the ifn-independent induction of ak activity was not dependent on the o-antigenic polysaccharide part of the lipopolysaccharide ( lps ) on the bacterial cell surface , because both smooth ( s ) strains with differing o-antigenic structures ( s-4,12 and s-6,7 ) and a rough ( re ) strain without o-antigen were effective inducers .
C0023810
lps
C0069180
o-antigen