Figure 2.

Spatial distribution of quiescent and proliferative ILCs within vascular and tissue compartments. (A) Experimental outline. Intracellular Ki67 staining of human ILCs was performed in HSPC-engrafted MISTRG mice after (IV) injection of anti-human CD45-PE antibody to label intravascular human hematopoietic cells. Human cells in the organ vasculature are stained by the IV-injected anti-CD45 antibody (IV CD45-PE), whereas cells residing in the tissue are not stained. Following intravascular labeling, cells were surface-stained ex vivo and stained intracellularly with an antibody against Ki67. Then quiescent (Ki67^-) and proliferative (Ki67⁺) as well as intravascular (IVCD45-PE⁺) and extravascular ILCs within tissue (IVCD45-PE^-) were distinguished by flow cytometry. (B) Flow cytometry analysis of intravascular versus extravascular and quiescent versus proliferative CD117^-CRTH2^- ILC1s, CRTH2⁺ ILC2s, and CD117⁺ ILC3s in the indicated organs of HSPC-engrafted MISTRG mice. ILCs were gated as human CD45⁺CD127⁺CD94^-CD3^-TCRαβ^-Lin^- cells as in Supplementary Figure 1 and as CD34^- cells. (C) Frequencies of quiescent tissue-resident (Q-R), quiescent intravascular (Q-IV), proliferative tissue-resident (P-R), and proliferative intravascular (P-IV) human ILC1s, ILC2s, and ILC3s in the indicated organs (n = 6-11) as determined in (B). n.s., not significant; *, P <0.05; **, P <0.01; ***, P <0.001; ****, P <0.0001 by one-way ANOVA, Tukey’s post-test. Data represent mean ± SEM and are representative of two independent experiments using MISTRG mice engrafted with different pools of HSPCs. (A) was created with Mind the Graph.