Zonular instability-associated morphologic features in eyes with primary angle closure disease using the swept-source anterior segment - optical coherence tomography system.

BACKGROUND: This study aims to investigate the morphologic features of the crystalline lens in Primary Angle Closure Disease (PACD) patients with zonular instability during cataract surgery using the swept-source CASIA 2 Anterior Segment-Optical Coherence Tomography (AS-OCT) system. METHODS: A total of 398 eyes (125 PACD eyes with zonular instability, 133 PACD eyes with zonular stability, and 140 cataract patient controls) of 398 patients who underwent cataract surgery combined or not glaucoma surgery between January 2021 and January 2023 were enrolled. The crystalline lens parameters were measured by CASIA2 AS-OCT. Then, logistic regression was performed to evaluate the risk factors associated with zonular instability. RESULTS: The results revealed that PACD eyes had a more anterior lens equator position, a steeper anterior curvature of lens, shorter Axial Length (AL), shallower Anterior Chamber Distance (ACD), higher Lens Vault (LV) and thicker Lens Thickness (LT), when compared to eyes in the cataract control group. Furthermore, PACD eyes in the zonular instability group had steeper front R, front Rs and Front Rf, flatter back Rf, thicker lens anterior part thickness, higher lens anterior-to-posterior part thickness ratios, shallower ACD, and greater LV, when compared to PACD eyes with zonular stability. The logistic regression analysis, which was adjusted for age and gender, revealed that zonular instability was positively correlated with anterior part thickness, lens anterior-to-posterior part thickness ratio, and LV, but was negatively correlated with lens anterior radius and ACD. CONCLUSION: Steeper anterior curvature, increased lens anterior part thickness, higher anterior-to-posterior part thickness ratio, shallower ACD, and greater LV are the anatomic features of PACD eyes associated with zonular instability.

Clinicopathological and prognostic significance of SPARC expression in gastric cancer: A meta­analysis and bioinformatics analysis.

Secreted protein acidic and rich in cysteine (SPARC) is a member of the extracellular matrix glycoprotein family that binds to calcium ions. It may bind to a variety of proteins in the extracellular matrix and also compete with cell membrane surface receptors for growth. In the present study, the relationship between SPARC expression in gastric cancer tissues and the clinicopathological characteristics and prognosis of patients with gastric cancer were systematically evaluated. A meta-analysis and bioinformatics analysis were performed using the PubMed, Chinese National Knowledge Infrastructure, Kaplan-Meier (KM)-plotter, The Cancer Genome Atlas (TCGA), Gene Expression Profiling Interactive Analysis (GEPIA), University of ALabama at Birmingham CANcer (UALCAN), Human Protein Atlas (HPA) and Timer databases. SPARC was mainly expressed in tumor mesenchymal cells. The meta-analysis indicated that SPARC expression was higher in gastric cancer tissues than in normal tissues. SPARC was associated with the degree of differentiation and distant metastasis. K-M plotter results indicated that high SPARC expression was negatively associated with overall survival, post-progression survival and progression-free survival rates of patients. According to the Oncomine, GEPIA, UALCAN and HPA databases, SPARC mRNA and protein expression was upregulated in gastric cancer vs. normal tissues and was negatively associated with poor patient prognosis. In the TCGA database, univariate analysis indicated that lymph node metastasis and distant metastasis were associated with the prognosis of patients with gastric cancer. Cox multifactorial analysis suggested that high SPARC expression, age and distant metastasis were important factors affecting the survival time of patients with gastric cancer. Analysis with the Timer database indicated that SPARC was closely associated with the proportion of 7 immune-cell infiltrates in gastric cancer. These findings indicated that high expression of SPARC may be a potential marker of tumorigenesis and metastasis in patients with gastric cancer.

Role of FBXW7 expression in gastric cancer: Meta­analysis and bioinformatics analysis.

