Because both, its particular isotype composition and the chemical treatments during manufacturing might affect the immunomodulatory capacity of an IVIg preparation, our aim was to explore in vitro the immunomodulatory capacity of Pentaglobin, an IVIg enriched in IgM/IgA (IVIgGMA) and Vigam, an IVIg preparation with more than 95% of IgG (IVIgG) in CLL. Here, CD40LG is linked to B-cell chronic lymphocytic leukemia.