Question

How does activation by T-independent antigens differ from this figure?

Extracellular antigens B cell receptors Antigen fragments MHC class II with antigen displayed on surface **Cytokines Plasma cell Antibodies T cell B cell B cell 1 APC receptors 2 Antigen is 3 Antigen fragments are T helper cell recognize and phagocytized and displayed on the B cell secretes cytokines, attach to antigen. digested (see surface, attracting a activating a B cell. Figure 17.12). matching T helper cell. Figure 17.5 Activation of B cells to produce antibodies. In this illustration, the B cell is producing antibodies against a T-dependent antigen. Q How does activation by T-independent antigens differ from this figure? 5 The activated B cell begins clonal expansion, producing an army of antibody-producing plasma cells and memory cells (not shown).

Answer 1

T-Independent antigens induce the antibody production by B lymphocytes without the involvement of T lymphocyte. As you can in the below-mentioned figure, there are involvement of IgM production from lymphocytes.

T cell-independent B cell activation B cell polysaccharide antigen with repeating epitopes IgM pathogenic bacterial cell activation of B cell and secretion of pentameric IgM

However, in case of T-dependent antigens, took the help of T helper cell to represent and release of antibodies from B cell.