TLR2 and Alzheimer disease: Polymorphisms in Pattern Recognition Receptors (PRRs) such as Toll-Like Receptor 2 (TLR2) - the main receptor responsible for recognizing staphylococcal ligands, Nucleotide - binding oligomerization domains 1 (NOD1) and NOD2 are associated with AD in a way that enables S. aureus overgrowth (80).