New understanding that underlying ‘tight junction’ skin barrier in eczema may also be damaged

Recent thinking on eczema has concentrated on damage to the stratum corneum, the top layer of our skin. However, new research by Dr Lisa Beck and colleagues in the Department of Dermatology at the University of Rochester Medical Center suggests that second skin barrier structure, under the stratum corneum, consisting of cell-to-cell connections known as tight junctions, is also faulty in eczema patients and may play a role in the development of the disease. Tightening both leaky barriers may be a more effective treatment for eczema patients than the anti-inflammatory drugs and topical anti-inflammatory creams and ointments that currenlty offer limited relief and have negative side effects.

To better understand the role of tight junctions in eczema, Beck and her team studied skin samples from eczema patients and healthy individuals. Using resistance and permeability tests, they discovered that tight junctions, which act like a gate controlling the passage of water and particles, were strong and tight in healthy skin samples, yet loose and porous in the skin of eczema patients.

On further investigation, they found that a particular tight junction protein, claudin-1, which determines the strength and permeability of tight junctions in skin, is significantly reduced in the skin of eczema patients, but not in healthy individuals or individuals with psoriasis, another common chronic skin disease. They demonstrated that reducing claudin-1 expression in skin cells from healthy donors made the tight junctions leaky and more permeable, a finding in line with results of other research groups.

They suggest that reduced claudin-1 may increase reactivity to environmental allergens in people with eczema and that increasing claudin-1 to combat eczema could be a treatment approach worth exploring.

Barrier problems, and in particular tight junction defects, are recognised as a common feature in many other inflammatory diseases, such as inflammatory bowel disease and asthma, where the lining of the intestine and the airways is weakened, which is why Beck and her team decided to focus on the role of this barrier structure in eczema.

Journal of Allergy and Clinical Immunology

December 2010

Click here for more research on possible causes of eczema

For LINKS to freefrom skin care products click here.