Key points are not available for this paper at this time.
Using recombinant DNA techniques, we reconstructed a genealogical tree (Sablitzky, F., Wildner, G. & Rajewsky, K. (1985) EMBO J. 4, 345-350) that connects three clonally related B cells producing somatically mutated antibodies to a progenitor cell expressing a germ line-encoded antibody. The somatic mutants had been isolated from an in vivo immune response. The germ line-encoded progenitor antibody bound the antigen with high affinity. Intraclonal affinity maturation occurred stepwise over a 15-fold range.
Kocks et al. (Tue,) studied this question.