Crotoxin Isolated from Crotalus durissus terrificus Venom Modulates the Functional Activity of Dendritic Cells via Formyl Peptide Receptors

Figure 1

Effect of CTX and its CA and CB subunits on DC maturation in vitro. Immature DCs derived from BALB/c mice bone marrow were stimulated with LPS (250 ng/mL), CTX (250 ng/mL), CA (250 ng/mL), CB (250 ng/mL), and CTX/CB/CA + LPS (250 ng/mL + 250 ng/mL) or maintained in culture medium for 18 h. Afterwards, the expression of CD40, CD80, CD86, and MHC-II was assessed by flow cytometry. Firstly, the cells were gated based on size and granularity using forward scatter (FSC) versus side scatter (SSC) to start the analysis (a). Single cells and aggregates were also identified by plotting the FSC width versus FSC area to eliminate debris and clumped cells (b). The representative overlaid flow cytometric histogram shows the expression of MHC-II in DCs stimulated with LPS (black line) or LPS + CTX (dotted line) compared with the cells incubated with isotype control mAb (gray background). The expression of CD40 (d), CD80 (e), CD86 (f), and MHC-II (g) on DCs is showed as the mean fluorescence intensity (MIF) of the samples in quadruplicate ± SD. The results are representative of three independent experiments. Statistical analyses were performed by one-way ANOVA, followed by Tukey’s test (GraphPad Prism 5.0, GraphPad Software). —DCs incubated with LPS compared with DCs maintained in culture medium or incubated with CTX, CB, or CA. —DCs incubated with LPS + CTX or LPS + CB compared with the LPS group. —DCs incubated with CTX or CB compared with DCs maintained in culture medium.

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