Epithelial Dendritic Cells Research Articles

Dendritic Cell Density and Morphology Can Be Used to Differentiate Vernal Keratoconjunctivitis from Allergic Conjunctivitis.

The aim of the study was to compare the distribution of corneal and conjunctival epithelial dendritic cells (DCs) in vernal keratoconjunctivitis (VKC), allergic conjunctivitis (AC), and non-allergic controls to examine if the allergy type causes differences in immune cell activation. The prospective study included 60 participants: 20 with VKC, 20 with AC, and 20 non-allergic controls. In vivo confocal microscopy was performed on the right eye. The locations scanned included the corneal centre, inferior whorl, corneal periphery, corneal limbus, and bulbar conjunctiva. The DCs were counted manually, and their morphology was assessed for the largest cell body size, the presence of dendrites, and the presence of long and thick dendrites. The DC density was higher in VKC and AC compared to non-allergic group at all locations (p ≤ 0.01) except at the inferior whorl. The DC density in VKC participants was significantly higher than in AC at the limbus (p < 0.001) but not at other locations. Both the AC and the VKC group had larger DC bodies at the corneal periphery and limbus compared to the non-allergic group (p ≤ 0.03). The study found a higher proportion of participants with DCs exhibiting long dendrites at both the corneal periphery in AC (p = 0.01) and at the corneal centre, periphery, and limbus in VKC, compared to the non-allergic group (p ≤ 0.001). In conclusion, a higher DC density at the limbus may be a marker of more severe VKC. DCs with larger cell bodies and a greater proportion of participants with DCs displaying long dendrites can be potential markers to differentiate allergy from non-allergy, and more severe forms of allergy from milder forms.

Increased dendritic cell density and altered morphology in allergic conjunctivitis

BackgroundCorneal and conjunctival epithelial dendritic cells (DC) have an established role in vernal keratoconjunctivitis, however, their role in more prevalent forms of allergic eye disease remains unclear. This study evaluated corneal and conjunctival epithelial DC density, morphology, and distribution observed using in vivo confocal microscopy (IVCM) in allergic conjunctivitis.MethodsIn this prospective, observational study, 66 participants (mean age 36.6 ± 12.0 years, 56% female): 33 with allergic conjunctivitis and 33 controls were recruited. IVCM was performed at the corneal centre, inferior whorl, corneal periphery, corneal limbus, and temporal bulbar conjunctiva. DC were counted and their morphology was assessed as follows: largest cell body size, presence of dendrites, and presence of long and thick dendrites. Mixed model analysis (DC density) and non-parametric tests (DC morphology) were used.ResultsDC density was higher in allergic participants at all locations (p ≤ 0.01), (corneal centre median (IQR) 21.9 (8.7–50.9) cells/mm2 vs 13.1 (2.8–22.8) cells/mm2; periphery 37.5 (15.6-67.2) cells/mm2 vs 20 (9.4–32.5) cells/mm2; limbus 75 (60-120) cells/mm2 vs 58.1 (44.4–66.2) cells/mm2; conjunctiva 10 (0–54.4) cells/mm2 vs 0.6 (0–5.6) cells/mm2, but not at the inferior whorl 21.9 (6.2–34.4) cells/mm2 vs 12.5 (1.9–37.5) cells/mm2, p = 0.20. At the corneal centre, allergic participants had larger DC bodies (p = 0.02), a higher proportion of DC with dendrites (p = 0.02) and long dendrites (p = 0.003) compared to controls.ConclusionsCorneal and conjunctival DC density was increased, and morphology altered in allergic conjunctivitis. These findings imply that the ocular surface immune response was upregulated and support an increased antigen-capture capacity of DC in allergic conjunctivitis.

Corneal Epithelial Dendritic Cells: An Objective Indicator for Ocular Surface Inflammation in Patients with Obstructive Meibomian Gland Dysfunction?

ABSTRACT Purpose To examine whether corneal epithelial dendritic cells (CEDC) could serve as an indicator to distinguish obstructive meibomian gland dysfunction (MGD) with or without ocular surface inflammation (OSI). Methods We performed a case-control study on patients with diagnosed obstructive MGD between August 2017 and November 2019. Results 30 MGD cases and 25 healthy controls were recruited. The classification of MGD patients with and without OSI was based on the tear pro-inflammatory cytokine levels. Compared with the MGD without OSI and the control group, a higher CEDC density was detected in the MGD with OSI subgroup. The presence of >15.6 cells/mm2 CEDC had a sensitivity of 73% and specificity of 75% for the diagnosis of MGD with OSI. Conclusions OSI is not present in all patients with obstructive MGD. Evaluation of CEDC density in the central cornea may help identify whether MGD is concomitant with OSI.

