Fig. 2

Stimulation with the bacterial superantigen SE D activates V3-21 ⁺ B cells which are nonresponsive to anti-CD3-driven T cells

B cells were isolated from the peripheral blood of three donors and cocultured with either anti-CD3-activated LAB1-10 T cells or LAB1-10 and SE D. Cells were harvested after 20 days. cDNA was amplified with VH3- and IgM-specific primers and the concentration of V3-23 and V3-21 transcripts were semiquantified as described in Fig. 1. V3-23⁺ B cells were activated by both, anti-CD3-stimulated as well as superantigen-stimulated T cells. V3-21⁺ B cells were nonresponsive to anti-CD3-driven T helper cells but responded in the presence of SE D. (■, Donor 1; ▨, Donor 2; □, Donor 3).