Figure 4.

Transgenic T cells from DO11.10-IL-2^–/– mice help memory but not naive B cells produce antibody. (a) Primary response: SCID mice received 10⁷ naive B cells from non-immunized mice together with 3 × 10⁵ T cells from naive DO11.10-IL-2^–/– mice (IL-2 KO), or from naive conventional DO11.10 mice (KJ) or received no transgenic T cells. All recipients were challenged with 100 μg ap-OVA on the day of transfer. Values represent the geometric means + SD of six recipients per group (IL-2 KO versus KJ: *P < 0·05; ***P < 0·001). (b) Secondary response: SCID mice were injected with 10⁷ B cells from OVA-primed mice together with 3 × 10⁵ naive transgenic T cells from DO11.10-IL-2^–/– (IL-2 KO), or DO11.10 donors (KJ), or 3 × 10⁵ T cells from DO11.10-IL-2^–/– mice plus twice daily injections of 3 × 10⁵ IU rIL-2 per day for 6 days (IL-2 KO + IL-2), or no T cells (pr B cells only). All recipients were challenged with 10 μg sol-OVA on the day of transfer. Values represent the geometric means + SD of six recipients per group.