IGFBP6 orchestrates antiinfective immune collapse in murine sepsis via prohibitin-2-mediated immunosuppression.

Summary

A multicenter, cross-age cohort anchored mechanistic study identifies IGFBP6 as a regulator of sepsis outcomes and delineates an IGF-independent IGFBP6–PHB2–STAT1/Akt pathway that suppresses chemotaxis and macrophage bactericidal function. Genetic and pharmacologic interventions restored CCL2 expression, bacterial clearance, and survival in septic mice, nominating IGFBP6 as both biomarker and therapeutic target.

Key Findings

• IGFBP6 identified as a diagnostic/prognostic regulator across multicenter, cross-age sepsis cohorts.
• Mechanism: IGFBP6 binds PHB2 (IGF-independent), inducing PHB2 phosphorylation, disrupting STAT1 activation and CCL2 transcription, impairing macrophage chemotaxis.
• PHB2 silencing or STAT1 activation (2-NP) restored CCL2, enhanced bacterial clearance, and improved survival in septic mice.
• IGFBP6 suppresses macrophage Akt phosphorylation, reducing ROS/IL-1β and phagocytosis; effects reversed by the Akt agonist SC79.

Clinical Implications

IGFBP6 could enable risk stratification and serve as a drug target; modulating the IGFBP6–PHB2–STAT1/Akt axis may restore host defense in sepsis. Clinical validation and early-phase trials are the next steps.

Limitations

• Clinical performance metrics (e.g., AUROC, thresholds) for IGFBP6 as a biomarker are not detailed in the abstract.
• Translational gap: dosing, safety, and timing for pathway modulation in heterogeneous human sepsis remain untested.

Future Directions

Prospective validation of IGFBP6 as a diagnostic/prognostic marker, PK/PD-driven development of modulators targeting PHB2–STAT1/Akt, and early-phase interventional trials in stratified sepsis populations.