Distribution of class I and II human leukocyte antigens in the larynx.

Objective: To examine the antigenic distribution of human leukocyte antigens (HLA) of the human larynx.
Study Design and Setting: Twelve human larynges were examined for Class I (HLA-A, -B, -C) and Class II (HLA-DR) histocompatibility antigens using mouse monoclonal antibodies in an indirect immunoperoxidase assay. Structures of the larynx and surrounding tissues were examined and given a semiquantitative score based on HLA Class I and II expression.
Results: The mucosal surface epithelium of the larynx stains 2+ or stronger for HLA Class I antigens and 1+ for Class II antigens. The deeper submucosal glands stain 1+ for Class I antigens and 2+ or stronger for Class II antigens. Thyroid cartilage showed 2+ or stronger staining of the chondrocytes for Class I antigens only. Thyroid follicular cells also stain only for Class I antigens. Perichondrium and Schwann cells of nerves stain stronger for Class I antigens than Class II antigens. Cartilage matrix, muscle cells, and axons of nerves do not stain for either class of antigens. Endothelium stains 3+ for both classes of antigens.
Conclusions: The detailed distribution of major transplantation antigens in the human larynx is elucidated. Class II antigens implicated as initiators of organ transplant rejection were primarily found in 6 areas: mucosal surface epithelium, submucosal glands, ducts, vascular endothelium, perichondrium, and Schwann cells of nerves. The relevance of these findings to the initiation and detection of laryngeal allograft graft rejection is discussed.