Donor Corneal Endothelial Cell Maturity and Its Impact on Graft Survival in Glaucoma Patients Undergoing Corneal Transplantation

PURPOSE

To examine corneal graft survival via corneal endothelial cell density (ECD) and corneal endothelial cell loss (ECL) at 5 years post-transplantation in the eyes of patients with and without a history of undergoing glaucoma surgery according to the maturity of the donor corneal endothelial cells.

DESIGN

Prospective cohort study.

METHODS

This prospective cohort study included 17 patients with glaucoma and 51 patients without glaucoma who underwent Descemet's stripping automated endothelial keratoplasty or penetrating keratoplasty at the Baptist Eye Institute, Kyoto, Japan, between October 2014 and October 2016. Human corneal endothelial cells were cultured from residual peripheral donor cornea tissue, and the maturity of the cells was evaluated by cell surface markers (ie, CD166+, CD44-/dull, CD24-, and CD105-) using fluorescence-activated cell sorting. Kaplan-Meier analysis or the chi-square test was used to assess the rate of successful corneal graft survival post-transplantation.

RESULTS

At 36 months postoperatively, the mean ECD and ECL in the glaucoma-bleb eyes were 1197 ± 352 cells/mm2 and 55.5% ± 13.9% in the high-maturity group and 853 ± 430 cells/mm2 and 67.7% ± 18.1% in the low-maturity group, respectively. Kaplan-Meier analysis revealed that at 5 years postoperatively, the overall rate of survival was 45%, that is, 100% in the high-maturity group and 25% in the low-maturity group (P < .05).

CONCLUSIONS

The findings in this prospective cohort study revealed that the use of donor corneal grafts containing mature-differentiated corneal endothelial cells could maintain the survival of the transplanted graft for a long-term period, even in patients with a history of undergoing glaucoma surgery.

Cellular Interplay Through Extracellular Vesicle miR-184 Alleviates Corneal Endothelium Degeneration

OBJECTIVE

The objective of the study was to reveal the presence of cellular interplay through extracellular vesicle (EV) microRNAs (miRs), to dampen the vicious cycle to degenerate human corneal endothelium (HCE) tissues.

DESIGN

Prospective, comparative, observational study.

METHODS

The miR levels in neonate-derived corneal tissues, in the aqueous humor (AqH) of bullous keratoplasty and cataract patients, as well as in the culture supernatant (CS) and EV of cultured human corneal endothelial cells (hCECs), were determined using 3D-Gene human miR chips and then validated using the real-time polymerase chain reaction. The extracellularly released miRs were profiled after the forced downregulation of cellular miR-34a, either by an miR-34a inhibitor or exposure to H₂O₂. The senescence-associated secretory phenotypes and mitochondrial membrane potential (MMP) were assessed to determine the functional features of the released miRs.

MAIN OUTCOME MEASURES

Identification of functional miRs attenuating HCE degeneration.

RESULTS

The miRs in AqH were classified into 2 groups: expression in 1 group was significantly reduced in neonate-derived tissues, whereas that in the other group remained almost constant, independent of aging. The miR-34a and -29 families were typical in the former group, whereas miR-184 and -24-3p were typical in the latter. Additionally, a larger amount of the latter miRs was detected in AqH compared with those of the former miRs. There was also a greater abundance of miR-184 and -24-3p in hCECs, EV, and CS in fully mature CD44^-/dull hCEC, leading to sufficient clinical tissue regenerative capacity in cell injection therapy. The repression of cellular miR-34a, either due to miR-34a inhibitors or exposure to oxidative stress, unexpectedly resulted in the elevated release of miR-184 and -24-3p. Secretions of VEGF, interleukin 6, monocyte chemotactic protein-1, and MMP were all repressed in both mature CD44^-/dull and degenerated CD44⁺⁺⁺ hCEC, transfected with an miR-184 mimic.

CONCLUSIONS

The elevated release of miR-184 into AqH may constitute cellular interplay that prevents the aggravation of HCE degeneration induced by oxidative stress, thereby sustaining tissue homeostasis in HCE.

The Biologic Character of Donor Corneal Endothelial Cells Influences Endothelial Cell Density Post Successful Corneal Transplantation

Purpose

Corneal endothelial cell density (ECD) gradually decreases after corneal transplantation by unknown biologic, biophysical, or immunologic mechanism. Our purpose was to assess the association between donor corneal endothelial cell (CEC) maturity in culture and postoperative endothelial cell loss (ECL) after successful corneal transplantation.

Design

Prospective cohort study.

Participants

This cohort study was conducted at Baptist Eye Institute, Kyoto, Japan, between October 2014 and October 2016. It included 68 patients with a 36-month follow-up period who had undergone successful Descemet stripping automated endothelial keratoplasty (DSAEK) or penetrating keratoplasty.

Methods

Human CECs (HCECs) from remaining peripheral donor corneas were cultured and evaluated for maturity by surface markers (CD166⁺, CD44^-/dull, CD24^-, and CD105^-) using fluorescence-activated cell sorting. Postoperative ECD was assessed according to the mature-differentiated HCEC contents: high-maturity group: > 70%, middle-maturity group: 10% to 70%, low-maturity group: < 10%. The successful rate of ECD maintained at 1500 cells/mm² at 36 months postoperative was analyzed using the log-rank test.

Main Outcome Measures

Endothelial cell density and ECL at 36 months postoperative.

