TY - EJOU AU - CABRAL, IVÓN TERESA NOVAK, HUMBERTO RAMÓN TI - Rosette formation by macrophages with adhered T lymphocytes is precluded by inhibitors of antigen processing and presentation T2 - BIOCELL PY - 2008 VL - 32 IS - 2 SN - 1667-5746 AB - We had previously found in autologous human leukocyte cultures, in which dead neutrophils phagocytosis by macrophages occur, macrophages and T CD4 lymphocytes perform a selective cell-cell interaction showing many figures of either one, two or several T- lymphocytes adhering to a central macrophage were seen. Considering that antigen presentation would be necessary for the formation of these immune synapses, we attempted to block rosette formation (i.e., the formation of macrophage associations with at least three lymphocytes) by interfering with both antigen processing and presentation. Culture samples of autologous leukocytes from 7 healthy donors were subjected to either brefeldin A, chloroquine or to an antiHLA DR antibody. Rosette formation was significantly inhibited in the treated samples (either with brefeldin A, chloroquine or the anti- HLA DR; ANOVA, p<0.001, as compared with the untreated controls). It is concluded that interference with antigen processing and presentation precludes the formation of these cellcell interactions. KW - autologous rosetting KW - cultured human macrophages and T- lymphocytes KW - brefeldin A KW - chloroquine KW - immune synapses DO - 10.32604/biocell.2008.32.169