Dendritic cells with antigen-presenting capability reside in airway epithelium, lung parenchyma, and visceral pleura.

TLDR

The study identifies a population of dendritic cells present throughout human and mouse pulmonary tissues, including trachea, bronchi, alveoli, and visceral pleura. The authors identified these DC by histological examination of human and mouse lung tissues. The identified DC express HLA‑DR, T200, Ia, Fc‑IgG, and C3bi receptors, lack nonspecific esterase staining, resemble Langerhans cells, and are capable of antigen presentation, indicating a role in pulmonary immune responses.

Abstract

In this study, we identified a population of dendritic cells (DC) that exists throughout human and mouse pulmonary tissues, including the trachea, bronchi, alveoli, and visceral pleura. In human tissue, these DC were shown to be positive for HLA-DR and T200 antigens. In the mouse, the DC expressed not only Ia and the T200 antigen, but also Fc-IgG and C3bi receptors. Unlike alveolar macrophages, the DC were negative for nonspecific esterase staining and shared ultrastructural similarities with the DC described by Steinman (1), and with Langerhans' cells, even though they did not contain Birbeck granules. We were able to demonstrate that mouse pulmonary DC function in antigen presentation, as observed with the other DC. Thus, the respiratory tract contains DC that are capable of functioning in antigen presentation and that may be important in pulmonary immune responses.