The
proteoglycans (PGs) in pooled normal
scars and pooled
hypertrophic scars were extracted with 4 M
guanidinium chloride and isolated by
DEAE-cellulose chromatography. The PG samples were then fractionated further by dissociative
CsCl density gradient sedimentation. Following cleavage of the density gradient PG fractions with alkaline NaB3H4, the
glycosaminoglycan (GAG) constituents were isolated and analyzed by quantitative
cellulose acetate electrophoresis. In addition, single samples of normal skin and a
keloid scar were also analyzed. The results showed that the
hypertrophic scars had a higher average content of extractable and also residual PGs than did the normal
scars but a wide range of values was obtained for each type of
scar. Some differences were noted in the amounts and distribution of the GAGs in
CsCl gradient fractions, in the different types of
scar tissue. The PGs in tissues were distributed in low-, medium-, and high density fractions and are, therefore, heterogeneous.
Dermatan sulfate (DS) was the major GAG in each tissue and smaller quantities of
chondroitin sulfate (CS),
heparan sulfate (HS), and
heparin (HP) were also present. In addition, 2 other GAG constituents were also detected. Based on the susceptibility of these GAGs to
enzymes and
nitrous acid treatments, one was a HS or HP while the second was a DS. The major differences in the PG composition of the
scar tissues were the higher proportions of low-density CS-PGs in the
keloid scar and of low density DS-PGs in hypertrophic and
keloid scars.