CD40LG and B-cell chronic lymphocytic leukemia: This idea is supported by a previous study emphasizing how the functional maturity of a protein is not necessarily defined by its degree of glycosylation: Krysov et al. found that despite the mannosylated, so-called “immature” nature of the IgM μ chain expressed in chronic lymphocytic leukemia samples, increased expression of this partial glycoform—which could be induced by persistent antigen exposure—retained the same functional capabilities as its fully glycosylated, “mature” counterpart [46].