Single-Cell RNA Sequencing to Guide Autologous Preterm Cord Mesenchymal Stromal Cell-Therapy

The chronic lung disease bronchopulmonary dysplasia (BPD) remains the most common complication of extreme prematurity (<28 weeks of gestation). Umbilical cord-derived mesenchymal stromal cells (UC-MSCs) represent an opportunity for autologous cell-therapy, as UC-MSCs have been shown to improve lung function and structure in experimental BPD. However, characterization and repair capacity of UC-MSCs derived from donors with pregnancy-related complications associated with prematurity remain unexplored. To characterize UC-MSCs' transcriptome and determine if pregnancy-related complications (preeclampsia and chorioamnionitis) alter their therapeutic potential. Single-cell RNA sequencing (scRNA-seq) was used to compare the transcriptome of UC-MSCs derived from five term donors, 16 preterm donors, and human neonatal dermal fibroblasts (HNDFs, control cells of mesenchymal origin), and correlated with their therapeutic potential in experimental BPD. Using publicly available neonatal lung single-nuclei RNA sequencing data, we also determined putative communication networks between UC-MSCs and resident lung cell populations. Most UC-MSCs displayed a similar transcriptome despite of their pregnancy-related conditions and mitigated hyperoxia-induced lung injury in newborn rats. Conversely, HNDFs, one term and two preeclampsia preterm UC-MSC donors exhibited a distinct transcriptome enriched in genes related to fibroblast function and senescence and were devoid of therapeutic benefit in hyperoxia-induced BPD. Conversely, therapeutic UC-MSCs displayed a unique transcriptome active in cell proliferation and distinct cell-cell interactions with neonatal lung cell populations, including NEGR and NRNX pathways. Term and preterm UC-MSCs are lung protective in experimental BPD. scRNA-seq allows to identify donors with a distinct UC-MSC transcriptome characteristic of reduced therapeutic potential.