Construction of a Secondary Enclosure for UVB Irradiation of Mice

Abstract

UV irradiation is commonly used in murine models of skin cancers. Despite the popularity of using UVB rays to model photocarcinogenesis in animals, there is a lack of standardization in the secondary enclosures used to administer radiation. An appraisal of the literature also shows a general lack of details regarding the materials and procedures utilized in the fabrication of such enclosures. We present in this study a detailed overview of the construction of a UVB exposure chamber that successfully induces lesions in hairless mice. A standardized protocol for producing a UVB enclosure may reduce methodological variation in future studies seeking to investigate photocarcinogenesis in animals.

Figure 2

Inconsistencies in power output along the length of the UVB bulb. The floorplan of the box with representative power outputs noted under each cage position is shown, showing diminished power output localized to the position under the lamp corresponding to cage 1.

Figure 3

The UVB enclosure and lighting system induce lesion formation in SKH-1 mice. (a) Kaplan‒Meier analysis of tumor-free mice showing that lesions appeared after approximately 13 weeks of UVB irradiation, and all mice developed lesions by week 16, with no significant difference between genders. (b) Representative images of mice before lesion formation and after 17 weeks of UVB exposure.

Figure 1

Secondary UVB exposure chamber. Blueprint schematic of the enclosure from the (a) exterior side view, (b) exterior frontal view, (c) interior side view, and (d) three quarter aerial view. (e) Representative images of the enclosure. Illustrations were by Caroline Choi.