The effect of HSA-deficiency on B-cell maturation. (A) B-cell maturation in BM is schematically divided into stages A-F according to Hardy et al6 and is based on the regulated expression of the surface markers CD45, CD43, BP1, CD24, IgM, and IgD. (B) The cellular pools size for each maturation stage is depicted by bars representing the mean % of total BM cells in 20 HSA-sufficient (▪) and 24 HSA-deficient (□) mice.