Collagen reorganization in leech wound healing.
BACKGROUND
Leeches respond to surgical lesions with the same sequence of events as that described for wound healing in vertebrates, where collagen is important for the development of tensions in healing wounds, functioning as an extracellular scaffold for accurate regeneration of the structures disrupted by surgical or traumatic actions.


RESULTS
In surgically lesioned leeches, newly synthesized collagen is arranged in hierarchical structures. Fibrils can be packed and shaped to form cords or tubular structures, thus acting as an extracellular scaffold that directs and organizes the outgrowth of new vessels and the migration of immune cells towards lesioned tissues. In these animals, the general architecture of collagen fibrils, generated during tissue regeneration, shows similarities to both the structural pattern of collagen bundles and assembly processes observed in several vertebrate systems (fish scales, amphibian skin and human cornea).


CONCLUSIONS
The production of extracellular matrix during wound healing in leeches is a surprising example of conservation of an extremely close relationship between the structure and function of molecular structures. It could be hypothesized that collagen structures, characterized not only by a striking structural complexity, but also by multifunctional purposes, are anatomical systems highly conserved throughout evolution.
Tettamanti
Gianluca
G
Department of Structural and Functional Biology, University of Insubria, Via J.H. Dunant 3, 21100 Varese, Italy.
Grimaldi
Annalisa
A
Congiu
Terenzio
T
Perletti
Gianpaolo
G
Raspanti
Mario
M
Valvassori
Roberto
R
de Eguileor
Magda
M
D000818:Animals; D003094:Collagen / Q000096:biosynthesis / Q000648:ultrastructure; D005109:Extracellular Matrix / Q000502:physiology; D047709:Hirudo medicinalis / Q000502:physiology*; D007150:Immunohistochemistry; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D023421:Models, Animal; D011509:Proteoglycans / Q000032:analysis; D014945:Wound Healing
D011509:Proteoglycans; D003094:Collagen