Oral tolerance describes the phenomenon that orally administered proteins induce systemic hyporesponsiveness to the protein fed. The primary mechanisms by which oral tolerance is mediated include clonal deletion, clonal anergy and active cellular suppression through gut-associated lymphoid tissue(GALT). Low doses favor active suppression mediated by Th2 and Th3 cells, whereas high doses favor deletion and anergy mediated by Th1 and Th2 cells. Oral tolerance is an effective and specific approach without toxicity. In recent years, it has been used successfully to treat autoimmune diseases in model animals and patients. The article discussed the mechanisms and advances of oral tolerance for the purpose of providing new ways of treat autoimmune diseases.

Although allograft corneal transplantation has made great progress,keratoprothesis implantation is the only one hope, for both the patients who has fleshy pannus corneal vitiligo and the patients with the failure corneal transplantation surgery whose far sight is only light perceptions to recover their eye sight. To gain success and reduce complications, a lot of work has been done in keratoprosthesis materials and type, but heterogeneity and bio-compatibility are not solved totally. Because of development in the cell culture and tissue engineering, cornea ex vivo culture has gain a critical success. From cell option to carrier using, reconstructed three dimensional culture and epithelium equivalent mimicked human corneas in key morphology and function and were used in basic and clinical investigation. This article reviews the development of materials of keratoprosthesis and tissue engineering cornea.

AIM: To observe the effect of diterpenoid compound 5F of Pteris semipinnate L on apoptosis in cultured human pterygium body fibroblasts(HPFs).METHODS: Fibroblasts collected from human pterygium body were cultured in vitro with 5F at different time point.Transmission electron microscope(TEM) was used to observe the ultrastructure changes of the HPFs.The changes of the cell cycle and apoptosis of HPFs were evaluated with flow cytometry(FCM).RESULTS: 5F at the concentration of 32 mg/L induced HPF apoptosis at various time points.CONCLUSION: 5F induces HPFs apoptosis.Apoptotic cells are evolved to necrosis with the prolongation of the time.These findings indicate that 5F has a potential clinical value.

AIM:To study whether three kinds of rabbit corneal cells can grow well on fibrin glue (FG) constructed in vitro, and investigate the feasibility of FG for the scaffold of cell sheet engineering. METHODS: Three kinds of corneal cells were seeded on FG which was produced in vivo. Cell growth on FG was examined as follows: (1) by inverted microscope; (2) histologically by hematoxylin and eosin; (3) by scanning electron microscopy. RESULTS: Fibrin glue prepared was smooth and transparent. With cell growth, FG degradated partly, then obtained cell sheet engineering only with a small amount of FG. Corneal cells generated well on the fibrin glue in vitro and maintained the physiological state of cells. Corneal epithelial cells formed unilaminar and stratified layers and cellular joins. Corneal endothelial cells formed round or polygon, the same size cells and lined up tightly. Corneal stroma cells formed triangle and arborization, cell-cell junction was obvious, and formed network link. CONCLUSION: Fibrin glue is well compatible with three kinds of corneal cells, which can construct tissue engineered cell sheet with fibrin glue, so as to reconstruct ocular surface.

[ABSTRACT]AIM:ToinvestigatethepromotingroleofTranswellcontactco-culturesysteminthegrowthand differentiation of single-dissociated induced pluripotent stem cells (iPSCs).METHODS:Bovine corneal endothelial cells (CECs) at passage 1~2 (P1~2) were seeded on the underside of Transwell inserts placed into culture plates and were cultured in 37 ℃and 5%CO2 for 8 h.Accutase digestion and 40μm filter process disaggregated colony-aggregated iPSCs into single-dissociated iPSCs , and the cells were seeded on the inside of Transwell inserts with CECs in medium of mTeSR 1 for 3 d and then in low-glucose DMEM supplemented with 10% FBS for 2 weeks.The characteristics and differentiation markers were evaluated by real-time fluorescence quantitative polymerase chain reaction ( qPCR ) , immunofluorescence staining, live&dead cell staining and alkaline phosphatase (ALP) staining.The group of iPSCs cultured in conventional medium was used as control group 1.The group of single-dissociated iPSCs co-cultured with CECs was set as experimental group, while single-dissociated iPSCs without co-culture were as control group 2.RESULTS: The bovine CECs showed typical hexagonal cobblestone shape .iPSCs showed colony-like growth , while became single-dissociated cells after Tran-swell contact co-culture with bovine CECs for 3 d.The single-dissociated iPSCs positively expressed the undifferentiated markers, Nanog and Oct4.The mRNA expression levels of Nanog , Oct4 and Sox2 between experimental group and control group 1 were both positive and had no statistical significance difference (P>0.05).The dead cells in experimental group decreased significantly, and there was statistically significant difference compared to control group 2 (P<0.01).After 14 d of induced differentiation co-culture , the single-dissociated iPSCs showed rather uniform polygonal morphology , increased dimension and no obvious colony existence .Negative ALP staining, positive immunofluorescence staining for ZO-1, AQP1 and CD31, and negative for CD34 and CD133 were also observed.The results of qPCR showed that the mRNA expression of Oct4, Nanog and Sox2 significantly decreased , and had statistically significant difference compared with control group 1 (P<0.01).CONCLUSION: When co-cultured with bovine CECs, iPSCs morphologically changed to endothelial-like cells and expressed some markers of CECs .Transwell contact co-culture system not only enhances the growth of single-dis-sociated iPSCs , but also promotes their differentiation .

