NRP1 and systemic lupus erythematosus: Interestingly, disease in MRL.LPR is also associated with an increase in unusual CD4−CD8− T cells, a feature which leads to the severe lymphadenopathy in this model, but is not observed in human SLE (Morse et al, 1982; Cohen & Eisenberg, 1991); we observed that these cells were mostly PD‐1+, but only marginal NRP1 upregulation (Fig EV4G).