Diurnal changes and topographical distribution of ocular surface epithelial dendritic cells in humans, and repeatability of density and morphology assessment.

Dendritic cells (DC) play a crucial role in ocular surface defence. DC can be visualised in vivo by confocal microscopy but have not yet been fully characterised in humans. This study investigated the diurnal variation, topographical distribution and repeatability of DC density and morphology measurements. In vivo confocal microscopy (IVCM) was conducted on 20 healthy participants (mean age 32.7± 6.4 years, 50% female) at baseline and repeated after 30 minutes, 2, 6 and 24 h. Images were captured at the corneal centre, inferior whorl, corneal periphery, limbus and bulbar conjunctiva. DC were counted manually, and their morphology was assessed for cell body size, presence of dendrites, and presence of long and thick dendrites. Mixed-model analysis, non-parametric analyses, Bland and Altman plots, coefficient of repeatability (CoR) and kappa were used. There were no significant changes in DC density (p≥ 0.74) or morphology (p> 0.07) at any location over the 24-h period. The highest DC density was observed at the corneal limbus followed by the peripheral cornea (p< 0.001), with the lowest density at the corneal centre, inferior whorl and bulbar conjunctiva. Most DC at the corneal periphery, limbus and bulbar conjunctiva had larger cell bodies compared with the corneal centre (p≤ 0.01), and the presence of long dendrites was observed mostly at non-central locations. Day-to-day CoR for DC density ranged from ±28.1 cells/mm2 at the corneal centre to ±56.4 cells/mm2 at the limbus. Day-to-day agreement of DC morphology determined by kappa ranged from 0.5 to 0.95 for cell body size, 0.60 to 0.95 for presence of dendrites, and 0.55 to 0.80 for the presence of long dendrites at various locations. No diurnal changes are apparent in corneal or conjunctival DC. Substantial topographical differences exist in DC density and morphology. IVCM provides good repeatability of DC density and acceptable agreement of DC morphology.

Corneal epithelial dendritic cells, tear neuropeptides and corneal nerves continue to be affected more than 12 months after LASIK.

LASIK causes corneal nerve damage and may affect the neuro-immune crosstalk. This study examined the effects of LASIK on corneal epithelial dendritic cells (CEDC) density and morphology and explored their relationships with corneal nerves and tear neuropeptides. A grading system was developed to assess CEDC morphology. Intra- and inter-observer repeatability of the CEDC morphology grading system was established using kappa (κ). In vivo confocal microscope images of the central cornea were captured from 20 participants who had undergone LASIK 12-16 months earlier and 20 controls (age 18-32 years, 55%F). CEDC density was counted manually, and CEDC morphology was assessed using a new grading system. CEDC sub-types (contacting nerves [CEDCc] and not contacting nerves [CEDCnc]) were also assessed. Differences in CEDC density and morphology were examined using mixed models and chi-squared test. Relationships between CEDC and corneal nerve parameters and tear substance P were explored using Spearman's correlation. Excellent intra- and inter-observer repeatability was demonstrated for the grading system (κ=0.82-0.97). In post-LASIK participants, CEDC density was lower compared with controls (5 [0-34] vs. 21 [7-77] cells/mm2 ; p= 0.01), and the proportion of CEDC with thick dendrites was higher (55%-73% vs. 11%-21%, p< 0.003). Higher tear substance P levels were associated with higher CEDC density (rho=0.48, p= 0.003). Fewer nerve interconnections were observed in participants in whom CEDC had dendrites (p= 0.03). CEDC sub-types followed a similar pattern to CEDC. The findings suggest that CEDC may remain altered more than 12 months post-LASIK. The association with substance P suggests a role for CEDC in corneal neurogenic inflammation.

