The lipids of chalazia.

The tissue contents of chalazia taken from five individuals were extracted for lipids and analyzed by TLC and GLC. Lipids found were sterol esters 9%, wax esters 0%, triacyl glycerols 4%, free cholesterol 11%, free fatty acids 2%, unidentified nonpolar material 3%, ceramides 7%, cerebrosides 3%, phosphatidyl ethanolamine 12%, phosphatidyl choline 20%, sphingomyelin 4%, lysolecithin 4%, unidentified polar material 18.0%. GLC of the sterol esters gave peaks corresponding to the C14, C16, C18 and C20 normal fatty acid esters of cholesterol. The free fatty acids were also of the normal kind. Thus, the lipids of chalazia contents show little similarity to the lipids of the meibomian gland. The latter has a large component of sterol esters and wax esters. Also the fatty acids of all the meibomian gland ester lipids have significant amounts of iso- and anteisobranching in contrast to the chalazia lipids. Chalazia lipids more closely resemble the lipids of membranes of phagocytic cells with a large cholesterol content.