CpG Inhibits Pro-B Cell Expansion through a Cathepsin B-Dependent Mechanism.

Ana Inés Lalanne (1) , Ignacio Moraga (2) , Yi Hao (3) , João Pedro Pereira (1) , Nuno L. Alves (4) , Nicholas D. Huntington (4) , Antonio A. Freitas (3) , Ana Cumano (1) , Paulo Vieira (1)

1 Développement des Lymphocytes
2 Signalisation des Cytokines - Cytokine Signaling
3 Biologie des Populations Lymphocytaires
4 Cytokines et Développement Lymphoïde

TLR9 is expressed in cells of the innate immune system, as well as in B lymphocytes and their progenitors. We investigated the effect of the TLR9 ligand CpG DNA on the proliferation of pro-B cells. CpG DNA inhibits the proliferation of pro-B, but not pre-B, cells by inducing caspase-independent cell death through a pathway that requires the expression of cathepsin B. This pathway is operative in Rag-deficient mice carrying an SP6 transgene, in which B lymphopoiesis is compromised, to reduce the size of the B lymphocyte precursor compartments in the bone marrow. Thus, TLR9 signals can regulate B lymphopoiesis in vivo.

Domains: Life Sciences [q-bio]; Immunology

Ana Inés Lalanne, Ignacio Moraga, Yi Hao, João Pedro Pereira, Nuno L. Alves, et al.. CpG Inhibits Pro-B Cell Expansion through a Cathepsin B-Dependent Mechanism.. Journal of Immunology, 2010, epub ahead of print. ⟨10.4049/jimmunol.0903854⟩. ⟨pasteur-00481956⟩