University:
York University
Course:
SC/BIOL 3120 | Immunobiology
Academic year:

2023
Views:

428

Pages:

2
Author:

Niklas

#HEV's express cellular adhesion molecules HEV's in the lymph nodes always have carbohydrate ligands expressect selectins glycoproteins that have an exhacellular lectin-like domain protein that binds a carcelydrals expressed on T-cell General structure of CAM familles Maine Call -different types L-selectins (CDULL) E-selectins (COUZE) P-selectins (CDUZP) Carbohydrate donate chain -bind to carbohydrate groups that decorate glycosylated mucin-like proteins →hnown as peripheral node addressins (PNAds) same thing →mucin-like proteins a group of heanity glycosylated serine and threonine rich proteins that bind to selectins Selectins Igsuperfamily CM in english two sticky molecules that bind to each other mucin-like protein nas carbohydrate chains -sticky carbohydrates bind to sticky selectins T-cell expresses integrins -Integrins hetero dimeric proteins consisting of nen covalently associated & and B chains which bind extracellular matris molecules and cell surface adhesion molecules → and domains are bent over in a jackknife position when INACTIVE and Stand up when ACTIVE -activated by inside-out signaling allows cells to probe other cell surfaces before making a full commitment to an interaction -iculocytes express several important integrins Bs integrins (CD1B) bind to members of the 19 super family Cellular adhesion molecules (ICAMS) integrins are on the surface of the cell →the cell also has receptors for chemokines chemokine binds to chemokine receptor causes inside-out signaling causes intermediate offinity and integrin straightens out integrin binding to carbohydrate causes higher affinity sigruilling C High affinity signaling#HEV's express chemokines/chemokine ligands *the T-cell expresses chemokine receptor cause molecules to come high concentration to low Chemokines (and chemokine receptors): small poly peptides that regulate immune cell trafficting -act as chemo attractants and play a role in adhesion/activation of leukocytes -inflammatory chemokines produced in response to infection and pro inflammatory cytokines example: 11-3 (aka CACLI) is the most common inflammatory chemokine, made by multiple cells in response to pathogen invasion Rreceptor different cells are going to have different combos L= ligand the chemokine itself of chemokine receptors do not have to know all receptors BUT know nomenclature Immunoglobin Superfamily CAMS (ICAMS): a diverse group of proteins that act as ligands for Bs integrins exhibit hemolysic binding they interact with themselves -helps direct cell entry into the mucosa once in the lymph node, how do cells contact each other? 1) chemokines antigen presenting cells 2) Fibroblastic Reticular Gell (FRC) Network: a network of stromal cells that provide a sooduny for APC's and T-cells be of close proximity, each DC can surrey up to 5000 T-cells each hour If the naive T-cell doesn't find its cognate antigen, it upregulates the sphingosine-1-phosphate receptor (31PRI) efferent lymphatic vessels express a lot of SIP allows the lymphocyte to overcome the affinity for the chemokine and thus leave the lymph node! Antigen Arrival at the Lymph Node T-cells and B-cells figure is meant to distinguish between how antigen is delivered to T. and B-cells pay attention to intermation boar