Salivary EGF regulates eosinophil-derived TGF-alpha expression in hamster oral wounds.
Using hamster as an oral wound healing model, we examined eosinophils and their expression of transforming growth factor-alpha (TGF-alpha) and transforming growth factor-beta 1 (TGF-beta 1). Oral wounds healed approximately two times faster than their cutaneous counterparts. Eosinophils infiltrated prominently into oral wounds; however, unlike the dual expression of TGF-alpha and TGF-beta 1 in skin wounds, oral wound-associated eosinophils expressed TGF-beta 1, but not TGF-alpha. Because saliva is present in oral environments and contains epidermal growth factor (EGF) and TGF-alpha, sialoadenectomy was performed in this model to determine whether the lack of TGF-alpha expression by eosinophils in oral wounds is due to the presence of salivary EGF and/or TGF-alpha. We found that eosinophils in sialoadenectomized hamsters did express TGF-alpha during oral wound healing but that such expression was suppressed when EGF was added to their drinking water. Taken together, our findings suggest that eosinophil-derived TGF-alpha and salivary TGF-alpha/ EGF may have complementary roles in contributing to TGF-alpha in oral wound healing.
Yang
J
J
Department of Oral Medicine and Diagnostic Sciences, Harvard School of Dental Medicine, Boston, Massachusetts 02215, USA.
Tyler
L W
LW
Donoff
R B
RB
Song
B
B
Torio
A J
AJ
Gallagher
G T
GT
Tsuji
T
T
Elovic
A
A
McBride
J
J
Yung
C M
CM
Galli
S J
SJ
Weller
P F
PF
Wong
D T
DT
D000818:Animals; D006224:Cricetinae; D004804:Eosinophils / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000502:physiology*; D008297:Male; D009061:Mouth Mucosa / Q000293:injuries*; D012333:RNA, Messenger / Q000378:metabolism; D012463:Saliva / Q000378:metabolism*; D012469:Salivary Glands / Q000502:physiology; D013997:Time Factors; D016211:Transforming Growth Factor alpha / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing; D014950:Wounds, Penetrating / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology
D012333:RNA, Messenger; D016211:Transforming Growth Factor alpha; D004815:Epidermal Growth Factor