Method and apparatus for preparing an acellular red blood cell substitute.

A highly conserved, immunologically accessible antigen at the surface of Neisseria meningitidis organisms. Immunotherapeutic prophylactic and diagnostic compositions and methods useful in the treatment, prevention and diagnosis of Neisseria meningitidis diseases. A proteinase K resistant Neisseria meningitidis surface protein having an apparent molecular weight of 22 kDa, the corresponding nucleotide and derived amino acid sequences (SEQ ID N0:l, NO:3, NO:5, and NO:7: SEQ ID NO:1, NO:4, NO:6, and N0:8), recombinant DNA methods for the production of the Neisseria meningitidis 22 kDa surface protein, and antibodies that bind to the Neisseria meningitidis 22kDa surface protein.