From the Department of Otolaryngology—Head and Neck Surgery (Drs. Rothbaum, Francis and Niparko), Johns Hopkins University, Baltimore; the Department of Mechanical Engineering (Mr. Mustafa and Drs. Roy and Whitcomb) Johns Hopkins University, Baltimore; the Department of Computer Science (Drs. Hager and Taylor), Johns Hopkins University, Baltimore; and the Department of Biomedical Engineering (M...

Tissue progenitor cells are an attractive target for regenerative therapy. In various organs, bone marrow cell (BMC) therapy has shown promising preliminary results, but to date no definite mechanism has been demonstrated to account for the observed benefit in organ regeneration. Tissue injury and regeneration is invariably accompanied by macrophage infiltration, but their influence upon the pr...