['Mutations in the MYOC gene coding for myocilin are associated with elevated intraocular pressure (IOP), and recombinant myocilin, produced in a prokaryotic expression system, has been reported to affect aqueous outflow facility. This study was conducted to test whether perfusion with a fragment of recombinant myocilin (containing the full-length olfactomedin domain), produced in a eukaryotic expression system, affects facility.', '293 EBNA cells were transfected by a vector containing the BM40 signal peptide, a human cDNA coding for myocilin, and a polyhistidine tag (HisTag) sequence. Recombinant protein was isolated by Ni-chelate chromatography, and characterized, and perfused into cultured anterior segments of human and porcine eyes.', 'Recombinant myocilin was secreted as a approximately 55-kDa intact protein and two fragments arising from cleavage of the recombinant protein at amino acid 215. The C-terminal fragment, containing the entire olfactomedin domain, was successfully isolated. When perfused into human and porcine eyes, this C-terminal fragment did not appreciably affect outflow facility.'] Does perfusion with the olfactomedin domain of myocilin affect outflow facility?