Results

The 68 included patients (mean [standard deviation] age 68.1 [13.6] years, 47.1% women, 52.9% DSAEK). The high, middle, and low-maturity groups included 17, 32, and 19 eyes, respectively. At 36 months postoperative, the mean (standard deviation) ECD significantly decreased to 911 (388) cells/mm² by 66% in the low-maturity group, compared with 1604 (436) by 40% and 1424 (613) cells/mm² by 50% in the high and middle-maturity groups (P < 0.001 and P = 0.007, respectively) and the low-maturity group significantly failed to maintain ECD at 1500 cells/mm² at 36 months postoperative (P < 0.001). Additional ECD analysis for patients who underwent DSAEK alone displayed a significant failure to maintain ECD at 1500 cells/mm² at 36 months postoperative (P < 0.001).

Conclusions

The high content of mature-differentiated HCECs expressed in culture by the donor peripheral cornea was coincident with low ECL, suggesting that a high-maturity CEC content predicts long-term graft survival. Understanding the molecular mechanism for maintaining HCEC maturity could elucidate the mechanism of ECL after corneal transplantation and aid in developing effective interventions.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Repressed miR-34a Expression Dictates the Cell Fate to Corneal Endothelium Failure

Purpose

To reveal the mechanism triggering the functional disparity between degenerated and non-degenerated corneal endothelium cells in the water efflux from corneal stroma to the anterior chamber.

Methods

The varied levels of the microRNA (miR)-34, miR-378, and miR-146 family in human corneal endothelium and cultured cells thereof were investigated using 3D-Gene Human miRNA Oligo Chips. Concomitantly, CD44, p53, c-Myc, matrix metalloprotease (MMP)-2 expression, and Ras homolog gene family member A (Rho A) activity was correlated to the expression intensities of these microRNAs, partly complemented with their altered expression levels with the transfection of the corresponding mimics and inhibitors. The levels of miRs were further associated with intracellular pH (pHi) and mitochondrial energy homeostasis.

Results

P53-inducible miR-34a/b repressed CD44 expression, and CD44 was repressed with the elevated c-Myc. The repressed miR-34a activated the CD44 downstream factors Rho A and MMP-2. MiR-34a mimics downregulated pHi, inducing the skewing of mitochondrial respiration to oxidative phosphorylation. The oxidative stress (H₂O₂) induced on human corneal endothelial cells, which repressed miR-34a/b expression, may account for the impaired signaling cascade to mitochondrial metabolic homeostasis necessary for an efficient water efflux from the corneal stroma.

Conclusions

The upregulated expression of CD44, through repressed miR-34a/b by reactive oxygen species and elevated c-Myc by oxidative stress, may impair mitochondrial metabolic homeostasis, leading to human corneal endothelial failure.

Development of assembled microchannel resonator as an alternative fabrication method of a microchannel resonator for mass sensing in flowing liquid

We propose an alternate fabrication technique of microchannel resonators based on an assembly method of three separate parts to form a microchannel resonator on a chip. The capability of the assembled microchannel resonator to detect mass is confirmed by injecting two liquids with different densities. The experimental and theoretical values of the resonator frequency shift are in agreement with each other, which confirms the consistency of the device. The noise level of the device is estimated from the Allan variance plot, so the minimum detectable mass of 230 fg after 16 s of operation is expected. By considering the time of the practical application of 1 ms, it is found that a detectable mass of around 8.51 pg is estimated, which is applicable for detecting flowing microparticles. The sub-pico to a few picogram levels of detection will be applicable for the mass analysis of flowing microparticles such as single cells and will be greatly beneficial for many fields such as chemistry, medicine, biology, and single-cell analysis.

Clinical usefulness of Lipoprotein(a) for the prevalence and severity of peripheral artery disease among patients with acute coronary syndrome

Background

Lipoprotein(a) [LP(a)] is known to be a robust lipid marker associated with cardiovascular events. Though coronary artery disease and peripheral artery disease (PAD) are often coexist, little is known about the relationship between LP(a) and PAD among patients with acute coronary syndrome (ACS).

Purpose

The purpose of this study is to examine if LP(a) is of predictive value for PAD among ACS patients in Japanese population.

Methods

Of consecutive 238 ACS patient who received successful primary PCI, a total of 175 patients were enrolled in the current study. We excluded the patients who received hemodialysis (n=10), required multidisciplinary treatment (n=36) and incomplete data (n=17). PAD was diagnosed as ankle brachial index &lt;0.9. Multiple lipid biomarkers [LP(a), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), malondialdehyde-modified LDL (MDA-LDL), docosahexaenoic acid and arachidonic acid] were compared between patients with PAD (n=21) and without PAD (n=154). Further, multivariable logistic regression models were used to assess if LP(a) was associated with PAD. In addition, serum LP(a) level were compared between 3 groups according to pattern of PAD [none (n=154), unilateral (n=10) and bilateral PAD (n=11), respectively].

Results

Compared to patients without PAD, those with PAD were older (74.4 vs. 65.4 years, p=0.003), and had a higher prevalence of chronic kidney disease (CKD) (61.9% vs. 20.1%, p&lt;0.001), diabetes mellitus (DM) (66.7% vs. 27.3%, p&lt;0.001). Serum LP(a) level was significantly higher in patients with PAD (36.4 vs. 18.5 mg/dl, p&lt;0.001), whereas LDL-C and MDA-LDL were significantly lower in PAD (92.0 vs. 109.5 mg/dl, p=0.015 and 98.6 vs. 119.5 mg/dl, p=0.046, respectively). After adjusting for LDL-C and MDA-LDL, LP(a) &gt;30 mg/dl was independently associated with a presence of PAD (OR 5.67, 95% CI 2.09–15.4, p=0.0006). When adjusting for CKD and DM in a different model, LP(a) &gt;30 mg/dl was similarly associated with PAD (OR 4.98, 95% CI 1.66–14.9, p=0.004). Serum LP(a) levels were significantly higher in bilateral PAD group compared to none PAD group (Figure).

Conclusion

LP(a) was a useful lipid biomarker for the prevalence and severity of PAD among patients with ACS in Japanese population.

