Within the NMDAR-antibody encephalitis patients, the 79/285 OT-associated serum samples showed a higher frequency of serum NR1-IgA [OR = 3.11 (CI 1.75–5.38), P < 0.0001, two-tailed Fisher’s exact test] and less frequent serum NR1-IgM [OR = 0.48 (CI 0.28–0.85), P = 0.011, two-tailed Fisher’s exact test; Fig. 1B]. Here, CD40LG is linked to viral encephalitis.