Related Experiment Videos

Isolation and characterization of lymphokine cDNA clones encoding mouse and human IgA-enhancing factor and eosinophil

T Yokota1, R L Coffman, H Hagiwara

  • 1Department of Molecular Biology, DNAX Research Institute of Molecular and Cellular Biology, Palo Alto, CA 94034-1104.

Conditioned medium from the Con A-treated mouse helper T-cell clone Ly1+2-/9 contains activities that enhance the production of IgA by mouse B cells and induce human cord blood cells to form eosinophil colonies. We have isolated a cDNA sequence that expresses IgA-enhancing factor and eosinophil colony-stimulating factor activities from a cDNA library prepared from activated Ly1+2-/9 cells. Based on homology with the mouse cDNA sequence, a human cDNA sequence coding for an interleukin with IgA-enhancing factor and eosinophil colony-stimulating factor activities was isolated from a cDNA library prepared from a human T-cell clone stimulated with anti-T3 antibody and phorbol 12-myristate 13-acetate. DNA sequence analyses revealed that mouse and human cDNA clones encode proteins of 133 and 134 amino acids, respectively, that are identical to cDNA clones encoding the T-cell replacing factor I and B-cell growth factor II activities. These results establish that a single cDNA clone encodes a protein that acts as a growth and differentiation factor for both B cells and eosinophils.

Related Concept Videos