Funding Acknowledgement

Type of funding source: None

Metabolites Interrogation in Cell Fate Decision of Cultured Human Corneal Endothelial Cells

Purpose

Aiming to clarify the metabolic interrogation in cell fate decision of cultured human corneal endothelial cells (cHCECs).

Methods

To analyze the metabolites in the culture supernatants (CS), 34 metabolome measurements were carried out for mature differentiated and a variety of cHCECs with cell state transition through a facility service. Integrated proteomics research for cell lysates by liquid chromatography−tandem mass spectrometry (LC-MS/MS) was performed for 3 aliquots of each high-quality or low-quality cHCEC subpopulations (SP). The investigations for the focused genes involved in cHCEC metabolism were performed by using DAVID and its options “KEGG_PATHWAY.”

Results

The clusters of metabolites coincided well with the distinct content of CD44−/+ SPs. Both secreted pyruvic acid and lactic acid in the CS were negatively correlated with the content of high-quality SPs. Lactic acid and pyruvic acid in the CS exhibited the positive correlation with that of Ile, Leu, and Ser, whereas the negative correlation was with glutamine. Platelet-derived growth factor-ββ in the CS negatively correlated with lactic acid in CS, indicating indirectly the positive correlation with the content of CD44−/+ SPs. Upregulated glycolytic enzymes and influx of glutamine to the tricarboxylic acid cycle may be linked with a metabolic rewiring converting oxidative metabolism in mature differentiated CD44−/+SPs into a glycolytic flux-dependent state in immature SPs with cell state transition.

Conclusions

The findings suggest that the cell fate decision of cHCECs may be dictated at least partly through metabolic rewiring.

P5623Plaque characteristics, slow flow during percutaneous coronary intervention, and clinical outcomes of irregular protrusion by optical coherence tomography

Introduction

In pathological studies, penetration of the lipid core into the stent strut is associated with neointimal growth and stent thrombosis. Irregular protrusion on optical coherence tomography (OCT) is associated with clinical events and target lesion revascularization. However, there are few reports about the relationship among irregular protrusion, plaque characteristics, and slow flow during percutaneous coronary intervention. We investigated clinical and procedure characteristics, plaque characteristics, slow flow after stent implantation, and clinical outcomes with irregular protrusion by using OCT.

Methods

Eighty-four lesions in 76 patients undergoing OCT before percutaneous coronary intervention were evaluated. Irregular protrusion was defined as protrusion of material with an irregular surface into the lumen between stent struts with a maximum height of ≥100 μm. Major adverse clinical outcomes were defined as death, acute myocardial infarction, acute coronary syndrome, or target lesion revascularization.

Results

Lesions with irregular protrusion were found in 56% (47/84). Compared with lesions without irregular protrusion, those with irregular protrusion had significantly higher low-density lipoprotein cholesterol (LDL-C) levels (108±31 mg/dL vs. 95±25 mg/dL, P=0.044); a tendency toward decreased use of statins (44% [19/43] vs. 67% [22/33], P=0.065); significantly larger reference vessel diameter (3.12±0.53 mm vs. 2.74±0.63 mm, P=0.004); significantly larger stent diameter (3.23±0.43 mm vs. 3.00±0.49 mm, P=0.025); a tendency toward longer total stent length (29.3±14.2 mm vs. 23.7±11.4 mm, P=0.056); significantly larger maximum balloon diameter (3.56±0.55 mm vs. 3.22±0.63 mm, P=0.010); significantly higher incidence of slow flow after stent implantation (38% [18/47] vs. 11% [4/37], P=0.006); significantly higher ΔTIMI flow from pre-stenting to post-stenting (0.4±0.6 vs. 0.1±0.3, P=0.009); significantly higher incidence of lipid-rich plaque (70% [33/47] vs. 35% [13/37], P=0.002); thin-cap fibroatheromas (TCFAs: 49% [23/47] vs. 5% [2/37], P<0.001); plaque rupture (40% [19/47] vs. 16% [6/37], P=0.018); macrophage accumulation (51% [24/47] vs. 24% [9/37], P=0.015); internal running vasa vasorum (51% [24/47] vs. 11% [4/37], P<0.001); thrombus (32% [15/47] vs. 3% [1/37], P<0.001); and a tendency higher incidence of one-year adverse clinical outcomes (12% [5/43] vs. 0% [0/33], P=0.075: log rank). The multivariable analysis showed that TCFA was an independent predictor of irregular protrusion (odds ratio 9.00, 95% CI 1.32–61.36, P=0.025).

Conclusions

Irregular protrusion on OCT was associated with high plaque vulnerability, higher LDL-C, less frequent use of statin, larger vessel diameter, longer total stent length, slow flow after stent implantation, and one-year adverse clinical outcomes.

Microwave oscillator using piezoelectric thin-film resonator aiming for ultraminiaturization of atomic clock

We developed a microwave oscillator and a micro electromechanical systems-based rubidium cell for the miniaturization of atomic clocks. A thin-film bulk acoustic resonator (FBAR) having a resonant frequency of the fundamental mode in the 3.5 GHz band was employed instead of a crystal resonator. It delivers a clock transition frequency of Rb atoms of 3.417 GHz without the need for a complicated frequency multiplication using a phase-locked loop. This topology considerably reduces the system scale and power consumption. For downsizing the atomic clock system toward the chip level as well as mass production, a microfabricated gas cell containing Rb and N₂ gases was also developed. These microcomponents were incorporated into an atomic clock test bench, resulting in a clock operation with a short-term frequency instability of 2.1 × 10^-11 at 1 s. To the best of our knowledge, this is the first report of a coherent population trapping clock operation using an FBAR-based microwave oscillator as well as a microfabricated gas cell.

