SDC1 and Hodgkins lymphoma: In the present experiments, IHC was used to examine a diverse variety of immune cell markers in HL biopsies, including CD3 (T cells), CD20 (B cells), CD14 (monocytes/macrophages), CD15 (granulocytes including neutrophils and eosinophils), CD56 (natural killer cells), and CD138 (plasma cells) (Fig. 2A).