Follicular helper T (T FH ) cells are critical for germinal center (GC) formation and are responsible for effective B cell-mediated immunity; metabolic signaling is an important regulatory mechanism for the differentiation of T FH cells. However, the precise roles of hypoxia inducible factor (HIF) 1α-dependent glycolysis and oxidative phosphorylation (OXPHOS) metabolic signaling remain unclear in T FH cell differentiation. Herein, we investigated the effects of glycolysis and OXPHOS on T FH cell differentiation and GC responses using a pharmacological approach in mice under a steady immune status or an activated immune status, which can be caused by foreign antigen stimulation and viral infection. GC and T FH cell responses are related to signals from glycolytic metabolism in mice of different ages. Foreign, specific antigen-induced GC, and T FH cell responses and metabolic signals are essential upon PR8 infection. Glycolysis and succinate-mediated OXPHOS are required for the GC response and T FH cell differentiation. Furthermore, HIF1α is responsible for glycolysis- and OXPHOS-induced alterations in the GC response and T FH cell differentiation under steady or activated conditions in vivo . Blocking glycolysis and upregulating OXPHOS signaling significantly recovered T FH cell differentiation upon PR8 infection and ameliorated inflammatory damage in mice. Thus, our data provide a comprehensive experimental basis for fully understanding the precise roles of HIF1α-mediated glycolysis and OXPHOS metabolic signaling in regulating the GC response and T FH cell differentiation during stable physiological conditions or an antiviral immune response.
【저자키워드】 virus infection, B cell immunity, Glycolysis, GC responses, HIF1α, oxidative phosphorylation, Follicular helper T cell, T cell differentiation, infectious inflammation,