The groups included B cells purified from follicular lymphoma biopsies; centrocytes, the non-cycling fraction of germinal center B cells, isolated ex vivo from tonsillar tissues; and activated B cells, isolated from peripheral blood samples and stimulated in vitro using a combination of IL-4, a-CD40, a-IgM, and a-IgD (Koues et al., 2015). This evidence concerns the gene IL4 and follicular lymphoma.