Immunohistochemical association with histological features of Hassall’s corpuscles in human fetal thymus

Background - Hassall’s corpuscles (HC) are balls of flattened medullary epithelial cells which are characteristic features of the thymus. Thymus is truly an ‘organ of mystery’ which has kept scholars in dark still continues to elucidate researchers till date. Aim- To study themicroscopic features of human fetal thymus along withthe differentiation and maturation process of the Hassall’s Corpuscles (HC) in human fetal thymus by using the immunohistochemical markers. Materials &amp; Methods- Total 20 aborted and still born fetuses ranging from 17-39 weeks of gestation were used for the study. After embalming, meticulous dissection, thymusgland was weighed and fixed with formalin. The various histological and histometric parameters were observed. Another set of microscopic slides were subjected to immunohistochemical studies by staining with primary antibodies (Cytokeratin, S100 and Vimentin) to study the presence of epithelial, histiocytic and mesenchymal components in fetal thymus and to know the nature of differentiation of the Hassall’s corpuscles, epithelial reticular cells and dendritic cells in the fetal thymus. Observations &amp; Results: Microscopic examination of serial section of thymus revealed few patterns of shapes of HC’s. Based on the morphological features, the corpuscles were classified as Solid Hassal Corpuscles (SHC), Cystic I (CHCI) and Cystic II(CHC II) and Degenerating(DHC). Epithelial cells of the HC were positive for cytokeratin which was less intensely positive in Solid Hassall Corpuscles (SHC) and intensely positive in primary and secondary cystic Hassall Corpuscles (CHC I and CHC II). The solid corpuscles (SHC) with homogenous mass were seen to be intensely positive whereas the central core in cystic varieties (CHC 1 &amp; CHC II) seems to be less positive with S 100 (marker for dendritic cells, histocytes and keratinocytes). Vimentin is intermediate cytoplasmic proteins expressed in the cells of mesenchymal differentiation found negative in the complete sections studied. Conclusion:The various types of HC encountered with different structural morphology could represent a stage of maturation in the developmental process. Hence HCs’ were arranged in a sequential order of development stages within the age group of the present study. The presence of Solid Hassall’s Corpuscle at the periphery of the medulla and Degenerating Hassall’s Corpuscle(DHC) at the central core of the medulla confirms the direction of maturation is from the periphery to the center of the medulla. Hence there is gradual increase in the expression of cytokeratin from solid to cystic Hassall’s corpuscles. Bangladesh Journal of Medical Science Vol. 21 No. 03 July’22 Page: 529-539

HSV-1 Infection of Epithelial Dendritic Cells Is a Critical Strategy for Interfering with Antiviral Immunity.

Herpes simplex virus type 1 (HSV-1), an α subgroup member of the human herpesvirus family, infects cells via the binding of its various envelope glycoproteins to cellular membrane receptors, one of which is herpes virus entry mediator (HVEM), expressed on dendritic cells. Here, HVEM gene-deficient mice were used to investigate the immunologic effect elicited by the HSV-1 infection of dendritic cells. Dendritic cells expressing the surface marker CD11c showed an abnormal biological phenotype, including the altered transcription of various immune signaling molecules and inflammatory factors associated with innate immunity after viral replication. Furthermore, the viral infection of dendritic cells interfered with dendritic cell function in the lymph nodes, where these cells normally play roles in activating the T-cell response. Additionally, the mild clinicopathological manifestations observed during the acute phase of HSV-1 infection were associated with viral replication in dendritic cells.

Altered Corneal Epithelial Dendritic Cell Morphology and Phenotype Following Acute Exposure to Hyperosmolar Saline.

PurposeThe purpose of this study was to assess the morphological and phenotypic responses of corneal epithelial dendritic cells (DCs) to acute topical hyperosmolar stress, given a pathogenic role for tear hyperosmolarity in dry eye disease (DED).MethodsC57BL/6J mice were anesthetized and received 350 mOsm/L (physiological; n = 5 mice), 450 mOsm/L (n = 6), or 600 mOsm/L (n = 6) saline on a randomly assigned eye. Corneas were harvested 2 hours later. Immunofluorescent staining was performed using CD45, CD86, and CD68 antibodies to investigate DC morphology (density, viability, field area, circularity, and dendritic complexity) and immunological phenotype. Flow cytometry was used to confirm CD86 and CD68 expression in CD11c+ DCs, using C57BL/6J mice that received topical applications of 350 mOsm/L, 450 mOsm/L, or 600 mOsm/L (n = 5 per group) bilaterally for 2 hours.ResultsFollowing exposure to 450 mOsm/L topical saline for 2 hours, DCs in the central and peripheral cornea were larger (field area: Pcentral = 0.005, Pperipheral = 0.037; circularity: Pcentral = 0.026, and Pperipheral = 0.013) and had higher expression of CD86 compared with 350 mOsm/L controls (immunofluorescence: P < 0.0001; flow cytometry: P = 0.0058). After application of 600 mOsm/L saline, DC morphology was unchanged, although the percentage of fragmented DCs, and phenotypic expression of CD86 (immunofluorescence: P < 0.0001; and flow cytometry: P = 0.003) and CD68 (immunofluorescence: P = 0.024) were higher compared to 350 mOsm/L controls.ConclusionsShort-term exposure to mild hyperosmolar saline (450 mOsm/L) induced morphological and phenotypic maturation in corneal epithelial DCs. More severe hyperosmolar insult (600 mOsm/L) for 2 hours appeared toxic to these cells. These data suggest that hyperosmolar conditions activate corneal DCs, which may have implications for understanding DC activation in DED.

