Mouse skin: neutron irradiation

The objective of this investigation was to characterize, at individual level, the transcriptional response and the onset of regenerative processes in mouse skin irradiated with different doses of fast neutrons. We performed a high-throughput gene expression analysis, by DNA oligonucleotide microarray on 24 three months old C57Bl/6 mice irradiated with 0, 0,2 and 1 Gy of mono-energetic 14 MeV neutron. The results, partially validated by quantitative real time RT-PCR, showed an up-regulation of a sub-class of keratin and keratin associated proteins, and of components of the S100 family of Ca2+-binding proteins which was limited to the lower dose. We conclude that the dose-dependent differential gene expression, reminiscent of the onset of re-epithelialization and wound healing, depends upon the proportion of cells carrying multiple lesions at chromosomal level post-irradiation, and it represents an in vivo evidence of a skin regenerative program exerted independently from DNA repair-associated pathways. Four condition experiment: 6h and 24h from 0.2 Gy neutron irradiation; 6h and 24 from 1 Gy neutron irradiation. One replicate for each condition