T-cell co-stimulation pathways (IMAGE) Medical University of South Carolina Caption This figure depicts the two major T-cell co-stimulation pathways, ICOS and CD28, targeted by the new drug candidate ALPN-101 as compared to CTLA-4-Fc CD28/B7 pathway inhibitors (abatacept and belatacept) for the treatment of graft-versus-host disease. Credit Alpine Immune Sciences Usage Restrictions Image may only be used with appropriate caption or credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.