NMDAR IgA and IgM antibodies have been found in patients with progressive cognitive dysfunction and dementia (Pruss et al. 2012a; Doss et al. 2014), and IgM antibodies have been identified in cases of bipolar affective disorder and psychosis (Choe et al. 2013; Hammer et al. 2014). Here, CD40LG is linked to bipolar disorder.