After more than ten years of development, retinal organoid (RO) based on pluripotent stem cells can highly simulate the development process of human retina, provide insight into the mechanism of retinal development and provide new treatments for retinal diseases.At present, RO has been widely used in the research of the mechanism and treatment of retinal diseases, especially in retinitis pigmentosa (RP).This review summarizes the methods of preparing RO from human pluripotent stem cells, and elaborates the mechanism and therapeutic application of RO-RP disease model in different mutated genes such as PRPF31, RPGR, CRB1, RP2, IMPG2, NR2E3, USH2A, PDE6B and TRNT1, as well as the research progress of RO in drug screening, drug toxicity testing, gene therapy and cell therapy, and discusses the research and application challenges of RO.

Gut microbiome is an important part of maintaining human homeostasis.In recent years, with the rapid development of sequencing technologies such as 16S rRNA and metagenome, people have a deeper and more comprehensive understanding about microorganisms.Studies in animals and humans have confirmed that the gut microbiome is not only involved in the pathological process of systemic diseases such as immune, metabolic and neurological disorders, but is also closely related to eye diseases.Factors such as host high blood glucose, immune disorders, aging, high intraocular pressure can cause gut microbiota dysbiosis and increase gut-blood barrier permeability.Lipopolysaccharide, peptidoglycan and other pathogen-associated molecular patterns enter the systemic circulation through the damaged gut barrier and eventually reach the retina and uveitis where they participate the immune and inflammatory response process.In addition, gut-derived host immune cells or injury-related molecular patterns may exacerbate the ocular inflammatory cascade.At the same time, metabolites of microbiota, including those induced by diet and environment factors, such as bilirubin, bile acids and short-chain fatty acids, are involved in the progression of retinal diseases via regulating immune T cell balance, miRNA expression and retinal cell inflammatory activation.This article aims to review the domestic and foreign studies on gut microbiome in diabetic retinopathy, uveitis, age-related macular degeneration and glaucoma in recent years, and discuss the possible mechanisms of gut microbiome in eye diseases via the gut-retina axis in order to provide some new ideas for further study and treatment of eye diseases.

AIM: To explore the synthesis of thermo-sensitive poly N-isopropylacry-lamide(PNIPAAm)and the petri dish grafted with PNIPAAm hydrogels by the electron accelerator, as well as the growth conditions and the biological characteristics of rabbit corneal stromal cells on thermo-sensitive PNIPAAm hydrogels, and the cell sheets obtained from the PNIPAAm hydrogels.METHODS: NIPAAm monomer was dissolved in 2-propanol at concentrations of 55% with 0.5% N,N'-Methylenebisacry-lamide(MBA). Solution(70 μL)was added and spread uniformly over 35 mm petri dish. These dishes were immediately subjected to irradiation. After follow-up treatment, rabbit corneal stromal cells were cultured on thermo-sensitive petri dish in vitro.RESULTS: According to the monomer formula and radiation synthesis scheme in this experiment, PNIPAAm can be synthesized on the surface of the petri dish. Rabbit corneal stromal cells grew well in the thermo- sensitive surface and can be separated into sheets.CONCLUSION: The single and multilayer carrier-free cell sheets can be obtained from the use of thermo-sensitive petri dish.

Several mutant genes for inherited retinal diseases have been identified, but effective treatments are still lacking.The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) system can edit human genomic DNA by nonhomologous end joining or homology-directed repair, offering more possibilities for the treatment of hereditary retinal diseases.CRISPR/Cas9 not only can genetically correct patient-derived induced pluripotent stem cells (iPSCs) to observe their differentiation into retinal cells thereby, thereby exploring the pathogenesis of the disease and implementing cell therapy, but can also be delivered to the body via vectors and directly act on target cells to achieve in vivo gene editing.CRISPR/Cas9 gene editing technology in hereditary retinal diseases has been mainly used in retinitis pigmentosa, hereditary X-linked juvenile retinoschisis, and Leber congenital amaurosis 10, of which the in vitro application of CRISPR/Cas9 for Leber congenital amaurosis 10 has entered the clinical trial stage.In this paper, we reviewed the mechanism and key advances of CRISPR/Cas9 and provided an overview of gene editing in IRDs.

