Type VII collagen

Another 3-D cornea model, comprising rabbit primary cultures of epithelial and stromal cells as well as mouse immortalized endothelial cells, was described in 1994 by Zieske and coworkers [70], They showed the influence of endothelial cells on the formation of a tightly packed, multilayered epithelium as well as the expression of laminin, type VII collagen, a6 integrin, keratin K3, and a-enolase. Furthermore, their findings suggested that the formation of an in vivo-like epithelium requires the cultivation of the 3-D corneal construct under AIC conditions. By contrast, LCC methods of cultivating corneal equivalents in the absence of endothelial cells failed to promote the expression of differentiation markers and basement membrane components. 

The NCI domain of type VII collagen binds to the /33 chain of laminin, " laminin-5 a3(33 2), and type IV collagen. The triple helical domain of type VII collagen functions to promote the migration of human keratinocytes. °... 

Type VII collagen is composed of three identical a chains, each consisting of a 145 kDa central collagenous triple helical segment, flanked by a large 145 kDa N-terminal NC domain (NCI) and a smaller 34 kDa... 

R. E. Burgeson, Type VII Collagen. In Structure and Function of Collagen Types R. Mayne, R. E. Burgeson, Eds. Academic Press Orlando, FL, 1987 pp 145-172. 

Vindevoghel, L., Kon, A., Lechleider, R.J., Uitto, J., Roberts, A.B., and Mauviel, A. 1998a. Smad-dependent transcriptional activation of human type VII collagen gene (COL7A1) promoter by transforming growth factor-beta. J. Biol. Chem. 273 13053-13057. 

Fig. 1. (A) Scanning electron micrograph of human skin. The epidermis has pulled away from part of the basement membrane. (B and C) Transmission electron micrograph through the epidermal-dermal junction of human skin. Keratinocytes (KF) are the cells in the human epidermis. LD, The lamina densa of the basement membrane LL, the lamina lucida. Typical anchoring fibrils (AF) formed from type VII collagen are shown at higher power in C. Courtesy of Dr. K. Holbrook, University of Washington.

The reticular layer of basement membrane in a tissue such as the skin contains a variety of matrix structures. Strands of basement membrane may project down to type I collagen fibers. Anchoring fibers, banded fibers composed of type VII collagen, extend into the basement mem-... 

Type IV collagen in the basement membrane Type VII collagen... 

Linear IgA disease is an acquired subepidermal bullous disease characterized by linear deposits of IgA at the cutaneous basement membrane zone and by circulating IgA anti-basement membrane antibodies. Although the cause of linear IgA disease is usually unknown, a few cases have been reported to follow ingestion of drugs, especially vancomycin and diclofenac. A patient with penicillin G-induced linear IgA disease who had circulating IgA antibodies showed specificity against type VII collagen (146). 

Delbaldo C, Chen M, Friedli A, Prins C, Desmeules J, 86. Saurat JH, Woodley DT, Borradori L. Drug-induced epidermolysis bullosa acquisita with antibodies to type VII collagen. J Am Acad Dermatol 2002 46(Suppl 5) SI6I-4. 

Type VII collagen is a non-fibrous, anchoring fibril that binds large type I collagen fibers in the stroma to the lamina densa section of the basal lamina. Type VII procollagen... 

Fig. 5.3 Dimeric structure of collagen type VII anchoring fibrils, (a) Type VII collagen triple helix. The non-collagenous (NC)...

Keene DR, Sakai LY, Lunstrum GP et al. (1987). Type VII collagen forms an extended network of anchoring fibrils. J Cell Biol, 104, 611-621. 

Leigh IM, Purkis PE and Bruckner-Tuderman L (1987). LH-7.2 monoclonal antibody detects type-VII collagen in the sublamina densa zone of ecto-dermally derived epithelia, including skin. Epithe-lia, 1, 17-29. 

Rusenko, K.W., Gammon, W.R., Fine, J.D., and Briggaman, R.A. (1989). The carboxyl-terminal domain of type VII collagen is present at the basement membrane in recessive dystrophic epidermolysis bullosa, J. Invest. Dermatol, 92 623-627. 

---