Table 1.

Cultured keratinocytes from lupus patients show significant increases in cytotoxicity following UVR treatment

The irradiated cells were incubated in a humidified incubator for 24 h at 37°C in a 5% CO₂ atmosphere, and cell viability was then determined by the acridine orange/ethidium bromide (AO/EB) test.†Each cell strain from each donor was tested at least three times, and the values were summed and expressed as mean ± 1 s.d.Percent cytotoxicity = T_UVR − T, where T_UVR is the cytotoxicity in irradiated keratinocytes and T is cytotoxicity in sham-irradiated keratinocytes.*P < 0.001 (versus cells from adult controls), P < 0.001 (versus cells from neonatal foreskin); **P < 0.001 (versus cells from neonatal foreskin), P < 0.01 (versus cells from adult controls); ***P < 0.01 (versus cells from neonatal foreskin).