Long-term (postnatal day 70) outcome and safety of intratracheal transplantation of human umbilical cord blood-derived mesenchymal stem cells in neonatal hyperoxic lung injury.
OBJECTIVE
This study was performed to evaluate the long-term effects and safety of intratracheal (IT) transplantation of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) in neonatal hyperoxic lung injury at postnatal day (P)70 in a rat model.


METHODS
Newborn Sprague Dawley rat pups were subjected to 14 days of hyperoxia (90% oxygen) within 10 hours after birth and allowed to recover at room air until sacrificed at P70. In the transplantation groups, hUCB-MSCs (5×10⁵) were administered intratracheally at P5. At P70, various organs including the heart, lung, liver, and spleen were histologically examined, and the harvested lungs were assessed for morphometric analyses of alveolarization. ED-1, von Willebrand factor, and human-specific nuclear mitotic apparatus protein (NuMA) staining in the lungs and the hematologic profile of blood were evaluated.


RESULTS
Impaired alveolar and vascular growth, which evidenced by an increased mean linear intercept and decreased amount of von Willebrand factor, respectively, and the hyperoxia-induced inflammatory responses, as evidenced by inflammatory foci and ED-1 positive alveolar macrophages, were attenuated in the P70 rat lungs by IT transplantation of hUCB-MSCs. Although rare, donor cells with human specific NuMA staining were persistently present in the P70 rat lungs. There were no gross or microscopic abnormal findings in the heart, liver, or spleen, related to the MSCs transplantation.


CONCLUSIONS
The protective and beneficial effects of IT transplantation of hUCB-MSCs in neonatal hyperoxic lung injuries were sustained for a prolonged recovery period without any long-term adverse effects up to P70.
Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Korea.
So Yoon
SY
Ahn
Yun Sil
YS
Chang
Soo Yoon
SY
Kim
Dong Kyung
DK
Sung
Eun Sun
ES
Kim
So Yub
SY
Rime
Wook Joon
WJ
Yu
Soo Jin
SJ
Choi
Won Il
WI
Oh
Won Soon
WS
Park
D000818:Animals; D036101:Cord Blood Stem Cell Transplantation; D053331:Ectodysplasins / Q000378:metabolism; D006801:Humans; D018496:Hyperoxia / Q000473:pathology*; D008168:Lung / Q000378:metabolism / Q000473:pathology; D055370:Lung Injury / Q000473:pathology / Q000601:surgery*; D045164:Mesenchymal Stem Cell Transplantation; D023421:Models, Animal; D034521:Nuclear Matrix-Associated Proteins / Q000378:metabolism; D051381:Rats; D014132:Trachea / Q000637:transplantation*; D014841:von Willebrand Factor / Q000378:metabolism
D053331:Ectodysplasins; D034521:Nuclear Matrix-Associated Proteins; C029417:Von Willebrand antigen; D014841:von Willebrand Factor