The Effect of Amniotic Membrane Transplantation or Conjunctival Autografts on the Tear Mucins MUC5A and MUC2 After Pterygium Resection: A Six-Month Follow-Up.

Purpose: Pterygium is an ocular surface disease characterized by the invasion of fibrovascular tissue from the bulbar conjunctiva to the cornea and is associated with abnormal tear function caused by changes in tear composition and osmolarity. In this study, the effect of two different surgical techniques to remove primary pterygium: conjunctival autograft surgery (CAG) and amniotic membrane transplantation (AMT), on changes in MUC2 and MUC5AC tear mucins concentration were evaluated. Methods: Forty-four patients (>18 years old) with primary unilateral pterygium (> 1.0 mm long, measured from the limbus to the apex on the cornea) were randomly enrolled, and assigned to the AMT or CAG group by using the permuted block technique. Patients with systemic inflammatory diseases or other eye comorbidities were excluded from the study. Tear break-up time (TBUT) and best-corrected visual acuity (BCVA) assessments were performed before surgery and at 1, 3, and 6 months after surgery. Tears were collected concurrently with the clinical evaluations, and MUC2 and MUC5AC concentrations were subsequently measured by means of ELISA. Results: At 6 months after CAG or AMT, TBUT and BCVA were significantly lower (P < 0.05) in comparison with the baseline values in the study subjects. The tear mucin concentrations of both MUC2 and MUC5AC were significantly higher (P < 0.0001) in patients with pterygium before any surgical procedure than in healthy individuals. The concentration of MUC2 increased at 1 and 3 months after CAG surgery and decreased at 6 months; however, the MUC2 concentration decreased on the AMT group in all time point measurements. Interestingly, the MUC5AC concentration significantly increased at 1 month after AMT or CAG and then decreased at 3 and 6 months after surgery. Finally, an inverse correlation was found between both MUC2 and MUC5AC tear mucins concentration and the TBUT. Conclusions: These results suggest that pterygium excision via both CAG or AMT changes the concentrations of the tear mucins MUC2 and MUC5AC during the evaluated times, and these changes could affect tear film stability and clinical recovery after pterygium treatment. Translational Relevance: The tear film stability during pterygium excision was evaluated to determine adequate treatments.

Intravitreal Antiangiogenic Treatment for Diabetic Retinopathy: A Mexican Real-Life Scenario Experience.

The objective of this study was to analyze the effectiveness of two intravitreal antiangiogenic drugs, ranibizumab and aflibercept, in a Mexican population over a period of 5 years, evaluating the improvement in visual acuity (VA) and central retinal thickness (CRT) in a real-world scenario. This is a retrospective study with subjects diagnosed with diabetic retinopathy (DR), proliferative diabetic retinopathy (PDR), and diabetic macular edema (DME) receiving intravitreal injections of ranibizumab and/or aflibercept. In this study, we analyzed 588 eyes of 294 patients who received intravitreal antiangiogenic injections. The results showed an improvement regardless of antiangiogenic treatment or diagnosis in both VA and CRT. We found that both aflibercept and ranibizumab improved VA, while subjects with DME responded less to antiangiogenic treatment (p < 0.05), and that this difference did not correspond to the CRT measured by OCT. These results support evidence that intravitreal antiangiogenic medications are effective for ophthalmic complications of diabetes in our population; however, damage to visual structures is not reversed in most patients. And that the perception by the patient (VA) and that of the ophthalmologist (CRT) do not completely correlate in our study.

Perilipin 2-positive mononuclear phagocytes accumulate in the diabetic retina and promote PPARγ-dependent vasodegeneration.

