Isolation of a non-collagenous reticulin component and its primary characterization.

A reticulin component has been extracted from the saline insoluble residue of pig renal cortex and liver by a distilled water dispersion method. The water dispersed component, that could be precipitated by addition of NaCl up to 0·15 mol/l, was proved to be a protein distinct from collagen in that it contained no hydroxyproline and 9% glycine. The carbohydrate content was 4%, consisting mainly of galactose and mannose. The protein showed an affinity for the silver impregnation method, as used for reticulin. Antibodies to it, raised in rabbits, showed typical anti-reticulin staining by immunofluorescent techniques. It is suggested therefore that this protein, having peculiar solubility characteristics, may be a significant, non-collagenous component of reticulin.