Relation Between Corneal Dendritic Cell Density and Tear Film Stability in Patients with Epidemic Keratoconjunctivitis Associated Dry Eye.

PURPOSE: To clarify the ocular surface features of patients with recent history of epidemic keratoconjunctivitis (EKC) and the relation between corneal dendritic cells (DCs) and ocular discomfort. METHODS: Normal controls (NC) and dry eye (DE) patients without EKC were recruited. Patients with recent EKC history (onset >4 weeks, but <20 weeks) were recruited as EKC + DE group (with dry eye) or EKC-DE group (without dry eye). Ocular surface disease index (OSDI) questionnaire, tear film parameters including lipid layer thickness, first tear break-up time (fBUT), average tear break-up time (aBUT), tear meniscus height and Schirmer I test, meibomian gland parameters, and in vivo corneal confocal microscopy were evaluated. RESULTS: 50 subjects in the NC group, 83 patients in the DE group, 76 patients in the EKC + DE group, and 38 patients in the EKC-DE group were included. Compared with the NC, DE, and EKC-DE groups, the EKC + DE group represented higher OSDI, lid margin, and meibum score (p < 0.05). In the EKC + DE group, the tear volume (10.5 ± 3.7 mm) was significantly higher than in the DE group (8.1 ± 2.8 mm, p < 0.001). The DC density in the EKC + DE group (29.98 ± 15.38 cells/image) was significantly higher than in NC, DE, and EKC-DE groups (4.68 ± 4.05 cells/image) (p < 0.001). The DC density was positively correlated with OSDI, lid margin, and meibum score (all p < 0.01) while inversely correlated with fBUT, aBUT (all p < 0.001) in the EKC + DE group. CONCLUSIONS: Corneal DC density significantly correlates to ocular discomfort and tear film instability in patients with recent EKC history who suffer from DE without aqueous tear deficiency.

Downregulation of p38 MAPK Signaling Pathway Ameliorates Tissue-Engineered Corneal Epithelium.

Tissue-engineered corneal epithelium transplantation is effective treatment for severe limbal stem cell deficiency (LSCD), while epithelial terminal differentiation, tans-differentiation, and insufficient stem cell during construction affect the quality of tissue-engineered corneal epithelium. In this study, we applied SB203580 in the culture medium to downregulate the p38 mitogen-activated protein kinase (MAPK) signaling pathway during construction of tissue-engineered corneal epithelium. With application of SB203580, tissue-engineered corneal epithelium showed enhanced strength and condensed structure. The expression of progenitor cell markers ATP-binding cassette sub-family G member 2, tumor protein p63, keratin 14, and Wnt family member 7A was increased, differentiation markers keratin 12, paired box 6, keratin 10, and keratin 13 and trans-differentiation markers actin alpha 2, smooth muscle and snail family transcriptional repressor 1 was decreased, while cell junction markers claudin 1 and cadherin 1 was increased in the tissue-engineered corneal epithelium. The Wnt/catenin beta 1 signaling pathway was upregulated in the epithelium after p38 MAPK inhibition. Transplantation of tissue-engineered corneal epithelium treated with SB203580 to rabbit LSCD model showed faster wound healing and improved epithelial quality. We conclude that downregulation of p38 MAPK signaling pathway helps maintain the stemness and prevent terminal differentiation and abnormal differentiation of corneal epithelial cells during epithelium construction process, and thus can improve the quality of tissue-engineered corneal epithelium. Impact statement Downregulation of p38 MAPK signaling pathway helps maintain the self-renewal of limbal stem cells and prevents terminal differentiation and abnormal differentiation of corneal epithelial cells. Small molecules modulating p38 MAPK signaling pathway ameliorate tissue-engineered corneal epithelium.

Ovalbumin-Induced Allergic Inflammation Diminishes Cross-Linked Collagen Structures in an Experimental Rabbit Model of Corneal Cross-Linking.

Background: Allergic conjunctivitis (AC) is one of the reported potential risk factors of progression in keratoconus patients after corneal cross-linking surgery; however, the causal relationship is still inconclusive. Recent studies have indicated that various inflammatory cytokines play a vital role in the development of primary keratoconus. It is still unclear whether these inflammatory mediators also trigger CXL failures. This study aimed to investigate the impact of AC on the rabbit corneas after trans-epithelial corneal cross-linking (TCXL). Methods: A total of six rabbits were kept untreated as the normal control (NC) group. A total of 18 rabbits were treated by TCXL and divided into three groups (six in each group), namely, no treatment (TCXL group); induction of AC (TCXL + AC group); and induction of AC plus topical prednisolone acetate (TCXL + AC + PA group), according to additional treatment. AC was induced by topical application of ovalbumin after intraperitoneal pre-sensitization with ovalbumin. Rabbits were evaluated by slit lamp, in vivo laser scanning confocal microscopy, anterior segment optical coherence tomography, and measurement of corneal biomechanics. The cornea specimens were collected for the transmission electron microscope, the collagenase I digestion test, and PCR assay for TNF-α, IL-6, IL-1ß, matrix metalloproteinase 9 (MMP-9), lysyl oxidase (LOX), and tissue inhibitor of metalloproteinases 1 (TIMP-1) on the day (D) 28. Results: On D28, the TNF-α, IL-6, IL-1ß, MMP-9, and LOX levels were significantly increased while the TIMP-1 was decreased in the TCXL + AC group when compared with the TCXL and TCXL + AC + PA groups. In vivo confocal microscopy revealed that at a depth of 150-210 µm, a trabecular patterned hyperdense structure surrounded by elongated needle-like processes could be observed in the TCXL and TCXL + AC + PA groups, but hardly seen in the TCXL + AC group. The demarcation lines were indistinct and blurred in the TCXL + AC group. An electron microscope demonstrated less interlacing fibril lamellae and higher interfibrillar spacing in the TCXL + AC group. The stability of corneal biomechanics and resistance to collagenase were decreased in the TCXL + AC group. Conclusion: The corneal microstructures induced by TCXL and biomechanical stability were diminished in rabbits with AC but could be maintained by topical anti-inflammatory treatment. Our results supported the causal relationship between altered cytokine profiles and corneal microstructure after primary corneal cross-linking.

