Fig. 5.

Blocking ICOSL does not inhibit the RF B-cell response to IgG2a antichromatin Abs. BALB/c mice were killed on day 6 after transfer of AM14 sd-Tg B cells and administration of PL2-3 along with ICOSL blocking or control Ab. Representative flow cytometry plots are shown, gated as described in Fig. 1A. (A and B) 4–44⁺ surface and intracellular double-positive cells. (C) Fraction of 4–44⁺ cells that had lost expression of IgD. (D–G) Splenic 4–44⁺ AFCs of IgM (D), IgG2a (E), IgG2b (F), or anti-IgA (G) isotype. Data are compiled from two independent experiments.