For example anti-PD-1 antibodies have been trialled in solid cancers49 and T-cell lymphomas50 and anti-ICOS antibodies are being investigated in the auto-immune condition, systemic lupus erythematosus51 as well as PTCL (clinicaltrials.gov identifier NCT02520791). This evidence concerns the gene ICOS and mature T-cell and NK-cell non-Hodgkin lymphoma.