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A new, simple method for the preparation of lymphocytes bearing specific receptors

Purification of antigen‐specific spleen cells using solid phase immunoadsorbents has two main difficulties: (1) unspecific binding of lymphoid cells to the adsorbent and (2) detachment of cells bound to the adsorbent without affecting cell viability and function. Both difficulties have been overcome by using gelatin as a matrix for cellular immunoadsorbtion. Mouse spleen cells were fractionated at 4 °C in rotating tubes coated with a thin layer of 2,4‐dinitrophenyl (DNP)‐gelatin or FGG (fowl IgG)‐gelatin. Bound cells could be recovered by melting the gel matrix at 37 °C without affecting cell viability. The specificity of the binding of a small subpopulation of spleen cells to the adsorbent has been shown by: (1.) inhibition of the binding with free antigen, (2.) depletion of DNP‐gelatin binding cells by serial fractionation, (3.) a specific increase of binding cells in spleen cell populations from immunized mice; and (4.) a 30‐fold enrichment in the binding cell population, of antigen‐binding cells as determined in an indirect antigen‐binding assay. The capacity of cell populations enriched in specific antigen‐binding cells, to respond to a T‐independent antigen DNP‐polymerized flagellin, was tested in an adoptive‐transfer system. No evidence could be obtained of an enrichment of DNP‐specific antibody‐forming cell precursors in populations of normal spleen cells that had been enriched for antigen‐binding cells.