As the human skin is composing of the epidermis, dermis, and hypodermis. As the largest organ of the human body our skin is astounding. It protects us from infection, endures radiation, senses temperature; and is flexible enough to withstand our everyday activities. An full thickness skin grafts exhibit less contracture during the postoperative healing process than split thickness skin grafts.
Since the 1960s, researchers have debated whether skin collagen was arranged randomly or had some kind of ordered orientation information vital to understand its pliability for further clinical use. Due to the skin’s pliable nature, researchers inferred that collagen and elastic fibers have some sort of geometric orientation like a rhomboidal net.
However, studies failed to demonstrate any organization; which is attributed to the tightly packed nature and complex intertwining of collagen fibers. Because the fibers are so tightly packing; it was impossible to determine if their orientation is ordering or random. So, we developing a way to essentially stretch a skin sample on a 2D plane; that increases the inter fiber space of the collagen but retains its core structure.
Human reticular dermis
Using multiphoton microscopy, a technique used to observe living tissue in fine detail; the team finding clear evidence that the collagen fibers were arranging in a mesh-like lattice; and not in the clear geometric orientation as previously hypothesizing. They even finding that the connective tissue know as elastic fibers were also distributing in the same way; something that was previously unobserving.
There was little information on how elastic fibers and collagen fibers in the skin related to each other. However, it was believing that the recoiling force of elastic fibers leading to the contraction of collagen; Understanding the geometric organization of fibers in the skin can lead to better insight into the mechanisms underlying human skin pliability that can be applied for future medical use in skin grafts and transplantation.
Fibrous micro architecture
The team intends to further their research by uncovering the relationship between the collagen network and elastic tissues, and hopes their new technique will be utilizing to study the fibrous microarchitecture in other connective tissue networks. Understanding the geometric organization of fibers in the reticular dermis improves the understanding of mechanisms underlying the pliability of human skin.
A high degree of local similarities in the direction of collagen and elastic fibers was observing. More than 80% of fibers had directional differences of ≤15°, regardless of layer. Combined multiphoton imaging and biaxial extension provides a research tool for studying the fibrous microarchitecture of the skin.