Arpe 19 human retinal pigment epithelial cell line

We used the ARPE-19 human retinal pigment epithelial cell line (American Type Culture Collection, Manassas, VA) as ocular cells, and the MT-2 cell line as an HTLV-1-infected T-cell line. We used Jurkat cells as a control T-cell line. MT2 and Jurkat cells were cultured in RPMI 1640 (Wako Pure Chemical Corporation, Osaka, Japan) supplemented with 10% fetal bovine serum (FBS) (GE Healthcare Japan, Tokyo, Japan) and 1% penicillin/streptomycin. ARPE-19 cells were cultured in minimum essential medium (Wako Pure Chemical Corporation) with the same supplements. All cell lines were incubated in a humidified incubator at 37°C under an atmosphere of 5% CO₂. In vitro infection by HTLV-1 was performed using the standard co-culture method (Akagi et al., 1986 (link); Graziano et al., 1987 (link); Liu et al., 2006 (link)). Briefly, ARPE-19 cells were plated and co-cultured with three times the number of MT2 or Jurkat cells at 48 h using cell culture inserts (Thermo Fisher Scientific, Waltham, MA). 1.5 × 10⁵ ARPE-19 cells were used in cytometric bead assay (CBA) and annexin V assay. 2 × 10⁴ ARPE-19 cells were used in cell counts, TNF receptor analysis, and the measurement of HTLV-1 proviral load.

As ocular cells, the adult retinal pigment epithelial cell line (ARPE)-19 human retinal pigment epithelial cell line (American Type Culture Collection, Manassas, VA), a spontaneously immortalized cell line, was cultured in Dulbecco’s modified Eagle’s medium (Wako Pure Chemical Corporation, Osaka, Japan) supplemented with 10% heat-inactivated fetal bovine serum (FBS; GE Healthcare Japan, Tokyo, Japan) and 1% penicillin and streptomycin (P/S) antibiotic solution. The MT2 cell line and TL-Om1 were used as HTLV-1-infected T-cell lines, and Jurkat cells were used as a control T-cell line. MT2, TL-Om1 and Jurkat cells were cultured in RPMI 1640 medium (Wako Pure Chemical Corporation) with the same supplements. All cell lines were incubated at 37°C, under 5% CO₂. Cell culture inserts with 0.4-μm pores (Greiner Bio-One, Kremsmünster, Austria) were used to prevent the contamination of ARPE cells by other cells.