Figure 4. T-cell infiltrates are reduced 3 months after HSP70i_Q435A treatment.

T-cell infiltrates were evaluated in perilesional tissue sections. (a) Sample stainings for CD3 alone and for CD3 and CD8 are shown at different time points, the latter performed to establish CD4:CD8 ratios. Single stained cells are counted as CD4⁺. Scale bar = 100 μm. (b) In violet, quantification of total T-cell infiltrates over time in repigmenting skin biopsies (n = 4) expressed per epidermal length, with densities initially trending toward an increase followed by a significant decrease by week 15. In orange, CD4:CD8 ratios (n = 4) follow the same trend as CD8 T cells alone. (c) A significant decrease in T cells is found during repigmentation of DNA-treated lesions, whereas a significant increase in the CD4/CD8 ratio at week 7 suggests that fluctuations follow the CD4 subset rather than cytotoxic T cells. (d) By contrast, the number of infiltrating T cells in vehicle-treated skin (n = 3) does not vary from the pretreatment numbers also observed in DNA-treated lesions. HSP70i_Q435A, inducible HSP70_Q435A.