CD40LG and thymoma: In 1993, Matthes and colleagues used healthy PB B cells—co-cultured with mouse thymoma cells expressing CD40 ligand (CD40L) and/or supernatant from stimulated human T cells to simulate human T cell help [20]—to demonstrate that activated human B cells can produce TNFα, IL-6, tumor growth factor (TGF)β and IL-10.