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Lymphatics and lymphangiogenesis in the eye
Shintaro Nakao1, Ali Hafezi-Moghadam, Tatsuro Ishibashi
1Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka 812-8582, Japan.
Journal of Ophthalmology
|April 24, 2012
Summary
The eye possesses lymphatic vessels and lymphangiogenesis, crucial for fluid balance and immunity. Understanding these ocular lymphatics offers new therapeutic avenues for preventing vision loss in eye diseases.
Area of Science:
- Ophthalmology
- Immunology
- Vascular Biology
Background:
- Lymphatic vessels are vital for tissue fluid balance and immune function.
- Lymphangiogenesis, the formation of new lymphatic vessels, is implicated in disease pathogenesis, including tumor metastasis and inflammation.
- Historically, the eye was believed to lack lymphatic vessels, except in the conjunctiva.
Purpose of the Study:
- To review the current understanding of lymphatic vessels and lymphangiogenesis within the eye.
- To highlight the presence and potential functions of ocular lymphatics.
- To emphasize the role of ocular lymphatics in disease and potential therapeutic strategies.
Main Methods:
- Review of recent scientific literature on ocular lymphatics.
- Identification of lymphatic endothelial markers (e.g., LYVE-1, podoplanin) and lymphangiogenic factors (e.g., VEGF-C).
- Analysis of studies investigating lymphatic presence in ocular tissues like the cornea, ciliary body, and choroid.
Main Results:
- Lymphatic vessels have been identified in the corneal limbus, ciliary body, lacrimal gland, orbital meninges, and extraocular muscles.
- The choroid may possess a lymphatic-like system, and the uveolymphatic pathway might contribute to ocular fluid homeostasis.
- Lymphangiogenesis plays a role in ocular conditions such as corneal transplant rejection and tumor progression.
Conclusions:
- Advances in identifying lymphatic markers and factors have revealed the existence and significance of ocular lymphatics.
- While ocular lymphatic outflow is not fully understood, these vessels are involved in ocular fluid balance and disease.
- Further research into ocular lymphatics and lymphangiogenesis is essential for developing novel treatments for vision-threatening eye diseases.
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