1IFN-α Modulates Memory Tfh Cells and Memory B Cells in Mice, Following Recombinant FMDV Adenoviral Challenge

• Published in: Frontiers in immunology Vol. 11; p. 701
• Main Authors: Duan, Xiangguo, Sun, Peng, Lan, Yaru, Shen, Chunxiu, Zhang, Xiaoyu, Hou, Shaozhang, Chen, Jian, Ma, Bin, Xia, Yuhan, Su, Chunxia
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 29.04.2020
• Subjects: foot-and-mouth disease recombinant adenovirus vaccine; IFN-α; immune memory; Immunology; memory B cell; memory Tfh cell
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2020.00701

Follicular helper T (Tfh) cells regulate high-affinity antibody production. Some findings have indicated that Tfh cells could be differentiated into memory cells. Here we have investigated the effects of IFN-α, as an adjuvant, on the generation of memory Tfh cell and memory B cell responses. The data showed that adenoviral vectors expressing: (i) foot-and-mouth disease virus (FMDV) VP1 proteins and porcine IFN-α, or (ii) porcine IFN-α alone, potently enhanced the generation of memory Tfh cells, especially the CCR7 l o memory Tfh subset. Upon rechallenge with FMD recombinant adenoviral vaccines, IFN-α enhances Tfh cells activity, rapidly upregulating their signature Bcl-6, CXCR5, and IL-21 markers. The results suggest that IFN-α enhances the levels of the transcription factor Bcl-6 within Tfh cells, potentially by regulating STAT1. Additionally, IFN-α substantially increased the number of IgG1 + and CD86 + memory B cells, which are responsible for inducing the rapid effector functions of memory Tfh cells after vaccine reactivation, establishing the close relationship between memory B cell and memory Tfh cell subsets. In brief, IFN-α enhances the potency of FMD recombinant adenoviral vaccines to induce memory Tfh and memory B cell responses, thus elevating serum antibody titers. IFN-α administration therefore represents an attractive strategy for enhancing responses to vaccination.