The ADA1 isoform, present extracellularly in plasma/serum, mediates T cell costimulation via binding to CD26 (its cognate receptor on T lymphocytes).[46, 47] CCL23, with both pro- and anti-cancer properties, is produced by eosinophils, monocytes and MDSCs activated by IL-1β [48]. The gene discussed is IL1B; the disease is cancer.