Oral Presentation International Veterinary Immunology Symposium 2016

Response of porcine B cells in the peripheral blood to stimulation with Toll-like receptor ligands (#65)

Roman Othmar Braun 1 2 , Sylvie Python 1 , Gaël Auray 1 , Artur Summerfield 1
  1. Institute of Virology and Immunology, Mittelhäusern, Switzerland
  2. Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland

Antibodies provide crucial protection against many pathogens. To induce plasma cells and the development of memory B cells, not just binding of antigen, but also other signals are known to be crucial. Toll-like receptors (TLR) are known to be expressed on human and murine B cells and can directly trigger their activation. Considering that little is known about porcine B cells, the present study isolated peripheral mononuclear cells and CD21 positive B cells followed by stimulation with TLR ligands. We also determined the expression levels of TLRs at the transcriptional level. We show that porcine B cell can induce upregulation of activation markers such as CCR7 and CD1, as well as proliferation after stimulation with TLR 2, 3, 4, 7, 8 and 9 ligands. These effects were not dependent on bystander cells as they were also observed with purified B cells. Interestingly, a particular strong reactivity was found with TLR2 and TLR8 ligands, although the corresponding TLR’s were not those with the highest expression. We also demonstrate that innate responses in B cells were observed with different B cell subsets defined on their IgM, CD21, CD1 and CD2 expression. This knowledge will be of value for defining strategies to manipulate B cells responses, in particular using vaccines.