The cellular lining of a continuous fluid compartment: an interstitial cell atlas

Interstitial populations and compartments map many-to-many, which is why marker sets developed in one organ transfer poorly to another. AbstractBackground. No compartment of the interstitium is lined by a single cell population, and no population is confined to one compartment. That is the structural reason marker sets developed in one organ transfer poorly to another, and it follows from the criterion used here to decide what belongs in an interstitial cell atlas: a cell qualifies if it sets the mechanical or transport properties of a fluid-conducting interstitial compartment. Findings. Fifteen stromal and interstitial populations are assembled on that basis, spanning fascia, vasculature, lymphoid tissue, gut, meninges, liver and synovium, each with its positive and discriminating negative markers and each closing on what would exclude it. The populations are pinned in an openly deposited interactive model. Conclusions. The recurring nomenclature collisions between these populations are set out as a specification for the cross-tissue reference the field still lacks. Preprint. Not peer reviewed. This paper and its companion on Interstitial Hydraulic Gating together supersede the earlier combined preprint at doi:10.5281/zenodo.22207857.