An Id2^RFP-Reporter Mouse Redefines Innate Lymphoid Cell Precursor Potentials

Area of Science:

• Immunology
• Cell Biology
• Developmental Biology

Background:

• Current models propose distinct developmental pathways for innate lymphoid cells (ILCs), segregating natural killer (NK) cells from helper ILCs (ILC1, ILC2, ILC3).
• These pathways are thought to be regulated by key transcription factors including Id2, Zbtb16, and Gata3.

Purpose of the Study:

• To re-examine the phenotype and function of ILC precursors (ILCPs) using a novel Id2-reporter mouse model.
• To clarify the cell-fate potential of ILCPs and refine the model of ILC differentiation.

Main Methods:

• Development of a novel Id2-reporter mouse strain expressing red fluorescent protein (RFP) to track Id2 expression.
• Utilized multiplexing of Id2^RFP with Zbtb16^CreGFP and Bcl11b^tdTomato reporter strains for single-cell analysis.
• In vivo and in vitro functional assays to assess ILCP potential.

Main Results:

• Bone marrow ILCPs exhibit heterogeneity and possess significant NK-cell potential.
• Id2⁺Zbtb16⁺ ILCPs are multipotent and retain NK-cell potential, challenging the notion of strict lineage segregation.
• Distinct expression of Zbtb16 and Bcl11b defines late-stage ILC2 and ILC3 precursor populations.

Conclusions:

• The study presents a revised model for innate lymphoid cell differentiation.
• This revised model redefines the cell-fate potential of ILCPs, particularly Zbtb16⁺ precursors, highlighting their multipotency.
• Findings emphasize the plasticity of early ILC development, with ILCPs capable of contributing to both NK and helper ILC lineages.