Inflamacija disajnih puteva kod pacijenata sa bronhiektazijama

Bronchiectasis is a chronic lung disease characterized by an abnormal dilation of the bronchial lumen caused by weakening or destruction of the muscle or elastic components of the bronchial wall, decreased mucous clearance and frequent infections of the respiratory tract. The golden standard for bronchiectasis diagnosis is high-resolution computed tomography (HRCT) of the chest. Inflammation holds a central role in the development of structural lung changes, as well as airway and lung parenchyma damage. Infection and colonization of the respiratory tract contribute to increased inflammation and further damage to the lung. Upon entry into the respiratory tract, the pathogens activate epithelial cells, macrophages and dendritic cells. Activated inflammatory cells secrete chemical mediators which activate the immune response and thus allow the phagocytosis of pathogens. Early diagnosis, appropriate treatment and interruption of the vicious circle between infection and inflammation in patients suffering from bronchiectasis, prevent the development of structural changes to the airways.

The Relationship Between Corneal Nerve Density and Hemoglobin A1c in Patients With Prediabetes and Type 2 Diabetes.

PurposeDecreased corneal nerve fiber density and higher corneal epithelial dendritic cells have been reported in established patients with type 2 diabetes; however, alterations in the subbasal nerve plexus in prediabetes with healthy subjects or subjects with diabetes is limited. The study aimed to determine corneal nerve fiber density and morphology and dendritic cell density between healthy subjects and those with prediabetes or type 2 diabetes.MethodsFifty-two subjects (aged 30–70 years) were recruited. Blood samples and body metrics were taken. Subjects were grouped as: healthy controls (hemoglobin A1c [HbA1c] < 5.7%), prediabetes (5.7–6.4%), and type 2 diabetes (> 6.4% or physician diagnosis). Central corneal subbasal nerve plexus was imaged using in vivo confocal microscopy. Corneal nerve fiber density and morphology, including interconnections and tortuosity, and dendritic cell density were assessed. Kruskal-Wallis tests were carried out to compare differences in the examined variables between groups. Spearman correlations were carried out to examine the associations between body metrics with HbA1c and corneal findings.ResultsSeventeen healthy controls, 20 subjects with prediabetes, and 15 subjects with type 2 diabetes completed this study. Central corneal nerve fiber density was significantly lower in type 2 diabetes compared to prediabetes (P = 0.045) and healthy controls (P = 0.001). No differences were found in central corneal nerve fiber interconnections, tortuosity, or dendritic cell density between groups. There was a significant association between HbA1c and corneal nerve fiber density (rho = −0.45, P = 0.001) and body mass index (BMI; rho = −0.30, P = 0.04).ConclusionsIncreased HbA1c values are associated with decreased corneal nerve fiber density across the spectrum of type 2 diabetes.

Corneal epithelial dendritic cells in patients with multiple sclerosis: An in vivo confocal microscopy study

PurposeTo evaluate density and morphology of corneal epithelial dendritic cells (DCs) in patients with multiple sclerosis (MS) using in vivo confocal microscopy (IVCM). MethodsThis was a single-center cross-sectional comparative study. All MS patients were clinically scored using the Expanded Disability Status Scale (EDSS) score. Patients underwent ophthalmological examination and then cornea was analyzed by IVCM Heidelberg Retina Tomograph (HRT 3) in combination with Rostock Cornea Module and CCD camera. Five sectors (central, nasal, temporal, inferior, superior and central area) were analyzed in both patient eyes, then for each sector one image was selected and analyzed by using the manual cell counting system offered with the software and ImageJ program. DCs density (cell/mm2) and DCs size (µm2) were considered for the analyses. Difference between the two groups and correlation between DCs, MS type, EDSS score, optic neuritis and ongoing therapy were analyzed. ResultsWe enrolled 46 consecutive patients: 23 with MS (age 47.87 ± 7.22 years (mean ± standard deviation) and 21 healthy subjects (age 46.0 ± 12.6 years) from July 2017 to July 2018. MS patients showed a lower DCs density when compared with healthy subjects (p < 0.05). Moreover, we found a direct correlation (r:0.48, p < 0.05) between DCs density and ongoing disease-modifying therapy. ConclusionIVCM was able to show a difference in corneal DCs density between MS patients and healthy subjects, providing an insight to the underlying changes of the clinical manifestations of MS. Further studies are needed to provide evidence of possible clinical implications.

