Effect of shark cartilage on the cytotoxic activity of NK cells immune system

Background: On the basis of traditional medicine Shark cartilage have been used in the treatment of cancer especially immune related cancers. Then, we hypotheses that shark cartilage contains immune stimulatory ingredients. Methods: The immune stimulatory effect of shark cartilage derived proteins on the cytotoxic activity of natural killer cells(NK cells) from healthy human peripheral blood mononuclear cells (hPBMN) was studied. Shark cartilage proteins were purified by ion-exchange chromatography and ultra filtration. The effect of each protein fraction on the modulation of cytotoxicity of NK cells, as effectors, against K562, as target cells, was assayed by enzymatic LDH test. Results: The results from cytotoxic assay of NK cells and SDS- Polyacrylamide gell electrophoresis of shark cartilage protein fractions indicated that AR10 fraction, containing proteins with molecular weight of about 14.5 KDa is the most active ingredients of shark cartilage. Conclusion: Shark cartilage contains a 14.5 KDa protein that modulates NK cells activity of human immune system.