Figure 4. B cell development in the mediastinal lymph node is affected by CD28 deletion on CD4⁺ T cells.

Blood was collected from reinfected mice by cardiac puncture and centrifuged at 8×g for 10 min in serum separator tubes. (A), Serum antibody titres of N. brasiliensis specific IgG1, IgG2a and total IgE were determined by ELISA. Single cells suspension was prepared from mediastinal lymph nodes and cells stained for flow cytometric analysis. (B), Total number of cytokine producing B220⁺ B cells was determined by intracellular flow cytometric analysis after re-stimulation of total MST cells with 50 ng/ml PMA, 250 ng/ml ionomycin and 200 µM monensin for 4 h at 37°C. (C) Total numbers of CD19⁺B220⁺ B cells population recruited into the mediastinal lymph node. (D)Absolute numbers of different B cell subsets recruited into the draining mediastinal lymph node. B cell subsets were differentiated based on the following markers: follicular B cells (FO, CD19⁺B220⁺CD21^hiCD23^hi) and marginal zone B cells (MZ, CD19⁺B220⁺CD21^hiCD23^lo). Data represents two independent experiments. n = 5–6 mice per group. *P<0.05 and **P<0.01 vs C75BL/6 using One-Way ANOVA with Bonferroni post test.