Distinct Aqueous Humour Cytokine Profiles of Patients with Pachychoroid Neovasculopathy and Neovascular Age-related Macular Degeneration

This study investigated the pathophysiological features of pachychoroid neovasculopathy (PNV) and neovascular age-related macular degeneration (nAMD) by analysing and comparing cytokine profiles in aqueous humour (AH) collected from 18 PNV, 18 nAMD and 11 control patients. Responses to intravitreal injection of aflibercept were also analysed in the PNV and nAMD groups. In the PNV group, vascular endothelial growth factor (VEGF)-A was significantly lower than in the nAMD group (p = 0.03) but was almost identical to that in the control group (p = 0.86). The nAMD group showed positive correlations between interleukin (IL)-6 and IL-8 (r = 0.78, p < 0.001), IL-6 and monocyte chemoattractant protein (MCP)-1 (r = 0.68, p = 0.002) and IL-8 and MCP-1 (r = 0.68, p = 0.002). In the nAMD group, eyes with dry maculae one month after the first aflibercept injection showed significantly lower VEGF-A and placental growth factor (PlGF) at baseline than those with wet maculae (p = 0.02 for both). However, there was no significant difference between dry and wet maculae in the PNV group. The results suggest that angiogenic factors and proinflammatory cytokines may play the distinct roles in the pathogenesis of PNV and nAMD.

Role of the Apparent Diffusion Coefficient as a Predictor of Tumor Progression in Patients with Chordoma

BACKGROUND AND PURPOSE

Diffusion-weighted imaging may aid in distinguishing aggressive chordoma from nonaggressive chordoma. This study explores the prognostic role of the apparent diffusion coefficient in chordomas.

MATERIALS AND METHODS

Sixteen patients with residual or recurrent chordoma were divided postoperatively into those with an aggressive tumor, defined as a growing tumor having a doubling time of <1 year, and those with a nonaggressive tumor on follow-up MR images. The ability of the ADC to predict an aggressive tumor phenotype was investigated by receiver operating characteristic analysis. The prognostic role of ADC was assessed using a Kaplan-Meier curve with a log-rank test.

RESULTS

Seven patients died during a median follow-up of 48 months (range, 4-126 months). Five of these 7 patients were in the aggressive tumor group, and 2 were in the nonaggressive tumor group. The mean ADC was significantly lower in the aggressive tumor group than in the nonaggressive tumor group (P = .002). Receiver operating characteristic analysis showed that a cutoff ADC value of 1.494 × 10^-3 × mm²/s could be used to diagnose aggressive tumors with an area under the curve of 0.983 (95% CI, 0.911-1.000), a sensitivity of 1.000 (95% CI, 0.541-1.000), and a specificity of 0.900 (95% CI, 0.555-0.998). Furthermore, a cutoff ADC of ≤1.494 × 10^-3 × mm²/s was associated with a significantly worse prognosis (P = .006).

CONCLUSIONS

Lower ADC values could predict tumor progression in postoperative chordomas.

Injection of Cultured Cells with a ROCK Inhibitor for Bullous Keratopathy

BACKGROUND

Corneal endothelial cell (CEC) disorders, such as Fuchs's endothelial corneal dystrophy, induce abnormal corneal hydration and result in corneal haziness and vision loss known as bullous keratopathy. We investigated whether injection of cultured human CECs supplemented with a rho-associated protein kinase (ROCK) inhibitor into the anterior chamber could increase CEC density.

METHODS

We performed an uncontrolled, single-group study involving 11 persons who had received a diagnosis of bullous keratopathy and had no detectable CECs. Human CECs were cultured from a donor cornea; a total of 1×10⁶ passaged cells were supplemented with a ROCK inhibitor (final volume, 300 μl) and injected into the anterior chamber of the eye that was selected for treatment. After the procedure, patients were placed in a prone position for 3 hours. The primary outcome was restoration of corneal transparency, with a CEC density of more than 500 cells per square millimeter at the central cornea at 24 weeks after cell injection. Secondary outcomes were a corneal thickness of less than 630 μm and an improvement in best corrected visual acuity equivalent to two lines or more on a Landolt C eye chart at 24 weeks after cell injection.

RESULTS

At 24 weeks after cell injection, we recorded a CEC density of more than 500 cells per square millimeter (range, 947 to 2833) in 11 of the 11 treated eyes (100%; 95% confidence interval [CI], 72 to 100), of which 10 had a CEC density exceeding 1000 cells per square millimeter. A corneal thickness of less than 630 μm (range, 489 to 640) was attained in 10 of the 11 treated eyes (91%; 95% CI, 59 to 100), and an improvement in best corrected visual acuity of two lines or more was recorded in 9 of the 11 treated eyes (82%; 95% CI, 48 to 98).

CONCLUSIONS

Injection of human CECs supplemented with a ROCK inhibitor was followed by an increase in CEC density after 24 weeks in 11 persons with bullous keratopathy. (Funded by the Japan Agency for Medical Research and Development and others; UMIN number, UMIN000012534 .).

Production of Homogeneous Cultured Human Corneal Endothelial Cells Indispensable for Innovative Cell Therapy

Purpose

Cultured human corneal endothelial cells (cHCECs) are anticipated to become an alternative to donor corneas for the treatment of corneal endothelial dysfunction. The aim of this study was to establish proper culture protocols to successfully obtain a reproducibly homogeneous subpopulation (SP) with matured cHCEC functions and devoid of cell-state transition suitable for cell-injection therapy.

Methods

The presence of SPs in cHCECs was investigated in terms of surface cluster-of-differentiation (CD) marker expression level by flow cytometry, as combined analysis of CD markers can definitively specify the SP (effector cells) conceivably the most suitable for cell therapy among diverse SPs. The culture conditions were evaluated by flow cytometry in terms of the proportion (E-ratio) of effector cells designated by CD markers.