Type 2 diabetes mellitus (T2DM), characterized by hyperglycemia and dyslipidemia, leads to nonproliferative diabetic retinopathy (NPDR). NPDR is associated with blood-retina barrier disruption, plasma exudates, microvascular degeneration, elevated inflammatory cytokine levels, and monocyte (Mo) infiltration. Whether and how the diabetes-associated changes in plasma lipid and carbohydrate levels modify Mo differentiation remains unknown. Here, we show that mononuclear phagocytes (MPs) in areas of vascular leakage in DR donor retinas expressed perilipin 2 (PLIN2), a marker of intracellular lipid load. Strong upregulation of PLIN2 was also observed when healthy donor Mos were treated with plasma from patients with T2DM or with palmitate concentrations typical of those found in T2DM plasma, but not under high-glucose conditions. PLIN2 expression correlated with the expression of other key genes involved in lipid metabolism (ACADVL, PDK4) and the DR biomarkers ANGPTL4 and CXCL8. Mechanistically, we show that lipid-exposed MPs induced capillary degeneration in ex vivo explants that was inhibited by pharmaceutical inhibition of PPARγ signaling. Our study reveals a mechanism linking dyslipidemia-induced MP polarization to the increased inflammatory cytokine levels and microvascular degeneration that characterize NPDR. This study provides comprehensive insights into the glycemia-independent activation of Mos in T2DM and identifies MP PPARγ as a target for inhibition of lipid-activated MPs in DR.

Risk Factors for Diabetic Retinopathy in Latin America (Mexico) and the World: A Systematic Review and Meta-Analysis.

Diabetic retinopathy (DR) is one of the main complications of diabetes, and the management of the main control parameters explains only an 11% reduction in the risk of progressing to DR, leaving 89% to be explained by other factors or correlations between the usual factors that are currently unknown. The objective of this systematic review and meta-analysis is to evaluate the similarities and differences between the possible risk factors for developing DR when comparing the world to Latin American populations. The search was performed first for Latin American (LA) populations and a second search for non-Latin American (Non-LA) populations. Using the PRISMA guidelines, five articles were found to be relevant for each of the groups. The patients who had elevated systolic blood pressure (SBP) developed DR more frequently than the patients without retinopathy (Z = 2.1, p = 0.03), an effect measured in the population at a global level (GL), behavior that becomes not significant when the LA and non-LA populations are grouped separately; relevant to this is that the diagnosis of hypertension (HBP) grouped globally and stratified does not present a risk factor for DR (Z = 0.79, p = 0.42). This indicates that SBP is a risk factor for the world population and that, by separating it into different regions, the omission could cause it not to be considered a possible risk factor. In conclusion, the relationship between the increase in DR associated with the risk factors present in different populations, the limited research conducted in Latin America, and the cultural, social, economic, and genetic differences makes for a complex condition, which reflects the necessity of researching in a more integrated way.

GK-1 effectively reduces angiogenesis and prevents T cell exhaustion in a breast cancer murine experimental model.

Breast cancer is the leading malignancy in women worldwide, both in terms of incidence and mortality. Triple-negative breast cancer (TNBC) is the type with the worst clinical outcomes and with fewer therapeutic options than other types of breast cancer. GK-1 is a peptide that in the experimental model of the metastatic 4T1 breast cancer has demonstrated anti-tumor and anti-metastatic properties. Herein, GK-1 (5 mg/kg, i.v.) weekly administrated not only decreases tumor growth and the number of lung macro-metastases but also lung and lymph nodes micro-metastases. Histological analysis reveals that GK-1 reduced 57% of the intra-tumor vascular areas, diminished the leukemoid reaction's progression, and the spleens' weight and length. A significant reduction in VEGF-C, SDF-1, angiopoietin-2, and endothelin-1 angiogenic factors was induced. Moreover, GK-1 prevents T cell exhaustion in the tumor-infiltrating lymphocytes (TILs) decreasing PD-1 expression. It also increased IFN-γ and granzyme-B expression and the cytotoxic activity of CD8+ TILs cells against tumor cells. All these features were found to be associated with a better antitumor response and prognosis. Altogether, these results reinforce the potential of GK-1 to improve the clinical outcome of triple-negative breast cancer immunotherapy. Translation research is ongoing towards its evaluation in humans.

Spontaneous Neutrophil Extracellular Traps Release Are Inflammatory Markers Associated with Hyperglycemia and Renal Failure on Diabetic Retinopathy.

