The invention relates to methods and reagents for the treatment of immunological diseases. In particular, the invention relates to isoforms of the C4b-binding protein (C4BP) lacking beta chains as well as to fragments and peptides derived thereof and to the uses of these polypeptides for the treatment of immunological diseases such as immunoinflammatory disease, sepsis, an autoimmune disease, transplant rejection, graft-versus-host disease and a hypersensitivity disease. Moreover, the invention relates also the use of factor H for the treatment of immunological diseases. In addition, the invention relates to tolerogenic dendritic cells obtained using the C4BP isoform lacking beta chain, the peptides and fragments thereof and factor H and to the therapeutic uses of said cells.
