Large-scale purification of the synthetic peptide fragment 163-171 of human interleukin-beta by multi-dimensional displacement chromatography.

Multi-dimensional chromatography has been used successfully in the displacement mode for the purification of the synthetic peptide H-Val-Gln-Gly-Glu-Glu-Ser-Asn-Asp-Lys-OH, the fragment 163-171 of human interleukin-beta. This peptide can mimic several of the in vivo and in vitro immunostimulatory activities of the entire protein, except for the inflammatory effect. A large-scale procedure has been developed to purify the synthetic peptide by reversed-phase (RP) and ion-exchange (IE) displacement chromatography (DC) in a single run without any pretreatment. Masses from 100 mg to about 35 g of the unpurified compounds synthesized by a solid-phase technique on a Merrifield-type resin and obtained by acidolytic cleavage from the solid support, can be purified in this way. In the RP-DC mode the carrier and the displacer were aqueous solutions of 0.1% trifluoroacetic acid and 50 mM benzyltributylammonium chloride, respectively, whereas in the IE-DC mode the carrier was water and the displacer 50 mM ammonium citrate solution. RP-DC and IE-DC were also performed in series by directing the effluent of the RP column onto the IE column. Peptide purities and recoveries greater than 96 and 90%, respectively, were obtained.