Significant differences in polar lipids associated with chronic blepharitis

Purpose. Our recent investigations focus on the relationship between human eyelid meibomian gland lipids and chronic blepharitis disease signs. As a continuation of this research, we have analyzed the polar lipids in meibum from patients in disease groups in order to determine significant group differences in polar lipids. Methods. Lipid types from individual meibum samples were separated by TLC and the polar lipid fraction was fractionated by HPLC with UV detection of individual polar Hpids. Résulta. Two polar Hpids were significantly associated with chronic blepharitis disease groups. Thus a phospholipid (less polar than phosphatidylethanolamine) was significantly greater (p<.02) in the primary meibomian keratoconjunctivitis (MKC) group than in normals. Also a cerebroside was significantly lower (p<.05) in the mixed staphylococcal-seborrheic (MIX) group than in normals. Finally, another polar lipid was higher in the secondary meibomianitis (2MEIB) and meibomian seborrhea (MBSB) groups, but in this investigation they were not significantly different (p .05) from normals. However, utilizing just three polar lipids, the groups MKC, MBSB and SBBL (seborrheic blepharitis) were significant different p<.03) from each other. Conclusion. We found a significant association between one chronic blepharitis disease group (MKC) and high levels of a specific polar lipid; whether this difference itself contributes to all meibum and tear film lipid layer abnormalities is unlikely since we have also observed distinct differences in unsaturated fatty acids in phospholipids and wax esters in this (MKC) group. The significance of polar lipids with respect to the other disease groups will be determined in more detailed investigations. We are currently characterizing the polar lipids in order to identify each and better understand their function in the tear film lipid layer. Supported by Research to Prevent Blindness and NIH EY03650. None.