CTLA4 and cancer: This included B cells from healthy controls (HC, n = 8), patients with cancer treated with ICB (ICB, n = 8) and patients with NFKB1 or CTLA4 haploinsufficiency (IEI, n = 4), together with a published set of single B cell transcriptomes from patients with systemic lupus erythematosus (SLE, n = 3)33.