Figure 5

CXCR4 positive inflammatory cells infiltrate diabetic DRG. Large influx of CXCR4-eGFP positive cells into HFD diabetic mice DRG (A and B, asterisk). In contrast virtually no cells were observed in non-diabetic RD DRG (C and D). Quantification: 79.131 ± 15.03 CXCR4 expressing inflammatory cells infiltrating into HFD DRG compared to 1.363 ± 0.82 in RD DRG. Characterization of the nature of the inflammatory infiltrate revealed the presence of CD3 positive T-cells in diabetic DRG (E-G, arrows). On the contrary virtually no CD3 positive T-cells were noted in non-diabetic DRG (F). Quantification: 39.132 ± 11.14 CD3 positive cells in HFD DRG compared to 1.945 ± 0.84 in RD DRG. Interestingly, cells infiltrating the diabetic DRG at the dorsal root entry (arrows) were CD68 positive macrophages (I-K). Virtually no CD68 positive cells were noted in non-diabetic DRG (L). Quantification: 16.333 ± 3.15 CD68 positive cells in HFD DRG compared to 0.205 ± 0.41 in RD DRG. The number of F4/80 positive macrophages in diabetic DRG (M and N) was the same compared to non-diabetic DRG (O and P). Quantification: 26.615 ± 2.48 F4/80 positive cells in HFD DRG compared to 26.558 ± 2.72 cells in RD DRG. However, F4/80 positive macrophages exhibited an altered morphology in diabetic DRG (N, arrows) compared with non-diabetic DRG (P, arrows). Indeed, F4/80 positive cells in diabetic DRG assumed the morphology of activated macrophages (N, arrows). No B220 positive B-cells were noted in diabetic DRG (Q-S) using an antibody against B220 able to visualize B-cells in the spleen (T). (Magnification 10X, scale bar 500 μm: E, I, Q; 20x, scale bar 250 μm: A-D, F, J, M, O, R; 40X scale bar 50 μm: G, H, K, L, N, P, S, T). r: dorsal root. Values expressed as means ± SD (p <0.001).