Fig 1.
The histological sections of control, cEDS, hEDS, and hEDS-Scleroderma patients stained with H&E and PS.
(A). H&E-stained histological sections showing thick, organized collagen bundles for control skin and disordered, thin ones in the disrupted regions. The areas marked as *, **, and *** show the heterogeneous collagen density throughout the section for the sample obtained from hEDS, Scleroderma patient. (B). Histological sections from all four groups were stained with PS and imaged under polarized. Control samples showed red stains throughout the section, whereas cEDS and hEDS exhibited localized islets of yellow stained area. In the case of hEDS-Scleroderma, the yellow stain is widespread throughout the section. (C). Pie-chart distribution of the yellow/red stained areas ratio for each patient. Scale bars are 500μm.
Fig 2.
Correlated AFM and PS-stained images, identifying intact and compromised regions within the skin samples.
(A) showcases selected AFM images from areas of PS-stained samples referred to as red on the right and yellow on the left. All fibrils in the red-stain area of all four cases were structurally homogeneous with long, aligned, and unidirectional collagen fibrils. In contrast, yellow-stained, disrupted areas exhibited random orientation and structural disorganization in the collagen matrix. (B)presents Complementary AFM images from the disrupted area (yellow stained) from cEDS, hEDS, and hEDS-Scleroderma samples, highlighting the random orientation of the collagen fibrils along with wrinkled, swollen, and amorphous collagen matrix (highlighted with stars).
Fig 3.
Collagen fibrils’ Young’s moduli distributions of skin section’s healthy and disrupted area.
(A). Shows an unimodal distribution of Young modulus for control skin in healthy and disrupted regions. This peak shifts gradually to the smaller value, indicating weaker collagen when transiting from control samples to cEDS (indicated by a star). This shift is more pronounced when moving to hEDS and hEDS scleroderma samples. The red dotted line presents the healthy collagen distribution in the control group. (B). Summary table of the collagen Young’s moduli medians and their prevenances. At 0.05 level, all Younge modulus distributions between healthy and disrupted collagen are significant. Additionally, disrupted and healthy distribution within the same group is significant except for the control skin.
Table 1.
Summary table of key findings.