[ ABSTRACT] AIM:To investigate the effect of maxadilan, which specifically activates pituitary adenylate cycla-se-activating polypeptide type I receptor (PAC1 receptor), on the proliferation, apoptosis and differentiation potential of human adipose-derived stem cells ( ASCs) .METHODS:ASCs from human adipose tissue were isolated by enzymatic di-gestion and cultured.ASCs were confirmed by the analysis of the markers for cell phenotypes by flow cytometry ( FCM) and adipogenic/osteogenic induction.The effect of maxadilan on ASCs viability was analyzed by CCK-8 assay and FCM.ASCs were irradiated by ultraviolet C ( UVC) at 254 nm and the absorbance of apoptotic ASCs induced by various doses of UVC was measured by CCK-8 assay.ASCs were exposed to 702 J/m2 UVC for 24 h to induce apoptosis.The effect of maxadilan on ASC apoptosis was analyzed by FCM and the determination of caspase 3 and caspase 9 levels.RESULTS:Adipose-de-rived stem cells were confirmed by the detection of the positive expression of cell phenotypes including CD29, CD44, CD59 and CD105 by FCM.The data of CCK-8 assay revealed that ASCs treated with maxadilan (80 nmol/L) had the strongest ability of proliferation.The data of FCM also demonstrated that the addition of 80 nmol/L maxadilan to ASCs in experimen-tal group markedly improved the proliferation capacity of the cells compared with control group (P<0.05).The apoptosis of ASCs exposed to 702 J/m2UVC was dramatically inhibited by the treatment with maxadilan (80 nmol/L).Such process involved the caspase signaling pathway including caspase 3 and caspase 9.There was statistical significance (P<0.05) between experiment group ( ASCs irradiated by UVC and supplemented with maxadilan) and control group ( ASCs only irra-diated by UVC) .Meanwhile, adipogenic and osteogenic differentiation potentials were both positive in experiment group and control group.CONCLUSION:Maxadilan promotes proliferation and inhibits apoptosis of the ASCs.The differentia-tion potential of ASCs toward adipogenic and osteogenic lineages wouldn’ t be altered by maxadilan.Maxadilan would bene-fit to growth and expansion of ASCs in vitro.

BACKGROUND:With the deepen understanding on the biological function of Rho/ROCK pathway, new ROCK inhibitors continue to be discovered, and ROCK inhibitors show good promoting effects on the survival, proliferation and migration of keratocytes. Research on ROCK inhibitors wil provide more donor materials or seed cels for regenerative medicine and clinical cel transplantation. OBJECTIVE:To summarize and explore the progress in the treatment and application of corneal disease using the ROCK inhibitors Y-27632 and Y-39983. METHODS:The PubMed database and CNKI database were retrieved by computer to search the relevant literature published between 2008 to 2015 using the key words of “corneal endothelial cel, corneal epithelial cel, ROCK inhibitor, Y-39983, Y-27632” in English and Chinese, respectively. Relevant articles in line with the theme were screened and analyzed. RESULTS AND CONCLUSION:Totaly 264 papers were initialy searched. At last, 45 papers were selected. Currently there are two main ROCK inhibitors: Y-27632 and Y-39983, but both of which are stil in basic research stage and clinical testing stage. Y-27632 promotes the proliferation and activity of corneal epithelial stem cel after resuscitation; Y-39983 as a novel ROCK inhibitor can be better to inhibit Rho kinases activity than Y-27632, thereby more effectively promoting the healing of the corneal endothelium. There are many studies on the application of ROCK inhibitors in corneal treatment, but not a stable method established to obtain seed cels. Each method has its own advantages and disadvantages, and how to overcome these disadvantages and to find fast and stable access to seed cels is the future direction of development.

AIM: To observe the effect of cornus of ficinalis glycosides(COG) ophthalmic solution on the corneal allograft rejection by topical instillation. METHODS: The corneal transplantation model on the closed colony rats was established. The rejection time of all animals was recorded and compared by slit-lamp microscope. The pathologic changes were measured by immunohistochemistry and scanning electron microscope.RESULTS: The histopathological and immunohistochemistry findings showed that the lymphocytes, neovascularity and the expression of ICAM-1 in COG-treated group were significantly fewer than that in control group at 15 d after operation.CONCLUSION: COG ophthalmic solution prevents and suppresses the corneal allograft rejection.

AIM: To investigate the influence of the cornus officinalis glycosides (COG) on immunological function of corneal transplantation model of rats, and to clarify the immunosuppressive mechanism of COG through observing the activation of lymphocytes in blood. METHODS: Wister rats were used as recipients and SD rats were used as corneal graft donors, then the corneal allografts transplantation model on the closed colony rats were set up. Splenocytes proliferation and mixed lymphocyte reaction of Wister rats activated by ConA were observed. The phenotype change of CD4, CD8, CD25 in blood in different time postoperatively were observed by the di-sign flow cytometry, and the rate of CD4/CD8 was calculated. RESULTS: 1. The COG suppressed the proliferation of T lymphocytes and one-way mixed lymphocyte reaction on the corneal allografting. 2. The phenotype change of lymphocytes in boold was as follows: there was no significant difference between the different time of the CD4, CD8 expression and the CD4/CD8 rate in blood of the control group. The CD4 positive cells expressed CD25 postoperatively increased obviously. The CD4/CD8 rate of medicine group had the tendency to decrease. The CD4 positive cells expressed CD25 postoperation in the medicine group were less than that in the control group obviously. CONCLUSION: The suppression of the T lymphocyte proliferation, mixed lymphocyte reaction, CD molecule expressed by the activated T lymphocytes and the IL-2 receptor expression may be the main immunosuppressive mechanisms of Cornus officinalis glycosides on the cell-mediated immunity.

0.05), the expression of CD4+ was increased in rabbit corneal stroma (P