Figure 6.

Proteomics based protein–protein interaction networks identify BAMBI as a potential master regulator of the collagen interactome in pCAVS. (A) Protein–Protein Interaction network showing relationship BAMBI (Supplemental Figure S5) relative to the ECM proteome and key valvular development proteins (Supplemental Table S6). (B) Quantification of qRT-PCR expression data on BAMBI (normalized to GAPDH), between patient categories. One-way ANOVA shows significant differential expression between patient categories (*p-value 0.013), with significant reduction in pCAVS (MWU *p-value 0.045) and trending reduction in aCAVS (MWU p-value 0.053) compared to normal pediatric patients. (Normal n = 2; pCAVS n = 12; aCAVS n = 5) C. Quantification of qRT-PCR expression data on BAMBI (normalized to GAPDH) of CAVS patients, compared between pediatric age categories (Infant n = 2; Young Child n = 3; Child n = 2; Adolescent n = 5; Adult n = 6). A suggestive trending decrease of BAMBI expression as a function of pediatric age categories is seen (ANOVA p-value 0.096) (Table 1; Supplemental Table S7). (D) DAB stain area quantification of BAMBI IHC of select valves in the cohort. (E) Representative immunohistochemistry staining of BAMBI in a selection of pCAVS and normal valves 20× (top) and 40 × zoom are shown. BAMBI positive cells appear highly localized, shown in dotted lines. Verhoeff van Geison (VVG) staining on the same valve section post-IHC study is shown (middle). Movat’s Pentachrome staining of a serial valve section (bottom). Positive BAMBI staining in pCAVS corresponds heavily to areas low in collagen staining (VVG) and high in GAG staining (Movat’s), while normal valve shows positive staining in collagen and elastin rich regions.