Langerhans cells are dendritic cells present in the epidermis with antigen-presenting capacities. We performed a quantitative analysis of Langerhans cell density in the anterior median chest skin of 286 autopsy cases (aged 0-88 yr). Langerhans cells were identified by an immuno-peroxidase technique for the visualization of S-100 protein and their densities were expressed as Langerhans cell number per epidermal surface area (cells/mm2).
As results of this study, 1) Langerhans cell densities reached their peak in the age of 10s to 30s, and were age-related declined in the density; 302.2±45.4 (mean±SE) versus 130.1±17.5/mm2 (respectively aged 20s versus 80s). 2) Morphologically dendritic processes of Langerhans cells were reduced with age after 60s, accompanied by the age-related thining of the epidermis.
The above findings suggest that immunological surveillance may be impaired in the aged-skin. These age-related changes may contribute to the increased susceptibility to cutaneous infection and development of skin cancer in elderly individuals.