Novel alterations in corneal neuroimmune phenotypes in mice with central nervous system tauopathy

BackgroundTauopathy in the central nervous system (CNS) is a histopathological hallmark of frontotemporal dementia (FTD) and Alzheimer’s disease (AD). Although AD is accompanied by various ocular changes, the effects of tauopathy on the integrity of the cornea, which is densely innervated by the peripheral nervous system and is populated by resident dendritic cells, is still unknown. The aim of this study was to investigate if neuroimmune interactions in the cornea are affected by CNS tauopathy.MethodsCorneas from wild type (WT) and transgenic rTg4510 mice that express the P301L tau mutation were examined at 2, 6, 8, and 11 months. Clinical assessment of the anterior segment of the eye was performed using spectral domain optical coherence tomography. The density of the corneal epithelial sensory nerves and the number and field area of resident epithelial dendritic cells were assessed using immunofluorescence. The immunological activation state of corneal and splenic dendritic cells was examined using flow cytometry and compared between the two genotypes at 9 months of age.ResultsCompared to age-matched WT mice, rTg4510 mice had a significantly lower density of corneal nerve axons at both 8 and 11 months of age. Corneal nerves in rTg4510 mice also displayed a higher percentage of beaded nerve axons and a lower density of epithelial dendritic cells compared to WT mice. From 6 months of age, the size of the corneal dendritic cells was significantly smaller in rTg4510 compared to WT mice. Phenotypic characterization by flow cytometry demonstrated an activated state of dendritic cells (CD86+ and CD45+ CD11b+CD11c+) in the corneas of rTg4510 compared to WT mice, with no distinct changes in the spleen monocytes/dendritic cells. At 2 months of age, there were no significant differences in the neural or immune structures between the two genotypes.ConclusionsCorneal sensory nerves and epithelial dendritic cells were altered in the rTg4510 mouse model of tauopathy, with temporal changes observed with aging. The activation of corneal dendritic cells prior to the gradual loss of neighboring sensory nerves suggests an early involvement of corneal immune cells in tau-associated pathology originating in the CNS.

Density and Morphology of Corneal Epithelial Dendritic Cells are Different in Allergy

ABSTRACTPurpose: The role of corneal epithelial dendritic cells (CEDC), a subtype of antigen presenting cells, in ocular allergy remains largely unknown. This cross-sectional study evaluated the density and morphology of CEDC in participants diagnosed with systemic allergy, to increase our understanding of the role of CEDC in ocular inflammation associated with systemic allergy.Materials and methods: A convenience sample of 50 participants was categorised into allergic and non-allergic groups (31 allergic and 19 non-allergic) based on the results of skin prick test (SPT). Ocular allergy symptoms, clinical ocular surface signs and serum IgE were assessed. In vivo confocal microscopy was performed on the right eye only. The number of CEDC in a 1mm2 region at both the central and mid-peripheral cornea was manually counted. CEDC morphology was graded on a 1 to 3 scale.Results: Ocular surface symptoms, signs (other than eyelid oedema), and serum IgE were significantly higher in the allergic (SPT+) group. CEDC density at the mid-peripheral cornea was significantly lower in the allergic group (p = .003). CEDC morphology grades were significantly higher in allergic participants in the central cornea (p = .02), with the highest grade morphology observed only in allergic participants. No associations were evident between CEDC density or morphology and ocular signs, symptoms or serum IgE.Conclusions: The study showed reduced CEDC density and cells with longer dendrites in allergic participants. The more mature CEDC morphology in the allergic group is suggestive of an inflammatory or immune response.

