Lamina propria

Lamina propria is a thin layer of connective tissue that forms part of the moist linings known as mucous membranes or mucosa, which line various tubes in the body, such as the respiratory tract, the gastrointestinal tract, and the urogenital tract.

Structure

The lamina propria is a component of the mucosa, so it is found in many organs, including the mouth, nose, eyelids, lungs, stomach, and intestines. It is a loose connective tissue, hence it is not as fibrous as the connective tissue of the skin. It contains blood vessels and lymphatic vessels to support the epithelium, as well as fibroblasts, macrophages, and mast cells.

Function

The lamina propria contains the immune cells of the mucosa, and is the site of immune responses in the mucosa. It provides support and nutrition to the epithelium, as well as the means to bind to the underlying tissue. The fibroblasts produce the collagen of the lamina propria.

Clinical significance

Changes in the lamina propria can indicate various diseases. For example, an increase in the number of immune cells can indicate an infection or inflammation. In celiac disease, there is a characteristic hyperplasia of the lamina propria.

See also

• Mucous membrane
• Connective tissue
• Epithelium

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  Oral mucosa