Reticular connective tissue is a type of tissue found in the body that is supported with a branching framework of collagen fibers known as reticular fibers. These fibers are present in many types of connective tissue and are particularly heavily concentrated in this tissue. Some examples of structures in the body that include this type of connective tissue include the liver, spleen, and lymph nodes. Staining and magnification with microscopy is needed to identify this tissue type.
In reticular connective tissue, cells that secrete type III collagen work together to create a stable lattice of fibers. The fibers provide support and stability to other types of cells. While the lattice itself is fixed in place through the connections between the fibers and the cells, other types of cells along with fluids can move freely across and through the lattice. This allows for free exchanges between cells, while still providing a reinforcing framework that will support an organ or lymph node.
Viewed up close, the reticular fibers can be seen in the form of a series of branching threads. The tissue is similar to connective tissue with a high amount of elastic fibers, except that in reticular connective tissue, the collagen fibers are branched, while elastic fibers lie parallel to each other. The structure of the collagen lattice provides more strength and support to the underlying tissue and is less springy than elastic tissue.
Like other types of tissue in the body, the reticular connection tissue is constantly broken down, recycled, and replaced with new tissue. Cells within the lattice will break down when they are no longer able to function and new collagen strands are constantly being generated to replace strands that have broken up. Specialized cells are involved in the formation of new reticular fibers and the maintenance of existing fibers that are already part of the collagen lattice in the reticular connective tissue.
Depending on the level of magnification, different aspects of reticular tissue can be visible. Low magnification will reveal boundaries between this tissue type and others, showing where the dense framework leaves off and other types of tissue begin. More close magnification will show the individual fibers and the cells and fluids that are interspersed along the lattice. Microscopic examination of biopsy samples will include reviews at different levels of magnification for physical changes and other signs of disease or injury. Biopsies can reveal abnormal cell growth or breakdown along with other signs of injury.