Portal de Periódicos da CAPES

An immuno-electron microscopic study on interactions among dendritic cells, macrophages and lymphocytes in the human palatine tonsil.

1989; International Society Histology & Cytology; Volume: 52; Issue: 3 Linguagem: Inglês

10.1679/aohc.52.231

1349-1717

Shuichiro Okato, Sumiko Magari, Yūzō Yamamoto, Masahiro Sakanaka, Hiroaki Takahashi,

Antimicrobial Peptides and Activities

The sites of interaction between antigenpresenting cells (dendritic cells, macrophages) and lymphocytes in the human palatine tonsil were investigated by pre-embedding immuno-electron microscopy and acid-phosphatase histochemistry. Used in this study were: an S-100 protein antiserum recognizing Langerhans cells and interdigitating cells, OKT6 monoclonal antibody reacting with surface antigens of Langerhans cells, and Leu-3a monoclonal antibody directed to surface antigens of helper-T-cells.In the stratified squamous epithelium, Langerhans cells with characteristic rod-shaped or racket-shaped Birbeck granules exhibited S-100 protein and OKT6 immunoreactivites, and frequently extended long processes to adjacent lymphocytes. The subepithelial area contained a significant number of macrophages, some of which were closely apposed to interdigitating cells with S-100 protein immunoreactivity. Occasionally, macrophages with acid-phosphatase-positive phagosomes and/or lysosomes extended short processes to neighboring lymphocytes. In the interfollicular area, some interdigitating cells and a few Langerhans cells were seen in proximity to or in contact with lymphocytes stained with the Leu-3a antibody.These findings support previous in vitro studies suggesting the induction of T-cell activation by antigenpresenting cells. They further indicate that T-cell activation by the individual antigen-presenting cells takes place in different areas of the human palatine tonsil through a variety of cell-to-cell interactions.