CD163(+) red pulp macrophages interact with marginal metallophilic macrophages during blood-stage malaria to maintain splenic architecture.

CD163 high red pulp macrophages, originating from yolk sac progenitors, are rapidly depleted during blood-stage malaria and are essential for maintaining splenic architecture.

• Why it matters: Understanding the development and long-term dynamics of splenic macrophage populations is crucial for insights into immune responses and tissue integrity during infections like malaria, yet these processes are not fully characterized.
• What they did: The study used fate-mapping models, single-cell RNA sequencing, and genetic mouse models to identify a distinct CD163 high RPM population that is self-maintaining and vital for spleen structure, and observed its depletion during malaria.
• The result: Loss of CD163 high RPMs impairs marginal zone integrity and disrupts macrophage crosstalk, suggesting that their sustained depletion rewires splenic architecture and immune interactions long after infection clearance.