Figure 2. JAM3 promotes the self-renewal of LICs through enhanced cell cycle entry.

(A) Representative flow cytometric analysis for WT and Jam3-null L-GMP cells of the recipients upon the secondary transplantation. (B) Quantification of frequencies of L-GMP cells in A (n = 3; ***P < 0.001, Student’s t test). (C and D) Survival data for recipient mice receiving WT or Jam3-null L-GMP cells upon the second to third transplantation (n = 5; **P < 0.01, log-rank test). (E–G) Representative images of colony formation of WT and Jam3-null YFP⁺Mac-1⁺c-Kit⁺ LICs of the secondary recipients in the first plating (E). The colony numbers (F) and total cell numbers of colonies in E (G) were counted (n = 3; ***P < 0.001, Student’s t test). (H–J) Representative images of colony formation of WT and Jam3-null leukemia cells clonogenically derived from the first plating (H). The colony numbers (I) and total cell numbers of colonies in H (J) were calculated (n = 3; ***P < 0.001, Student’s t test). (K) Cell cycle status was determined in WT and Jam3-null YFP⁺Mac-1⁺c-Kit⁺ LICs of the secondary recipients. (L) Quantitative analysis of the cell cycle distribution in K (n = 4–6; ***P < 0.001, 2-way ANOVA followed by Bonferroni’s post-test). (M) CFSE-labeled WT and Jam3-null leukemia cells of secondary recipients were transplanted and analyzed for the homed CFSE⁺ cells in the recipients’ BM and spleen (n = 5–6). (N) WT and Jam3-null leukemia cells of secondary recipients were transplanted into the recipient mice by intratibial injection, followed by the examination of leukemia cells 2 weeks later (n = 5; ***P < 0.001, Student’s t test). (O) Representative flow cytometric analysis of apoptosis of WT or Jam3-null YFP⁺Mac-1⁺c-Kit⁺ LICs. (P) Quantification of data in O (n = 4). Experiments were conducted 3–5 times for validation.