F-box/WD repeat domain-containing 7 (FBXW7, also known as CDC4) is a member of the F-box protein family, which is a component of the E3 ubiquitin ligase complex. There is an association between expression of FBXW7 and the prognosis of gastric cancer. Therefore, the search for novel tumor biomarkers is key to predict the occurrence, recurrence and metastasis of gastric cancer. In the present study, systematic meta-analysis and bioinformatics analysis were performed to determine the expression levels of prognostic marker FBXW7 in gastric cancer. A literature search was conducted on August 10, 2022, using PubMed, SinoMed, Wanfang data and China National Knowledge Infrastructure databases. The meta-analysis included six studies and showed that the expression of FBXW7 was significantly downregulated in gastric cancer compared with normal mucosal tissues (P<0.05). FBXW7 expression was positively associated with lymph node metastasis, TNM stage and differentiation (P<0.05). According to the Oncomine database, FBXW7 mRNA expression was higher in gastric cancer than in normal tissue (P<0.05). Kaplan-Meier plots showed that FBXW7 mRNA expression was positively associated with the overall and progression-free survival of patients with gastric cancer. According to the UALCAN and Gene Expression Profiling Interactive Analysis databases, FBXW7 expression was downregulated in gastric cancer compared with normal tissue. FBXW7 may be involved in the entire process of gastric carcinogenesis and its low expression may make it a potential marker for the prognosis of patients with gastric cancer.

Coinheritance of OLFM2 and SIX6 variants in a Chinese family with juvenile-onset primary open-angle glaucoma: A case report.

BACKGROUND: Juvenile-onset primary open-angle glaucoma (JOAG), characterized by severe elevation of intraocular pressure and optic neuropathy prior to the age of 40, is a rare subtype of primary open-angle glaucoma. Several genetic mutations have been associated with JOAG. CASE SUMMARY: The proband patient was a young male, diagnosed with primary open-angle glaucoma at the age of 27. The patient and his unaffected parents who have been excluded from classic genetic mutations for primary open-angle glaucoma were included to explore for other possible genetic variants through whole genome sequencing and bioinformatics analysis. In this trio, we found two heterozygous variants inherited from the parents in the proband: c.281G>A, p.Arg94His in OLFM2 and c.177C>G, p.Ile59Met in SIX6. Both genetic mutations are predicted through bioinformatics analysis to replace evolutionary conserved amino acids, therefore rendering a pathogenic effect on proteins. In contrast, very low frequencies for these genetic mutations were recorded in most common control databases. CONCLUSION: This is the first report on coinherited mutations of OLFM2 and SIX6 in a JOAG family, which shows the complexity of JOAG inheritance. Large-scale clinical screening and molecular functional investigations on these coinherited mutations are imperative to improve our understanding of the development of JOAG.

Blood-retinal barrier as a converging pivot in understanding the initiation and development of retinal diseases.

Clinical ophthalmologists consider each retinal disease as a completely unique entity. However, various retinal diseases, such as uveitis, age-related macular degeneration, diabetic retinopathy, and primary open-angle glaucoma, share a number of common pathogenetic pathways. Whether a retinal disease initiates from direct injury to the blood-retinal barrier (BRB) or a defect/injury to retinal neurons or glia that impairs the BRB secondarily, the BRB is a pivotal point in determining the prognosis as self-limiting and recovering, or developing and progressing to a clinical phenotype. The present review summarizes our current knowledge on the physiology and cellular and molecular pathology of the BRB, which underlies its pivotal role in the initiation and development of common retinal diseases.

Gut Microbiota Reconstruction Following Host Infection with Blood-stage Plasmodium berghei ANKA Strain in a Murine Model.

Malaria remains a global health problem. The relationship between Plasmodium spp. and the gut microbiota as well as the impact of Plasmodium spp. on the gut microbiota in vertebrate hosts is unclear. The aim of the current study was to evaluate the effect of blood-stage Plasmodium parasites on the gut microbiota of mice. The gut microbiota was analyzed by 16S rRNA sequencing and bioinformatic analyses at three stages. The gut microbiota changed during the three phases: the healthy stage, the infection stage, and the cure stage (on the 9th day after malarial elimination). Moreover, the gut microbiota of these infected animals did not recover after malaria infection. There were 254 operational taxonomic units (OTUs) across all three stages, and there were unique strains or OTUs at each stage of the experiment. The percentages of community abundance of 8 OTUs changed significantly (P<0.05). The dominant OTU in both the healthy mice and the mice with malaria was OTU265, while that in the cured mice was OTU234. In addition, the changes in OTU147 were the most noteworthy. Its percentage of community abundance varied greatly, with higher values during malaria than before malaria infection and after malaria elimination. These results indicated that the external environment influenced the gut microbiota after host C57BL/6 mice were infected with blood-stage P. berghei ANKA and that the same was true during and after elimination of blood-stage P. berghei ANKA. In addition, we could not isolate OTU147 for further study. This study identified gut microbiota components that were reconstructed after infection by and elimination of blood-stage P. berghei ANKA in host C57BL/6 mice, and this process was affected by P. berghei ANKA and the external environment of the host.

