RESUMO
The formation of the rich cellular features of MGCs, where the nuclei are arranged circularly at the periphery of the cell (morphologically epithelioid; Langhans-type), is assumed to be associated with any granulomatous disease. The mechanism by which TNF controls the formation of human MGCs in vitro was investigated, focusing on the effect of the TNF-neutralizing antibody. Peripheral blood monocytes were isolated with mAb-coated immunologic magnetic beads and cultured for 10 days in the presence of 20 ng/mL GM-CSF and 10 ng/mL IL-4. These cells were further incubated in the presence of TNF-α with/without its blockade antibodies for 14 days. Myeloid DCs can be generated from peripheral blood monocytes, and both IL-4 and GM-CSF can provide sufficient stimulus for their differentiation. The formation of MGC can be induced in the presence of TNF-α. This reaction was prohibited by the presence of the TNF-neutralizing antibody but not by the presence of anti-TNF receptor II antibody. The activation of Rho and focal adhesion kinases induced by TNF-α stimulation might be linked to cell assembling and the formation of Langhans-type MGCs. MGCs can produce only small amounts of superoxide anions compared to isolated macrophages such as myeloid DCs.
