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First a review…. Adopt as a perspective that: One B-cell produces one antibody Make that perspective more exacting: One B-cell produces one idiotype . Cassettes (V, J, [D],) ( aka gene segments ) “fuse” ( to make an idiotype ).
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First a review… Adopt as a perspective that: One B-cell produces one antibody Make that perspective more exacting: One B-cell produces one idiotype. Cassettes (V, J, [D],) (aka gene segments) “fuse” (to make an idiotype). Fusing occurs because RAG recognizes one turn/two turn signals on cassettes. CDR3 develops through junctional flexibility (trimming) and addition of P & N nucleotides (expanding). CDR1 and CDR2 (especially) and CDR3 become more varied because of somatic hypermutation.
First a review… now with images And, I will use images from a different source. Remember to be critical of what “interpretative” drawings convey…
First a review… still with images RAG: what does it do? …how does it work?
First a review… still with more images RAG: what does it do? …how does it work? …what about P&N nucleotides?
PART IV (some new stuff) • How do immunoglobulins assemble? • Some immunoglobulins are in the surface membrane of immature B-cells while other immunoglobulins of the same idiotype are secreted by mature B-cells. What’s the difference? • Similarly, identical variable regions can be shared among different isotypes. How? • B-cells are diploids with two sets of genetic instructions. How does just one set get expressed?
Some immunoglobulins are in the surface membrane of immature B-cells while other immunoglobulins of the same idiotype are secreted by mature B-cells. What’s the difference?
Similarly, identical variable regions can be shared among different isotypes. How?
B-cells are diploids with two sets of genetic instructions. How does just one set get expressed?
The general scheme of B-cell development • STEM CELL • pro (genitor) Bcell • pre Bcell • Ag-selected ( stimulated)- Bcell • Ab secreting plasma cell