Rj. Green et al., IMMUNOLOCALIZATION OF PLATELET-DERIVED GROWTH-FACTOR A-CHAIN AND B-CHAIN AND PDGF-ALPHA AND BETA-RECEPTORS IN HUMAN GINGIVAL WOUNDS, Journal of Periodontal Research, 32(2), 1997, pp. 209-214
Platelet-derived growth factor (PDGF) is a polypeptide growth factor w
hich has been implicated as a major mitogen involved in wound healing.
The PDGF appears to promote periodontal regeneration; however, its di
stribution in gingival tissues is not known and how it participates in
gingival wound healing is unclear. Using highly specific antibodies w
e have studied the distribution of PDGF A and B chains and alpha- and
beta-PDGF receptors in healing human gingival wounds. Wounds were crea
ted by making a 0.75 mm deep incision in the papilla of healthy human
gingiva and biopsies were obtained from the same site after 8 h and 1,
3, 7, 14 and 21 d. Frozen sections were immunostained with affinity p
urified antibodies. The results showed that both epithelium and fibrin
clot manifested positive immunostaining for anti-PDGF-A and B-chain a
ntibodies. Staining was present in unwounded and wounded epithelia, an
d in the fibrin clot it appeared to be more intense for the PDGF-A cha
in. Blood vessels in connective tissue were also positive while other
areas were largely negative. No significant staining was detectable in
healthy tissues for anti-PDGF-alpha or -beta receptor antibodies. How
ever, the wound site began to manifest positive immunostaining for ant
i beta-receptor antibody after 3 d of healing, became maximal at 7 d,
and then decreased. Our data indicate, but do not prove, that gingival
epithelium may be a source of PDGF A and B chains and that the A chai
n may have a more prominent role to play during early stages of healin
g. Expression of PDGF beta-receptor appears later at the wound site, i
ndicating that the PDGF B isomer may regulate later wound healing even
ts.