What is MECA 79?
What is MECA 79?
MECA-79 recognizes a carbohydrate epitope shared with a group of sulfation decorated sialomucins, including sulfated ligands for CD62L (CD34, GlyCAM-1, Sgp200, and a subset of MAdCAM-1). MECA-79 is expressed on high endothelial venules (HEV) of lymphoid tissues, chronic inflamed tissues and rheumatoid synovia.
What are the HEV and what is their function?
High endothelial venules (HEVs) and lymphatic vessels (LVs) are essential for the function of the immune system, by providing communication between the body and lymph nodes (LNs), specialized sites of antigen presentation and recognition.
What is peripheral node addressin?
Peripheral node addressin (PNAD) is an endothelial cell carbohydrate epitope expressed predominantly in peripheral lymph nodes and controls the homing of lymphocytes via binding of L-selectin.
Why spleen is called secondary lymphoid organ?
Secondary lymphoid organs: These organs include the lymph nodes, the spleen, the tonsils and certain tissue in various mucous membrane layers in the body (for instance in the bowel). It is in these organs where the cells of the immune system do their actual job of fighting off germs and foreign substances.
What is peripheral node?
Abstract. Peripheral node addressin (PNAd) marks high endothelial venules (HEV), which are crucial for the recruitment of lymphocytes into lymphoid organs in non-mucosal tissue sites. PNAd is a sulfated and fucosylated glycoprotein recognized by the prototypic monoclonal antibody, MECA-79.
Do B cells have L-selectin?
L-selectin has also been leveraged to identify activated B cells with different cell fate outcomes, with loss of L-selectin distinguishing activated B cells destined to differentiate to antibody-secreting cells.
Is L-selectin a receptor?
In naive lymphocytes, L-selectin functions as a homing receptor, directing the cells to the HEVs of the peripheral lymph nodes. Here, L-selectin interacts with the vascular addressin GlyCAM-1 (which is expressed only on the surfaces of the HEVs) and induces the lymphocytes to extravasate into the lymph nodes.
Is malt a secondary lymphoid organ?
Secondary lymphoid organs (including the spleen, lymph nodes, and MALT)…Key terms.
| Term | Meaning |
|---|---|
| Spleen | Secondary lymphoid organ that filters blood and stores erythrocytes and lymphocytes |
| Lymph nodes | Secondary lymphoid organ that filters lymph |
| MALT | Mucosa-associated lymphoid tissue, a type of secondary lymphoid organ |
What is the difference between primary and secondary lymphoid centers in the human body?
Primary lymphoid organs allow lymphoid stem cells to proliferate, differentiate, and mature while secondary lymphoid organs encourage functional lymphoid cells to grow. In addition, primary lymphoid organs contain only T cells or B cells, while secondary lymphoid organs contain T cells and B cells , respectively.