CD34 and pulmonary emphysema: According to our data, emphysema of different etiological factors (elastase, cigarette smoke extract, D-galactosamine hydrochloride, tyrosine kinase inhibitor SU5416) mobilizes EPC with the phenotype CD45−CD309+, CD45−CD31+CD34+ and/or CD45−CD309+CD117+ in regeneration of the alveolar endothelium [34].