Identification and analysis of γH2AX foci in mouse jejunum touch-prints (A, B, C), mouse tongue sections (D, E, F) and human blood lymphocytes. (G, H, I). Images were acquired by confocal laser scanning microscopy from non-irradiated specimens (A, D, G), irradiated with γ-rays at 3 Gy (B, E), 0.6 Gy (H), 5 Gy (C, F) and 1.5 Gy (I). The red channel corresponds to PI staining; the green channel corresponds to γH2AX staining. Examples of nuclei identification and focus automatic identification and counting by our program are shown on inserts in the top left corner of panels C, F and I.