Cell Separation on Affinity Columns: The Immunospecific Precursor Cells from Unil (lactoside hapten/lymphocyte receptors/immunology)

We have used affinity columns to isolate from the spleens of unimmunized mice a population of lymphocytes that specifically bind a lactoside hapten. These cells are able to initiate an antibody response to azoplhenyl-f-lactoside when transferred to appropriate irradiated recipients. Considerable evidence supports a clonal selection theory of antibody formation (1). It is generally believed that normal, unrimmunized vertebrates contain many diverse populations of lymphocytes that exhibit antibody-like receptors on their surfaces and that a given antigen stimulates only selected pre- cursor cells to proliferate and to give rise to antibody-pro- ducing cells of corresponding specificity. For secondary lym- phoid tissues, estimates of the frequency of precursor cells specific for a multideterminant antigen (e.g., foreign eryth- rocytes or polymeric flagellin) are in the range of 5 X 10-4 to 10-5 (2). To investigate cellular differentiation in the im-