- Digitoxin mimics gene therapy with CFTR and suppresses hypersecretion of IL-8 from cystic fibrosis lung epithelial cells. Srivastava, M., Eidelman, O., Zhang, J., Paweletz, C., Caohuy, H., Yang, Q., Jacobson, K.A., Heldman, E., Huang, W., Jozwik, C., Pollard, B.S., Pollard, H.B. Proc. Natl. Acad. Sci. U.S.A. (2004)