Cytokine Changes in the Aqueous Humor in Rubella-Related Fuchs Heterochromic Iridocyclitis.

This retrospective study is aimed at determining the correlation between cytokine levels and virus status in the aqueous humor of 38 patients with Fuchs heterochromic iridocyclitis (FHI) with/without a viral presence between May 2017 and January 2020. The levels of cytokines were analyzed in the groups with and without virus-related FHI. Among the patients, 50% had rubella virus, 5.26% had cytomegalovirus, and 2.63% had herpes simplex virus infections. The expression of interleukin-6 (IL-6) and IL-8 was significantly higher, and that of basic fibroblast growth factor (bFGF) was significantly lower in the virus-positive group than in the virus-negative group (P = 0.015, P = 0.001, and P = 0.001, respectively). Although there was no significant difference in the mean expression of vascular cell adhesion protein 1 (VCAM-1), IL-10, and vascular endothelial growth factor (VEGF), that of VCAM-1 and IL-10 was higher (M = 1338 and M = 1390, respectively; M = 6.225 and 10.600, respectively) and that of VEGF was lower (M = 134.5 and M = 38.70, respectively) in the virus-positive group than in the virus-negative group. Similar findings were observed for the expressions of IL-6, IL-8, and bFGF in the rubella-positive and rubella-negative groups. Viral presence was highly related to FHI, especially that of the rubella virus. High levels of inflammatory cytokines and low levels of neovascularization-related factors are involved in rubella-related FHI. These study findings could be helpful in the diagnosis and treatment of FHI.

Ubiquitin-conjugating enzyme E2T regulates cell proliferation and migration in cholangiocarcinoma.

Ubiquitin-conjugating enzyme E2T (UBE2T) is overexpressed in several human cancer cells, but a role in cholangiocarcinoma (CAA) progression has not been investigated. We analyzed the expression of UBE2T in CAA tissues. Then, we generated UBE2T deregulation models in which it was overexpressed or silenced, and examined the effects on CAA malignant progression by flow cytometry, western blot, MTT assay, wound healing assay and transwell assay. We report the involvement of UBE2T in CAA malignant progression. UBE2T was found to be highly expressed in human CAA cells both in vitro and in vivo. Overexpression of UBE2T significantly enhanced epithelial-to-mesenchymal transition, proliferation, migration and invasion of CAA cells in vitro, while silencing UBE2T had opposing effects. Furthermore, UBE2T appears to exert its effects via the mammalian target of rapamycin (mTOR) pathway as the cellular effects caused by UBE2T overexpression are inhibited by the mTOR inhibitor rapamycin. Our findings suggest that UBE2T may have potential as a new therapeutic target for the prevention or treatment of CAA.

Inhibitory effects of genistein on metastasis of human hepatocellular carcinoma.

AIM: To investigate the inhibitory effects of genistein on metastasis of MHCC97-H hepatocellular carcinoma cells and to explore the underlying mechanism. METHODS: MHCC97-H hepatocellular carcinoma cells were exposed to genistein. A cell attachment assay was carried out in a microculture well pre-coated with fibronectin. The invasive activity of tumor cells was assayed in a transwell cell culture chamber, and cell cycle and apoptosis were evaluated by a functional assay. In addition, the expression and phosphorylation of FAK were detected by Western blotting. In situ xenograft transplantation of hepatocellular carcinoma was performed in 12 nude mice and lung metastasis of hepatocellular carcinoma was observed. RESULTS: Genistein significantly inhibited the growth of MHCC97-H cells in vitro. Adhesion and invasiveness of MHCC97-H cells were inhibited in a concentration-dependent fashion, and the inhibitory effect of genistein was more potent in the 10 microg/mL and 20 microg/mL genistein-treated groups. Genistein caused G(0)/G(1) cell cycle arrest, an S phase decrease, and increased apoptosis. The expression and phosphorylation of FAK in MHCC-97H cells were significantly decreased. In situ xenograft transplantation of hepatocellular carcinoma was also significantly suppressed by genistein. The number of pulmonary micrometastatic foci in the genistein group was significantly lower compared with the control group (12.3 +/- 1.8 vs 16.6 +/- 2.6, P < 0.05). CONCLUSION: Genistein appears to be a promising agent in the inhibition of metastasis of hepatocellular carcinoma.