"This may be an important finding for premature infants, who often lack a competent skin barrier," said Mary Williams, MD, UCSF adjunct professor of dermatology and pediatrics. "An immature skin barrier can contribute to the illness and death of these premature infants."
Williams and her UCSF research colleagues presented their findings on fetal skin development today (May 4) at the 1998 Pediatric Academic Societies' annual meeting.
Mammals normally have a competent skin barrier -- skin that can prevent excessive water loss from the inside of the body to the outside air -- at birth. This barrier is formed by the outermost layers of the skin, the multilayered stratum corneum (SC), which consists of dead cells surrounded by sheets of fat. The SC is made by the epidermis, a layer of skin just beneath the SC that is made up of living cells.
But babies born under 32 weeks of gestation lack this barrier and have been shown to have a very thin SC, said Williams. "Without this barrier these infants are susceptible to hypothermia, water loss, electrolyte imbalance, and infection," she said.
Previous studies on fetal rat skin cells by UCSF researchers have shown that formation of a competent barrier is accompanied by formation of a multilayered SC. Certain hormones, such as thyroid hormone and estrogens have also been shown to accelerate barrier maturation. However, past research has shown these hormones are not required for barrier formation.
Williams and research colleagues have previously shown that certain
activators, molecules that bind to the surface or receptors of hormones,
accelerate barrier formation
Contact: Lordelyn P. del Rosario
University of California - San Francisco