However, within the AACG group, although the TGFβ2 levels in AH did not differ significantly from the control level when all AACG patients were grouped together, there were differences when the AACG patients were divided into high and normal intraocular pressure (IOP); TGFβ2 of AACG patients with high IOP (> 21 mmHg) was significantly higher than those with normal IOP.
These results are consistent with the hypothesis that, in POAG, elevated expression of Gremlin by TM cells inhibits BMP-4 antagonism of TGF-beta2 and leads to increased ECM deposition and elevated IOP.