Richter, J. R. | bioRxiv Science

bioRxiv2026

HS3ST1 regulates pulmonary inflammation and is a determinant of clinical outcomes after trauma and hemorrhagic shock

Mechanisms that promote organ injury after trauma and hemorrhagic shock (T/HS) remain poorly defined. Endothelial heparan sulfates with a 3-O-sulfate (3-OS) modification, controlled by the HS3ST1 gene, have anticoagulant and anti-inflammatory properties through their interaction with antithrombin. Our objective was to determine whether HS3ST1 deficiency drives organ injury and poor outcomes after T/HS. Hs3st1-/- and wild-type (WT) mice were subjected to T/HS followed by resuscitation with lactated ringers (LR) or fresh frozen plasma (FFP). While no differences were observed between WT and Hs3st1-/- LR resuscitated mice, lung injury and leukocyte infiltrates were significantly increased in FFP resuscitated Hs3st1-/-compared to WT mice. In vitro, leukocyte slow rolling and adherence was increased in HS3ST1 KO compared to WT cells. Among 472 T/HS patients, of which 31 (7%) were homozygous for the rs16881446 variant allele (GG), the number of ventilator free days was lower, and mortality was significantly higher in AG and GG patients. The rs16881446 genotype was independently associated with mortality. In conclusion, HS3ST1 deficiency mitigates organ protection from FFP resuscitation, partly through mediating EC:leukocyte engagement, and predicts mortality after T/HS. These findings identify a novel therapeutic target and prognostic tool that can be leveraged towards improved risk stratification after trauma.

cell biology↗

bioRxiv2026

Plasma regulates homeostatic pulmonary endothelial signaling to mitigate vascular leak following polytrauma and hemorrhagic shock

IntroductionIn hemorrhagic shock, plasma resuscitation preserves vascular integrity and protects against trauma-induced coagulopathy and organ injury. Despite demonstrated clinical benefit, the endothelial mechanisms underlying plasma resuscitation remain incompletely defined. This study investigated endothelial-specific responses to plasma resuscitation to identify targetable pathways that promote vascular repair after traumatic injury. MethodsA murine model of severe polytrauma-hemorrhagic shock (PT/HS) with demonstrable vascular endotheliopathy by 24 hours was used to compare pulmonary vascular endothelial cell (EC) responses to resuscitation with lactated Ringers (LR) relative to fresh frozen plasma (FFP). Whole blood was collected for inflammatory biomarker analysis, and pulmonary vascular leak was quantified by dextran extravasation. Pulmonary EC glycocalyx (eGC) structure was assessed by transmission electron microscopy and immunofluorescence. Spatial transcriptomic profiling of pulmonary ECs was performed using a GeoMx Digital Spatial Profiler. Key transcriptomic findings related to mitochondrial biogenesis were validated by immunostaining and by treating primary human lung EC with FFP or LR. ResultsAt 24 hours after injury, FFP reduced systemic inflammatory cytokines, pulmonary innate immune cell infiltration, and PT/HS-induced vascular leak compared to LR. Plasma levels of syndecan-1, syndecan-4, and hyaluronan were decreased, consistent with enhanced pulmonary eGC expression. Although few differences in eGC-related genes were detected, pathway analysis revealed enrichment of cellular bioenergetics and metabolic recovery pathways in ECs after FFP, whereas LR was associated with oxidative stress and inflammatory signaling. FFP enhanced mitochondrial content in pulmonary EC after PT/HS and in treated human EC compared to LR-treated controls. ConclusionsFFP resuscitation after PT/HS reduces systemic inflammation and preserves pulmonary vascular barrier function, potentially through promotion of mitochondrial signaling, metabolic recovery, and endothelial stress regulation.

cell biology↗