Sections to Skip for Ch 2
Figure 2.3 - Enzyme digestion of Ab’s
Monoclonal Antibodies Fig 2.12 & 2.13
Examples of Problematic Ab binding to various
Penicillin - antibiotic that IgE can bind to and initiate inflammatory
DNA - Systemic Lupus Erythematosus (Lupus)
Lysozyme - Hen egg component
Questions From Class
Is IgM only pentameric?
IgM is made as a monomer in the cell and then assembled in
the cell into a pentamer, with the help of the J chain. After
assembly, it is secreted from the cell as a pentamer.
Therefore, the secreted form of IgM is only present as a
Why does a T helper cell (CD4 TH1 have to activate a
macrophage after the same macrophage has already
phagocytosed a pathogen?
Macrophages have two main effector functions (see Fig
1.14): 1) phagocytosis and 2) effector signaling by secretion
of cytokines. TH1 cells will themselves secrete cytokines to
increase the overall effector activity of the macrophage
including the secretion of cytokines from the same
macrophage (Fig 1.27, 3.11 and 8.15).
Questions From Class (continued)
What does soma mean with respect to somatic
Soma refers to all the cells of the body (soma is latin for
body) except germ cells. Germline configuration refers to the
arrangement of genes in all of the somatic cells and germ
cells that do not undergo somatic recombination. In cells that
have the unique capability to undergo somatic recombination,
such as B and T cells, germline configuration refers to gene
arrangement before those cells have undergone gene
rearrangement (by the process of somatic recombination)
A) Can the two types of light chain( and ) be made at the
same time in the same B cell? B) How does that affect Ab
A) No. One B cell only expresses one type of light chain. B)
Please see the following slide for the correct calculation.
Random Recombination of
Gene segments is one
factor contributing to
(200* + 120*)
10,530 = 3,369,600 Ig molecules
* Only one light chain loci gives rise to one functional polypeptide!