Molecular cloning and expression of cynomolgus monkey interleukin-1beta cDNA

The cynomolgus monkey cDNA encoding interleukin-1beta (IL-1beta) was molecularly cloned by the reverse transcription polymerase chain reaction from a cDNA library of adherent splenocytes stimulated with lipopolysaccharides. The sequence analysis showed that the monkey IL-1beta cDNA encodes a protein of 268 amino acids and displays a high degree (90%) of homology with the human counterpart. Substitution of amino acids resides mainly in the leader sequences of IL-1beta when compared with those of human IL-1beta. This cloned monkey IL-1beta cDNA was used to express in Escherichia coli as a fusion protein with thioredoxin and in insect cells infected with a recombinant baculovirus after molecular modification where monkey IL-1beta signal sequences were placed prior to the mature sequences of IL-1beta for efficient secretion in insect cells. Recombinant monkey IL-1beta expressed in both systems was shown to react with rabbit antihuman IL-1beta antiserum by Western blot analysis and to have the biological activity of IL-1beta in a bioassay.