The present invention is related to antibodies directed to the antigen properdin and uses of such antibodies. In particular, in accordance with the present invention, there are provided fully human monoclonal antibodies directed to the antigen properdin. Nucleotide sequences encoding, and polypeptides comprising, heavy and light chain immunoglobulin molecules, particularly sequences corresponding to contiguous heavy and light chain sequences spanning the framework regions and/or complementarity determining regions (CDR's), specifically from FR1 through FR4 or CDR1 through CDR3, are provided. Hybridomas or other cell lines expressing such immunoglobulin molecules and monoclonal antibodies are also provided.