Diabetic retinopathy (DR) is the major microvascular complication of diabetes and causes vitreous traction and intraretinal hemorrhages leading to retinal detachment and total blindness. The evolution of diabetes is related to exacerbating inflammation caused by hyperglycemia and activation of inflammatory cells. Neutrophils are cells able to release structures of extracellular DNA and proteolytic enzymes called extracellular traps (NETs), which are associated with the persistence of inflammation in chronic pathologies. The purpose of the study was to determine the usefulness of neutrophil traps as indicators of DR progression in patients with type 2 diabetes (T2DM). We performed a case-control study of seventy-four cases classified into five groups (non-proliferative DR, mild, moderate, severe, and proliferative) and fifteen healthy controls. We found correlations between NETs and a diagnostic time of T2DM (r = 0.42; p < 0.0001), fasting glucose (r = 0.29; p < 0.01), glycated hemoglobin (HbA1c) (r = 0.31; p < 0.01), estimated glomerular filtration rate (eGFR) (r = -0.29; p < 0.01), and plasma osmolarity (r = 0.25; p < 0.01). These results suggest that due to NETs being associated with clinical indicators, such as HbA1c and eGFR, and that NETs are also associated with DR, clinical indicators might be explained in part through an NET-mediated inflammation process.

Subconjunctival Sirolimus-Loaded Liposomes for the Treatment of Moderate-to-Severe Dry Eye Disease.

Purpose: To determine the effectiveness of subconjunctival application of a novel sirolimus liposomal formulation for the treatment of dry eye. Methods: A randomized, triple-blind, Phase II clinical trial. Thirty-eight eyes of 19 patients were included. Nine patients (18 eyes) assigned to the sham group (Sham) and 10 patients (20 eyes) to sirolimus-loaded liposomes group (Sirolimus). The treatment group received three doses of subconjunctival liposome-encapsulated sirolimus and the sham group received three doses of liposomal suspension without sirolimus. Subjective (Ocular Surface Disease Index, OSDI) and measured (corrected distance visual acuity, conjunctival hyperemia, tear osmolarity, Schirmer's test, corneal/conjunctival staining and matrix metalloproteinase-9) variables were measured. Results: Sirolimus-entrapped liposomes-treated group OSDI scores changed from 62.19 (± 6.07) to 37.8 (± 17.81) (p=0.0024), and conjunctival hyperemia from 2.0 (± 0.68) to 0.83 (± 0.61) (p<0.0001); Sham group with OSDI scores from 60.02 (± 14.2) to 36.02 (± 20.70) (p=0.01), and conjunctival hyperemia from 1.33 (± 0.68) to 0.94 (± 0.87) (p=0.048). All the other evaluated outcomes only showed significant differences in the sirolimus group: corneal/conjunctival staining score (p=0.0015), lipid layer interferometry (p=0.006), and inferior meibomian gland dropout (p=0.038). No local or systemic adverse effects regarding the medication itself were reported, and the administration route was well accepted. Conclusion: Our findings suggest that sub-conjunctival sirolimus-loaded liposomes are effective in reducing both signs and symptoms of dry eye in patients with poorly controlled moderate-to-severe DED, while avoiding other topical administration adverse effects. Further investigation with a larger sample size is required to determine long-term effects.

Seroprevalence of SARS-CoV-2 in Mexican Health Care Workers after Two Years of the Pandemic: The Picture of an Ophthalmic Medical Centre.

OBJECTIVE: In this study, we investigated the impact of the SARS-CoV-2 vaccination on seroprevalence in a cohort of healthcare workers (HCW) at an ophthalmic medical center. METHODS: IgG antibodies against the N, S1, and S2 antigens of SARS-CoV-2 as well as their serum neutralizing activity were determined. RESULTS: In the present study, we observed that 98.4% of HCW were seropositive for S1/S2 proteins of SARS-CoV-2 due to the national vaccination program. Interestingly, 78.4% of the participants had anti-N protein antibodies, suggesting previous COVID-19 infection. We also evaluated the neutralizing antibodies and found that the mean value was high (90.7%). CONCLUSION: These results indicate that our HCWs cohort presented a robust hybrid humoral response owing to the massive national vaccination program and natural infections.

Cytokine profile of human limbal myofibroblasts: Key players in corneal antiviral response.

