Fig. 2

Three stages of γH2AX reactivity in cases. In stage 1, DNA damage is evident in the ependyma but not in the grey or white matter. In stage 2, DNA damage is evident in the ependymal and subependymal cells, as well as sub-pial astrocytes (not shown) and peri-neuronal glial cells in the grey matter. In stage 3 DNA damage is evident in the ependymal and subependymal cells, peri-neuronal glial cells in the grey matter, and oligodendrocytes in the white matter. Healthy, normal controls do not have any evidence of γH2AX reactivity in the ependymal, grey matter, or white matter. Stage 1 had a mean positive cell density score of 37% in ependymal cells (SE = 7.3), and 0% in astrocytes and oligodendrocytes. Stage 2 had a mean positive cell density score of 59% (SE = 19.4) in ependymal cells, 11% (SE = 5.7) in astrocytes, and 0% in oligodendrocytes. Stage 3 had a mean positive cell density score of 96% (SE = 2.7) in ependymal cells, 44% (SE = 10.9) in astrocytes, and 28% (SE = 10.2) in oligodendrocytes. Using the Kruskal-Wallis one way analysis of variance, statistically significant (p < 0.001) differences were observed between stages 1, 2 and 3 in the positive cell density scores in ependymal cells, astrocytes, and oligodendrocytes, marked with asterisks (*)