Disclosed are human interleukin-1 .beta. converting enzyme like apoptosis
proteases-3 and 4 and DNA (RNA) encoding such polypeptides. Also provided
is a procedure for producing such polypeptides by recombinant techniques
and antibodies and antagonists against such polypeptides. Also provided
are methods of using the polypeptides, for example, as an antitumor agent,
and antiviral agent, and antibodies and antagonists against such
polypeptides for example, for treating Alzheimer's disease, Parkinson's
disease, rheumatoid arthritis and head injury.