title: Notice of Concern.
abstract: The editors of The FASEB Journal have been informed by Bente Klarlund Pedersen, MD, DMSc, Professor of Integrative Medicine, Director of Centre of Inflammation and Metabolism, Department of Infectious Diseases and CMRC Rigshospitalet at the University of Copenhagen Faculty of Health Sciences, Copenhagen, Denmark, of an ongoing investigation into the validity of the data contained in an article published in The FASEB Journal in 2003, which is part of a larger investigation involving other articles appearing in other journals. We await a final report from the investigating institution to learn the outcome of this investigation. The article is: Penkowa, M., Keller, C., Keller, P., Jauffred, S., and Pedersen, B. K. (2003) Immunohistochemical detection of interleukin-6 in human skeletal muscle fibers following exercise.