THE DERMAL DENDROCYTE

Dermal dendrocytes represent a population of resident cells of the der mis identified recently by virtue of the immunohistochemical expressio n of the coagulation factor XIIIa (fXIIIa). These dendritic cells of b one-marrow origin bear particular histoenzymatic and immunohistochemic al features, some of which are shared with antigen-presenting cells; h owever, they are clearly distinct from epidermal Langerhans cells. Der mal dendrocytes could act as macrophages, antigen-presenting cells or participate in the homeostasis of macromolecules of the dermis. These cells give rise to some cutaneous tumours and seem involved in inflamm atory dermatoses where they act by means of cytokine production ; they could even represent targets of HIV infection. Future functional stud ies will hopefully lead to a better understanding of their precise rol e in normal and diseased skin, which remains presently partly speculat ive.