CD44H LOCALIZATION IN PRIMARY OPEN-ANGLE GLAUCOMA

PURPOSE. Primary open-angle glaucoma (POAG) is associated with a decre ased content of hyaluronan in the trabecular meshwork and in the juxta canalicular connective tissue. Ln this study, the authors examined sel ected regions of the anterior segment to localize and determine the co ntent of CD44H, a transmembrane multifunctional glycoprotein and the p rincipal receptor of hyaluronan. METHODS. Sections of ethanol-fixed an terior segments of six POAG and six: normal postmortem eyes were analy zed by immunostaining with and without the nonionic detergent Triton X -100, using the CD44H monoclonal antibody, and the avidin/biotin compl ex. They were visualized by Vector VIP substrate and were quantitated by computer-aided color image analysis. RESULTS. CD44H was expressed i n all regions. Statistically significant decreased content of CD44H wa s observed in the POAG regions compared with normal regions-ciliary mu scle (P < 0.001), ciliary stroma (P < 0.001), anterior iris (P < 0.05) , iris root (P < 0.05), and trabecular meshwork (P < 0.05)-and in a su bgroup of nonlaser POAG juxtacanalicular connective tissue (P < 0.05) and trabecular meshwork (P < 0.01). In sections treated with Triton X- 100 a further increase in immunostaining was observed in normal eyes. As evidenced by scattergram plots of the ciliary body stroma region of the change in the optical density of CD44H between pretreatment with Triton X-100 and without Triton X-100 (y axis) versus the optical dens ity of CD44H without Triton X-100 (x axis), individual cases of POAG w ere separated from normals. CONCLUSIONS. These results indicate that C D44H may represent a marker of POAG and an etiologic factor in the POA G disease process.