RT - Journal Article T1 - The Immunomodulatory Effect of Recombinant Exotoxin A of Pseudomonas Aeruginosa on Dendritic Cells Extracted from Mice Spleen JF - JABS YR - 2014 JO - JABS VO - 4 IS - 4 UR - http://jabs.fums.ac.ir/article-1-508-en.html SP - 436 EP - 445 K1 - Exotoxin A K1 - Dendritic cell K1 - Immunomodulatory effects AB -  Background & Objective: Dendritic cell (DC) is as a key cell in activation of immune response against microbes and disease. Therefore, the effect of recombinant exotoxin A of Pseudomonas aeruginosa on the maturity and the activation of DCs was evaluated in this study. Materials & Methods: Recombinant exotoxin A was produced from Pseudomonas aeruginosa DNA. MTT assay was used to evaluate the cytotoxicity of this protein on DCs. The expression of co-stimulatory molecules CD40, CD86, and MHCΠ was evaluated by flow cytometry. Moreover, the effect of this antigen (Ag) on T-cell proliferation was evaluated using Mixed Lymphocyte Reaction (MLR) assay and the secretion of IL-4 and IFN- γ. Secretion of IL-12 by DCs was measured with Enzyme-Linked Immunosorbent Assay (ELISA) method. The data were collected and analyzed with one way ANOVA test. Results: Recombinant exotoxin A had no effect on DCs viability. In addition, expression of CD40, CD86, and MHCΠ did not change significantly compared to the negative control cells. Moreover, T-cells proliferation was decreased significantly at the concentration of 0.1µg/ml of this Ag. The secretion of IL-12 was increased by DCs, in contrast the secretion of IL-4 and IFN-γ in MLR supernatant did not decrease significantly. Conclusion: Exotoxin A decreases the proliferation of T-cells and also leads to a change in the pattern of cytokine secretion of immune cells.   LA eng UL http://jabs.fums.ac.ir/article-1-508-en.html M3 ER -