Results

Flow cytometry analysis identifying CD44-CD166+CD133-CD105-CD24-CD26- effector cells proved convenient and reliable for standardizing the culture procedures. To ascertain the reproducible production of cHCECs with E-ratios of more than 90% and with no karyotype abnormality, the preferred donor age was younger than 29 years. The continuous presence of Rho-associated protein kinase (ROCK)-inhibitor Y-27632 greatly increased the E-ratios, whereas the presence of transforming growth factor-beta/Smad-inhibitor SB431542 greatly reduced the number of recovered cHCECs. The seeding cell density during culture passages proved vital for maintaining a high E-ratio for extended passages. The continuous presence of ROCK-inhibitor Y-27632 throughout the cultures greatly improved the E-ratio.

Conclusions

Our findings elucidated the culture conditions needed to obtain reproducible cHCECs with high E-ratios, thus ensuring homogeneous cHCECs with matured functions for the treatment of corneal endothelial dysfunction.

The Different Binding Properties of Cultured Human Corneal Endothelial Cell Subpopulations to Descemet's Membrane Components

PURPOSE

To clarify the adherent properties of cultured human corneal endothelial cell (cHCEC) subpopulations (SPs).

METHODS

Each SP was prepared by controlling the culture conditions or by using magnetic cell separation, and then confirmed by staining with several cell-surface markers. Binding abilities of HCEC SPs were examined by adding the cells to culture plates immobilized with collagens, laminins, or proteoglycans, and then centrifuging the plates. Adhered cells were then evaluated by phase-contrast microscopy.

RESULTS

The cHCECs were bound to laminin-511, laminin-411, and Type-IV collagen in a concentration-dependent manner, yet weakly bound to Perlecan, Agrin, and TSP-1. Comparison of the influence of cell-suspension vehicles on cHCEC attachment showed that cells suspended in Opti-MEM-I or Opeguard-MA were bound to laminin, yet no binding was observed in cells suspended in BSS-Plus. Next, we compared the adherent properties of HCEC SPs. Both the fully differentiated, mature cHCEC SP and the epithelial-to-mesenchymal-transitioned (EMT)-phenotype SP were found to attach to laminin- or collagen-coated plates. Interestingly, the binding properties to laminins differed among those SPs. Although the level of cells adhered to the laminin-411-coated plate was the same among the cHCEC SPs, the fully differentiated, mature cHCEC SP was significantly more tightly bound to laminin-511 than was the EMT-phenotype SP.

CONCLUSIONS

The findings of this study suggest that the binding ability of cHCECs to major Descemet's membrane components is distinct among cHCEC SPs, and that Opti-MEM-I and Opeguard-MA are useful cell-suspension vehicles for cell-injection therapy.

Cell Homogeneity Indispensable for Regenerative Medicine by Cultured Human Corneal Endothelial Cells

PURPOSE

To identify the subpopulation (SP) among heterogeneous cultured human corneal endothelial cells (cHCECs) devoid of cell-state transition applicable for cell-based therapy.

METHODS

Subpopulation presence in cHCECs was confirmed via surface CD-marker expression level by flow cytometry. CD markers effective for distinguishing distinct SPs were selected by analyzing those on established cHCECs with a small cell area and high cell density. Contrasting features among three typical cHCEC SPs was confirmed by PCR array for extracellular matrix (ECM). Combined analysis of CD markers was performed to identify the SP (effector cells) applicable for therapy. ZO-1 and Na+/K+ ATPase, CD200, and HLA expression were compared among heterogeneous SPs.

RESULTS

Flow cytometry analysis identified the effector cell expressing CD166+CD105-CD44-∼+/-CD26-CD24-, but CD200-, and the presence of other SPs with CD166+ CD105-CD44+++ (CD26 and CD24, either + or -) was confirmed. PCR array revealed three distinct ECM expression profiles. Some SPs expressed ZO-1 and Na+/K+ ATPase at comparable levels with effector cells, while only one SP expressed CD200, but not on effector cells. Human leukocyte antigen expression was most reduced in the effector SP. The proportion of effector cells (E-ratio) inversely paralleled donor age and decreased during prolonged culture passages. The presence of Rho-associated protein kinase (ROCK) inhibitor increased the E-ratio in cHCECs. The average area of effector cells was approximately 200∼220 μm2, and the density of cHCECs exceeded 2500 cells/mm2.

CONCLUSIONS

A specified cultured effector cell population sharing the surface phenotypes with mature HCECs in corneal tissues may serve as an alternative to donor corneas for the treatment of corneal endothelial dysfunction.

Allogeneic Sensitization and Tolerance Induction After Corneal Endothelial Cell Transplantation in Mice

PURPOSE

We evaluated the allogeneic response after corneal endothelial cell transplantation in the anterior chamber (AC) in a new mouse model by examining the acquisition of a delayed-type hypersensitivity (DTH) response, induction of allogeneic AC-associated immune deviation (ACAID), and acquisition of delayed transplantation tolerance.

METHOD

The corneal eyecups from C57BL/6 mice were prepared. The epithelial layer was detached with EDTA solution and treated with trypsin to release mouse-derived primary corneal endothelial cells (mpCECs). The mpCECs (1 × 104 cells) were transplanted into the AC of the eye or subcutaneously (SC) into the neck of BALB/c mice. In the mouse model of endothelial cell transplantation, the endothelial cells in a 2-mm central area of the cornea were eliminated by cryoinjury. The mpCEC transplant model was evaluated by measuring allogeneic cell survival and corneal thickness. The allospecific DTH response and ACAID induction were evaluated 1 week after transplantation. The long-term transplantation tolerance was evaluated by observing a secondary penetrating keratoplasty (PKP) performed on the same donor C57BL/6 mice.

