RPE-J is a retinal pigment epithelial (RPE) cell line derived from primary cultures of RPE cells taken from 7-day-old Long-Evans rats.

The RPE-J clone was selected for an epithelioid morphology and for expression of circumferential staining with antibody against the tight junction protein 1, (Tjp1, ZO-1).

The cells express a transformed phenotype at the permissive temperature (33°C), and a non-transformed phenotype at the non-permissive temperature (40°C). They must be cultured at the permissive temperature and do not grow at 37°C.

When RPE-J cells are grown on nitrocellulose filters coated with a thin layer of Matrigel in the presence of 10(-8) M retinoic acid for 6 days at 33°C and then switched to the non-permissive temperature of 40°C for 33 to 36 hours, they acquire a differentiated polarized RPE phenotype. Under these conditions, RPE-J cells exhibit circumferential staining for the tight-junction protein ZO-1 and acquire a transepithelial resistance of 350 ohms/cm2.xa0RefNabi IR, et al. Immortalization of polarized rat retinal pigment epithelium. J. Cell Sci. 104: 37-49, 1993. PubMed: 8383696

RPE-J is the only established RPE cell line that maintains epithelial cell surface polarity. The cells retain many properties of RPE including expression of the rat RPE marker RET-PE2 and the ability to phagocytose latex beads.RefNabi IR, et al. Immortalization of polarized rat retinal pigment epithelium. J. Cell Sci. 104: 37-49, 1993. PubMed: 8383696

A culture submitted to the ATCC in July 1995 was found to be contaminated with Mycoplasma hyorhinis and was cured by a 21-day treatment with BM Cycline. The cells were assayed for mycoplasma by the Hoechst stain and the standard culture test over a six-week period following treatment and all tests were negative.

1. Remove and discard culture medium.
2. Briefly rinse the cell layer with 0.25% (w/v) Trypsin-0.53 mMxa0EDTA solution to remove all traces of serum that contains trypsin inhibitor.
3. Add 2.0 to 3.0 mL of Trypsin-EDTA solution to flask and observe cells under an inverted microscope until cell layer is dispersed (usually within 5 to 15 minutes).
   Note: To avoid clumping do not agitate the cells by hitting or shaking the flask while waiting for the cells to detach. Cells that are difficult to detach may be placed at 37°C to facilitate dispersal.
4. Add 6.0 to 8.0 mL of complete growth medium and aspirate cells by gently pipetting.
5. Transfer cell suspension to a centrifuge tube and spin at approximately 125 x g for 5 to 10 minutes. Discard supernatant.
6. Resuspend the cell pellet in fresh growth medium.xa0 Add appropriate aliquots of cell suspension to new culture vessels.
7. Place culture vessels in incubators at 33°C.

Nabi IR, et al. Immortalization of polarized rat retinal pigment epithelium. J. Cell Sci. 104: 37-49, 1993. PubMed: 8383696