Decoding immune-driven erythroid failure in pure red cell aplasia

Pure red cell aplasia (PRCA) is increasingly recognised as a T-cell-mediated bone marrow failure syndrome, yet its immunogenetic drivers remain poorly defined. In their paper, Yamashita et al. integrate human leucocyte antigen (HLA) typing, T-cell receptor repertoire analysis and mutational profiling to reveal enriched HLA alleles, signal transducer and activator of transcription 3 (STAT3)-mutated T-cell clones and a shared T cell receptor beta (TCRβ) motif in PRCA patients. These findings suggest that antigen-driven cytotoxic T-cell responses represent a central mechanism underlying erythroid suppression. Commentary on: Yamashita et al. Immunological features of acquired pure red cell aplasia: Specific human leucocyte antigen alleles, signal transducer and activator of transcription 3 mutations and a unique T- cell receptor beta motif. Br J Haematol 2026; 208:1797-1805.