J Immunol. 2025 Aug 7:vkaf184. doi: 10.1093/jimmun/vkaf184. Online ahead of print.
ABSTRACT
Human macrophages differ from their mouse counterparts in multiple metabolic pathways, surface protein expression, and transcription factor biology. Monocyte-derived macrophages (MDMs) from blood are generally used to study human macrophage biology in vitro. However, the use of MDMs as a human macrophage model is limited by donor-to-donor variability, total cell availability, preactivation effects, and relative resistance to genetic manipulation. Here, we explored stem cell-derived macrophages to study in vitro disease-relevant macrophage phenotypes. We compared induced pluripotent stem cell-derived macrophages (iDMs) with primary human stem cell-derived macrophages from cord blood-derived macrophages or bone marrow-derived macrophages (BMDMs) in their ability to elaborate tissue and disease-relevant phenotypes in comparison with conventional blood MDMs. Analyses of phenotypical and functional features revealed that iDMs were highly similar to cord blood-derived macrophages and BMDMs, and resembled MDMs. Importantly, all macrophages, and particularly iDMs adopted expected disease-relevant phenotypes in vitro when stimulated with disease-associated mediators. RNA sequencing analyses of in vitro macrophages stimulated with tissue relevant factors revealed that their transcriptomes mapped to human in vivo inflammatory conditions. Using this approach, we found a close correlation between stimulation and expected disease-association counterpart in vivo. In conclusion, we established a streamlined system to link stem cell-derived macrophage phenotypes to relevant macrophage phenotypes in disease states. Thus, enabling conditions for in vitro replication of complex human macrophage biology observed in single-cell RNA sequencing from human diseased tissue.
PMID:40795241 | DOI:10.1093/jimmun/vkaf184