BACKGROUND: Corneal transparency may be compromised by viral infections causing corneal scarring, edema, and neovascularization. Ocular injury results from collateral damage induced by exacerbated immune response in corneal stroma. Myofibroblasts play a key role in this process by producing a disorganized extracellular matrix and inflammatory mediators. However, the immune response profile of myofibroblasts during viral infections is still under study. The aim of this work was to analyze the cytokine profile of human limbal myfibroblasts (HLMs) stimulated with the double-stranded RNA analog polyinosinic:polycytidylic acid (poly I:C) and to identify their signaling pathways. METHODS: HLMs were isolated from cadaveric sclera-corneal rims and stimulated with poly I:C (10 µg/ml) for 12 h. The secretion of 36 cytokines was measured using the Human Cytokine Array Panel A. The secretion of IFN-ß was quantified by ELISA. The expression of pattern recognition receptors (PRRs) such as TLR3, RIG-1 and MDA5 were analyzed by western blot assays. Furthermore, translocation of the nuclear factors NF-κB, IRF3, and IRF7 was assessed by fluorescence staining. In addition, the differentially expressed cytokines were analyzed using the Core Analysis Tool of the Ingenuity Pathway Analysis IPA software. RESULTS: HLMs stimulated with poly I:C increased (fold change > 2) the secretion of G-CSF, sTREM-1, CXCL1, CCL1, CXCL8, CXCL10, CXCL11, CCL2, CCL5, IL-13, IL-6, IL-1ra, and IFN-ß compared with HLMs under basal conditions. Poly I:C stimulation also induced the expression of RIG-1 (p < 0.001), but the expression of TLR3 and MDA5 was unmodified. Finally, HLMs increased nuclear translocation of NF-κB, IRF3, and IRF7 after poly I:C stimulation. Bioinformatic analysis identified canonical signaling pathways associated with cell adhesion and diapedesis, chemokine signaling, and activation of IRFs by cytosolic pattern recognition receptors. CONCLUSIONS: These results demonstrate that HLMs secrete cytokines involved in immune cell activation and chemotaxis. The data suggest a key role for HLMs during viral infections in cornea and extend our knowledge about the signaling pathways they trigger.

Lumican Extraction from Amniotic Membrane and Determination of its Storage Temperature.

Lumican is a small leucine-rich proteoglycan in the human amniotic membrane (AM) that promotes corneal epithelialization and the organization of collagen fibers, maintaining corneal transparency. In the present work, a method for protein extraction from AM to obtain lumican is proposed. Additionally, the stability of lumican in the AM extract (AME) stored at different temperatures and time periods is evaluated. 100 mg of AM were thawed and mechanical de-epithelialized. The de-epithelialized AM was frozen and crushed until a fine powder was obtained, which was solubilized with 2.5 mL of saline buffer with protease inhibitors and centrifuged for protein extraction. The supernatant was collected and stored at -20 °C, 4 °C, and room temperature (RT) for 6, 12, 20, and 32 days. Afterward, lumican was quantified in each AME. This technique allows an accessible and acquirable protocol for lumican extraction from AM. Lumican concentration was affected by storage time and temperature conditions. Lumican in the AME of 12 days stored at -20 °C and 4 °C was significantly higher than other AME. This lumican extraction could be useful for developing treatments and pharmaceutical solutions. Further studies are needed to determine the uses of AME lumican in re-epithelialization and wound healing process.

Human Amniotic Membrane Mesenchymal Stem Cell-Synthesized PGE2 Exerts an Immunomodulatory Effect on Neutrophil Extracellular Trap in a PAD-4-Dependent Pathway through EP2 and EP4.

