Immunohistochemical Characterization of Dendritic Cells after Systemic Administration of Staphylococcal Enterotoxin B / 대한해부학회지

ABSTRACT

This study was performed to investigate the effects of Staphylococcal enterotoxin B (SEB) on dendritic cells (DCs) and other immune cells in the major lymphoid organs. A single dose of SEB (25 microgram/kg) was administered to BALB/c mice by intraperitoneal injection. After the mice were sacrificed in groups of three at 2 h, 6 h, 1 day, 2 days, 3 days, 1 week and 2 weeks, the spleen, lymph node and thymus were removed. The immunocytochemical characterization of the cells was carried out using various monoclonal antibodies in cryostat-cut sections. We demonstrated in this study the distribution patterns of DCs and their major costimulatory and adhesive molecules in the murine spleen, lymph node and thymus after SEB administration. We obtained the evidence for maturation of DCs in vivo in response to SEB. DCs were found in increased number in the periarterial lymphatitc sheath (PALS) of spleen, paracortex of lymph nodes and thymic medulla. CD86, ICAM-1 and MHC class II molecules were upregulated on the activated and matured DCs after SEB injection. The most salient feature of the present study was the differential expression pattern of the costimulatory and adhesive molecules on the activated DCs. In addition to DCs, T cells expressing T cell receptor Vbeta8 were increased in number after SEB treatment. In conclusion, SEB exhibited a potent and effective stimulative effect on DCs in vivo.