Enhanced Fatty Acid Synthesis Leads to Subset Imbalance and IFN-γ Overproduction in T Helper 1 Cells
S. Iwata, Mingzeng Zhang, Hao He, Gulzhan Trimova, Maiko Hajime, Yusuke Miyazaki, Naoaki Ohkubo, Yurie Satoh Kanda, Yasuyuki Todoroki, Hiroko Miyata, Masanobu Ueno, Atsushi Nagayasu, Shingo Nakayamada, Kei Sakata, Yoshiya Tanaka
Abstract
Recent reports have shown the importance of IFN-γ and T-bet + B cells in the pathology of SLE, suggesting the involvement of IFN-γ-producing T-bet + CD4 + cells, i.e., Th1 cells. This study determined the changes in Th1 subsets with metabolic shift and their potential as therapeutic targets in SLE. Compared with healthy donors, patients with SLE had higher numbers of T-bet hi CXCR3 lo effector cells and T-bet + Foxp3 lo non-suppressive cells, which excessively produce IFN-γ, and lower number of non-IFN-γ-producing T-bet + Foxp3 hi activated-T reg cells. These changes were considered to be involved in treatment resistance. The differentiation mechanism of Th1 subsets was investigated in vitro using memory CD4 + cells obtained from healthy donors and patients with SLE. In memory CD4 + cells of healthy donors, both rapamycin and 2-deoxy-D-glucose (2DG) suppressed T-bet + Foxp3 - cells, and induced T-bet + Foxp3 +(lo/hi) cells. Rapamycin induced IFN-γ-producing T-bet + Foxp3 lo cells accompanied with enhanced lipid metabolism, whereas 2DG induced IFN-γ-non-producing T-bet + Foxp3 hi cells. In memory CD4 + cells of SLE patients, inhibition of fatty acid synthesis, but not β-oxidation, suppressed IFN-γ production, and up-regulated of Foxp3 expression in T-bet + Foxp3 + cells. Metabolic regulators such as fatty acid synthesis inhibitors may improve the pathological status by correcting Th1 subset imbalance and overproduction of IFN-γ in SLE.