Human amniotic membrane mesenchymal stem cells (hAM-MSC) secrete a myriad of components with immunosuppressive activities. In the present research, we aimed to describe the effect of prostaglandin E2 (PGE2) secreted by hAM-MSCs on neutrophil extracellular trap (NET) release and to characterize the role of its receptors (EP2/EP4) in PAD-4 and NFκB activity in neutrophils. Human peripheral blood neutrophils were ionomycin-stimulated in the presence of hAM-MSC conditioned medium (CM) treated or not with the selective PGE2 inhibitor MF-63, PGE2, EP2/EP4 agonists, and the selective PAD-4 inhibitor GSK-484. NET release, PAD-4, and NFκB activation were analyzed. Ionomycin induced NET release, which was inhibited in the presence of hAM-MSC-CM, while CM from hAM-MSCs treated with MF-63 prevented NET release inhibition. PGE2 and EP2/EP4 agonists, and GSK-484 inhibited NET release. EP2/EP4 agonists and GSK-484 inhibited H3-citrullination but did not affect PAD-4 protein expression. Finally, PGE2 and EP2/EP4 agonists and GSK-484 increased NFκB phosphorylation. Taken together, these results suggest that hAM-MSC exert their immunomodulatory activities through PGE2, inhibiting NET release in a PAD-4-dependent pathway. This research proposes a new mechanism by which hAM-MSC exert their activities when modulating the innate immune response and inhibiting NET release.

Reliability, repeatability, and accordance between three different corneal diagnostic imaging devices for evaluating the ocular surface.

Purpose: To evaluate repeatability, reproducibility, and accordance between ocular surface measurements within three different imaging devices. Methods: We performed an observational study on 66 healthy eyes. Tear meniscus height, non-invasive tear break-up time (NITBUT) and meibography were measured using three corneal imaging devices: Keratograph 5M (Oculus, Wetzlar, Germany), Antares (Lumenis, Sidney, Australia), and LacryDiag (Quantel Medical, Cournon d'Auvergne, France). One-way ANOVAs with post hoc analyses were used to calculate accordance between the tear meniscus and NITBUT. Reproducibility was assessed through coefficients of variation and repeatability with intraclass correlation coefficients (ICC). Reliability of meibography classification was analyzed by calculating Fleiss' Kappa Index and presented in Venn diagrams. Results: Coefficients of variation were high and differed greatly depending on the device and measurement. ICCs showed moderate reliability of NITBUT and tear meniscus height measurements. We observed discordance between measurements of tear meniscus height between the three devices, F2, 195 = 15.24, p < 0.01. Measurements performed with Antares were higher; 0.365 ± 0.0851, than those with Keratograph 5M and LacryDiag; 0.293 ± 0.0790 and 0.306 ± 0.0731. NITBUT also showed discordance between devices, F2, 111 = 13.152, p < 0.01. Measurements performed with LacryDiag were lower (10.4 ± 1.82) compared to those of Keratograph 5M (12.6 ± 4.01) and Antares (12.6 ± 4.21). Fleiss' Kappa showed a value of -0.00487 for upper lid and 0.128 for inferior lid Meibography classification, suggesting discrete to poor agreement between measurements. Conclusion: Depending on the device used and parameter analyzed, measurements varied between each other, showing a difference in image processing.

Extracellular traps involved in invertebrate immune mechanisms.

The invertebrate immune system possesses a mechanism named extracellular traps (ETs), it has been identified that this mechanism immobilizes and kills pathogens. ETs formation induces modification of histones, chromatin decondensation, and mixes with granule molecules, releasing them into the extracellular space as a defense mechanism. In the present review, we provide an overview on the identification of triggering stimuli such as pathogens, PAMPs, DAMPs, and chemical stimuli, discuss the participation of potential signaling pathways involving MAPK, PI3K, PKC, and ERK molecules that lead to NADPH oxidase or mitochondrial ROS production, and explore the potential relationship with several proteins such as myeloperoxidase, heat sock proteins, peroxinectin, elastase, and apolipoproteins. Furthermore, we also discuss the association of ETs with other immune mechanisms that could collaborate in the elimination of pathogens.

SARS-CoV-2 Seroprevalence among the Health Care Staff of an Ophthalmological Reference Centre, a Cross Sectional Study.

