For instance, in the human system, CD28 stimulation by either agonistic antibodies or B7 molecules induces the recruitment of several signalling proteins4–6 that in turn cooperate to activate a non-canonical NF-κB2-like cascade7,8 leading to the upregulation of pro-inflammatory cytokine/chemokine genes in healthy individuals as well as in multiple sclerosis (MS) and type 1 diabetes (T1D) patients9,10. This evidence concerns the gene CD80 and type 1 diabetes mellitus.