Transitions of the Understanding and Definition of Primary Glaucoma.

OBJECTIVE: In previous decades, glaucoma has been primarily attributed to elevated intraocular pressure (IOP), but this has gradually been replaced by the development of optic neuropathy as the central concept of glaucoma in developed countries. However, there still remain strong controversies in the definition of glaucoma in China. In this current review, we are going to discuss these controversies and elaborate on the historical transitions of the definition of glaucoma both in China and developed countries. Furthermore, we will briefly describe the "ocular-cranial pressure gradient" theory and discuss the relationship between glaucoma and degenerative diseases of the central nervous system (CNS) in order to show the complex pathogenesis of glaucoma and the importance for the modification to the definition of glaucoma. DATA SOURCES: We performed a comprehensive search in both PubMed and SinoMed using the following keywords: (a) "primary glaucoma" and "guideline," (b) "ocular-cranial pressure gradient," and (c) "glaucoma," "Alzheimer's disease," and "Parkinson's disease." The literature search included the related articles with no restrictions on publication date. STUDY SELECTION: The primary references were Chinese and English articles including (a) original guidelines and expert consensuses of primary glaucoma, (b) reviews focusing on the differences between various versions of these guidelines and consensuses, and (c) papers about ocular-cranial pressure gradient theory and the relationship between glaucoma and CNS degenerative diseases. RESULTS: The definitions and classifications of both primary open-angle glaucoma and primary angle-closure glaucoma differ between Chinese glaucoma consensuses and international primary glaucoma guidelines. Chinese definitions and classifications put more emphasis on the IOP, while international guidelines put more emphasis on the presence of optic neuropathy. The ocular-cranial pressure gradient theory and the research on the relationship between glaucoma and CNS degenerative diseases have provided new directions for exploring the pathogenesis of glaucoma. CONCLUSIONS: As regards the definition and classification of primary glaucoma, we find that there are still some discrepancies between Chinese expert consensuses and international guidelines. Glaucoma is a disease with complex etiologies, while its common characteristic is a specific optic neuropathy. The current definition and understanding of glaucoma is an ongoing and evolving process, reflecting our latest available evidence on its pathogenesis. Chinese ophthalmology community may need to update our guidelines, accommodating these latest developments.

[Immune response in mice induced by complex gene vaccine pcSAG1-ROP5 of Toxoplasma gondii].

OBJECTIVE: To observe the immune response induced by complex gene vaccine pcSAG1-ROP5 of Toxoplasma gondii in mice. METHODS: The recombinant eukaryotic expression plasmids pcSAG1, pcROP5 and pcSAG1-ROP5 were constructed and identified by PCR, restriction enzyme digestion, and sequencing. The three recombinant plasmids were transfected into HeLa cells to express in vitro and identified by Western blotting analysis. Seventy Kunming mice were randomly divided into 5 groups with 14 each, i.e. pcSAG1 group, pcROP5 group, pcSAG1-ROP5 group, blank plasmid group and PBS control group. The mice were immunized intramuscularly with pcSAG1, pcROP5, pcSAG1-ROP5, pcDNA3.1, and PBS, respectively, every two weeks for three times. Sera were collected before each injection and 2 weeks after the last immunization. The titer of mice serum in pcSAG1-ROP5 group combined with recombinant protein SAG1, ROP5 and SAG1-ROP5 and the level of IgG against T. gondii in 5 groups were determined by ELISA. Three weeks after the last immunization, ten mice of each group were challenged with 10(3) tachyzoites of the virulent T. gondii RH strain to observe the survival time. One week later, the rest four mice in each group were sacrificed and the supernatant of cultured splenocytes was collected for the detection of IFN-gamma and IL-4. RESULTS: Western blotting showed that the recombinant plasmids pcSAG1, pcROP5 and pcSAG1-ROP5 were expressed in HeLa cells with M(r) 31 000, 57 000, and 88 000, respectively. The serum titer in pcSAG1-ROP5 group combined with SAG1, ROP5 and SAG1-ROP5 was 1:320, 1:160, and 1:2560, respectively. The IgG level kept rising in pcSAG1, pcROP5 and pcSAG1-ROP5 groups. Two weeks after the last immunization, the IgG level in pcSAG1-ROP5 group was higher than those in other groups (P<0.05). After a lethal challenge of T. gondii RH strain, the survival time of the mice in pcSAG1-ROP5 group was (288 +/- 7) h, which was 48 h and 96h longer than the groups of pcSAG1 and pcROP5, respectively (P< 0.05). Four weeks after the last immunization, IFN-gamma in splenocyte culture of pcSAG1-ROP5 group [(908.52 +/- 6.31) pg/ml] was higher than other groups (P<0.05), with no significant difference in IL-4 (P>0.05). CONCLUSION: Compared with the single gene vaccines pcSAG1 and pcROP5, higher levels of IgG and IFN-gamma and longer survival time are observed in mice immunized with pcSAG1-ROP5.