PURPOSE: During the COVID-19 pandemic, healthcare workers (HCWs) are at a considerable risk of being infected with SARS-CoV-2; among them, HCWs from ophthalmology departments are more prone to develop severe symptoms. In Mexico City, the prevalence of SARS-CoV-2 infection among HCWs is 30%. The present work aims to describe the seroprevalence among HCWs at an Ophthalmological Reference Centre in Mexico City. METHODS: A self-report questionnaire, RT-PCR test and detection of serum IgG/IgM antibodies against SARS-CoV-2 were performed among HCWs at the Institute of Ophthalmology "Conde de Valenciana". RESULTS: A total of 169 HCWs participated in the study. None of the participants declared severe symptoms, and only 15% showed three or more symptoms. The results showed that 32% of the participants were RT-PCR+ (54/169), and 20% (35/169) presented IgG antibodies against SARS-CoV-2. Thirteen percent of the RT-PCR+ subjects were IgG positive, and 7.6% of the RT-PCR- participants were IgG positive. The presence of three or more symptoms correlated with the presence of IgG antibodies, as well as Ct values of < 32 (p < 0,05). CONCLUSION: Most of the HCW cohort showed mild symptoms, and 69% of the RT-PCR+ participants did not show IgG antibodies against SARS-CoV-2. Seroprevalence was significantly associated with the presentation of COVID-19-associated symptoms.

AS1411 Nucleolin-Specific Binding Aptamers Reduce Pathological Angiogenesis through Inhibition of Nucleolin Phosphorylation.

Proliferative retinopathies produces an irreversible type of blindness affecting working age and pediatric population of industrialized countries. Despite the good results of anti-VEGF therapy, intraocular and systemic complications are often associated after its intravitreal use, hence novel therapeutic approaches are needed. The aim of the present study is to test the effect of the AS1411, an antiangiogenic nucleolin-binding aptamer, using in vivo, ex vivo and in vitro models of angiogenesis and propose a mechanistic insight. Our results showed that AS1411 significantly inhibited retinal neovascularization in the oxygen induced retinopathy (OIR) in vivo model, as well as inhibited branch formation in the rat aortic ex vivo assay, and, significantly reduced proliferation, cell migration and tube formation in the HUVEC in vitro model. Importantly, phosphorylated NCL protein was significantly abolished in HUVEC in the presence of AS1411 without affecting NFκB phosphorylation and -21 and 221-angiomiRs, suggesting that the antiangiogenic properties of this molecule are partially mediated by a down regulation in NCL phosphorylation. In sum, this new research further supports the NCL role in the molecular etiology of pathological angiogenesis and identifies AS1411 as a novel anti-angiogenic treatment.

Amniotic membrane conditioned medium (AMCM) reduces inflammatory response on human limbal myofibroblast, and the potential role of lumican.

Purpose: Viral infections such as herpetic keratitis (HSK) activate the innate immune response in the cornea triggering opacity and loss of vision. This condition is performed mainly by myofibroblasts that exacerbate secretion of inflammatory cytokines. Amniotic membrane transplantation (AMT) reduces ocular opacity and scarring inhibiting secretion of inflammatory cytokines and proliferation of myofibroblasts. We previously reported that the amniotic membrane (AM) favors an anti-inflammatory microenvironment inhibiting the secretion of inflammatory cytokines, expression of innate immune receptors, and translocation of nuclear NF-κB on human limbal myofibroblasts (HLMs). The aim of the present study was to determine whether the soluble factors of the AM decrease the immune response of HLMs stimulated with polyinosinic-polycytidylic acid sodium salt (poly I:C). Methods: The AM was incubated in Dulbecco's modified eagle medium (DMEM)/F12, and the supernatant was collected to obtain amniotic membrane conditioned medium (AMCM). HLMs were isolated from cadaveric sclera-corneal rims. HLMs were cultured in DMEM/F12 or AMCM and stimulated or not with poly I:C (10 µg/ml) for 12 h to analyze synthesis of CCL2, CCL5, CXCL10, MDA5, RIG-1, and TLR3 or for 2 h to analyze translocation of nuclear NF-kB, IRF3, and IRF7. The proteins contained on AMCM were analyzed by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and the acquired peptide ions were analyzed with the Mascot program using both National Center for Biotechnology Information (NCBI) and expressed sequence tag (EST) databases. Results: AMCM downregulated the mRNA levels of CCL2, CCL5, CXCL10, MDA5, RIG-1, and TLR3. In addition, AMCM decreased secretion of CCL2, CCL5, and CXCL10 and translocation of nuclear NF-κB. Interestingly, AMCM increased translocation of nuclear IRF3 and synthesis and secretion of type I IFN-ß. We also identified small leucine-rich proteoglycan lumican in the AMCM. The administration of rh-lumican to poly I:C-stimulated HLMs reduced the mRNA levels of CCL2, CCL5, and CXCL10. Conclusions: These results suggest that the AM can trigger an anti-inflammatory response on HLMs through soluble factors, and that lumican could play an important role in these effects.

