Figure 4. LXB₄ enhances cyclooxygenase-2 (COX2) expression in B cells.

CD19+ B cells from healthy individuals were pretreated with LXB₄, and then stimulated with the memory B cell-inducing cocktail (MBCC) for the indicated length of time. (A) The kinetics of COX2 protein expression in B cells stimulated with the memory B cell-inducing cocktail without any other treatments was assessed using western blot. One representative western blot is shown of 3 donors tested. (B) Changes in total COX2 protein levels with LXB₄ were measured at day 6 post-stimulation in 4 different donors. One representative western blot is shown, the densitometry is mean ± SEM for 4 donors. Data analyzed by RM one-way ANOVA with Tukey’s posttest, *p≤0.05. (C) B cells were subjected to intracellular staining for COX2 followed by flow cytometric analysis. The gating strategy is shown. The percentage of B cells expressing COX2 and mean fluorescence intensity for COX2 staining was determined. In the diagram, black dots represent B cells stimulated without any treatment, and gray dots represent B cells pretreated with LXB₄ and stimulated. Data shown from one representative donor of 4 donors tested.