title: Transplantation of umbilical cord mesenchymal stem cells alleviates pneumonitis of MRL/lpr mice.
abstract: OBJECTIVE
  To investigate whether the umbilical cord mesenchymal stem cells (UC-MSCs) transplantation in the MRL/lpr mice has effect or not on their pneumonitis and the possible mechanisms underlying this treatment.
  
  
  METHODS
  Twenty four 18-week-old MRL/lpr female mice were divided into three groups as following: the group 2 (UC-MSCT group) have been transplanted with 1×10(6) UC-MSCs through caudal vein, the group 3 (multi-UC-MSCT Group) have been transplanted with 1×10(6) UC-MSCs three times and the group 1 (control group) have been treated with 0.5 mL phosphate buffer saline (PBS) as control. The histopathology of the lung was observed. The pulmonary expression of high mobility group box protein-1 (HMGB-1) was measured by western blot and detected by quantitation real time polymerase chain reaction (PCR). Immunohistochemistry method was used to detect HMGB-1 expressions in pulmo.
  
  
  RESULTS
  In comparision to control ground mice, UC-MSCs significantly reduced interstitial pneumonitis in the MRL/lpr mice. The lung peribronchiolar lesion index of UC-MSCT group (1.40±0.24) and multi-UC-MSCT group (1.02±0.29) were significantly decreased as compared to control group (1.95±0.35) (P<0.01). The perivascular lesion index of UC-MSCT group (1.20±0.18) and multi-UC-MSCT group (1.08±0.16) were also significantly reduced as compared to control group (1.56±0.32) (P=0.018, 0.002) and the lung alveolar areas lesion index of control group (1.72±0.34) was significantly increased as compared to UC-MSCT group (1.30±0.21) and multi-UC-MSCT group (1.05±0.15) (P=0.011, 0.000). The lung HMGB-1 protein in UC-MSCT group (0.32±0.04) and in multi-UC-MSCT group (0.28±0.06) were both significantly decreased as compared to that in control group (0.80±0.21) (P<0.05). The level of HMGB-1 mRNA in UC-MSCT group (4.68±0.37) and in multi-UC-MSCT group (4.35±0.10) lung were both significantly decreased as compared to those in control group (16.29±3.84) (P<0.05). In immunohistochemical staining lung sections, high expression of HMGB-1 was found mainly located in the cytoplasm and extracellular matrix of MRL/lpr mice pulmonary epithelial cells, the expression of HMGB-1 in UC-MSCT group and multi-UC-MSCT group was significantly decreased as compared to that in the control group.
  
  
  CONCLUSIONS
  These findings indicate that UC-MSCs have a therapeutic effect on systemic lupus erythematosus (SLE) pneumonitis, possibly by inhibiting HMGB-1 expression, which suggests a potential application of UC-MSCs in the treatment of human lupus.
authors.affiliation: 1 Department of Respiratory Medicine, 2 Department of Rheumatology Medicine, Affiliated Hospital of Nantong University, Nantong 226001, China.
authors.forename: Yanju
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: 1 Department of Respiratory Medicine, 2 Department of Rheumatology Medicine, Affiliated Hospital of Nantong University, Nantong 226001, China.
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Xia
authors.affiliation: 1 Department of Respiratory Medicine, 2 Department of Rheumatology Medicine, Affiliated Hospital of Nantong University, Nantong 226001, China.
authors.forename: Songshi
authors.initials: S
authors.lastname: Ni
authors.affiliation: 1 Department of Respiratory Medicine, 2 Department of Rheumatology Medicine, Affiliated Hospital of Nantong University, Nantong 226001, China.
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Gu
authors.affiliation: 1 Department of Respiratory Medicine, 2 Department of Rheumatology Medicine, Affiliated Hospital of Nantong University, Nantong 226001, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Liu
keywords: Umbilical cord mesenchymal stem cells (UC-MSCs); high mobility group box protein-1 (HMGB-1); pneumonitis; systemic lupus erythematosus (SLE)