Purified human oral mucosal Langerhans cells function as accessory cells in vitro

Abstract

SUMMARY Oral mucosal Langerhans cells (OMLC) may have an importanl role in the induction of immune responses to oral pathogens. In this study. anti-HLA-DR antibody-coated immunomagnctic beads were used to purity OMLC from suspensions of normal human buccal epithelium and the capacity of the purified cells to function as accessory cells (AC) was investigated. Electron microscopy was used to show that the purified cells possessed all recognized ultrastructural features previously described in epidermal Langerhans cells. Using T lymphocyte proliferation assays in hanging drop microcult ures, it was found that purified OMLC could function as AC for responses to concanavalin A by autologous T cells. Purification of OMLC from small biopsies of oral mucosa has enabled us to show that OMLC, like epidermal Langerhans cells, can function as AC in vitro.