title: Microglial CD206 Gene Has Potential as a State Marker of Bipolar Disorder.
abstract: The pathophysiology of bipolar disorder, especially the underlying mechanisms of the bipolarity between manic and depressive states, has yet to be clarified. Microglia, immune cells in the brain, play important roles in the process of brain inflammation, and recent positron emission tomography studies have indicated microglial overactivation in the brain of patients with bipolar disorder. We have recently developed a technique to induced microglia-like (iMG) cells from peripheral blood (monocytes). We introduce a novel translational approach focusing on bipolar disorder using this iMG technique. We hypothesize that immunological conditional changes in microglia may contribute to the shift between manic and depressive states, and thus we herein analyzed gene profiling patterns of iMG cells from three patients with rapid cycling bipolar disorder during both manic and depressive states, respectively. We revealed that the gene profiling patterns are different between manic and depressive states. The profiling pattern of case 1 showed that M1 microglia is dominant in the manic state compared to the depressive state. However, the patterns of cases 2 and 3 were not consistent with the pattern of case 1. CD206, a mannose receptor known as a typical M2 marker, was significantly downregulated in the manic state among all three patients. This is the first report to indicate the importance of shifting microglial M1/M2 characteristics, especially the CD206 gene expression pattern between depressive and manic states. Further translational studies are needed to dig up the microglial roles in the underlying biological mechanisms of bipolar disorder.
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University , Fukuoka , Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ohgidani
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; Innovation Center for Medical Redox Navigation, Kyushu University, Fukuoka, Japan.
authors.forename: Takahiro A
authors.initials: TA
authors.lastname: Kato
authors.affiliation: Department of Psychiatry, Graduate School of Medical Sciences, Saga University , Saga , Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Haraguchi
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University , Fukuoka , Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Matsushima
authors.affiliation: Department of Psychiatry, Graduate School of Medical Sciences, Saga University , Saga , Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Mizoguchi
authors.affiliation: Department of Psychiatry, Graduate School of Medical Sciences, Saga University , Saga , Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Murakawa-Hirachi
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University , Fukuoka , Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Sagata
authors.affiliation: Department of Psychiatry, Graduate School of Medical Sciences, Saga University , Saga , Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Monji
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University , Fukuoka , Japan.
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Kanba
keywords: CD206; M1/M2 polarization; bipolar disorder; induced microglia-like (iMG) cells; microglia; rapid cycling; state marker; translational research