Antonella Cotoia, Gilda Cinnella, Giorgina Specchia, Salvatore Grasso, Nadia Rossana Fede, Paolo Luigi Pugliese, Francesca Massenzio, Francesco Sollitto, Domenico Loizzi, Arcangelo Liso, Giuseppe Capotorto, Lucia Mirabella, Michele Loizzi, Michele Dambrosio, Paolo Pelosi
Background: Blood haematopoietic stem cells expressing the CD34 cell surface marker (CD34+) may differentiate under appropriate stimula into a variety of cell types to repair damaged organs. Purposes of this study were to verify whether lung surgical trauma can activate bone marrow mobilizing peripheral CD34+ cells and the time course of their activation.
Methods and findings: In fifty-one patients undergoing elective surgical lung resection under general anesthesia, ASA II-III, without chronic obstructive pulmonary disease, blood samples for white blood cells (WBC) and circulating blood CD34+ were collected before surgery (T0), at 24 (T24h) and 72 (T72h) hours, 5 (T5d) and 7 (T7d) days postoperatively. CD34+ cells quantification was performed by flow cytometry. A hierarchical clustering analysis identified two clusters based on the CD34+ time course: in cluster #1 (14 patients), CD34+ decreased by 46% on T24h (p=0.0023 vs T0) and then increased constantly reaching 230% on T7d (p=0.00016 vs all previous time points), in cluster #2 (37 patients), CD34+ remained stable throughout the study. Patients entering cluster #1 were younger (58+4 years vs 66+1 years, p=0.03), had a higher baseline CD34+ count (on T0 CD34+ 2.55+1.5 n/10-3 vs 1.2+0.57 n/10-3, p=0.0023) and the pre-operative FEV1/FVC was significantly higher (95.66 vs 76.6, p=0.02).
Conclusions: Our data show that peripheral blood CD34+ are mobilized from the bone marrow in patients undergoing lung resection and their count seems to be correlated with WBC and CD34+ basal values and with patients age.