The invention relates to a glycosylated polypeptide comprising an amino acid sequence being identical or homologous to at least a fragment of a mammalian, preferably a human protein, wherein said glycosylated polypeptide contains one or more sialylated O-glycans and wherein the glycosylated polypeptide shows an increased binding affinity to one or more SIGLECs, selected from SIG-5, SIG-7, SIG-8, and SIG-9 compared to the mammalian protein or fragment thereof. The invention further relates to composition comprising a first and a second polypeptide, wherein the first polypeptide is a glycosylated polypeptide containing one or more sialylated O-glycans and the second polypeptide contains an amino acid sequence homologous or identical to a second mammalian, in particular human protein, wherein compared to the second polypeptide the composition has an increased binding affinity to a SIGLEC selected from to one or more SIGLECs, selected from SIG-5, SIG-7, SIG-8, and SIG-9.