Microtubule-associated protein tau (MAPT) oligomer (Tau oligomer)

Microtubule-associated protein tau (MAPT) is a phosphoprotein that primarily functions to stabilize microtubules in the neuronal cytoskeleton, which is essential for axonal transport and structural integrity (UniProt: P10636). In neurodegenerative diseases known as tauopathies, such as Alzheimer's disease and Frontotemporal dementia, tau undergoes pathological hyperphosphorylation and misfolding, leading to the formation of soluble toxic oligomeric aggregates (PubMed: 32814900). These oligomers are considered the most neurotoxic species, as they impair synaptic plasticity, induce neuroinflammation, and facilitate the spread of pathology across brain regions via a prion-like mechanism (PubMed: 29371435). Therapeutic strategies targeting these aggregates include monoclonal antibodies like Bepranemab and E2814, which are designed to sequester extracellular tau and block its cell-to-cell propagation (ClinicalTrials.gov). Current drug development efforts focus on identifying specific epitopes unique to toxic oligomers to avoid interfering with the physiological functions of monomeric tau (PubMed: 31160304).

Other names

Tau toxic oligomersTau protofibrilsSoluble tau aggregatesMAPT oligomersTau seedsTau toxic oligomeric aggregates

The primary mechanism of action for drugs targeting tau oligomers is passive immunotherapy, where monoclonal antibodies bind to specific epitopes on extracellular tau to prevent its internalization and subsequent template-directed misfolding in healthy neurons (PubMed: 30305116). Other mechanisms include small molecule aggregation inhibitors that stabilize the monomeric form of tau or disrupt the formation of oligomeric intermediates, and antisense oligonucleotides (ASOs) designed to reduce the expression of the MAPT gene to lower the total concentration of tau protein (PubMed: 31160304).