In Silico Perturbation Identifies Transcription Factors as Protective Targets in HSPCs After Irradiation

Hematopoietic stem and progenitor cells (HSPCs) in the bone marrow are highly vulnerable to radiation-induced damage. Systematic delineation of lineage-specific transcription factor (TF) programs, together with in silico perturbation analyses, provides a valuable approach for identifying regulators capable of accelerating hematopoietic reconstruction after irradiation. Here, using single-cell RNA sequencing (scRNA-seq), we characterized the dynamics of HSPCs at both cellular abundance and transcriptional regulation levels following irradiation and used in silico TF perturbation to predict their effects on lineage commitment. We found that granulocyte-macrophage progenitor (GMP) differentiation is consistently prioritized after irradiation, accompanied by enhanced activity of proliferation-associated drivers. Network-based TF profiling identified Tcf7l2 as a previously unrecognized regulator of early lymphoid differentiation. In silico perturbation further functionally predicted TFs driving differentiation in HSPCs after irradiation, and Hsf1, a factor with pharmacological activation potential, was selected for validation via in vivo celastrol treatment and in vitro knockdown. Collectively, our findings uncover the transcriptional programs governing HSPC lineage biases after radiation exposure and highlight the utility of in silico TF perturbation as a strategy for guiding the therapeutic interventions for radiation-induced hematopoietic injury.