The Extracellular Domains of IgG1 and T Cell-Derived IL-4/IL-13 Are Critical for the Polyclonal Memory IgE Response In Vivo
Fig 8
N. brasiliensis-elicited memory B cells depend on IL-4/IL-13 secretion from CD4+ T cells for IgE secretion but not for expansion.
(A) Outline of transfer experiment referring to data in B, C, and D. B cells from memory IgHa/Ly5.2 and naïve IgHb/Ly5.1 mice were sorted and transferred into Rag1–/–mice without or with sorted WT or 4-13Tko memory T cells. Mesenteric LN and serum were analyzed 12 d after N. brasiliensis infection of Rag1–/–recipient mice. (B) Percentage and total numbers of B220+ cells originated from the memory (Ly5.2, black bars) or naïve (Ly5.1, grey bars) mice in Rag1–/–mice that also received either 4-13Tko or WT memory T cells, or no T cells gated as indicated in S12A Fig. (C) Expression of CD38 on B220+ cells from memory mice (Ly5.2+, black bars) or naïve mice (Ly5.2−, grey bars) without or with cotransfers of T cells from 4-13Tko or WT memory mice gated as indicated in S12B Fig. (D) Bar graph shows IgE secreted from memory (detected as IgEa) or naive cells (detected as IgEb) in the serum of Rag1–/–mice that received either 4-13Tko or WT memory T cells. Data show the mean + SEM from 2–3 independent experiments and 4–8 mice per group. **p < 0.005 ***p < 0.001 by Student’s t test. n. d. = not detectable.