Modelling the infundibulum in acne

The human sebaceous-pilosebaceous infundibulum was isolated and maintained for 7 days. Infundibular viability was maintained over 7 days in this medium. The addition of 1 ng/ml interleukin 1 alpha (IL-1 alpha) caused hypercornification of the infundibulum similar to that seen in comedones which could be blocked by 1,000 ng/ml IL-1 receptor antagonist. However, in contrast to interferon gamma 1, IL-1 alpha had no effect on the expression of intercellular adhesion molecule or human leucocyte antigen type DR in infundibular keratinocytes. The addition of 5 ng/ml epidermal growth factor or 5 ng/ml transforming growth factor alpha to the medium caused a disorganization of the keratinocytes of the infundibulum. We are now, therefore, able to model histologically the major infundibular changes in acne. Furthermore, we suggest that IL-1 alpha causes the scaling seen in many inflammatory skin diseases.