Figure 6.

Requirement of shared MHC haplotype between priming fibrocyte and restimulation APC. DBA-2 × C3H/HeJ F₁ mice (H-2^dxk) were injected with antigen-pulsed fibrocytes from either parent strain DBA-2, H-2^d (d) or C3H/HeJ, H-2^k (k). Five days later, the proximal popliteal lymph node cells were isolated and depleted of endogenous class II MHC⁺ APCs by immunomagnetic selection. APC-depleted lymph node cells (1 × 10⁵) then were cocultured with 1 × 10⁵ mitomycin C-treated F₁ (dxk) or parental spleen cells (d or k) as restimulation APCs, with or without gp120. The proliferative activity was measured over the last 12 hr of culture by [³H]thymidine incorporation. Data are expressed as mean ± SD and are representative of one experiment that was performed three times.