rLIF administration protects ISCs from GVHD-induced damage. Administration of rLIF significantly increased the number of proliferating crypts (A) and viable ISCs (B) in B6C3F1 mice at 2 days after allo-BMT. (A-B, upper) Representative images of immunohistochemistry staining of Ki67 (A) and Olfm4 (B) in the duodenum and ileum tissues. (A-B, lower) Quantification of viable crypts per field (A) and Olfm4-positive crypts per field (B) in the duodenum and ileum of mice after allo-BMT. n = 30 fields from at least 3 mice/group. (C) IFNγ induced cell death in intestinal organoids derived from B6C3F1 mice, which was largely decreased by rLIF. Representative images of organoid growth (left). Quantification of organoid viability (right). n = 4/group. Data are presented as mean ± standard deviation. ∗∗∗P < .001, n.s.: not significant. Student t test.