clonal selection theory

n.
  1. The theory that the mutation of stem cells produces all possible templates for antibody production and that exposure to a specific antigen selectively stimulates the proliferation of the cell with the appropriate template to form a clone or colony of specific antibody-forming cells.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.