Extracellular Vesicles: A New Nano Tool for the Treatment of Inflammatory Bowel Diseases

The intestinal tract is a complex and important physiological and immunological organ. Intestinal tract homeostasis requires a series of coordinated interactions involving gut microbiota, the crypt intestinal stem cells (ISC) and the surrounding niche, including the intestinal epithelial cells, endothelial cells, dendritic cells, and macrophages. The destruction of intestinal homeostasis leads to autoimmune diseases, such as inflammatory bowel disease (IBD). IBD is a non-specific, and remittent- relapsing inflammatory disorder of the gastrointestinal tract. There is no effective method to keep patients in remission for a long term. It has been reported that extracellular vesicles (EVs) exert immune activation and immunosuppressive effects in the pathogenesis of IBD. In order to explore new therapeutic strategies for IBD, in this review, we summarize the observations on the immune properties and functions of EVs in intestinal mucosal immunity.

Study on the correlation between small intestinal dendritic cells and non-alcoholic fatty liver disease in mice

Objective: To preliminary, explore the effect of small intestinal epithelial dendritic cells on the occurrence and development of nonalcoholic fatty liver disease in mice. Methods: Thirty-two (half male and half female) 4-week-old C57BL/6 mice were randomly divided into two groups. The mice were fed with normal diet (SD group) and high-fat diet (HFD group). Eight mice (half male and half female) were randomly killed from each group over the 14 and 20-weeks feeding period to observe their body weight, liver and small-intestine wet weight. Alanine aminotransferase, aspartate aminotransferase, blood glucose, high-density lipoprotein, low-density lipoprotein, total cholesterol and triglyceride were determined by eyeball blood samples. Pathological diagnosis and alcoholic fatty liver disease activity score were collected. The number of mice small intestinal dendritic cells was observed under a microscope. Statistical analysis was performed to compare two groups of independent samples with homogeneity test of variance, t test, and covariance analysis. Results: The body weight, liver wet weight, serum alanine aminotransferase and aspartate aminotransferase of mice in HFD group were significantly higher than those of control group at 20 weeks (P < 0.05), and the serum high density lipoprotein of mice in HFD group was significantly higher than that of SD group at 14 weeks (P < 0.05). At 14th weeks, the liver tissue of mice in HFD group had early pathological manifestations of hepatitis (fatty degeneration, punctate necrosis and balloon-like degeneration). Of which 87.5% (7/8) of them were diagnosed as non-alcoholic steatohepatitis or non-alcoholic fatty liver disease, while only a few mice in SD group had early pathological manifestations of hepatitis. At 20th weeks, all mice in HFD group were diagnosed with non-alcoholic steatohepatitis or non-alcoholic fatty liver disease, while none of the mice in SD group was diagnosed with non-alcoholic fatty liver disease. At both time points, the percentage of small intestinal dendritic cells in HFD group was significantly higher than that in SD group (14 weeks: 4.181 ± 4.314 vs. 15.099 ± 10.349; 20 weeks: 9.615 ± 8.267 vs. 32.839 ± 24.475, both P < 0.05). Statistical analysis combined with the alcoholic fatty liver disease activity score showed that there was no linear correlation between the two groups (regression coefficient was 20.196%). Conclusion: The number and different staging of small intestinal dendritic cells in mice is associated with the occurrence and development of NAFLD.

Corneal epithelial dendritic cell density in the healthy human cornea: A meta-analysis of in-vivo confocal microscopy data

PurposeNumerous studies have reported a wide range of corneal epithelial dendritic cells (CEDC) density using in-vivo confocal microscopy in healthy participants. It is necessary to establish normal CEDC values for healthy corneas to enable differentiation from pathological corneas. This meta-analysis aimed to establish CEDC density and distribution and examine their relationship with age and sex. MethodsA systematic review of the literature of studies using the Heidelberg Retinal Tomograph with Rostock Corneal Module and reporting CEDC density in healthy subjects up to December 2018 was conducted via Medline, Google Scholar, Scopus, PubMed, Embase and Cochrane library. A random effect modeling approach was used to obtain the results of meta-analysis and meta-regression was conducted to estimate the effect of age and sex. Results38 studies reported central and 9 reported peripheral inferior CEDC density of 1203 participants (mean age 46.0 ± 12.2, range 18–81 years). CEDC density in the central and peripheral inferior cornea was 26.4 ± 13.6 cells/mm2 (95% CI:22.5–26.8) and 74.9 ± 22.7 cells/mm2 (95%CI:59.8–90.0), respectively. No effect of age was found on central CEDC density (p = 0.63); whereas peripheral CEDC density decreased with increasing age (p = 0.02). CEDC density was not influenced by sex at either location (p > 0.48). ConclusionThis study established that the density at the peripheral inferior cornea is three-fold higher than at the central cornea. Peripheral but not central CEDC density decreased with increasing age. There are limited studies in youth (<18 years), precluding a more detailed analysis. Sex does not appear to be a significant factor in CEDC density.

