The present invention provides antibodies and antigen-binding fragments thereof that bind specifically to BlyS, immunoglobulin chains thereof, variants thereof and method of use thereof, e.g., for the treatment or prevention of inflammatory and/or immune diseases such as systemic lupus erythramatous as well as polynucleotides encoding the immunoglobulin chains of such antibodies and fragments. Methods for the recombinant expression of immunoglobulin chains are also part of the present invention.
