Challenges and opportunities for the future of stem cell therapy for lung diseases

In this era of striving for personalized medicine approaches for complex diseases, preclinical studies have excited the field through their demonstration of the promise of stem cell therapy for the treatment of various lung diseases; with the most beneficial effects of stem cell-based strategies in preclinical settings originating from their antimicrobial, anti-inflammatory, and immunomodulatory properties. Although many lung disorders involve an inflammatory component, effective stem cell therapy in patients has not been realized yet for the majority of lung diseases and there are still multiple hurdles to be overcome. While beneficial effects have been realized in clinical studies of CF, results from clinical studies in other lung diseases have been disappointing to date. We discuss the questions that should be addressed before considering administration of stem cells or their derivatives in a phase I studies. We should prevent stem cell tourism, where cell-based therapies are being marketed to extremely vulnerable patient populations and their caregivers. Unproven and often unsafe stem cell treatment practices can mislead patients into participating in often very expensive, unregulated, unethical, and unsafe treatments, which are not covered by insurance. Here, the education of patients, caregivers and of pulmonologists who are not familiar with the stem cell field will be of great value.