Figure 5.

Priming of naive T cells in situ with antigen-pulsed murine fibrocytes. Purified BALB/c mouse fibrocytes were cultured for 3 days without (NO PULSE), or with 50 μg/ml of p24 (p24 PULSE), or gp120 (gp120 PULSE) in DME/20% FCS, washed, and injected i.d. (5 × 10⁴ cells) into the right rear footpad. The proximal popliteal lymph nodes were explanted 5 days later, dissociated, and cultured with PBS or 50 μg/ml of p24 or gp120 for 72 hr. To verify the proliferating cell type, CD4⁺ T cells were depleted by immunomagnetic selection just prior to liquid scintillation counting (p24-CD4, gp120-CD4). 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.