Inhibition of T-Cell Expansion Caused by Inducible Costimulator/B7h Costimulation Blockade in Direct Allorecognition Pathway

• DOI: 10.1016/j.transproceed.2011.09.044
• Publication Date: 2011-12-14T00:27:57Z
• Authors: J.F. Du; Q.-Y. Li; X.Q. Ji; G. Chen; X. Bai; F.-Y. Zuo; B. Yu
• Keywords: Allorecognition

Inducible costimulator (ICOS)/B7h costimulation plays a crucial role in acute and chronic allograft rejection. To test the role of the ICOS signal in T-cell activation and expansion, we used ICOS-Fc-targeted B cells as donor antigen presenting cells to challenge the allogeneic response in vitro.In vitro, the binding of ICOS-Fc with B7h on splenic B cells was confirmed by flow cytometry analysis. To evaluate the capacity of ICOS-Fc-targeted B cells to elicit an allogeneic response in vitro, we performed mixed lymphocyte reactions.The binding of B7h on splenic B cells by ICOS-Fc was confirmed at a saturating concentration of 100 μg/mL. Blockade of ICOS/B7h in direct allorecognition depressed proliferation of alloreactive T cells in vitro.ICOS/B7h signal plays an important role in direct allorecognition, eliciting allogeneic responses in vitro.