1993 年 39 巻 2 号 p. 151-157
The immune response plays an important role not only in defense against various infections from the external environment, but also in the homeostasis of the internal environment. However, advancing age is accompanied by declining immunocompentency.
Langerhans cells are known to be antigen presenting cells residing in the epithelium of human oral mucosa. Age-related changes in the numbers of CD1a and HLA-DR positive Langerhans cells were investigated in normal human gingival mucosa using an immunohistochemical technique. Langerhans cells reactive with both antibodies were located in the parabasal to upper spinous layers. At all ages studied, the number of CD1a positive cells was 10-20% higher than that of HLA-DR. In particular, the number of CD1a positive Langerhans cells in the gingival mucosa was significantly different between subjects in their twenties and those in their sixties (P<0.05). On the other hand, significant differences in the number of HLA-DR positive cells was confirmed between subjects in their twenties and those in their forties or above (P<0.05).
This suggests that the local immume response of human gingival mucosa associated with Langerhans cells may decline with aging.