Name: glycocalyx in cell recognition
Uploaded: 2023-06-23T15:38:44.000Z
Duration: 1 min 14 s
Channel: JoVE

The glycocalyx is a 10 to 100 nanometer thick mesh-like layer on the outer surface of the plasma membrane. It comprises membrane-associated carbohydrates or glycans such as glycoproteins, proteoglycans, and glycolipids.&#160;&#160;
The glycans trap water to form a viscous gel that acts as a molecular sieve, allowing smaller molecules to pass while restricting larger ones.
The glycocalyx plays different roles in cell-cell interactions, like cell recognition, adhesion, and signaling.
Carbohydrate receptors in the glycocalyx, such as lectins, can recognize specific glycan chains on the adjacent cell surface, allowing cell-cell adhesion.
During cell signaling, the proteoglycans and glycoproteins act as receptors for chemical messengers and activate the intracellular signaling cascade.
In humans, the glycocalyx has specific roles in certain cell types. For instance, in blood vessels, it protects the endothelial cell lining from the shear stress of the blood flow.

glycocalyx and its functions

Glycocalyx and its Functions

The glycocalyx is a carbohydrate-rich, fuzzy-appearing layer on the outer surface of the cell membrane. It is highly hydrophilic, because of this it attracts large amounts of water to the cell&#39;s surface. This aids the cell&#39;s interaction with the watery environment and also helps it to obtain substances dissolved in the water. It is also important for cell identification, self/non-self determination, and embryonic development and is used in cell-to-cell attachments to form tissues.
Components of Glycocalyx
The glycocalyx is composed of glycoproteins, proteoglycans, glycolipids, and other soluble plasma components. A glycoprotein is a protein with carbohydrate molecules attached, which extend into the extracellular matrix as part of the glycocalyx. The attached carbohydrate molecules aid in cell recognition. Proteoglycans are generally considered the glycocalyx&#39;s backbone, consisting of a core protein with glycosaminoglycan chain linkages. There are five types of glycosaminoglycan chains: heparan sulfate, chondroitin sulfate, dermatan sulfate, keratan sulfate, and hyaluronan. The glycolipids are lipids with covalently attached sugar molecules. Soluble components of glycocalyx include various types of proteins and soluble proteoglycans. For example, albumin and orosomucoid are some soluble components derived from the bloodstream or endothelium and play a pivotal role in preserving the charge and selectivity of the barrier.
Glycocalyx and Immune System
The glycocalyx can have various roles. For example, it may have molecules that allow the cell to bind to another cell, it may contain receptors for hormones, or it might have enzymes to break down nutrients. The type of glycocalyx&#160; found in a person&#39;s body is a product of that person&#39;s genetic makeup. It&#160; gives each of the individual&#39;s trillions of cells the &#34;identity&#34;&#160;of belonging in the person&#39;s body. This identity is the primary way that a person&#39;s immune defense cells &#34;know&#34;&#160;not to attack the person&#39;s own body cells, but it also is the reason organs donated by another person might be rejected.
A section of this text is adapted from <a href="https://openstax.org/books/anatomy-and-physiology-2e/pages/3-1-the-cell-membrane">Openstax, Anatomy and Physiology 2e, Section 3.1</a>
A section of this&#160; text is adapted from <a href="https://openstax.org/books/biology-2e/pages/5-1-components-and-structure">Openstax, Biology 2e, Section </a><a href="https://openstax.org/books/biology-2e/pages/5-1-components-and-structure">5.1</a>

The glycocalyx is a carbohydrate-rich, fuzzy-appearing layer on the outer surface of the cell membrane. It is highly hydrophilic, because of this it ...

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Anatomy and Physiology

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Cell Membrane Structure and Functions

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glycocalyx in cell recognition

The glycocalyx is a carbohydrate-rich layer on the outside of the cell membrane. It has a fuzzy appearance and is highly hydrophilic, which means it attracts water. That helps the cell interact with its watery environment and helps it obtain substances dissolved in that water.

The glycocalyx is also important for how cells identify one another. It supports self and non-self recognition, and it helps in embryonic development. Cells also use it for cell-to-cell attachment, which helps tissues form and stay organized.

The glycocalyx is made of glycoproteins, proteoglycans, glycolipids, and other soluble plasma components. A glycoprotein is a protein with carbohydrate molecules attached, and those sugars extend into the extracellular matrix as part of the glycocalyx. The attached carbohydrate molecules help with cell recognition.

Proteoglycans are usually considered the backbone of the glycocalyx. They contain a core protein with glycosaminoglycan chain linkages. The five glycosaminoglycan chains are heparan sulfate, chondroitin sulfate, dermatan sulfate, keratan sulfate, and hyaluronan. Glycolipids are lipids with covalently attached sugar molecules.

Soluble components of the glycocalyx include different proteins and soluble proteoglycans. Albumin and orosomucoid are two examples. These components come from the bloodstream or the endothelium, and they help preserve the charge and selectivity of the barrier.

The glycocalyx can also carry molecules that let a cell bind to another cell. It may contain receptors for hormones, or enzymes that break down nutrients. The exact glycocalyx in a person’s body comes from that person’s genetic makeup. It gives each cell an identity that marks it as part of the body. That identity helps immune defense cells avoid attacking the body’s own cells, and it also helps explain why donated organs from another person may be rejected.

Glycocalyx in Cell Recognition

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The glycocalyx is a carbohydrate-rich layer on the outside of the cell membrane. It has a fuzzy appearance and is highly hydrophilic, which means it attracts water. That helps the cell interact with its watery environment and helps it obtain substances dissolved in that water. The glycocalyx is also important for how cells identify one another. It supports self and non-self recognition, and it helps in embryonic development. Cells also use it for cell-to-cell attachment, which helps tissues...

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key terms and concepts

Learn how the glycocalyx helps cells recognize each other, attract water, form tissues, and avoid immune attack in high school biology.

Glycocalyx in Cell Recognition | JoVE K12

anatomy and physiology

JoVE Core Anatomy and Physiology showcases the anatomical and physiological details of the human body in comprehensive, clear, and engaging video animations. This collection of lessons focuses on the structures, components, functions, and requirements of the human body. It is complemented by scientist-in-action videos that demonstrate the application of this knowledge in real-world medical and research settings.

Glycocalyx in Cell Recognition

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