Objective:To prepare a drug release system of drug-loaded cross-linked decellularized corneal stromal lenticules and evaluate its drug release characteristics in vitro. Methods:Lenticules were obtained during femtosecond laser-assisted small incision lenticule extraction (SMILE) surgery in Chongqing Aier Ophthalmology Hospital.Decellularized corneal stromal lenticules were prepared using high concentration sodium chloride (NaCl) combining nuclease.The decellularized corneal stromal lenticules were randomly divided into normal group, 0.5% levofloxacin group, 3% levofloxacin group and 5% levofloxacin group, with 4 lenticules in each group.The lenticules did not receive any treatment in the normal group, and drug-loading those were soaked in different doses of levofloxacin solution for three hours according to grouping.In the crosslinking test, 12 decellularized corneal stromal lenticules were randomly divided into non-crosslinking group, 0.01 mmol 1-(3-dimethylamino) propylimine (EDC) group, 0.05 mmol EDC group and 0.25 mmol EDC group.The lenticules for cross-linking were soaked in different contents of mixed solution of EDC with N-hydroxysuccinyl (NHS) for four hours respectively according to grouping, and then in 3% levofloxacin solution for three hours.Only 3% levofloxacin solution soaking was carried in the non-crosslinking group.High performance liquid chromatography (HPLC) was employed to detect the drug release concentration of the lenticules, and spectral scanning method was performed to measure light transittance of the lenticules.The surface ultrastructure of the decellularized lenticules among different cross-linking groups was examined and compared with scanning electron microscope.The use of the human corneal lenticules was approved by an Ethics Committee of Chongqing Aier Ophthalmology Hospital (No.2019012). Written informed consent was obtained from each patient before surgery.Results:The release concentrations of decellularized corneal stroma lenticules were significantly different at 1 day, 7, 14, and 21 days among 0.5%, 3%, and 5% levofloxacin group ( P<0.05) or also among the 0.01 mmol EDC, 0.05 mmol EDC, and 0.25 mmol EDC cross-linked groups ( P<0.01). The drug release concentrations in 0.05 mmol EDC group were the highest at various time points, and the release time of the three cross-linked groups lasted until 21 days after release concentrations of decellularized corneal stroma lenticules.The drug release concentrations in cross-linked groups and non-crosslinking group were gradually declined with the prolong of drug-loading time, showing a significant difference at different time points ( P<0.05). The transmittance of the lenticules was (88.68±1.19)% and (91.55±1.16)% in the non-crosslinking group and normal group, respectively, with no significant difference ( P>0.05). The average transmittance of the lenticules was significantly reduced in the drug-loaded groups compared with the normal group ( P<0.05). The smaller collagen fiber voids and closely arranged collagen fibers were displayed in the cross-linking groups under the scanning electron microscope with the best effect in the 0.25 mmol EDC group. Conclusions:EDC/NHS cross-linking can improve the drug-loading effect of decellularized corneal stromal lenticules probably by lessening collagen fiber voids.The drug-loaded cross-linked decellularized corneal stromal lenticules have a good drug release effect in vitro.

Optogenetics is a genetic technique that applies illumination with certain wavelength to modulate the biological activity of cells or subcellular components accurately.This technique is friendly to researchers of ophthalmology due to characteristics of the eyes including transparency, accessibility and comparative independence.Optogenetics can be used in retinal neurons, such as retinal ganglion cells (RGCs), even extended to vascular endothelial cells, immune cells and other ocular cells or cell substructures, which can further our understanding of ocular physiology and provide potential, therapeutic approaches for neurodegenerative diseases, vascular diseases, inflammation and other eye-related diseases.Improvement in effectiveness, safety and comfort is pivotal for this technique to expand application in ophthalmology and for its function to reach the physiology state of nomal eyes.In this review, a comprehensive analysis of optogenetics progress in ophthalmology was performed.Challenges in imaging including light sensitivity, spatial resolution and temporal resolution, and problems in expression involving local and systemic safety, specificity and persistence were reviewed.

Anti-platelet specific antibody is one of the most important reasons leading to thrombocytopenia and megakaryocyte dysmaturity. The detection of platelet autoantibodies is an important step in the diagnosis of ITP because of the absence of specific clinic feature. The monoclonal antibody-specific immobilization of platelet antigens (MAIPA) has become a "gold standard" for determination of PLT specific antibody, which has high specificity and low sensitivity. However, this assay is time-consuming and tedious work. Routine use of this assay in hospital is difficult. Recently, some researches reporded the cytometric bead assay that has higher sensitivity than MAIPA, and so probably solves the problem of time-consuming partly, that also can use different beads for simultaneous detection. This review focuses on recent progress of the cytometric bead assay.
Antibodies ; Antibodies, Monoclonal ; Antigens, Human Platelet ; Blood Platelets ; Humans ; Megakaryocytes ; Thrombocytopenia

[ 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.

Most Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) patients often show rapid recurrence and development of ABL kinase domain (KD) mutation after tyrosine kinase inhibitor (TKI) treatment. To further investigate the mechanism of Ph(+) ALL fast relapse after TKI treatment, ABL KD mutation in 35 Chinese Ph(+) ALL with TKI resistance was detected by direct sequencing. The results showed that 77.1% (27/35) Ph(+) ALL patients with TKI resistance had ABL KD mutation and 55.6% (15/27) Ph(+) ALL patients with ABL KD mutation had T315I. Interestingly, 77.8% (21/27) Ph(+)ALL showed ABL mutation G: C→A:T, including T315I, E255K and E459K. Furthermore, all the Ph(+) ALL patients with two or more ABL KD mutations collaborated with complex chromosome abnormality and all the TKI-resistant Ph(+) ALL patients, whose karyotype progressed from simple t (9;22) into complex, developed ABL KD mutation. Moreover, the expression level of uracil-DNA glycosylase UNG2, which inhibits G:C→A:T transition in genomic DNA, decreased in Ph(+) ALL with TKI-resistance compared to that in newly diagnosis Ph(+) ALL. It is concluded that there is a high frequent ABL KD G:C→A:T mutation and a high genomic instability in Chinese TKI-resistant Ph(+) ALL. In addition, the decreased UNG2 expression in TKI-resistant Ph(+) ALL probably contributes to their high rate of ABL KD G:C→A:T mutation.
Adolescent ; Adult ; Asian Continental Ancestry Group ; genetics ; DNA Glycosylases ; genetics ; Drug Resistance, Neoplasm ; genetics ; Female ; Humans ; Male ; Middle Aged ; Point Mutation ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; Protein Kinase Inhibitors ; pharmacology ; Uracil-DNA Glycosidase ; genetics