The Effects of Aging on Corneal and Ocular Surface Homeostasis in Mice.

Aging is a risk factor for dry eye disease. The aim of this study was to investigate if aging is associated with a range of signs of dry eye disease, including tear hyperosmolarity, reduced nerve density, and increased dendritic cell number, in mice. Healthy C57BL/6 female mice, aged 2 months (young, n = 10) and 22 months (aged, n = 11) were used. Clinical assessments included corneal sensitivity (Cochet-Bonnet esthesiometry), tear secretion (Phenol red thread test), tear film osmolarity (TearLab osmometer), and corneal thickness (optical coherence tomography). The sum length of the corneal superficial terminals and sub-basal nerves, density of vertical nerve projections, and density and tree area of resident epithelial dendritic cells, were assessed using immunofluorescence and confocal microscopy. Aged mice had significantly higher tear secretion, lower corneal sensitivity, and a thicker corneal stroma but thinner epithelium. There was no significant intergroup difference for tear osmolarity. Aged mice showed a significantly lower sum length of nerves in the superficial terminals and sub-basal plexus, relative to young mice. Dendritic cell density and morphology were similar in both groups. In mice, aging is associated with higher tear secretion and corneal epithelial thinning, together with lower corneal nerve density and sensitivity. However, aging was not significantly associated with changes to tear osmolarity or dendritic cell density or size, despite a significant reduction in total nerve length. These findings demonstrate that aged mice exhibit some changes to ocular surface parameters that parallel the anomalies evident in dry eye disease.

Effect of age and contact lens wear on corneal epithelial dendritic cell distribution, density, and morphology

PurposeContact lens wearers aged 15–25 years are at higher risk of corneal inflammation, yet little is known about corneal inflammatory state in this group. Previous investigations show density of corneal epithelial dendritic cells (CEDC) may increase with contact lens wear. However, it is not known how corneal distribution or morphology of CEDC alters with lens wear or whether these markers are affected by age. This study characterised CEDC in adolescent and young adult contact lens wearers to determine effects of contact lens wear and age on CEDC density, distribution and morphology. MethodForty participants (20 contact lens wearers, 20 healthy non-wearers; age 16–36 years; 16M:24F) completed this pilot study. Corneal images were captured using in vivo confocal microscopy (HRTII, Rostock). CEDC were manually counted in a 1 mm2 area of the central and mid-peripheral cornea, and ratio of central to midperipheral density was calculated. CEDC morphology and dendrite length were graded. Differences between groups and between regions, and associations with age were examined. Significance was determined at P < 0.05. ResultsA lower ratio of central to mid-peripheral CEDC density was found with younger age (ρ = 0.42, P = 0.01). CEDC morphology was not associated with age or contact lens wear. CEDC density in the mid-peripheral cornea was higher in soft lens wearers than non-wearers (P = 0.04), but central density did not differ. CEDC density and morphology were not significantly different between centre (median density 11 cells/mm2, range 0–120) and mid-periphery (10 cells/mm2, 0–58). ConclusionDensity, distribution and morphology of CEDC do not differ in established contact lens wearers. A relatively lower density of CEDC in the central cornea of younger patients may allude to a more naive immune status in this group and warrants further study. Decreased central CEDC density identified in orthokeratology lens wear requires confirmation in a larger group.

Clinical changes of contralateral unaffected eyes in patients with unilateral infectious keratitis under in vivo confocal microscopy

