- Nitric oxide production by human intestinal epithelial cells and competition for arginine as potential determinants of host defense against the lumen-dwelling pathogen Giardia lamblia. Eckmann, L., Laurent, F., Langford, T.D., Hetsko, M.L., Smith, J.R., Kagnoff, M.F., Gillin, F.D. J. Immunol. (2000)