Abstract
Production of high-affinity, long-lived, circulating antibodies to vaccines or infectious agents or their products requires collaboration between two kinds of lymphocytes: antigen-specific helper T lymphocytes and antigen-specific B lymphocytes. The T cells provide the signals that the B cells need to proliferate and differentiate into clones of antibody-secreting plasma cells, and memory B cells. During birth in the bone marrow, each B cell assembles a gene encoding a unique antibody molecule, which it puts on the cell surface as a receptor for antigen. Antigen binding to the receptor on those rare B cells that are specific for it delivers activating signals to the B cell, but these signals are typically insufficient for an antibody response. The surface receptor also enables the antigen-specific B cell to internalize the antigen, process it, and present it back on the cell surface as a small peptide bound to an MHC class II molecule as a target for the helper T cell. When the helper T cell recognizes antigen presented by the B cell, it delivers help to the B cell in the form of secreted cytokines and an essential membrane-bound cytokine in TNF family called CD40 ligand (CD40L or CD154).
Original language | English (US) |
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Title of host publication | Activation of the Immune System |
Publisher | Elsevier Inc. |
Pages | 175-178 |
Number of pages | 4 |
Volume | 3 |
ISBN (Print) | 9780080921525 |
DOIs | |
State | Published - Apr 27 2016 |
Keywords
- Antibody response
- Antigen presentation
- B cell activation
- CD40
- CD40L
- Germinal center
- MHC class II
- T cell help
- Tfh
ASJC Scopus subject areas
- General Medicine