Human amniotic membrane-derived mesenchymal stem cells (hAM-MSCs) are capable of differentiating into several lineages and possess immunomodulatory properties. In this study, we investigated the soluble factor-mediated immunomodulatory effects of hAM-MSCs. Mitogen-induced peripheral blood mononuclear cell (PBMC) proliferation was suppressed by hAM-MSCs in a dose-dependent manner as well as hAM-MSC culture supernatant. Moreover, interferon-gamma and interleukin (IL)-17 production significantly decreased from PBMC, whereas IL-10 from PBMCs and transforming growth factor beta (TGF-beta) production from hAM-MSCs significantly increased in co-cultures of hAM-MSCs and PBMCs. Production of several MSC factors, including hepatocyte growth factor (HGF), TGF-beta, prostaglandin E2 (PGE2), and indoleamine 2, 3 dioxygenase (IDO), increased significantly in hAM-MSCs co-cultured with PBMCs. These results indicate that the immunomodulatory effects of hAM-MSCs may be associated with soluble factors (TGF-beta, HGF, PGE2, and IDO), suggesting that hAM-MSCs may have potential clinical use in regenerative medicine.
Amnion/cytology/*immunology ; Cell Differentiation/immunology ; Coculture Techniques ; Dinoprostone/genetics/immunology ; Female ; Hepatocyte Growth Factor/genetics/immunology ; Humans ; Immunologic Factors/*immunology ; Immunophenotyping ; Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics/immunology ; Interferon-gamma/immunology ; Interleukin-10/analysis/immunology ; Interleukin-17/analysis/immunology ; Leukocytes, Mononuclear/cytology/immunology ; Mesenchymal Stem Cells/cytology/*immunology ; Pregnancy ; RNA, Messenger/chemistry/genetics ; Regenerative Medicine/methods ; Reverse Transcriptase Polymerase Chain Reaction ; Transforming Growth Factor beta/genetics/immunology

OBJECTIVETo study the influence of hepatocyte growth factor (HGF) antibody on the lung expression level of matrix metalloproteinases-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1).

METHODSThirty male Wistar rats were randomly divided into 3 groups: control group, model group, and intervention group. Endotoxin was intratracheally infused in the model and intervention groups. HGF antibody was injected in the rats of the intervention group from day 1 to day 14, while the same volume of saline was injected in the control group. The rats were sacrificed on day 28 after endotoxin treatment. The amounts of MMP-9 mRNA and TIMP-1 mRNA were measured by reverse transcription-polymerase chain reaction, and protein expression levels of MMP-9 and TIMP-1 were measured by immunohistochemistry.

RESULTSIn the model group, both mRNA and protein expression levels of TIMP-1 were significantly increased, the same as MMP-9. In the intervention group, the increase of TIMP-1 was remarkably reduced compared with the model group, while the mRNA and protein expression levels of MMP-9 were still increased.

CONCLUSIONHGF activity may accelerate the repair of lung injury through contrary regulating the expression levels of TIMP-1 and MMP-9.

Acute Lung Injury ; metabolism ; pathology ; Animals ; Antibodies ; immunology ; Hepatocyte Growth Factor ; physiology ; Male ; Matrix Metalloproteinase 9 ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar ; Tissue Inhibitor of Metalloproteinase-1 ; analysis ; genetics

Autocrine stimulation via coexpression of hepatocyte growth factor (HGF) and its receptor (Met) has been reported in many human sarcomas, but few in carcinomas. In this report, we found that one gastric cancer cell line, SNU-484, among 11 gastric cell lines tested has an autocrine HGF- Met stimulation. RT-PCR, ELISA and scattering assay using MDCK cells revealed that SNU-484 cells secreted a significant amount of active HGF (about 1.25 +/- 0.41 ng/24 h/106 cells) into conditioned medium. Resultantly, Met in this cell line was constitutively phosphorylated. Neutralizing antibodies against HGF reduced the tyrosine phosphorylation of Met, resulting in the inhibition of cell proliferation and migration (P <0.005). To the best of our knowledge, this is the first report on autocrine HGF-Met signaling in a gastric cancer cell line. Our observations with SNU-484 cells suggest that HGF is involved in the development and/or progression of some gastric carcinoma through an autocrine mechanism.
Animals ; Antibodies, Neoplasm/immunology ; *Autocrine Communication ; *Cell Movement ; Cell Proliferation ; Culture Media, Conditioned/pharmacology ; Dogs ; Enzyme-Linked Immunosorbent Assay ; Hepatocyte Growth Factor/immunology/*pharmacology ; Neutralization Tests ; Phosphorylation ; Proto-Oncogene Protein c-met/genetics/*metabolism ; Research Support, Non-U.S. Gov't ; Reverse Transcriptase Polymerase Chain Reaction ; Stomach Neoplasms/*immunology/metabolism/pathology ; Tumor Cells, Cultured ; Tyrosine/metabolism