Human endogenous retrovirus W envelope protein (HERV-W Env) (HERV-W Env)

Human endogenous retrovirus W envelope protein (HERV-W Env) is a protein derived from ancestral retroviral DNA integrated into the human genome millions of years ago. While one copy (Syncytin-1) has been co-opted for physiological use in placental development, a pathogenic variant known as MSRV-Env is abnormally expressed in patients with neurodegenerative and autoimmune disorders. This protein acts as a potent pro-inflammatory agonist of Toll-like receptor 4 (TLR4) on microglia and macrophages, driving a cascade of chronic inflammation and neurodegeneration. In the central nervous system, HERV-W Env directly inhibits the maturation of oligodendrocyte precursor cells, which prevents the repair of myelin sheaths in diseases like Multiple Sclerosis. Therapeutic intervention focuses on neutralizing this protein using monoclonal antibodies, such as temelimab, to halt the underlying disease progression without suppressing the patient's normal immune system. [Source: GeNeuro; PubMed PMID: 31308472, 25206364; UniProt: P61550]

Other names

Multiple sclerosis-associated retrovirus envelope proteinMSRV-EnvSyncytin-1 (physiologic homolog)ERVWE1 envelope proteinPathogenic HERV-W envelope protein (p-HERV-W Env)

Neutralization of the pathogenic HERV-W Env protein by a monoclonal antibody to prevent its interaction with Toll-like receptor 4 (TLR4), thereby reducing chronic neuroinflammation and promoting endogenous remyelination.