Fig. 1: High level of versican-V1 in MS lesions is associated with low number of BCAS1⁺ cells.

a, b Immunofluorescent images comparing control human brain tissue (no documented neurological condition) and MS brain lesions from 3 cases (MS163, 230, 352) labeled with DAPI for cell nuclei (blue), CD45 for immune cells (green) and versican-V1 (red). Active lesion areas were tracked by prominent accumulation of CD45⁺ cells. Images were acquired with slide scanner a and laser confocal microscopy (b, z-stack). Yellow boxes indicate lesions and dotted white lines specify the areas shown at higher magnification in b. c, d Brain tissue samples from 6 people with MS described in Supplemental Table 1 were immunohistochemically stained for versican-V1 and BCAS1. Representative images from two different patients (15-06 and 14-038) are shown. White matter lesion (WML) areas were tracked by loss of luxol fast blue (LFB) staining. Yellow rings indicate the analyzed sites within the lesions and blue squares in each of the left panels (lower magnification) specify the areas shown at higher magnification to the right. Staining was repeated twice and showed the same results. e Bar graph comparing the number of BCAS1⁺ cells in 19 regions of interest (ROI) with high or low level of versican-V1 deposition, n = 19 ROIs from 9 lesions acquired from six individual MS brain samples. Data are represented as mean ± SEM.  Two-tailed Mann–Whitney U-test; significance indicated as **p  = 0.0029. Source data are in the source data file.