Micro 297 Graduate Immunology Lecture 15 Development of B Lymphocytes I Generation of Antibody Diversity Thursday August 14, 2003 Michael Wolcott READING Chapter 7. Overview of B-Cell Development. Generation of Lymphocyte Antigen Receptor.
Micro 297 Graduate ImmunologyLecture 15Development of B Lymphocytes IGeneration of Antibody DiversityThursday August 14, 2003Michael WolcottREADING Chapter 7
Any model must accommodate known properties of Ig’s
Two genes – one polypeptide chain
Ig genes are rearranged in B cells
Recombination Signal Sequences – RSS – ensure that DNA rearrangements take place at the correct location relative to the V, D, or J gene segment
The complex of enzymes that act in concert to effect somatic V(D)J recombination is termed the V(D)J recombinase
Recombination of gene segments that are in the opposite orient-ation results in inver-sion and integration of the intervening DNALight Chain Recombination Can Occur By Either “looping out” or “Inversion”
Which mechanism utilized depends on the orientation of the V and J segments.
So how would you prove it?
Diversity with in the Ig repertoire is achieved by several means.
Both forms are derived from the same H-chain gene sequence
Somatic hypermutation further diversifies the Ab repertoire