In situ (mRNA) hybridization of tonsil sections with ephrin-A4 probe and control probe.

(A, B) Overview of a germinal center (GC) and extrafollicular area; objective ×25. (C, D) Close-up of a germinal center with follicular mantle (FM) zone; objective ×40. (E, F) Close-up of an extrafollicular (EF) area; objective ×40. Panels A, C, and E show the ephrin-A4 Dig-labeled probe, and panels B, D, and F, the control Dig-labeled probe. Brown staining shows ephrin-A4 mRNA hybridization in the GC and EF areas.