Polypeptide, process for preparing it, microorganism and pharmaceutical use.

摘要

A novel polypeptide having antitumor activity wherein the first 23 NH2-terminal amino acid sequence of its monomeric form is Ser-Arg-Thr-Pro-Ser-Asp-Lys-Pro-Val-Ala-His-Val-Val-Ala-Asn-Pro-Gln-Al a-Glu-Gly-Gln-L eu-Gln and which has the following characteristics: (a) a molecular weight of 17,000 +/- 1,500 as calculated from data obtained by SDS polyacrylamide electrophoresis; (b) an isoelectric point of 5.2 +/- 0.2 as determined by chromatofocusing; (c) a cytocidal activity against L-929 cells of 1 x 10<7> - 10 x 10<7> units/mg protein as defined hereinafter; and (d) ability to adsorb on a dye adsorption affinity carrier and preparation or purification thereof are disclosed. This novel type of polypeptide has excellent antitumor activities, and is obtained by use of the recombinant DNA technique, or by special purification from the culture of activated human machrophage or human macrophage-like cells.