B-CD8+ T Cell Interactions in the Anti-Idiotypic Response against a Self-Antibody
B-1a cells from P3 mAb-immunized BALB/c mice were capable to induce in vitro CD8+ T cell activation. (a) Peritoneal B-1a cells derived from BALB/c mice, immunized with a single dose of P3 or control IgM mAb, were incubated with naïve CD8+ T cells for three days. The expression of activation or functional markers by CD8+ T cells was measured by flow cytometry, directly for CD25, CD107a, and CD69 or after an intracellular staining protocol for IFN-γ and granzyme B (GZMB). (b) Peritoneal B-1a cells derived from BALB/c mice immunized with a single dose of P3 mAb were incubated with CD8+ T cells for three days, and 100 μg/mL of P3 mAb or control isotype antibody was added to the culture medium. After 72 h, the expression of activation and functional markers by CD8+ T cells was measured as above. Contour plots show a representative result. Columns represent means ± SD of the values obtained in triplicate,, Mann–Whitney U test.