Can Human Oral Mucosa Stem Cells Differentiate to Corneal Epithelia?

Human oral mucosa stem cells (hOMSCs) arise from the neural crest, they can self-renew, proliferate, and differentiate to several cell lines and could represent a good source for application in tissue engineering. Because of their anatomical location, hOMSCs are easy to isolate, have multilineage differentiation capacity and express embryonic stem cells markers such as-Sox2, Oct3/4 and Nanog. We have used SHEM (supplemented hormonal epithelial medium) media and cultured hOMSCs over human amniotic membrane and determined the cell's capacity to differentiate to an epithelial-like phenotype and to express corneal specific epithelial markers-CK3, CK12, CK19, Pan-cadherin and E-cadherin. Our results showed that hOMSCs possess the capacity to attach to the amniotic membrane and express CK3, CK19, Pan-Cadherin and E-Cadherin without induction with SHEM media and expressed CK12 or changed the expression pattern of E-Cadherin to a punctual-like feature when treated with SHEM media. The results observed in this study show that hOMSCs possess the potential to differentiate toward epithelial cells. In conclusion, our results revealed that hOMSCs readily express markers for corneal determination and could provide the ophthalmology field with a therapeutic alternative for tissue engineering to achieve corneal replacement when compared with other techniques. Nevertheless, further studies are needed to develop a predictable therapeutic alternative for cornea replacement.

Future Perspectives of Therapeutic, Diagnostic and Prognostic Aptamers in Eye Pathological Angiogenesis.

Aptamers are single-stranded DNA or RNA oligonucleotides that are currently used in clinical trials due to their selectivity and specificity to bind small molecules such as proteins, peptides, viral particles, vitamins, metal ions and even whole cells. Aptamers are highly specific to their targets, they are smaller than antibodies and fragment antibodies, they can be easily conjugated to multiple surfaces and ions and controllable post-production modifications can be performed. Aptamers have been therapeutically used for age-related macular degeneration, cancer, thrombosis and inflammatory diseases. The aim of this review is to highlight the therapeutic, diagnostic and prognostic possibilities associated with aptamers, focusing on eye pathological angiogenesis.

Pro-inflammatory cytokine profile is present in the serum of Mexican patients with different stages of diabetic retinopathy secondary to type 2 diabetes.

AIM: It's been reported that pro-inflammatory cytokines are elevated in patients with diabetic retinopathy (DR); this may contribute to the pathophysiology of the disease. The aim of this study is to measure the concentration of various inflammatory cytokines from the main CD4+ T helper inflammatory responses in blood serum from Mexican patients with DR in different stages using cytometric bead array (CBA) technology and correlate them with the presence and severity of DR in order to find possible DR biomarkers that serve as diagnostic or therapeutic predictors. METHODS: 64 subjects were included in the study, 16 in the control group, 16 in the type 2 diabetes mellitus no DR (NDR) group, 16 in the non-proliferative DR (NPDR) group and 16 in the proliferative DR (PDR) group. Cytokine concentrations of interleukin (IL) 1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17A, tumour necrosis factor alpha (TNFα) and interferon-gamma in serum samples were measured using Human Inflammatory and TH1/TH2/TH17 CBA Kit. RESULTS: IL-6, IL-12, IL-17a and TNFα were significantly higher in the patients with DR compared with the control group. The PDR group showed a slightly lower concentration of serum cytokines IL-6, IL-12 and IL-17a. TNFα showed a higher concentration compared with healthy controls, NDR and NPDR subjects. We also found a positive statistical correlation between the presence and severity of DR with the clinical parameters haemoglobin A1c, body mass index and serum creatinine and the concentration of serum cytokines IL-6 and TNFα. CONCLUSION: Our findings suggest that patients with diabetes and DR have a stronger chronic inflammatory profile compared with non-diabetic subjects.