both il 1-beta and a second 17-kda il 1 moiety with a pi of 5.0 ( il 1-alpha ) were also extracted from stimulated thp-1 cells and purified to homogeneity by sequential chromatography on sephacryl s-200 , ion exchange hplc , and hydroxyapatite hplc .
C0021755
il 1
C0600251
il 1-alpha