College 21 mei

The Development of B lymphocytes
Chapter 6 Parham
Hans de Haard
21th of May 2010

Agenda
• Stages in development of B cells
• B cell development in bone marrow
• Heavy chain rearrangement
• Light chain rearrangement more efficient process
• Checkpoints
• B1 versus B2 lymphocytes
• Removal self reactivity
• B cell development in secondary lymphoid tissues
• Differentiation into mature B lymphocytes
• Maturation into plasma cells and memory cells
• Various B cell tumors represent different stages in B cell development

Agenda
• Stages in development of B cells
• B cell development in bone marrow
• Heavy chain rearrangement
• Light chain rearrangement more efficient process
• Checkpoints
• B1 versus B2 lymphocytes
• Removal self reactivity
• B cell development in secondary lymphoid tissues
• Differentiation into mature B lymphocytes
• Maturation into plasma cells and memory cells
• Various B cell tumors represent different stages in B cell development

Stages in development B cells
• Phase 1: B cell precursors in bone marrow acquire
functional antigen receptors via gene rearrangements
• Phase 2: elimination anti-self (tolerance) in bone
marrow and 2nd lymphoid tissues
• Phase 3: positive selection for B cells expression of
pathogen specific Ig in 2nd lymphoid tissues
• Phase 4: mature B cells circulate via lymph and blood
to lymphoid tissues patrolling for infections
• Phase 5: proliferation and clonal expansion pathogen
specific B-cells in 2nd lymphoid tissues
• Phase 6: maturation into:
• plasma cells =>remain in 2nd lymphoid tissues, express large quantities
pathogen specific Ab
• memory B cells (circulate) for rapid Ab generation in case of future
infections with same pathogen

Agenda
• Stages in development of B cells
• B cell development in bone marrow
• Heavy chain rearrangement
• Light chain rearrangement more efficient process
• Checkpoints
• B1 versus B2 lymphocytes
• Removal self reactivity
• B cell development in secondary lymphoid tissues
• Differentiation into mature B lymphocytes
• Maturation into plasma cells and memory cells
• Various B cell tumors represent different stages in B cell development