BACKGROUNDHuman amniotic epithelial cells (HAECs) are able to secrete biologically active neurotrophins such as brain-derived neurotrophic factor and neurotrophin-3, both of which exhibit trophic activities on dopamine neurons. Previous study showed that when human amniotic epithelial cells were transplanted into the striatum of 6-hydroxydopamine (6-OHDA)-induced Parkinson disease rats, the cells could survive and exert functional effects. The purpose of this study was to investigate the survival and the differentiation of human amniotic epithelial cells after being transplanted into the lateral ventricle of Parkinson's disease (PD) rats, and to investigate the effects of grafts on healing PD in models.

METHODSThe Parkinson's model was made with stereotactic microinjection of 6-hydroxydopamine (6-OHDA) into the striatum of a rat. The PD models were divided into two groups: the HAECs group and the normal saline (NS) group. Some untreated rats were taken as the control. The rotational asymmetry induced by apomorphine of the HAECs group and the NS group were measured post cell transplantation. The expression of nestin and vimentin in grafts were determined by immunohistology. Ten weeks after transplantation the density of tyrosine hydroxylase positive cells in the substantia nigra of the HAECs group, NS group and the untreated group was determined. The differentiation of grafts was determined by TH immunohistology. High performance liquid chromatography (HPLC) was used to determine monoamine neurotransmitter levels in the striatum.

RESULTSThe rotational asymmetry induced by apomorphine of the HAECs group was ameliorated significantly compared to the NS group two weeks after transplantation (P < 0.01). The grafts expressed nestin and vimentin five weeks after transplantation. TH immunohistochemistry indicated that the TH positive cells in the substantia nigra of the HAECs group increased significantly compared to the NS group (P < 0.01). Tyrosine hydroxylase (TH) positive cells in the substantia nigra of the HAEC group and the NS group were decreased compared to the untreated group (P < 0.01). Dopamine and DOPAC levels in the striatum of the HAECs group increased significantly compared to the NS group (P < 0.05). Homovanillic acid (HVA) levels in the striatum of the HAECs group increased significantly compared to the NS group (P < 0.01). In addition dopamine, DOPAC, and HVA levels in the striatum and dopamine levels in the cerebrospinal fluid of the HAECs group and the NS group were decreased compared to the untreated group (P < 0.05).

CONCLUSIONSHuman amniotic epithelial cells could be used to ameliorate the rotational asymmetry induced by apomorphine of the PD models. This could have been due to the increased content of dopamine and its metabolic products, DOPAC and HVA, in the striatum in the PD models.

Amnion ; cytology ; Animals ; Apomorphine ; pharmacology ; Chromatography, High Pressure Liquid ; Epithelial Cells ; cytology ; drug effects ; transplantation ; Female ; Homovanillic Acid ; metabolism ; Humans ; Immunohistochemistry ; Oxidopamine ; toxicity ; Parkinsonian Disorders ; chemically induced ; metabolism ; therapy ; Rats ; Rats, Sprague-Dawley

Xenotransplantation, the transplantation of cells, tissues or organs between individuals of different species, would resolve the current shortage of organs, but rejection remains the major hurdle to successful xenotransplantation. In the present study, we analyzed mixed lymphocyte reactions (MLRs) and used 51Cr release assays in order to identify the proliferation and expansion of mouse CD8+ cytotoxic T lymphocyte cells against PK15, PK15/pIL-18 or PK15/mIL-18 cells. In addition, we identified T cell populations in mouse splenocytes and lymph node cells using two-color flow cytometry. It was found that the CD8+T cells of xenograft recipients proliferated extensively and that the survival rates of populations of PK15/mIL-18 or PK15/pIL-18 cells were higher than untransfected controls. Moreover, CD3+T cells were increased in mice injected with PK15 cells or PK15/pIL-18 cells but PK15/pIL-18 cell numbers were lower in lymph nodes than untransfected controls. CD8+T cells numbers were reduced in the lymph nodes of PK15/pIL-18 injected mice. These results suggest that porcine IL-18 regulates anti-pig cellular rejection in C57BL/6 mice.
Transplantation, Heterologous ; Transplantation ; Transgenes/immunology/physiology ; Transfection ; Tissue Distribution ; T-Lymphocytes/metabolism ; Swine ; RNA, Messenger/metabolism ; Phenotype ; Mice, Inbred C57BL ; Mice ; Lymphocyte Culture Test, Mixed ; Lymphocyte Activation ; Kidney/cytology/*immunology ; Interleukin-18/*genetics/metabolism/physiology ; Immunosuppression/*methods ; Graft Rejection/immunology/*prevention & control ; Genetic Vectors/chemical synthesis ; Female ; Epithelial Cells/*drug effects/*transplantation ; Cytokines/metabolism ; Cells, Cultured ; Animals

PURPOSE: To investigate the short-term efficacy of topical immunosuppressive agents on the survival of cultivated allo-conjunctival equivalents. METHODS: Twenty-five eyes of New Zealand white rabbits were included. Temporal conjunctivae were trephined to a diameter of 7.5 mm, and then cultured allo-conjunctival epithelial cells on amniotic membrane were transplanted onto them. Various immunosuppressants including steroid, cyclosporine, and rapamycin were applied topically four times a day for a week. Epithelial defects and graft edema were graded daily. Numbers of inflammatory cells were measured in H&E. PKH26 and cytokeratin 4 and 7 were immunostained. RESULTS: Earlier epithelialization was observed in 1% steroid-treated eyes and defects persisted significantly in 0.5% CsA applied eyes. In histology, PKH26 positive cells considered as donor cells were only found in 1% steroid or 0.01% rapamycin applied eyes. 1% steroid- or 0.01% rapamycin-applied eyes both showed positive staining for keratin-4 and -7. Inflammatory cells were less found in 1% steroid or 0.01% rapamycin treated eyes. CONCLUSIONS: Topical steroid or rapamycin can help to suppress acute inflammation and enhance the acute survival of transplanted conjunctival cells.
Administration, Topical ; Animals ; Cell Count ; *Cell Transplantation ; Cells, Cultured ; Conjunctiva/*cytology ; Cyclosporine/pharmacology ; Epithelial Cells/metabolism/*transplantation ; Female ; Fluorescent Antibody Technique, Indirect ; Graft Survival/*drug effects ; Immunosuppressive Agents/*pharmacology ; Keratin-4/metabolism ; Keratin-7/metabolism ; Male ; Organic Chemicals/metabolism ; Prednisone/pharmacology ; Rabbits ; Sirolimus/pharmacology ; Transplantation, Homologous