Solved B Cell Development Ii Clonal Selection Clonal Expansion Figure 13.1e. 1 13.1 e. 1: clonal selection, step 1. during its development, each b lymphocyte becomes genetically programmed, through a process called gene translocation, to make a unique b cell receptor. molecules of that b cell receptor are placed on its surface where it can react with epitopes of an antigen. Terms in this set (6) step 1. clonal selection and antigen binding. step 2. antigen processing and presentation. step 3. b cell t helper cell cooperation and recognition. step 4. b cell activation.
Solved B Cell Development Ii Clonal Selection Clonal Expansion Clonal selection is a theory stating that b cells express antigen specific receptors before antigens are ever encountered in the body. after b cell activation, the b cells clone themselves through clonal expansion, but during each cellular division, random mutations occur that gradually increase the binding affinity for b cell produced. Clonal selection of b cells. clonal selection and expansion work much the same way in b cells as in t cells. only b cells with appropriate antigen specificity are selected for and expanded (figure 21.23). eventually, the plasma cells secrete antibodies with antigenic specificity identical to those that were on the surfaces of the selected b cells. The “clonal selection hypothesis” evolved largely as a means to account for “the absence of immunological response to self constituents and the related phenomena of immunological tolerance” (burnet 1957). thus, the presence of a cell surface molecule that reflected the unique specificity of each cell provided a convenient means, not only for selective antigenic stimulation, but also. Abstract. clones are the fundamental building blocks of immune repertoires. the number of different clones relates to the diversity of the repertoire, whereas their size and sequence diversity are linked to selective pressures. selective pressures act both between clones and within different sequence variants of a clone.
Clonal Selection Of B Cells Stock Illustration Download Image Now The “clonal selection hypothesis” evolved largely as a means to account for “the absence of immunological response to self constituents and the related phenomena of immunological tolerance” (burnet 1957). thus, the presence of a cell surface molecule that reflected the unique specificity of each cell provided a convenient means, not only for selective antigenic stimulation, but also. Abstract. clones are the fundamental building blocks of immune repertoires. the number of different clones relates to the diversity of the repertoire, whereas their size and sequence diversity are linked to selective pressures. selective pressures act both between clones and within different sequence variants of a clone. 5. clonal selection and clonal expansion. as mentioned above, during early differentiation of naive b lymphocytes in the bone marrow, each b lymphocyte becomes genetically programmed to make an antibody with a unique antigen binding site (fab ) through a series of gene translocations, and molecules of that antibody are put on its surface to function as the b cell receptor . 00:09:06;18 and this holds true both for t cells and for b cells. 00:09:11;09 when the clonal selection hypothesis was put forward, we didn't know what the immune cells 00:09:18;03 for adaptive immunity were. 00:09:20;20 at this time in 1957, we thought these were just macrophages, or some macrophage like cell.
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