CHMP5 is an accessory component of the ESCRT-III complex that functions in diverse cellular processes beyond its traditional role in multivesicular body formation. The protein is essential for Rab11a-positive exosome biogenesis, selectively promoting formation of intraluminal vesicles in recycling endosomes without affecting ubiquitin-mediated protein degradation in late endosomes 1. CHMP5 forms functionally distinct ESCRT-III polymers from the core CHMP4/Snf7 subunit, with segregated localization and different recruitment dynamics during cellular processes 2. In T-cell signaling, CHMP5 regulates TCR surface expression and downstream signaling activation, likely through receptor recycling or degradation mechanisms 3. The protein also plays protective roles in cell survival, blocking ferroptosis through ESCRT-III-dependent membrane repair 4 and inhibiting chondrocyte apoptosis in osteoarthritis via NF-κB pathway modulation 5. Clinically, CHMP5 demonstrates oncogenic properties in T-cell acute lymphoblastic leukemia by mediating BRD4 and p300 recruitment to transcriptional enhancers 6. The protein is required for EGFR degradation in MVB sorting pathways, though it paradoxically increases HIV-1 particle release when depleted 7.