AGE VARIATIONS IN NUMBER AND STRUCTURE OF HUMAN GINGIVAL LANGERHANS CELLS

The Langerhans cell, a dendritic component of stratified epithelia, wh ich is an antigen presenter to other members of the immune chain, is a permanent resident of the oral mucosa that plays a role in local defe nse. To detect age-related changes, fragments of gingival epithelium s pontaneously accompanying dental removals were processed for electron microscopy (EM). Monoclonal antibodies DAKO CD1 or HLA-DR followed by biotinized immunoglobulin-streptoavidin peroxidase were used to identi fy the Langerhans cells with the light microscope. The healthy gum epi thelium in the young has a constant population of 29 +/- 5 Langerhans per light microscope field under the 10X objective. Ultrastructurally it reveals its specific bodies (Birbeck's). In all patients over 60 ye ars, light microscopy shows a drastic decrease of Langerhans cells. Th ese are rounded, with shorter cytoplasmic processes. The EM proves tha t these few remaining Langerhans have lost their specific Birbeck bodi es. Present observations indicate that these cells change markedly in number and structure. This fact is probably the expression of immunolo gic malfunction, at least locally.