RESULTS

The SC injection of mpCECs induced a DTH response, whereas the AC injection induced ACAID. However, eyes inflamed by cryoinjury showed neither the DTH response nor ACAID following AC injection. The mpCECs survived for at least 1 week after injection. Penetrating keratoplasty allografts at 8 weeks after mpCEC transplantation survived indefinitely (100%).

CONCLUSIONS

The mpCECs display low allogenicity in the AC and are capable of inducing allogeneic tolerance. Corneal endothelial cell transplantation into the AC may represent a safe technique for allogeneic transplantation.

Concomitant Evaluation of a Panel of Exosome Proteins and MiRs for Qualification of Cultured Human Corneal Endothelial Cells

PURPOSE

We elucidate a method to use secreted miRNA profiles to qualify cultured human corneal endothelial cells (cHCECs) adaptable for cell-injection therapy.

METHODS

The variations of cHCECs in their composites of heterogeneous subpopulations (SPs) were verified in relation to their surface cluster-of-differentiation (CD) markers. Integrated analysis of micro RNA (miRNA) profiles in culture supernatants (CS) were investigated by 3D-Gene Human microRNA Chips. To validate 3D-Gene results, quantitative real-time PCR was done from numerous cultures with distinct morphology and SP composition. Exosomes and miRNAs in CS also were analyzed.

RESULTS

Secreted miRNA profiles among morphologically-diverse cHCEC SPs proved useful for individual distinction. Candidate miRNAs to discriminate CD44- SPs from those with CD44++ ∼ CD44+++ phenotypes were miRs 221-3p, 1246, 1915-3p, and 4732-5p. The levels of the latter-three miRs decreased dramatically in cHCEC CS without cell-state transition (CST) compared to those of control medium, whereas those from cHCECs with senescence-like CST showed an increase. MicroR184 decreased inversely in parallel with the upregulation of CD44 on cHCECs. CD9+ exosomes were more elevated in cHCEC CS with senescence-like CST than those without CST, indicating the possible import of these extracellular vesicles (EVs) into cHCECs without CST.

CONCLUSIONS

Cultured HCECs sharing a CD44- phenotype of matured HCECs may be discriminated by measuring the amount of miRNAs or exosome in CS. Thus, miRNA in CS may serve as a tool to qualify cHCECs. Future detailed analysis of cell-to-cell communication via these EVs might open novel pathways for a better understanding of CST in HCEC cultures.

Metabolic Plasticity in Cell State Homeostasis and Differentiation of Cultured Human Corneal Endothelial Cells

Purpose

To clarify whether cultured human corneal endothelial cells (cHCECs), heterogeneous in their differentiation state, exhibit distinctive energy metabolism with the aim to develop a reliable method to sort cHCECs applicable for regenerative medicine.

Methods

The presence of cHCEC subpopulations (SPs) was verified via surface cluster-of-differentiation (CD) marker expression. Cultured HCEC metabolic extracts or corresponding culture supernatants with distinctive cellular phenotypes in regard to energy-metabolism-related functional markers c-Myc and CD44 were prepared and analyzed via capillary electrophoresis-tandem mass spectrometry. The metabolic requirements of heterogeneous SPs of cHCECs were also investigated.

Results

After successfully discriminating SPs, as verified via surface CD markers in terms of their secretory metabolites, we found that the CD44+++ SP with cell-state transition (CST) exhibited disposition for anaerobic glycolysis, whereas the CD44-SP without CST was disposed to mitochondria-dependent oxidative phosphorylation (OXPHOS). These results raised the possibility of establishing effective culture conditions to selectively expand mature cHCECs with a hexagonal cobblestone shape and inclination for mitochondria-dependent OXPHOS.

Conclusions

The findings of this study open a pathway for monitoring the disposition of cHCECs via their energy metabolism, thus leading to safe and stable regenerative medicine by use of metabolically defined cHCECs in cell-suspension form.

Gene Signature-Based Development of ELISA Assays for Reproducible Qualification of Cultured Human Corneal Endothelial Cells

PURPOSE

To develop a method to qualify the function of cultured human corneal endothelial cells (cHCECs) applicable for clinical settings.

METHODS

The diversified gene and microRNA (miRNA) signatures in HCECs from a variety of tissue donors were confirmed by three-dimensional (3D) gene human miRNA profiling. These were compared with those of more than 20 cHCECs distinct in their cell morphology or culture lots. Candidate genes were selected after quantitative (q)RT-PCR validation, and gene products were assayed by ELISA. After three additional screening steps, final candidate cytokines for qualification were selected.

RESULTS

Gene and miRNA signatures among distinct cHCEC lots were greatly diversified compared with those among fresh tissues from different age donors. By comparing more than 20 lots of cultures, 32 candidate genes were assigned to be seemingly linked to distinct cHCEC morphologic features. The validation of candidate genes by qRT-PCR revealed the genes, either upregulated or downregulated, corresponding to morphologic variances in cHCECs (e.g., epithelial-mesenchymal transition or cell senescence). Further adding the ELISA results by Bio-Plex Human Cytokine 27-Plex Panel, 11 candidate cytokines suitable to qualify cHCEC function were selected. In consideration of the presence of these cytokines in the anterior chamber, IL-8, tissue inhibitors of metalloproteinases 1 (TIMP-1), monocyte chemotactic protein-1 (MCP-1), and platelet-derived growth factor-BB (PDGF-BB) were ultimately selected and applied in practice for the qualification of cHCECs actually used in our clinical cell-injection studies.

CONCLUSIONS

The specified cytokines properly discriminating the functional features of cHCECs indicates a correlation between profiling signatures and cell morphology.

Improvement of luminescence properties of rubidium vanadate, RbVO3, phosphors by erbium doping in the crystal lattice

The thermal quenching effect of RbVO₃ phosphor was effectively improved by Er³⁺ doping into the lattice, as a result, the emission intensity of the phosphor was successfully enhanced.

