Fibrils, anchoring

Figure 3.10. Diagram illustrating the components of the dermis. Collagen type VII fibrils anchor the epidermis to the dermis. Collagen fibrils in dermis are composed of types I, III, and V and are coated with proteoglycans (PGs).

Grenz zone prominent, elastogenesis, elastosis, collagen degeneration, loss of anchoring fibrils... 

The columnar, cuboidal basal cells are 18-20 xm in height and 8-10 iim in diameter. They form a monolayer adhered to a basement membrane by hemidesmosomes which are linked to anchoring fibrils of collagen type VII. At the lateral borders, basal cells are extensively interdigitated and joined together in places only by junctional complexes (zonula adherens), desmosomes, and gap junctions. 

Beaded filament and anchoring fibril collagens (types VI and VII) 508... 

VIP 1 Basement membranes Long-chain, antiparallel dimers, anchoring fibrils ... 

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.

Collagen VII forms the anchoring fibrils in the reticular lamina that link the basement membrane to underlying connective tissue (Burgeson et al., 1985 Sakai et al., 1986). These attachment fibers are particularly abundant along the epidermal-dermal basement membrane, in the amnion, in lung, and in other sites where basement membranes are under tension. The fibers of collagen VII form a centrosymmetrically banded structure... 

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