In human neuroblastoma cell lines (BE(2)-C and SH-SY5Y), we could reduce the endogenous levels of tau by reducing TYK2 function, either by infection with lentivirus containing a short hairpin RNA (shRNA) that suppresses TYK2 expression or by enzymatic inhibition of TYK2 using a small molecule (deucravacitinib; Extended Data Fig. 1a,b). The gene discussed is TYK2; the disease is infection.