Researchers in Belgium, Russia, Hungary and the U.S. (Whittemore Peterson Institute) reported results of a preliminary analysis of de-identified gut tissue obtained from 12 patients meeting Canadian and Fukuda definitions for ME/CFS and CFS and eight control subjects. Tissue samples were obtained during clinical diagnostic procedures and limited information was available about the subjects. Eight of 12 individuals with ME/CFS displayed immunoreactivity to human endogenous retroviral (HERV) proteins localized to cells with plasmacytoid dendritic cell characteristics. No immunoreactivity was observed in control tissue.  The authors suggest that “the prospect of an involvement of HERVs and plasmacytoid dendritic cells in ME pathology provides an opportunity for more directed studies into the immune dysregulation associated with this disease.” A larger and properly controlled study is needed. (In Vivo)