Bovine lactoferrin stimulates human corneal epithelial alkali wound healing in vitro.
OBJECTIVE
The purpose of this study was to investigate the effect of bovine lactoferrin (BLF) on human corneal epithelial wound healing using an in vitro alkali-induced wound model and to understand its role in promoting wound healing.


METHODS
Confluent human corneal limbal epithelial (HCLE) cells wounded using 0.5 microL of 0.1 M sodium hydroxide were treated with BLF (0, 0.1, 1, 2.5, and 5 mg/mL) or anti-human interleukin-6 (IL-6) receptor neutralizing antibody (anti-IL-6 antibody; 1, 10, and 50 microg/mL) or tyrphostin AG1295 (an inhibitor of platelet-derived growth factor [PDGF] receptor kinase; 1 and 10 microM), IL-6, or PDGF-BB. The conditioned medium collected for BLF treatment (0 and 5 mg/mL) was analyzed using a protein array for a number of cytokines/growth factors involved in corneal wound healing. A preliminary animal study using mice was carried out to determine the effect of BLF on alkali wounds.


RESULTS
BLF at 2.5 and 5 mg/mL promoted wound healing (P<0.01). During wound closure, BLF upregulated PDGF-BB 180-fold and IL-6 10-fold compared with control. Treatment with tyrphostin AG1295 (10 microM; P<0.01) or anti-IL-6 antibody (50 microg/mL; P<0.01) in the presence of BLF inhibited wound closure, whereas the addition of exogenous IL-6 and PDGF-BB promoted wound closure. Preliminary animal studies have shown that BLF (5 mg/mL) promotes alkali wound healing in vivo.


CONCLUSIONS
These results suggest that BLF at >or=2.5 mg/mL stimulates HCLE wound healing, and this stimulation is mediated through the upregulation of PDGF or IL-6.
Pattamatta
Ushasree
U
Institute for Eye Research, Sydney, New South Wales, Australia.
Willcox
Mark
M
Stapleton
Fiona
F
Cole
Nerida
N
Garrett
Qian
Q
D000818:Animals; D002057:Burns, Chemical / Q000188:drug therapy* / Q000473:pathology; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D019573:Epithelium, Corneal / Q000187:drug effects* / Q000473:pathology; D005126:Eye Burns / Q000139:chemically induced* / Q000473:pathology; D005353:Fibronectins / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007781:Lactoferrin / Q000187:drug effects*; D016850:Limbus Corneae / Q000166:cytology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012972:Sodium Hydroxide / Q000633:toxicity; D020032:Tyrphostins / Q000494:pharmacology; D014945:Wound Healing / Q000187:drug effects*
C407689:6,7-dimethoxy-2-phenylquinoxaline; D016207:Cytokines; D005353:Fibronectins; D020032:Tyrphostins; D012972:Sodium Hydroxide; D007781:Lactoferrin