Figure 5.

BTLA directly affects the function of CD8α⁺ DC s. A) The expression of BTLA and HVEM in CD8α⁻ and CD8α⁺ DC s from naive WT, Btla^−/− and Hvem^−/ mice was analyzed by flow cytometry. B) WT mice were treated with Hamster IgG or anti-BTLA (6A6) Ab and infected i.v. with 1×10⁷ Listeria -OVA thirty minutes later. Sixteen hours after infection, splenic CD11c^loCD8α^loCD11b⁺ granulocyte (PMN) and macrophage (Mφ, including monocytes), CD8α⁺ and CD8α⁻ CD11c⁺ DC populations were purified by flow sorting, and sorted populations were lysed and plated onto BHI agar to determine degree of infection. C) Schematic of the mixed BM chimera experiments. D) WT mice were lethally irradiated (10Gy) and transferred with mix bone marrow (CD45.1 WT and CD45.2 Btla^−/− BM). Two months after reconstitution. Mice were infected i.v. with 5×10⁶ Listeria -OVA. Sixteen hours after infection, indicated sorted cell populations were lysed and plated onto BHI agar to determine degree of infection. E) Sorted CD8α⁺ DCs from WT were infected with Listeria-OVA for 0.5 hour. Free bacteria was removed by Percoll gradient centrifugation. Cell were cultured for another 4 hours in the presence of hamster Ig or anti-BTLA (6A6) Ab. At indicated time, cells were lysed and plated to BHI agar to determine degree of infection. The results are representative of two or three independent experiments, three to five mice in each group and data are represented as mean +/− SEM.