BTLA and infection: The treatment with the mAb one day before infection and again at day 2 p.i. (Figure 7C), or at days 4 and 6 p.i. (Figure S4A), led to reduced numbers of OVA-specific CD8+ T cells at day 70 p.i. Injection of the anti-BTLA antibody at days 8 and 10 after LM-OVA infection also led to reduced numbers of memory CD8+ T cells, further suggesting a role for HVEM-BTLA interaction during the contraction phase of the immune response (Figure S4B).