Related Experiment Videos
Requirement for membrane lymphotoxin in natural killer cell development.
K Iizuka1, D D Chaplin, Y Wang
1Departments of Internal Medicine and Pathology, Howard Hughes Medical Institute, and Center for Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
Summary
Lymphotoxin (LT) is crucial for natural killer (NK) and NK/T cell development. This study reveals LT signals are essential for these immune cells
Area of Science:
- Immunology
- Cell Biology
- Developmental Biology
Background:
- Natural killer (NK) cell development relies on bone marrow microenvironment interactions.
- The specific molecular signals governing NK cell development are not fully understood.
Purpose of the Study:
- To investigate the role of lymphotoxin (LT) in NK and NK/T cell development.
- To elucidate the molecular mechanisms underlying NK cell development within the bone marrow microenvironment.
Main Methods:
- Utilized LTalpha-/- mice to assess NK and NK/T cell populations and function.
- Performed reciprocal bone marrow transfers between LTalpha-/- and wild-type mice.
- Investigated the role of Interleukin-15 (IL-15) in LT-deficient conditions.
Main Results:
- LTalpha-/- mice exhibited significantly reduced NK and NK/T cell numbers and impaired function.
- Tumor necrosis factor receptor-deficient mice showed normal NK and NK/T cell development, indicating TNFRs are not essential.
- Bone marrow transfers demonstrated the necessity of membrane LT-expressing NK cell precursors interacting with stromal cells for development.
- LT-deficient cells produced IL-15 upon activation, suggesting LT acts upstream or independently of IL-15 in NK cell development.
Conclusions:
- Membrane lymphotoxin (LT) plays a critical, novel role in NK and NK/T cell development.
- NK cell precursors signal through membrane LT to induce the microenvironment, promoting their own development.
- This identifies a new pathway involving LT and cell-cell interactions in immune cell development.