Biology subjects

Morita, W.

Publications and source records attributed to Morita, W..

2 recordsLinked to original sources

bioRxiv2025

Pathologic profibrotic activation of distinct myeloid cell subsets in a model of impaired healing after anterior cruciate ligament reconstruction

Anterior cruciate ligament reconstruction (ACLR) may fail due to poor bone-to-tendon integration, yet the cellular mechanisms underlying this process remain incompletely understood. Using a murine model of ACLR, we show that host-derived immune cells are the primary drivers of early healing, while tendon graft-derived stromal cells also contribute at the tendon-bone interface. We developed a model of impaired post-ACLR healing by a surgical approach, that led to increased infiltration of immune cells at the tendon-bone interface, particularly CX3CR1+ monocytes/macrophages (MonoMacs). Single-cell RNA sequencing revealed dynamic monocyte-to-macrophage transitions, with an enrichment of fibrotic, mechanosensitive CX3CR1+ MonoMacs in the impaired healing model. These findings suggest that excessive recruitment or functional shifts in host-derived MonoMacs may disrupt normal healing dynamics. Our study identifies CX3CR1+ MonoMacs as a key cell population related to inferior bone-to-tendon healing after ACLR and potential therapeutic targets to improve surgical outcomes.

immunology↗

bioRxiv2025

Deep origins and distinct adaptations indicated for a glacial relict seal

Isolated populations of postglacial relicts are known from many regions and are typically found on mountains for terrestrial species and in lakes for aquatic species. Among the few aquatic mammalian relicts, the Saimaa ringed seal (Pusa hispida saimensis) has been landlocked in Lake Saimaa, Finland, for the last 10,000 years. Saimaa ringed seals show genetic, behavioral, and morphological differences to the other ringed seal subspecies, but the extent these differences stem from the end of the last glacial period remains unclear. Here, we demonstrate with comprehensive sampling and state-of-the-art genomic methods that the Saimaa ringed seals are much older than the lake they inhabit, having formed a separate evolutionary branch for at least 60,000 years. This deep evolutionary origin of the Saimaa ringed seals is further underscored by our ecomorphological analyses revealing adaptively distinct features in their dentition and tongue. Overall, glacial relicts, many threatened by extinction, may harbor a richer selection of evolutionary history than might be expected from their recent isolation history alone.

zoology↗