CD40LG and autoimmune encephalitis: Autoimmune encephalitis could be ruled out by neurologists upon getting negative results of anti-aquaporin4 IgG Ab, anti-monosialoganglioside (GM1) Ab, and anti-ganglioside Ab IgG panel (anti-GQ1b IgM, anti-GD1 B IgM) tests from peripheral blood serum samples.