Related Experiment Videos
Lymphocyte emigration from high endothelial venules in rat lymph nodes
Immunology
|November 1, 1976
Summary
Lymphocyte adhesion to high endothelial venules (HEV) involves microvillar attachment to endothelial cells. This process, crucial for immune cell trafficking, is influenced by surface glycoproteins and endothelial glycocalyx.
Area of Science:
- Immunology
- Cell Biology
- Microscopy
Background:
- Lymphocyte trafficking is essential for immune surveillance.
- High endothelial venules (HEVs) are specialized blood vessels facilitating lymphocyte entry into lymphoid tissues.
Purpose of the Study:
- To elucidate the sequential events of lymphocyte emigration from HEVs.
- To characterize the cellular and molecular interactions during lymphocyte extravasation.
Main Methods:
- Scanning and transmission electron microscopy.
- Regional perfusion techniques.
- Biochemical disruption of cell surface components.
Main Results:
- Lymphocytes initially adhere to HEVs via microvilli engaging with endothelial cell surface pits.
- Adhesion is sensitive to treatments affecting endothelial glycocalyx, lymphocyte glycoproteins, and divalent cations.
- Migrating lymphocytes exhibit a motile configuration and cytoplasmic polarity, moving along chemotactic gradients.
Conclusions:
- Lymphocyte emigration from HEVs is a multi-step process involving specific adhesion mechanisms.
- The findings provide insights into the dynamic interactions governing lymphocyte diapedesis.
- Chemotaxis likely directs lymphocyte migration into lymphoid tissues.