Inhoudsopgave
Welke celtypen kunnen antigenen presenteren?
De belangrijkste immuuncellen die antigenen kunnen presenteren zijn dendritische cellen en macrofagen. Wanneer deze cellen een virus of bacterie hebben gefagocyteerd, zullen ze kleine moleculen die afkomstig zijn van de pathogeen naar hun membraan sturen, waar ze door MHC-eiwitten worden gebonden.
Wat zijn B en T cellen?
T-lymfocyten worden alleen gebruikt bij bestrijding van virussen, ze binden zich aan een geïnfecteerde cel zodat die dood gaat. B-cellen maken antistoffen die koppelen aan de ziekteverwekker. Bij virussen zorgen de antistoffen ervoor dat ze geen cellen meer binnen kunnen gaan.
What is the clonal selection theory of lymphocytes?
Clonal selection. Clonal selection Theory of lymphocytes: 1) A hematopoietic stem cell undergoes differentiation and genetic rearrangement to produce 2) immature lymphocytes with many different antigen receptors.
What is clonal selection?
Clonal selection is part of the primary immune response. A primary immune response is provoked when a new antigen invades the body. Traveling through the circulatory system, the antigen will inevitably meet up with the lymphocyte that has the correct antibody pattern. When the lymphocyte and antigen connect, a chemical change is triggered.
How are B cells selected for clonal selection?
In clonal selection, an antigen is presented to many circulating naive B cells and (via MHC) T cells, and the lymphocytes that match the antigen are selected to form both memory and effector clones of themselves.
Why are lymphocytes selected during antigen presentation?
Clonal selection assumes that lymphocytes are selected during antigen presentation because they already have receptors for that antigen. In clonal selection, an antigen is presented to many circulating naive B cells and (via MHC) T cells, and the lymphocytes that match the antigen are selected to form both memory and effector clones of themselves.