In vitro exposure of murine macrophages to ultraviolet light induces apoptosis

Ultraviolet light is a known exogenous stimuli with the ability to activate cell death by apoptosis. This study was done to examine the biologic effects of different energy levels of short wavelength UV light on cultured mouse macrophages. Cell proliferation, DNA content, and cellular ultrastructural architecture analysis demonstrated that ultraviolet light induces apoptosis in murine macrophages in culture. Exposure to 0.12J/cm2 evokes progressive cell demise with the classical features associated with apoptosis, whereas exposure to 5.0 J/cm2 results in extensive DNA degradation and crosslinking of cellular proteins. These two phenotypes are qualitatively described.