GTX65635-pro CD40L protein (multimeric) does not need an enhancer to induce B cells activation. Method: PBL cells were incubated in 96-well plates (2x10⁵ cells/well in 100μl RPMI supplemented with 10% FCS) for 24 hours at 37ºC with the indicated concentration of CD40L (multimeric) or CD40L in the presence and absence of 1μg/ml Enhancer. Cells were washed with PBS and stained with CD86-PE antibody and CD19-FITC antibody, and then analyzed by flow cytometry.