was carried out by cytokine bead array and qRT‐PCR. Results All seven miRNAs were differentially expressed in aAA, miR‐155 (FC: 3.71) and miR‐146b (fold change (FC): 5.86) were upregulated, while miR‐126 (FC: 0.305), miR‐181c (FC: 0.343), miR‐16 (FC: 0.351), miR‐326 (FC: 0.219), and miR‐17 (FC: 0.38) were downregulated. These alterations correlated with disease severity. Target analysis showed increased expression of transcription factors promoting Th1/Th17 polarization and signaling molecules (PIK3R2, SOCS‐1), with reduced expression of FOXP3, IRAK‐1, TRAF‐6, STAT‐1, IFNGR, ETS‐1, and PTEN. The miRNA‐mRNA alterations in enriched T‐cells mirrored those in PB‐MNCs except for miR‐17. Plasma levels of IL‐2, IL‐4, IL‐6, and IL‐10 ( p = 0.069) were significantly elevated in aAA. Conclusion This study confirms the differential expression of miRNAs in aAA and their possible role in maintaining the aberrant T‐cell repertoire in aAA. In vitro studies utilizing miRNA knockdown/miR‐mimics may uncover newer therapeutic targets in aAA.