Objective To evaluate the clinical changes of corneal epithelial cells, dendritic cells, endothelial cells and corneal nerves in contralateral eyes of patients with unilateral infectious keratitis. Methods A prospective serial case observation study was conducted in patients with unilateral infectious keratitis from January to August 2018 in the First Affiliated Hospital of Harbin Medical University.The corneal epithelial cells density, dendritic cells density, endothelial cells density, total nerve density, total number of nerves and branch nerve density were analyzed with in vivo confocal microscopy (IVCM), slit lamp microscopy was performed on all subjects to observe the conjunctiva, cornea and anterior chamber.Corneal branch nerve density and total nerve density were compared with the control group by homogeneity test of variance.This study was approved by the Ethics Committee of the First Affiliated Hospital of Harbin Medical University (No.IRB-AF/SC-04/01.0). Results Slit lamp microscopy showed no significant changes in anterior segment of the contralateral uninfected eyes in the 3 groups.The corneal epithelial cells density of uninfected eyes in viral keratitis group, bacterial keratitis group and fungal keratitis group was 1 834(1 584, 2 107), 1 905(1 651, 2 332) and 1 859(1 477, 1 995)/mm2, respectively, which were significantly lower than 3 479(3 080, 3 910)/mm2 in the control group, the dendritic cells densities in viral keratitis group and bacterial keratitis group were 175(139, 214)/mm2 and 156(118, 190)/mm2, which were higher than 69(57, 76)/mm2 in the control group, the differences were statistically significant (all at P<0.05). The corneal endothelial cells density of uninfected eyes in viral keratitis group was 1 107(945, 1 270)/mm2, which was less than 1 905(1 651, 2 332)/mm2 in the bacterial keratitis group and 1 859(1 477, 1 995)/mm2 in the fungal keratitis group (both at P<0.05). The corneal nerve number and total nerve density of uninfected eyes in viral keratitis group were 10(7, 11)/mm2 and (1 822.85±622.34)μm/mm2, which were lower than 11(9, 13)/mm2 and (2 340.91±408.70)μm/mm2 in the bacterial keratitis group, with significant differences between them (P<0.05, P<0.008 3). The morphology of corneal epithelial cells and endothelial cells in each infectious keratitis group was larger than that in the control group, while the morphology and number of dendritic cells in the contralateral eye of patients with viral and bacterial keratitis increased. Conclusions In unilateral uninfected eyes of infectious keratitis, the density of corneal epithelial cells, dendritic cells, endothelial cells and corneal nerves changes correspondingly.There may be a close relationship of corneal immunity and nervous system between the two eyes. Key words: Infectious keratitis; In vivo confocal microscopy; Corneal epithelial cells; Dendritic cells; Corneal nerve density; Corneal endothelial cells

Knowing thyself: an audit of cell therapy manufacturing in Australia and New Zealand

Background & Aim We conducted a survey to assess cell therapy manufacturing capacity in Australia and New Zealand. We examined the number and types of cell therapy manufacturing facilities; the number of projects, parallel processes and clinical trials; the types of products; and manufacturing and quality staffing levels. We identified participant cell therapy manufacturing facilities by contacting individuals working in the field of cell therapy in Australia and New Zealand and inviting submissions on a one per cell manufacturing facility basis. Methods, Results & Conclusion The overall response rate was 59% (23 of 38 eligible facilities). Of the 23 responding facilities, 21 are in Australia and 2 are in New Zealand. Eighteen are run by public organisations and five by private organisations and a diverse range of accreditations were represented. There were 43 GMP laboratories across 14 of 22 facilities that reported on this parameter and approximately 4.6 manufacturing staff and 1.7 quality staff per facility. Products included hematopoietic progenitor cells, mononuclear cells, T-cells, peripheral blood mononuclear cells, CD34+ cells, mesenchymal stem cells and chimeric antigen receptor T-cells, therapeutic T-cell subsets, cell banks, autologous serum eye drops, keratinocytes, human amnion epithelial cells, pancreatic islets, dendritic cells and chondrocytes. Research interests were processing and storage optimization; the effect of methodologies on engraftment; gene and cell therapy; the biology of manufactured cell types; cell tracking and imaging; cell culture platforms; bioscaffolds; 3-D bioprinting; transplantation and the diseases treated. Reported collaborations included within Australia and with groups in Basel, Busan, Boston, Cambridge MA, Hong Kong, Los Angeles, Montreal, Nagoya, New York, Philadelphia, Stockholm and Toronto. Other national manufacturing-relevant assets are the Centre of Research Excellence in MedTech in New Zealand, the Cooperative Research Centre for Cell Therapy Manufacturing in Australia, the Australian National Health and Medical Research Council Clinical Trials Centre and Advanced Health Research and Translation Centres and Therapeutic Innovation Australia. Australian and New Zealand provide a platform for cell therapy manufacturing, infrastructure and capacity building. These form the foundation to enable both countries to meet the growing need for cell and gene therapy and regenerative medicine in our region.