Mean recombination activity of mutant RAG alleles and colonic inflammation in pRD. (A) Recombination activity of variants in the cohort of pRD patients with (n = 5) and without IBD (n = 11). Statistical analysis was performed using a Mann–Whitney test. (B) Immunohistochemical analysis of colon biopsy isolated from P2, showing anti-CD3 staining and CXCL9 transcript by in situ hybridization. All images are 10× magnification (scale bars: 100 μm).