On Tue, 9 Dec 1997, Andrew Louka wrote:
> Why one B cell, one specificity? Why not have multiple specificities per
> B cell - surely this would have been more effective (and energy efficient!).
Nope. Then you'd have B cells with two or more specific surface
immunologlobins. Since the B cell couldn't distinquish which one it got
activated through, it would presumably behave as if all of its receptor
specificities had been activated. It would await T cell help,
proliferate, and differentiate into plasma cells. Of course, it would now
be spending the metabloic energy to produce two or more specific secreted
antibodies.
Of course, the odds that the appropriate antigens are present for more
than one of the antibodies is low, and so the extra production is waste.
John Seavitt
P.S. The current setup also allows the use of allelic exclusion to select
functional rearrangements in BCR genes, which would no longer be a
possible strategy for a multispecificty B cell.
