What are thymus-dependent antigens?
Thymus-dependent antigens include proteins, polypeptides, hapten-carrier complexes, erythrocytes, and many other antigens that have diverse epitopes. T dependent antigens contain some epitopes that T cells recognize and others that B cells identify.
Which of the following cells are thymus-dependent?
Antigens that require the help of T cells for B cell activation are thymus-dependent (T-dependent) antigens. Antigens that can stimulate B cells without the help of T cells are thymus- independent (T-independent) antigens.
What is a thymus-dependent antigen and how does it differ from an thymus independent antigen?
In this model, it has been conceived that T-independent antigens can stimulate B cells directly via multivalent binding to the cell surface by a “matrix” of repeating antigenic determinants, whereas in the case of T-dependent antigens, such multivalent binding would occur in association with a specific T cell product ( …
What is the first cell that recognizes a thymus-dependent antigen?
B-cell
B-cell activation by a thymus-dependent antigen comprises a sequence of events. An antigen crosslinks mIg, generating signal 1, which leads to increased expression of class II MHC and costimulatory B7. Antigen–mIg complexes are internalized by receptor-mediated endocytosis and degraded to peptides.
What is TD AG?
T Dependent Antigen (Td-Ag) These are thymus-dependent or simply T-dependent (TD) responses. B cell activation by T-dependent antigens requires contact-dependent help delivered by the interaction between CD40 on B cells and CD40L on activated TH cells.
What is thymus-dependent lymphocytes?
Thymus-dependent lymphocytes display a restricted range of specificity when compared to thymus-independent (B) lymphocytes. Recent work indicates that individual T lymphocytes possess receptors that interact with both thymus-dependent antigens and MHC gene products, either independently or as associated structures.
How are T-dependent antigens different from T-independent antigens quizlet?
How do T-independent antigens differ from T-dependent antigens? T-independent antigens (lipopolysaccharide and polysaccharides that have numerous identical epitopes) can activate B cells in the absence of T-cell assistance, while T-dependent antigens (proteins) require this T-cell assistance).
How does TD AG differ from TI AG?
Carrier peptide-specific T cells (mainly follicular helper T Cell), recognize the MHC-II peptide antigen by its T Cell Receptor (TCR)….Difference between T dependent Antigen and T independent Antigen.
| T dependent (TD) Antigen | T independent Antigen |
|---|---|
| Activate mature B cells only | Activate both mature and immature B cells |
What is T dependent antigen?
An antigen that requires the presence of T cell help to stimulate the B cell to secrete antibody. Such antigens do not elicit a productive antibody response by B cells unless the B cell receives help from a CD4 T cell.
What is the difference between T dependent and T-independent antigens?
T-dependent antigens can stimulate B cells to become activated but require cytokine assistance delivered by helper T cells. T-independent antigens can stimulate B cells to become activated and secrete antibodies without assistance from helper T cells.