Research Information System
6th International Molecular Immunology & Immunogenetics Congress (MIMIC-VI), İstanbul, Turkey, 27 - 30 April 2025, pp.99, (Summary Text)
known as brucellosis. The formation of exosomes in cells can alter immune responses during
infection. Brucella can hide itself in phagocytic cells. In our study, the macrophage polarization of
monocyte/macrophage-derived exosomes exposed to Brucella bacteria and bacteria-derived outer
membrane vesicles (OMVs) was examined.
Method: In our study, THP-1 cells (human monocytic cell line) were cultured separately with
inactive Brucella melitensis and Brucella abortus for 48 hours. Exosomes were isolated from THP-1
cells treated with inactive Brucella species using the ultracentrifugation method (100,000xg +4°C).
The concentrations of the exosomes were determined using BCA (Bicinchoninic Acid Assay). The
isolation of OMVs from live Brucella species was conducted using a commercial isolation kit. THP-1
cells were infected with active Brucella species. The cells were treated with
inactive Brucella species, Brucella-derived THP-1 exosomes, and bacteria-derived OMVs (each
20ug). After 48 hours of incubation under the conditions, the cells (CD80, CD86, HLA-DR, CD163,
CD169, CD206) were analyzed using a flow cytometer.
RESULTS-Conclusion: In conclusion, an increase in CD80-CD86 levels was observed in cells
infected with active Brucella species, exposed to inactive Brucella-derived THP-1 exosomes, and
exposed to active Brucella OMVs. A statistically significant increase in CD169 levels of the cells was
observed, with this increase being less pronounced in THP-1 cells treated with OMV compared to
those treated with active Brucellaspecies. It has been shown that exosome and OMV structures
also exhibit a significant increase in surface markers; however, this increase is less pronounced
compared to the increase directly induced by bacteria. ROS-NO levels of cells decreased at the
same time.