[Effect of N-acetylcysteine on malondialdehyde and superoxide dismutase in hepatic tissue of mice with Schistosomiasis japonica].

90 mice were randomly divided into six groups: normal control, infected control, long-term drug use group 1 (L1), long-term drug use group 2 (L2), short-term drug use group 1 (S1) and short-term drug use group 2 (S2). Mice in all groups except those in the normal control group were infected with 30 cercariae of Schistosoma japonicum through abdominal skin. N-acetylcysteine (NAC) solution was orally given to mice in L1 and L2 groups, 200 mg/kg and 400 mg/kg, respectively, 2 times/d from the day of infection, while for S1 and S2 groups, 200 mg/kg and 400 mg/kg, respectively, 2 times/d from the 42th day after L2 infection. Mice in the groups of normal control, infected control, L1 and L2 were sacrificed either on day 42 or day 56 after infection, while those in S1 and S2 were sacrificed on day 56 after infection. Number and area of the single egg granuloma were measured with computer image analysis software. The concentration of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in serum and hepatic tissue were detected. The number of "+" single egg granulomas in the liver of mice in L1 was the fewest by 3.04, followed by those in S1, by 4.87. The results indicated that the level of MAD in hepatic tissue of L2 (9.2-9.3 nmol/mg)was markedly lower than that of L1 (P < 0.05), and the level of SOD in hepatic tissue of L1 was 170.00-190.00 U/(g x pro), similar to those of S1 and L2 at the 42th day (P > 0.05), but the level in L2 at the 56th day was close to that of S2 (P > 0.05). Hence, NAC may retard the formation of single egg granulomas in the liver of infected mice, and may regulate the concentration of MDA and the activity of SOD in the liver.

[Molecular cloning and sequence analysis of lactate dehydrogenase gene from Plasmodium vivax Hainan isolate].

Full length sequence of lactate dehydrogenase gene was amplified by PCR from the genomic DNA of Plasmodium vivax Hainan isolate, and named as PvLDH/HN (GenBank No. FJ527750). Sequence analysis showed that the gene had 951 bp, coding 316 aa. Compared with PvLDH/Salvador and PvLDH/Belem, the nucleotide sequence homology of PvLDH/HN was both 99.89%, while the homology of amino acid sequence was 100%. Topology analysis showed that the protein had two transmembrane alpha-helices, which suggested that the protein might be a membrane protein. The major antigen epitope regions (82-95aa) was presented on the protein surface, and formed the specific substrate binding loop, which revealed that it might be an ideal target site for drug action and immunodiagnosis.

[Construction and identification of a full-length cDNA library from Spirometra erinaceieuropaei].

The full-length pBluescript II SK cDNA library of adult Spirometra erinaceieuropaei was constructed by using the SMART method. Data showed that 95.5% of the library was recombinant and the titer of the library was 1.06 x 10(6). The average insert size of the library was about 1.4 kb. Forty-eight randomly selected clones were sequenced. A set of 36 effective expressed sequence tags (ESTs) with the average size of 674 bp was obtained after excluding clones shorter than 450 bp. The unigenes occupied 58.3% of the 36 ESTs. The rate of full-length cDNAs were 57.7% (15/26). The high-quality of full-length cDNA library could be used for large scale EST sequencing.

