The glycocalyx (or felting or concealment coat) is a layer of polyholosides present on membrane surface external of the animal cell S like on the wall external of some bacterium S. In some epithelium S, the thickness of this layer can reach 0.5 µm and is definitely visible with the optical microscope after coloring.

Functions

Its principal function is to help with the intercellular recognition. Indeed, several of the sugars exposed to cellular surface belong to the system major Complexe of histocompatibility (CMH or HLA).

The glycocalyx, at the cells of mammals, allows the identification of the cell, and thus makes it possible the body to distribute the molecules specific to this cellulaire.< type! --this last sentence is obscure for me-->

The glycocalyx is often used by the viruses as access road to the cell. Moreover it is a dynamic barrier with adhesion in the sense that he is opposed to the fast approach of two cellular membranes, a reduction in the glycocalix showed an increase in adhesive activity.

He also plays a part against the mechanical, chemical and enzymatic aggressions.

Composition

The glycocalyx is composed of Glycoprotéine S and Glycolipide S.

Role in pathology

The polyholosidic molecules are negatively charged and make it possible a cell to adhere to a wall: these factors of adhesion play a part in the invasive capacity of the bacteria. Some glycocalyx are larger and proteinic ( fimbiae or pili common) allowing the connection of the bacteria on the cells (Escherichia coli of certain infections urinary).

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Ier front century J. - C. | Troche | Génolhac | Joseph Khoury | Handbook (televised series)