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Background: To evaluate the efficacy of corneal tattooing for various clinical applications., Methods: The medical charts of 62 eyes of 62 patients who underwent corneal tattooing between March 2016 and August 2017 were retrospectively reviewed. The causes of opacity and various methods of corneal tattooing were analyzed., Results: Among our 62 patients, 38 were males and 24 were females. Average age was 48.47 ± 15.30 (range, 12-74) years old. The mean follow-up period was 40.19 ± 2.34 (range, 36-43) months. The most common causes of corneal opacity were ocular trauma (33 eyes, 53.2%), prior retinal surgery (9 eyes, 14.5%), congenital etiologies (8 eyes, 12.9%) and measles (5 eyes, 8.0%). The most common associated ocular findings were strabismus (23 eyes, 37.0%), phthisis bulbi (17 eyes, 27.4%) and band keratopathy (13 eyes, 20.9%). Cosmetic outcomes improved without serious complications in all cases., Conclusions: Corneal tattooing is a viable option with an expanding set of indications, such as discolored previous corneal tattoos, white pupil due to inoperable cataract with clear cornea and dense corneal opacities in blind eyes. Elective corneal tattooing seems to be a viable and convenient method to improve cosmesis with minimal complications and high patient satisfaction.

Effective activation of macrophages through phagocytic Fcγ receptors (FcγR) has been shown to require selenoprotein K (Selk). We set out to determine whether the FcγR-mediated uptake process itself also requires Selk and potential underlying mechanisms. Macrophages from Selk knockout (KO) mice were less efficient compared with wild-type (WT) controls in engulfing IgG-coated fluorescent beads. Using LC-MS/MS to screen for Selk-binding partners involved in FcγR-mediated phagocytosis, we identified Arf-GAP with SH3 domain, ANK repeat, and PH domain-containing protein 2 (ASAP2). Coimmunoprecipitation assays confirmed interactions between Selk and ASAP2. Selk was required for ASAP2 to be cleaved by calpain-2 within the Bin/Amphiphysin/Rvs (BAR) domain of ASAP2. BAR domains promote membrane association, which was consistent with our data showing that Selk deficiency led to retention of ASAP2 within the phagocytic cup. Because Selk was recently identified as a cofactor for the palmitoylation of certain proteins, we investigated whether ASAP2 was palmitoylated and whether this was related to its cleavage by calpain-2. Acyl/biotin exchange assays and MALDI-TOF analysis showed that cysteine-86 in ASAP2 was palmitoylated in WT, but to a much lesser extent in KO, mouse macrophages. Inhibitors of either palmitoylation or calpain-2 cleavage and rescue experiments with different versions of Selk demonstrated that Selk-dependent palmitoylation of ASAP2 leads to cleavage by calpain-2 within the BAR domain, which releases this protein from the maturing phagocytic cup. Overall, these findings identify ASAP2 as a new target of Selk-dependent palmitoylation and reveal a new mechanism regulating the efficiency of FcγR-mediated phagocytosis., (© Society for Leukocyte Biology.)

Purpose: To describe a standardized flood-illuminated adaptive optics (AO) imaging protocol suitable for the clinical setting and to assess sampling methods for measuring cone density., Methods: Cone density was calculated following three measurement protocols: 50 × 50-μm sampling window values every 0.5° along the horizontal and vertical meridians (fixed-interval method), the mean density of expanding 0.5°-wide arcuate areas in the nasal, temporal, superior, and inferior quadrants (arcuate mean method), and the peak cone density of a 50 × 50-μm sampling window within expanding arcuate areas near the meridian (peak density method). Repeated imaging was performed in nine subjects to determine intersession repeatability of cone density., Results: Cone density montages could be created for 67 of the 74 subjects. Image quality was determined to be adequate for automated cone counting for 35 (52%) of the 67 subjects. We found that cone density varied with different sampling methods and regions tested. In the nasal and temporal quadrants, peak density most closely resembled histological data, whereas the arcuate mean and fixed-interval methods tended to underestimate the density compared with histological data. However, in the inferior and superior quadrants, arcuate mean and fixed-interval methods most closely matched histological data, whereas the peak density method overestimated cone density compared with histological data. Intersession repeatability testing showed that repeatability was greatest when sampling by arcuate mean and lowest when sampling by fixed interval., Conclusions: We show that different methods of sampling can significantly affect cone density measurements. Therefore, care must be taken when interpreting cone density results, even in a normal population.

The aim of this study was to assess the feasibility of using a commercially available high-resolution adaptive optics (AO) camera to image the cone mosaic in Japanese macaques (Macaca fuscata) with dominantly inherited drusen. The macaques examined develop drusen closely resembling those seen in humans with age-related macular degeneration (AMD). For each animal, we acquired and processed images from the AO camera, montaged the results into a composite image, applied custom cone-counting software to detect individual cone photoreceptors, and created a cone density map of the macular region. We conclude that flood-illuminated AO provides a promising method of visualizing the cone mosaic in nonhuman primates. Future studies will quantify the longitudinal change in the cone mosaic and its relationship to the severity of drusen in these animals.

Immune complexes composed of IgG-opsonized pathogens, particles, or proteins are phagocytosed by macrophages through Fcγ receptors (FcγRs). Macrophages primed with IFNγ or other pro-inflammatory mediators respond to FcγR engagement by secreting high levels of cytokines and nitric oxide (NO). We found that unprimed macrophages produced lower levels of NO, which required efficient calcium (Ca(2+)) flux as demonstrated by using macrophages lacking selenoprotein K, which is required for FcγR-induced Ca(2+) flux. Thus, we further investigated the signaling pathways involved in low output NO and its functional significance. Evaluation of inducible, endothelial, and neuronal nitric-oxide synthases (iNOS, eNOS, and nNOS) revealed that FcγR stimulation in unprimed macrophages caused a marked Ca(2+)-dependent increase in both total and phosphorylated nNOS and slightly elevated levels of phosphorylated eNOS. Also activated were three MAP kinases, ERK, JNK, and p38, of which ERK activation was highly dependent on Ca(2+) flux. Inhibition of ERK reduced both nNOS activation and NO secretion. Finally, Transwell experiments showed that FcγR-induced NO functioned to increase the phagocytic capacity of other macrophages and required both NOS and ERK activity. The production of NO by macrophages is conventionally attributed to iNOS, but we have revealed an iNOS-independent receptor/enzyme system in unprimed macrophages that produces low output NO. Under these conditions, FcγR engagement relies on Ca(2+)-dependent ERK phosphorylation, which in turn increases nNOS and, to a lesser extent, eNOS, both of which produce low levels of NO that function to promote phagocytosis.