[Effect of N-acetylcysteine on the egg granuloma in hepatic tissue of mice with Schistosomosis japonica].

OBJECTIVE: To study the effect of N-acetylcysteine (NAC) on the egg granuloma in hepatic tissue of mice infected with Schistosoma japonicum. METHODS: 36 mice were randomly divided into normal group, infected group and NAC group, each with 12 mice. The mice in the latter two groups were each infected with 25+/-2 cercariae of S. japonicum through the skin of abdomen. NAC solution was orally given to the mice of NAC group, 200 mg/kg, 2 times/d from the day of infection through to the 42nd day. Mice in the other 2 groups were given 2 ml normal saline daily. The mice were all sacrificed at the end of the 42nd day and their livers were collected for pathologic observation. Area of the egg granuloma was measured with computer image analysis software. Concentration of nitric oxide (NO) and reduced glutathione hormone (GSH), and the activity of glutathione peroxidase (GSH-PX) in serum and hepatic tissue, and the activity of inducible nitric oxide synthase (iNOS) in the hepatic tissue were all detected. RESULTS: Number of the single egg granuloma of "+,++,+++" grade were 1.80+/-0.25, 1.37+/-0.23 and 0.53+/-0.15 respectively in NAC treated group, which were less than those of infected group (3.70+/-0.28, 2.77+/-0.25 and 2.00+/-0.14 respectively) (P<0.05). The serum NO and GSH concentration was 0.53+/-0.17 and 229.66+/-9.47 respectively in NAC group, lower than those of infected group (2.64+/-0.31 and 312.47+/-18.55 respectively) (P<0.05), but its GSH-PX activity was 1101.99+/-140.81, higher than that of infected group (663.66+/-25.59) (P<0.05). The concentration of NO and GSH, and the activity of iNOS and GSH-PX in hepatic tissue of NAC group were 6.85+/-0.30, 13.44+/-0.40, 358.40+/-19.15 and 110.84+/-10.93 respectively, lower than those in infected group (8.26+/-1.69, 28.40+/-0.56, 1132.44+/-52.82 and 226.26+/-16.25 respectively) (P<0.05). CONCLUSION: NAC may have the effect of retarding pathological change of the liver, which may associate with the decrease of NO and GSH in serum and hepatic tissue and iNOS activity in the tissue.

[Expression changes of Notch-related genes during the differentiation of human mesenchymal stem cells into neurons].

The Notch signaling pathway has been implicated in the regulation of cell-fate decisions such as differentiation of embryo stem cells and neural stem cells into neurons. We cultured human mesenchymal stem cells (hMSCs) in vitro and induced hMSCs to differentiate into neural cells by beta-mercaptoethanol (beta-ME), DMSO and 3-tert-butyl-4-hydroxyanisole (BHA). Immunocytochemistry was utilized to detect neuron-specific enolase (NSE) and Nissl body, and flow cytometry was used to determine cell growth phases. The expressions of signal molecules involved in the Notch pathway such as Notch1, Jagged 1 (JAG1), presenilin 1 (PS1) and hairy and enhancer of split 1(HES1) were observed by RT-PCR and immunofluorescent techniques. The results were as follows: (1) Before induction, the percentage of hMSCs at G(0)/G(1) was 58.5%, and the percentage at S+G(2)/M was 41.5%. After induction, the percentage of hMSCs at G(0)/G(1) increased to 73.1%, 76.2% and 78.1%, respectively on days 2, 4 and 6, and the percentage at S+G(2)/M decreased to 26.8%, 24.8% and 21.9%, respectively; The percentage of NSE-positive cells reached (77+/-0.35) %; Nisslos staining was positive in cytoplasm. (2) Notch1 and JAG1 were both expressed in hMSCs before and after induction, but the mRNA expressions of both Notch1 and JAG1, detected by RT-PCR, decreased obviously after induction(P<0.05). Notch1 mRNA/beta-actin was 1.157, 0.815, 0.756 and 0.570, and JAG1 mRNA/beta-actin was 0.437, 0.350, 0.314 and 0.362, respectively, on days 0, 2, 4 and 6 after induction. The Notch pathway activation participant PS1 mRNA and Notch pathway target gene HES1 mRNA also decreased apparently after induction (P<0.05), and their mRNA/beta-actin was 0.990, 0.449, 0.441, 0.454 and 0.370, 0.256, 0.266, 0.240 on days 0, 2, 4 and 6, respectively. These observations indicate that the expressions of Notch signal molecules were suppressed when hMSCs were induced to differentiate into neural cells. Based on these findings, we propose that low level of Notch signaling activation may contribute to neural cell differentiation.

