The proportion of B-cell subsets expressing kappa and lambda light chains changes following antigenic selection.

Using a mixture of 'top-down' theory and 'bottom-up' extrapolation from experimental observation, Rodney Langman and Melvin Cohn discuss some of the conflicting points of view regarding the ratio of kappa (kappa)- to lambda (lambda)-expressing B cells. Despite the somewhat arcane nature of the subject, the authors make a strong general case for the use of computer simulations as a means of reconciling top-down generalizations with quantitative bottom-up extrapolations. With the appearance of two recent papers, the authors show how the top-down theory prevailed in a resolution of the controversy.