Lamellar bodies
In
type II alveolar cells in the lungs, and in keratinocytes in the skin. They are oblong structures, appearing about 300-400 nm in width and 100-150 nm in length in transmission electron microscopy images. Lamellar bodies in the alveoli of the lungs fuse with the cell membrane and release pulmonary surfactant into the extracellular space.[1][2]
Role in lungs
In
phospholipids) that are stored in the lamellar bodies serve as pulmonary surfactant after being released from the cell. In 1964, using transmission electron microscopy, which at that time was a relatively new tool for ultrastructural elucidation, John Balis identified the presence of lamellar bodies in type II alveolar cells, and further noted that upon their exocytotic migration to the alveolar surface, lamellar contents would uniformly unravel and spread along the circumference of the alveolus, thus lowering surface tension and similarly, the required alveolar inflation force.[3]
Role in epidermis
In the upper
substrates or inhibitors prior to secretion.[5]
Recent work suggests that lamellar bodies form a continuous membranous structure with the
trans-Golgi network
.
Lamellar body secretion and lipid structure is abnormal in the epidermis of patients with
pruritus
(itch).
Deficient lipid membrane causes cold damage in patients of asteatotic eczema (also known as winter eczema).