Studies on histidine-rich polypeptides (histatins) in human saliva

1.A simple and rapid isolation of histatins from human saliva。Histidine-rich polypeptides(histatin1，3and5)from human whole saliva were isolated by affinity chromatography on heparine-ultrogel and reverse-phase high performance liquid chromatography(Hplc)。About6毫克of the mixture of histatins were obtained from 100ml of the saliva.Histatins1，3and5contained38，32and24amino acid residues，and had molecular weight of 4929，4063，and3037，respectively.They contained7 residues of histidine in their molecules.2。Histamine release induced by histatins.Histatin3and5produced dose-related histamine release from isolated rat mast cells in the concentration range of 10-40m，respectively，and also histatin1ded in the range40-100m.This histamine release was temperature dependent and completed within10sec at 37°c.This relase was not accompanied by the leakage of lactate dehydrogenase from mast cells.Thus，it was suggested that the histatins caused the release of histamine by an exocytotic mechanism.3。Anti-endotoxin effect of histations.1)Histatins inhibited the gelation by endotoxin(LPS)on limulus reaction。2)Histatins reduced the inhibition by LPS of complement-induced hemolysis.3)histatins formed the precipitates with several lps in the agarose gel。

1. A simple and rapid isolation of histatins from human saliva. Histidine-rich polypeptides (histatin 1,3 and 5) from human whole saliva were isolated by affinity chromatography on heparine-ultrogel and reverse-phase high performance liquid chromatography (hplc). About 6 mg of the mixture of histatins were obtained from 100 ml of the saliva. Histatins 1,3 and 5 contained 38, 32 and 24 amino acid residues, and had molecular weight of 4929, 4063, and 3037, respectively. They contained 7 residues of histidine in their molecules.2. Histamine release induced by histatins. Histatin 3 and 5 produced dose-related histamine release from isolated rat mast cells in the concentration range of 10-40 m, respectively, and also histatin 1 ded in the range 40 - 100 m. This histamine release was temperature dependent and completed within 10 sec at 37゜c. This relase was not accompanied by the leakage of lactate dehydrogenase from mast cells. Thus, it was suggested that the histatins caused the release of histamine by an exocytotic mechanism.3. Anti-endotoxin effect of histations. 1) Histatins inhibited the gelation by endotoxin (LPS) on limulus reaction. 2) Histatins reduced the inhibition by LPS of complement-induced hemolysis. 3) histatins formed the precipitates with several lps in the agarose gel.