Fig. 3.
Immunohistochemical staining results of the lymph node. (A) MUM-1/IRF4-stain highlighting sheets of germinotrophic plasmablasts. (B) Epithelial membrane antigen–stain demonstrating confluent aggregation of plasmablasts with sinusoidal pattern. (C) Human herpes virus 8 encoded latency associated nuclear antigen 1 highlighting the atypical plasmablasts. (D) In situ hybridization for Epstein-Barr virus (EBV) encoded ribonucleic acids showing coinfection of EBV in the atypical plasmablasts.