1. Development of B lymphocytes
Parham, Chapter 4
H. HogenEsch, 2004

2. B cell development
Fig. 4.2
H. HogenEsch, 2004

3. IgM IgG IgE IgA antigen-independent pre-B cell immature B cell
stem cell ( m
chain +)
(IgM +)
(IgM +
, IgD +)
antigen-dependent
IgM
isotype switching
IgG
IgE
IgA
H. HogenEsch, 2004

4. Pre-B cell pre-B cell receptor = m + surrogate light chain
H. HogenEsch, 2004

5. B cell development in bone marrow
H. HogenEsch, 2004
Bone marrow stromal cells

6. Ig gene rearrangements – allelic exclusion
H. HogenEsch, 2004
Fig. 4.6

7. Sequential L chain gene segment rearrangements
H. HogenEsch, 2004

8. Immunoglobulin gene expression during B cell development
H. HogenEsch, 2004

9. Selection of immature B cells
Fig. 4.13
H. HogenEsch, 2004

10. Receptor editing
H. HogenEsch, 2004

11. B-1 cells vs. B-2 cells
H. HogenEsch, 2004

12. B-1 cells vs. B-2 cells (cont’d)
H. HogenEsch, 2004

13. X-linked agammaglobulinemia
Recurrent infections of extracellular bacteria
Recessive, X-linked
Defect in Bruton’s tyrosine kinase
Nearly complete absence of circulating immunoglobulins
Reduced number of pre-B cells in bone marrow, lack of mature B cells
Normal thymus and normal number of T cells
H. HogenEsch, 2004

14. Circulation of naïve B cells
Fig. 4.15
H. HogenEsch, 2004

15. Further development of mature B cells
H. HogenEsch, 2004

16. Effect of specific antigen on B cell migration and differentiation
Fig. 4.16
H. HogenEsch, 2004

17. Histology of the lymph node cortex
M = mantle zone
GC = germinal center
D = dark zone
L = light zone
H. HogenEsch, 2004

18. B cell life cycle days - weeks Naïve B cell apoptosis Ag 5 days IgM
paracortex
medulla
months
bone marrow
IgG
germinal
center
isotype switching
memory
B cell
H. HogenEsch, 2004

19. B cell tumors
H. HogenEsch, 2004

20. Burkitt’s lymphoma
H. HogenEsch, 2004