CHAPTER 4 – ANTIGEN RECOGNITION IN THE ADAPTIVE IMMUNE SYSTEM
(FROM THE TEXT)
1. In the adaptive immune system, the molecules responsible for specific recognition of
antigens are antibodies and T cell antigen receptors.
2. Antibodies (AKA Immunoglobulins) may be produced as membrane receptors of B
lymphocytes and as proteins secreted by antigen stimulated B cells that have
differentiated into antibody-secreting cells. Secreted antibodies are the effector
molecules of humoral immunity, capable of neutralizing microbes and microbial toxins.
3. TCRs are membrane receptors and are not secreted.
4. The core structure of an antibody consists of two heavy chain and two light chains
forming a disulfide-linked complex. Each chain contains variable region that recognizes
antigen and a constant region that provides structural stability. Heavy chains also
perform effector functions in antibodies.
5. TCRs consist of an α chain and a β chain. Each chain contains one V region and one
constant region. Both chains participate in antigen recognition.
6. The genes that encode antigen receptors consist of multiple segments th