IL21 and infection: This model used a variety of conditions reported to generate ASCs from B cells (Ettinger et al., 2005; Lanzavecchia and Corti, 2014), with a focus on conditions that: (i) mimicked T cell help (IL-2, IL-21 ± CD40L); (ii) simulated infections, which are hypothesized triggers of NMO relapses (IL-1β, TNFα and toll-like receptor stimulation with R848) (Koga et al., 2011); and (iii) utilized cytokines already implicated in NMO (IL-6, BAFF, APRIL) (Kothur et al., 2016).