Regeneration of pathological pulmonary vascular bed by endothelial progenitor cell transplantation

2006 Fiscal Year Final Research Report Summary

• Project/Area Number: 17591473
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Thoracic surgery
• Research Institution: The University of Tokushima
• Principal Investigator: KITAICHI Takashi The University of Tokushima, Institute of Health Biosciences, assistant, 大学院ヘルスバイオサイエンス研究部, 助手 (20335813)
• Co-Investigator(Kenkyū-buntansha): KITAGAWA Tetsuya The University of Tokushima, Institute of Health Biosciences, professor, 大学院ヘルスバイオサイエンス研究部, 教授 (80240886) ; MASUDA Yutaka The University of Tokushima, Institute of Health Biosciences, lecturer, 大学院ヘルスバイオサイエンス研究部, 講師 (20314875)
• Project Period (FY): 2005 – 2006
• Keywords: pulmonary neovasculaization / mononuclear cell / monocrotaline / pulmonary hypertension

Research Abstract

Objectives : 1. Is it possible transplantation of endothelial progenitor cell (EPC). induce anatomical and functional regeneration of pathological obstructed or hypoplastic pulmonary vascular bed? 2. What is the best way to transplant the EPC to pathological lung?
Methods : (1) Female B6 mouse (8-10 week old) were injected 80mg/kg monocrotalin (MCT) intra-peritonially. (2) 4 weeks after MCT injection, mononuclear cell 1(1 X 10^6/0.2ml) which were extracted from femurs and tibias of other mice was injected into orbital vein. (3) 4 weeks after mononuclear cell (MNC) transplantation, mice were sacrificed to examined neovascularization in pulmonary vascular bed. Pulmonary artery number, medial thickness of pulmonary artery which is estimated medial thickness/ vascular diameter and the weight of right ventricular (RV) muscle which is estimated RV muscle weight/ ventricular septum and left ventricular muscle were examined.
Results : (1) Pulmonary artery number; control group was 5.0 ± 2.0. and MNC transplantation group was 17± 3.6. (2) Medial thickness; control group was 0.21± 0.05 and MNC transplantation group was 0.08 ± 0.02. (3) RV weight; control group was 0.29± 0.01 and MNC transplantation group was 0.21 ±0.02.
Discussion : Pulmonary artery number significantly increased and medial thickness and RV muscle weight decreased in MNC transplantation group. That mean pulmonary hypertension was decreased by pulmonary neovascularization. So MNC transplantation is possibly utilized in regeneration of pathological obstructed or hypoplastic pulmonary vascular bed clinically. Furthermore, different transplantation methods, that is direct injection to lung tissue or transbronchial injection, should be estimated.