P58(IPK) inhibition of endoplasmic reticulum stress in human retinal capillary endothelial cells in vitro.

Purpose: The goal of this research was to determine if P58(IPK), a member of the Hsp40 family that inhibits eukaryotic initiation factor 2alpha (eIF2alpha), inhibits endoplasmic reticulum (ER) stress and leads to downregulated expression of vascular endothelial growth factor (VEGF) and decreased apoptosis in human retinal capillary endothelial cells (HRCECs).

Methods: Recombinant vectors were constructed using P58 in adeno-associated virus type 2 (rAAV2-P58 (IPK)) and P58 RNA in the plasmid pGIPZ (pGIPZ-P58(IPK)). The four experimental groups were: (1) non-transfected/non ER stressed control; (2) non-transfected/ER stressed; (3) rAAV2-P58(IPK)-transfected/ER stressed; and (4) pGIPZ- P58(IPK) RNAi transfected/ER stressed.