[The effect of interleukin-1alpha on intraocular pressure in rabbit eyes and its focal side effects].

OBJECTIVE: To investigate the efficiency of interleukin-1alpha on intraocular pressure reduction and its safety. METHODS: 35 New Zealand female rabbits were randomized into seven groups. In group-A, one eye was randomly selected to receive sub-conjunctival injection of 15 ng IL-1alpha, and in group B-D, one eye was injected intracamerally with IL-1alpha 1.5 ng, 15 ng and 40 ng respectively, and the other eye was injected intracamerally with equivalent volume of 0.1% PBS as control. In group-E, one eye was treated with 0.5% timolol eye drops and the other eye was given artificial tear. Groups F and G were treated as group D, and specifically in group-G, both eyes were given IL-1alpha. In group-A to D, the examination of tonometry, slit-lamp biomicroscopy and direct ophthalmoscope were taken before treatment and 24 hours after the treatment and were repeated everyday for 4 days. In group-E, tonometry was applied before treatment and 7 days after treatment. In group-F, aqueous humor of two eyes was aspirated for smear examination 24 and 48 hours after treatment, and corneal endothelium microscope and flash-ERG were done in group-G before and 30 to 40 hours after treatment, and then the eyes were enucleated for histology analysis. RESULTS: IOP of the eyes received IL-1alpha was decreased significantly compared with that of contralateral control eyes in group A to D (P < 0.05). Peaking time of IOP reduction was 72 - 96 hours after treatment, and IOP reduction was continued for over 96 hours. The IOP reduction efficiency in group C and D was more significant than those of group E (P < 0.05). No significant abnormal was found with the examinations of slit-lamp biomicroscopy, ophthalmoscope, corneal endothelium microscopy, flash-ERG, smear and histological observation, except for mild focal conjunctival congestion. CONCLUSION: Intraocular reduction were demonstrated with IL-1alpha treatment, charactered by its strong hypotensive effect, long duration and safety.

[A pilot study on transdifferentiation of skin stem cell in reconstructing corneal epithelium].

OBJECTIVE: To observe the differentiation and development of skin stem cells on corneal stroma and to discuss the possibility of reconstructing corneal epithelium with skin stem cells. METHODS: Pieces of human and rabbit skin were obtained during operation. Rabbit eye balls were taken, and pieces of corneal stroma without epithelium were prepared. Skin stem cells from the rabbit skin and human skin were cultured. The human skin stem cells of the first generation to 4th generation were implanted on the rabbit corneal stroma and cultured. Three rabbits underwent autotransplantation of the rabbit skin stem cells of the first generation to 4th generation on the pieces of corneal stroma with the superficial lamina removed and then fed for 100 approximately 114 days. Another 3 rabbits underwent allotransplantation of the rabbit skin stem cells of first to 4th generation on the pieces of corneal stroma with the superficial lamina removed and then fed for 100 days. Then the rabbits were killed and their eye balls taken out. The rabbit corneas implanted with human or rabbit epithelial cells and the rabbit corneas with the autogeneous or heterogeneous epithelial cells were sliced and underwent immunohistochemistry with human AE5 antibody corresponding to the specific surface marker keratin K3/K12 common to humankind and rabbit, and human epithelial cell keratin K-19 monoclonal antibody. RESULTS: Since the 3(rd) day of transplantation the transplanted human epithelial cells formed multiplayer and were human AE5 antibody and human K19 monoclonal antibody positive. The autotransplanted corneas remained basically transparent without obvious vascular hyperplasia till the cornea specimens were taken. Histological examination showed intact multiplayer epithelium and immunohistochemistry showed human AE5 positive. The allotransplanted\rabbit corneas showed congestion since the 9(th) day. Histological examination showed that the corneas were nor so transparent as the autotransplanted ones and the epithelium was nor intact with a lot of lymphocyte infiltration. CONCLUSION: Corneal epithelium can be reconstructed from skin stem cell, which may be an alternative for constructing autogeneous bioengineered corneas.