Protein S is protective in pulmonary fibrosis

Essentials Epithelial cell apoptosis is critical in the pathogenesis of idiopathic pulmonary fibrosis. Protein S, a circulating anticoagulant, inhibited apoptosis of lung epithelial cells. Overexpression of protein S in lung cells reduced bleomycin-induced pulmonary fibrosis. Intranasal therapy with exogenous protein S ameliorated bleomycin-induced pulmonary fibrosis.

SUMMARY

Background Pulmonary fibrosis is the terminal stage of interstitial lung diseases, some of them being incurable and of unknown etiology. Apoptosis plays a critical role in lung fibrogenesis. Protein S is a plasma anticoagulant with potent antiapoptotic activity. The role of protein S in pulmonary fibrosis is unknown. Objectives To evaluate the clinical relevance of protein S and its protective role in pulmonary fibrosis. Methods and Results The circulating level of protein S was measured in patients with pulmonary fibrosis and controls by the use of enzyme immunoassays. Pulmonary fibrosis was induced with bleomycin in transgenic mice overexpressing human protein S and wild-type mice, and exogenous protein S or vehicle was administered to wild-type mice; fibrosis was then compared in both models. Patients with pulmonary fibrosis had reduced circulating levels of protein S as compared with controls. Inflammatory changes, the levels of profibrotic cytokines, fibrosis score, hydroxyproline content in the lungs and oxygen desaturation were significantly reduced in protein S-transgenic mice as compared with wild-type mice. Wild-type mice treated with exogenous protein S showed significant decreases in the levels of inflammatory and profibrotic markers and fibrosis in the lungs as compared with untreated control mice. After bleomycin infusion, mice overexpressing human protein S showed significantly low caspase-3 activity, enhanced expression of antiapoptotic molecules and enhanced Akt and Axl kinase phosphorylation as compared with wild-type counterparts. Protein S also inhibited apoptosis of alveolar epithelial cells in vitro. Conclusions These observations suggest clinical relevance and a protective role of protein S in pulmonary fibrosis.

Correlation between Serum IgE and Salivary Cortisol Levels in Subjects with Type I Allergic Disorders

This study compares the relationship between serum IgE and salivary Cortisol levels in 42 normal and in 18 type I allergic subjects. Levels of serum total IgE and salivary Cortisol were determined with the UniCAP system and ELISA respectively. In the type I allergic subjects, there was a significant correlation between serum IgE and salivary Cortisol levels ( p < 0.01). In the normal subjects, on the other hand, no correlation was found. These findings suggest that there may be an association between stress and allergic disorders.

Epicutaneous immunotherapy with a hypoallergenic Bet v 1 suppresses allergic asthma in a murine model

BACKGROUND

Due to reduced allergic potency, hypoallergenic variants have been suggested as safer and potentially more efficacious alternative to the corresponding wild-type allergens in allergen-specific immunotherapy. Here, we aimed at investigating the efficacy of recombinant Bet v 1B2, a hypoallergenic folding variant of Bet v 1, in epicutaneous immunotherapy to suppress asthmatic features using a murine model of birch pollen allergy.

METHODS AND RESULTS

Before, or after sensitization with rBet v 1 plus ALUMW and intranasal challenges with birch pollen extract, BALB/c mice received epicutaneous immunization (EPI) with rBet v 1, or rBet v 1B2 on their depilated back. Prophylactic EPI with rBet v 1B2, but not with rBet v 1, suppressed serum levels of Bet v 1-specific IgE antibodies and reduced the number of eosinophils and the concentrations of Th2 cytokines in bronchoalveolar lavage. In an established allergic condition, serum levels of Bet v 1-specific IgE antibodies were similar between PBS-treated control mice and EPI-treated mice. However, therapeutic EPI with rBet v 1B2, but not with rBet v 1, significantly suppressed the development of airway inflammation and lung function impairment.

CONCLUSION

This study is the first to show the effect of therapeutic EPI with a recombinant form of a hypoallergenic folding variant on the suppression of asthmatic features. Our results suggest that rBet v 1B2 along with its reduced IgE-binding capacity could be a preferred therapeutic allergen than wild-type rBet v 1 in epicutaneous immunotherapy of birch pollen-induced allergic asthma, in particular due to a lower risk of allergic side effect.

Protein S exacerbates alcoholic hepatitis by stimulating liver natural killer T cells

BACKGROUND

Alcohol consumption is a major cause of liver injury but the mechanisms are not completely understood. Protein S (PS) is an anticoagulant glycoprotein with multiple functions. The role of PS in liver injury is unknown.

OBJECTIVES

This study investigated the role of PS in acute alcoholic hepatitis.

METHODS

A mouse overexpressing human PS (hPS-TG) was generated in which acute hepatitis was induced by intraperitoneal injection of ethanol.

RESULTS

The levels of serum liver enzymes and liver tissue inflammatory cytokines and the degree of hepatic steatosis were significantly increased in hPS-TG mice treated with ethanol compared with ethanol-treated wild type (WT) mice. Cell expansion, activation and inhibition of apoptosis were significantly augmented in natural killer T (NKT) cells from hPS-TG mice compared with WT mice. Liver mononuclear cells from hPS-TG mice express higher levels of inflammatory cytokines than those from WT mice after stimulation with a specific stimulant of NKT cells in vitro. In a co-culture system of hepatocytes and NKT cells, the effects of PS on ethanol-mediated cell injury were suppressed by a CD1d neutralizing antibody. Alcoholic liver injury was significantly improved in mice pre-treated with PS siRNA and anti-protein S antibody compared with control mice. Patients with alcoholic hepatitis showed significantly increased plasma PS levels and enhanced liver expression of PS and CD1d compared with controls.

