Abstract
Background
Little is known about the relevance of circulating progenitor cells in pulmonary arterial hypertension (PAH). We aimed to characterize the circulating CD133+ cells in PAH and tested the hypothesis that CD133 may serve as biomarker.
Patients and Methods
CD133+ cells were analyzed by flow cytometry from peripheral blood of n=20 patients with PAH and their age -and sex-matched controls (n=20). The number of CD133+ population was then correlated with patients' haemodynamics. CD133+ cells were sorted from n=10 PAH and n=10 healthy donors by MACS. RNA was isolated and cDNA was obtained after preamplification step. RT-PCR was performed for the following genes: Oct3/4, SOX2, Nanog, Ki67 and CXRCR4. Immunohistochemistry was performed on n=5 IPAH and n=5 healthy donor lung tissues for CD133, αSMA, vWfa, Ki67 and H&E.
Results
CD133+ cells were elevated in PAH as compared to controls (p<0.0004). CD133+ CD14+ cells were also significantly elevated (p<0.0001) in PAH as compared to controls. The CD133+ cells of bone marrow origin (CD133+CD45+) were also significantly increased (p<0.0004). The number of CD133+ cells correlated with mPAP and PVR. CD133+ cells did not express SOX2, Nanog, Ki67 and CXCR4 on mRNA levels, whereas Oct3/4 mRNA was present in both PAH and healthy controls with no statistically significant difference between the two groups. Immunohistochemistry showed that CD133+ cells were present in the lung tissue and comprised: Type 2 pneumocytes, monocytic cells and undifferentiated cells.
Conclusion
Circulating CD133+ cells are elevated in PAH as compared to controls and their number correlates with the pulmonary hemodynamics. CD133 may serve as a potential biomarker for PAH.
- © 2014 ERS