Pretreatment of human keratinocyte sheets with laminin 5 improves their grafting efficiency.
Laminin 5 is essential in epithelial attachment to stromal tissues, suggesting that it might improve keratinocyte attachment in a variety of clinical situations. In this study, we examined the effect of exogenous laminin 5 upon the efficiency of transplantation of keratinocyte sheets in animal models. Keratinocyte sheets were prepared according to the method of Rheinwald & Green (1975). Purified laminin 5 was added to the sheets of group 1 (1.0 microg per cm2), Dulbecco's modified Eagle's medium alone was added to group 2. The sheets were grafted to the panniculus carnosus of nude mice (BALB/C nu/nu) (n = 12) and nude rats (Fisher 344) (n = 15). The take rate was assessed by measurement of the area of surviving epithelium at 7 d postgrafting. Laminin 5 bound the keratinocyte sheets of group 1. At 7 d postgrafting, the area of epithelialization of group 1 was significantly larger than that of group 2. Immunohistochemistry staining showed that collagen IV, laminin 5, and collagen VII stained more strongly at the dermal-epidermal junction in group 1 than in group 2. Integrin chains alpha6 and beta4 were similar in both groups. Electron microscopy at day 3 after grafting, showed the lamina densa of group 1 to be more continuous than in group 2. Pretreatment of cultured human keratinocyte sheets with laminin 5 improved the extent of epithelial coverage and increased the rate of neobasement membrane formation. The results suggest that laminin 5 promotes epithelial attachment by increasing the rate of basement membrane assembly.
Plastic and Reconstructive Surgery, Kitasato University School of Medicine, Wound Healing Center, Kitasato University of Hospital, Sagihara, Japan.
A
A
Takeda
K
K
Kadoya
N
N
Shioya
E
E
Uchinuma
M
M
Tsunenaga
S
S
Amano
T
T
Nishiyama
R E
RE
Burgeson
D000818:Animals; D001485:Basement Membrane / Q000187:drug effects / Q000648:ultrastructure; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000494:pharmacology*; D017690:Cell Transplantation; D003094:Collagen / Q000032:analysis; D006085:Graft Survival / Q000187:drug effects*; D006801:Humans; D007150:Immunohistochemistry; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects / Q000637:transplantation*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D051381:Rats; D011916:Rats, Inbred F344; D011923:Rats, Nude; D012867:Skin / Q000737:chemistry / Q000187:drug effects / Q000648:ultrastructure; D016038:Skin Transplantation / Q000379:methods; D013997:Time Factors; D014183:Transplantation, Heterologous; D000097794:Kalinin
D015815:Cell Adhesion Molecules; D003094:Collagen; D000097794:Kalinin