PDCD1 and viral encephalitis: Then, bioinformatics algorithms uncovered the probable miR-2467-5p binding sites in the 3'untranslated region (UTR) of CSF3' and PDCD1' mRNA (Fig. 6M), and a negative correlation was found between PDCD1 expression and CCL15 expression in the serum of LGI1 encephalitis patients (r = −0.546, p = 0.013) (Additional file 9: Fig. S9).