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Updated: Jun 24, 2025
08:39
Quantifying Leukocyte Egress via Lymphatic Vessels from Murine Skin and Tumors
Published on: January 7, 2019
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Fluid dynamics and leukocyte transit in the lymphatic system
Huabing Li1, Jingjing Zhang1, Timothy P Padera2
1Department of Material Science and Technology, Guilin University of Electronic Technology, Guilin 541004, China.
PNAS Nexus
|June 3, 2024
Summary
Cellular movement in lymphatic vessels is complex. This study reveals that contracting vessel walls and gravity significantly impact cell speed and deformation, especially near valves.
Area of Science:
- Biophysics
- Physiology
- Computational Biology
Background:
- The lymphatic system is crucial for fluid balance, immune response, and cancer metastasis.
- Understanding cellular transport within lymphatic vessels is vital for various physiological and pathological processes.
Purpose of the Study:
- To investigate cellular movement in a contracting lymphatic vessel using a computational model.
- To compare transient flow dynamics with steady flow in lymphatic vessels.
- To analyze the influence of vessel contraction, valves, and gravity on cell dynamics.
Main Methods:
- Developed a 2D lattice Boltzmann-based computational model.
- Simulated cells transported within a contracting lymphatic vessel with bi-leaflet valves.
- Incorporated autonomous vessel wall contractions regulated by calcium and nitric oxide levels.
- Analyzed the effect of vessel orientation with respect to gravity.
Main Results:
- Cells move faster than average fluid velocity during active vessel contraction.
- Fluid forces induce significant deformation in compliant cells, particularly near valves.
- Vessel orientation relative to gravity modulates cellular motion by affecting contraction dynamics.
- Gravity's influence persists even for neutrally buoyant cells.
Conclusions:
- Cellular motion in lymphatic vessels is significantly influenced by transient, contractility-driven flows.
- The complex flow environment near valves plays a critical role in cellular transport and deformation.
- Computational modeling provides valuable insights into the biomechanics of lymphatic cellular transport.
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