CONCLUSIONS

The results of this study suggest that PS exacerbates acute alcoholic hepatitis by inhibiting apoptosis of activated NKT cells.

MUC1 protein induces urokinase-type plasminogen activator (uPA) by forming a complex with NF-κB p65 transcription factor and binding to the uPA promoter, leading to enhanced invasiveness of cancer cells

Mucin 1 (MUC1) is overexpressed in various human malignant tumors and its expression is correlated with a poor prognosis. MUC1 engages in signal transduction by interacting with receptors for growth and differentiation factors, which contributes to the growth and survival of cancer cells. However, the mechanism by which MUC1 promotes cancer cell invasion remains unclear. Microarray analysis revealed that expression of urokinase-type plasminogen activator (uPA) was elevated in MUC1-overexpressing cells. Furthermore, up- and down-modulation of MUC1 expression was clearly correlated with the change of uPA expression. An immunochemical study showed that the distribution of uPA coincided with that of MUC1 in various human cancer tissues. The MUC1 C-terminal domain (MUC1-CD) was associated with nuclear factor-κB (NF-κB) p65 in MUC1-expressing cells. Chromatin immunoprecipitation (ChIP) assays demonstrated that MUC1-CD existed with NF-κB p65 on the uPA promoter. Luciferase assays indicated that the uPA transcriptional activity was correlated with the level of MUC1 expression and that this MUC1-enhancing effect on the uPA transcription was abolished by introduction of mutations into the NF-κB binding sites on the uPA promoter. These results indicate that formation of the MUC1-CD and NF-κB p65 complex enhanced nuclear translocation of NF-κB p65 and subsequent occupancy of NF-κB binding region on the uPA promoter, leading to elevated transcription of uPA. We also demonstrated that uPA induced by MUC1 enhanced the matrix metalloproteinase (MMP)-2 and -9 activities, and consequently promoted cancer cell invasion. Thus, a MUC1 co-operating NF-κB signaling pathway plays a critical role in cancer cell invasion in MUC1-expressing cells.

Negative regulation of Toll-like receptor-4 signaling through the binding of glycosylphosphatidylinositol-anchored glycoprotein, CD14, with the sialic acid-binding lectin, CD33

When monocyte-derived immature dendritic cells (imDCs) were stimulated with LPS in the presence of anti-CD33/Siglec-3 mAb, the production of IL-12 and phosphorylation of NF-κB decreased significantly. The cell surface proteins of imDCs were chemically cross-linked, and CD33-linked proteins were analyzed by SDS-PAGE and immunoblotting. It was CD14 that was found to be cross-linked with CD33. A proximity ligation assay also indicated that CD33 was colocalized with CD14 on the cell surface of imDCs. Sialic acid-dependent binding of CD33 to CD14 was confirmed by a plate assay using recombinant CD33 and CD14. Three types of cells (HEK293T cells expressing the LPS receptor complex (Toll-like receptor (TLR) cells), and the LPS receptor complex plus either wild-type CD33 (TLR/CD33WT cells) or mutated CD33 without sialic acid-binding activity (TLR/CD33RA cells)) were prepared, and then the binding and uptake of LPS were investigated. Although the level of LPS bound on the cell surface was similar among these cells, the uptake of LPS was reduced in TLR/CD33WT cells. A higher level of CD14-bound LPS and a lower level of TLR4-bound LPS were detected in TLR/CD33WT cells compared with the other two cell types, probably due to reduced presentation of LPS from CD14 to TLR4. Phosphorylation of NF-κB after stimulation with LPS was also compared. Wild-type CD33 but not mutated CD33 significantly reduced the phosphorylation of NF-κB. These results suggest that CD14 is an endogenous ligand for CD33 and that ligation of CD33 with CD14 modulates with the presentation of LPS from CD14 to TLR4, leading to down-regulation of TLR4-mediated signaling.

Epicutaneous immune modulation with Bet v 1 plus R848 suppresses allergic asthma in a murine model

BACKGROUND

Combining allergen(s) with an adjuvant is a strategy to improve the efficacy and safety of allergen-specific immunotherapy. Here, we aimed at investigating the adjuvant effects of polyadenylic-polyuridylic acid (poly(A:U)), a TLR3 agonist, and R848 (resiquimod), a TLR7 agonist, in epicutaneous immunotherapy with Bet v 1, the major birch pollen allergen, to intervene in birch pollen allergy.

METHODS AND RESULTS

BALB/c mice received epicutaneous immunization (EPI) with recombinant Bet v 1 (rBet v 1) alone, or plus poly(A:U), or R848 on their depilated back using patches. Among the groups, EPI with rBet v 1 and R848 induced detectable levels of IFN-γ-producing CD4(+) T cells in lymph nodes and Bet v 1-specific IgG2a antibodies in the sera of mice. Before or after EPI, mice were sensitized with rBet v 1 plus aluminium hydroxide adjuvant and intranasally challenged with birch pollen extract. Prophylactic EPI with rBet v 1 plus R848 inhibited the production of biologically active Bet v 1-specific IgE antibodies in sensitization. Prophylactic and therapeutic EPI with rBet v 1 plus R848 suppressed lung inflammation upon challenges. Remarkably, only rBet v 1 plus R848 reduced the development of enhanced pause (PenH), a substituted parameter for airway hyper-reactivity, in challenged mice. In contrast to R848, poly(A:U) did not present adjuvant effect on the suppression of asthmatic features.

CONCLUSION

Epicutaneous immunization with rBet v 1 plus R848 induced predominant Bet v 1-specific Th1 responses and efficiently suppressed asthmatic features elicited by birch pollen. R848 could be a promising adjuvant in epicutaneous immunotherapy for birch pollen-induced allergic asthma.