Association of Anti–Herpes Simplex Virus IgG in Tears and Serum With Clinical Presentation in Patients With Presumed Herpetic Simplex Keratitis

CLEAR - Contact lens technologies of the future

Contact lenses in the future will likely have functions other than correction of refractive error. Lenses designed to control the development of myopia are already commercially available. Contact lenses as drug delivery devices and powered through advancements in nanotechnology will open up further opportunities for unique uses of contact lenses. This review examines the use, or potential use, of contact lenses aside from their role to correct refractive error. Contact lenses can be used to detect systemic and ocular surface diseases, treat and manage various ocular conditions and as devices that can correct presbyopia, control the development of myopia or be used for augmented vision. There is also discussion of new developments in contact lens packaging and storage cases. The use of contact lenses as devices to detect systemic disease has mostly focussed on detecting changes to glucose levels in tears for monitoring diabetic control. Glucose can be detected using changes in colour, fluorescence or generation of electric signals by embedded sensors such as boronic acid, concanavalin A or glucose oxidase. Contact lenses that have gained regulatory approval can measure changes in intraocular pressure to monitor glaucoma by measuring small changes in corneal shape. Challenges include integrating sensors into contact lenses and detecting the signals generated. Various techniques are used to optimise uptake and release of the drugs to the ocular surface to treat diseases such as dry eye, glaucoma, infection and allergy. Contact lenses that either mechanically or electronically change their shape are being investigated for the management of presbyopia. Contact lenses that slow the development of myopia are based upon incorporating concentric rings of plus power, peripheral optical zone(s) with add power or non-monotonic variations in power. Various forms of these lenses have shown a reduction in myopia in clinical trials and are available in various markets.

Two Potential Clinical Applications of Origami-Based Paper Devices

Detecting small amounts of analyte in clinical practice is challenging because of deficiencies in specimen sample availability and unsuitable sampling environments that prevent reliable sampling. Paper-based analytical devices (PADs) have successfully been used to detect ultralow amounts of analyte, and origami-based PADs (O-PADs) offer advantages that may boost the overall potential of PADs in general. In this study, we investigated two potential clinical applications for O-PADs. The first O-PAD we investigated was an origami-based enzyme-linked immunosorbent assay (ELISA) system designed to detect different concentrations of rabbit IgG. This device was designed with four wing structures, each of which acted as a reagent loading zone for pre-loading ELISA reagents, and a central test sample loading zone. Because this device has a low limit of detection (LOD), it may be suitable for detecting IgG levels in tears from patients with a suspected viral infection (such as herpes simplex virus (HSV)). The second O-PAD we investigated was designed to detect paraquat levels to determine potential poisoning. To use this device, we sequentially folded each of two separate reagent zones, one preloaded with NaOH and one preloaded with ascorbic acid (AA), over the central test zone, and added 8 µL of sample that then flowed through each reagent zone and onto the central test zone. The device was then unfolded to read the results on the test zone. The three folded layers of paper provided a moist environment not achievable with conventional paper-based ELISA. Both O-PADs were convenient to use because reagents were preloaded, and results could be observed and analyzed with image analysis software. O-PADs expand the testing capacity of simpler PADs while leveraging their characteristic advantages of convenience, cost, and ease of use, particularly for point-of-care diagnosis.

Pathological consequences of anti-citrullinated protein antibodies in tear fluid and therapeutic potential of pooled human immune globulin-eye drops in dry eye disease

PURPOSE

To investigate the role of Anti-Citrullinated Protein autoantibodies (ACPAs) in the pathology of dry eye disease (DED) and the therapeutic potential of pooled human immune globulin-eye drops in these patients.

METHODS

We investigated the presence of citrullinated proteins and ACPAs in ocular surface wash (OSW) and conjunctival impressions from patients with DED and determined the pathological consequences of OSW with high ACPA using in vitro experiments and in vivo murine models. We performed a randomized, double-masked, pilot clinical trial to determine the safety, tolerability and preliminary efficacy of using pooled human immune globulin-eye drops to treat DED patients with ACPAs in OSW.

RESULTS

We found that neutrophils are a source of citrullinated proteins on the ocular surface of DED patients. We detected significantly higher immunoglobulin amount and presence of several species of ACPAs in OSW from DED patients. We also found that OSW with high ACPA contributes to production of NETs, and that ACPAs cause ocular surface disease in murine eyes, both of which are reduced with addition of Immune globulins. As compared to Vehicle treatment, pooled human immune globulin-eye drops (IVIG 4 mg/mL) twice a day for 8 weeks caused significant reduction in signs and symptoms of DED with no difference in tolerability or adverse events.

CONCLUSIONS

This is the first report demonstrating ACPAs in OSW of DED patients and their contribution to ocular surface disease. The first-in-human clinical trial suggests that pooled immune globulin-eye drops are a potential new class of biologic therapies for Dry Eye patients.

Herpes simplex virus keratitis: an update of the pathogenesis and current treatment with oral and topical antiviral agents

Ophthalmic herpes simplex viral keratitis is responsible for a range of ocular manifestations from superficial epithelial disease to stromal keratitis and endotheliitis. The Herpetic Eye Disease Study has guided the management of herpetic eye disease for almost twenty years, but newer medications such as valacyclovir are now available and are considered to have better bioavailability than acyclovir. In this review, we examine the existing evidence on the pathogenesis of different ophthalmic herpes simplex viral keratitis disease modalities and the role of oral and topically administered antiviral drugs in the treatment of herpes simplex viral keratitis.

Tear HSV-specific secretory IgA as a potential indicator for recurrent stromal herpes simplex keratitis: a preliminary study

PURPOSE

To assess the herpes simplex virus-specific tear secretory IgA (sIgA) and its correlation with specific serum antibodies and to evaluate the possible value of specific tear sIgA for prediction of herpes simplex keratitis (HSK) recurrence.

METHODS

Tear sIgA and paired serum IgG/IgM/IgA from 41 stromal HSK patients and 15 controls were analyzed by enzyme-linked immunosorbent assay. Subsequent follow-up for monitoring recurrence was performed from the time of first cure on all patients for 4 months to 1 year.

RESULTS

Serum IgG was positive in all participants. The concentration of serum IgA increased with the levels of tear sIgA (P = 0.017). The tear sIgA-positive rate was 36.59% in stromal keratitis, whereas none of the controls were found as sIgA positive. Positivity of sIgA was the only potential factor for predicting the risk of herpes keratitis recurrence (hazard ratio = 9.04; 95% confidence interval, 1.06-77.44; P = 0.045), with a sensitivity of 83.3% and a specificity of 71.4% (P = 0.034; 95% confidence interval, 0.58-0.97). Tear sIgA-positive patients had significantly shorter relapse-free survival compared with tear sIgA-negative patients (P = 0.015).

CONCLUSIONS

This is the first preliminary study suggesting that the levels of tear sIgA could be a potential prognostic parameter for the recurrence of HSK.