Depletion of the Insulator Protein CTCF Results in Herpes Simplex Virus 1 Reactivation In Vivo.

Herpes simplex virus 1 (HSV-1) establishes a lifelong latent infection in host peripheral neurons, including the neurons of the trigeminal ganglia (TG). HSV-1 can reactivate from neurons to cause recurrent infection. During latency, the insulator protein CTCF occupies DNA binding sites on the HSV-1 genome, and these sites have been previously characterized as functional enhancer-blocking insulators. Previously, CTCF was found to be dissociated from wild-type virus postreactivation but not in mutants that do not reactivate, indicating that CTCF eviction may also be an important component of reactivation. To further elucidate the role of CTCF in reactivation of HSV-1, we used recombinant adeno-associated virus (rAAV) vectors to deliver a small interfering RNA targeting CTCF to peripheral neurons latent with HSV-1 in rabbit TG. Our data show that CTCF depletion resulted in long-term and persistent shedding of infectious virus in the cornea and increased ICP0 expression in the ganglia, indicating that CTCF depletion facilitates HSV-1 reactivation.IMPORTANCE Increasing evidence has shown that the insulator protein CTCF regulates gene expression of DNA viruses, including the gammaherpesviruses. While CTCF occupation and insulator function control gene expression in DNA viruses, CTCF eviction has been correlated to increased lytic gene expression and the dissolution of transcriptional domains. Our previous data have shown that in the alphaherpesvirus HSV-1, CTCF was found to be dissociated from the HSV-1 genome postreactivation, further indicating a global role for CTCF eviction in the transition from latency to reactivation in HSV-1 genomes. Using an rAAV8, we targeted HSV-1-infected peripheral neurons for CTCF depletion to show that CTCF depletion precedes the shedding of infectious virus and increased lytic gene expression in vivo, providing the first evidence that CTCF depletion facilitates HSV-1 reactivation.

A Retrospective Comparison of Phaco-tube vs. Phaco-trabeculectomy in Glaucoma Patients.

PURPOSE: To compare surgical outcomes of phacoemulsification combined with Baerveldt implantation (phaco-tube) or trabeculectomy with mitomycin-C (MMC) (phaco-trab) in patients without prior incisional ocular surgery. DESIGN: Single-center, retrospective, comparative case series. PARTICIPANTS: A total of 90 patients underwent surgical treatment, including 45 patients in the phaco-tube group and 45 patients in the phaco-trab group. METHODS: Eligible patients were identified using current procedural terminology (CPT) codes, and their medical records were retrospectively reviewed. MAIN OUTCOME MEASURES: The primary outcome measure was the rate of surgical failure (IOP ≤5 mmHg or >21 mmHg or reduced <20% from baseline on 2 consecutive study visits after 3 months, reoperations for glaucoma, or experienced loss of light perception vision). Patients who had successful surgical outcomes without use of glaucoma medications were classified as complete successes, while those who used glaucoma medications were classified as qualified successes. Secondary outcome measures were visual acuity (VA), visual field mean deviation (VFMD), intraocular pressure (IOP), glaucoma medication use, and complications. RESULTS: The cumulative probability of failure was 6.7% in the phaco-tube group and 32.8% in the phaco-trab group after 3 years (P = 0.005; Restricted Mean Survival Time = 5.9 months, 95% CI = 1.4-10.4 months). The IOP was 13.1 ± 3.4 mmHg in the phaco-tube group and 13.3 ± 6.2 mmHg in the phaco-trab group at 3 years (P = 0.90), and the number of glaucoma medications was 2.6 ± 1.5 in the phaco-tube group and 1.7 ± 1.3 in the phaco-trab group (P = 0.015). The logarithm of the minimum angle of resolution VA was 0.39 ± 0.58 in the phaco-tube group and 0.43 ± 0.73 in the phaco-trab group at 3 years (P = 0.82), and VFMD was -18.3 ± 9.0 dB in the phaco-tube group and -14.1 ± 7.0 dB in the phaco-trab group (P = 0.16). Postoperative complications developed in 21 patients (47%) in the phaco-tube group and 15 patients (33%) in the phaco-trab group (P = 0.28). CONCLUSIONS: Phaco-tubes had a significantly lower rate of surgical failure compared to phaco-trabs after 3 years of follow-up. However, phaco-trabs used significantly fewer glaucoma medications at multiple postoperative timepoints and had a higher proportion of complete success. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Clinical Features and Treatment Outcomes of Carbapenem-Resistant Pseudomonas aeruginosa Keratitis.

Importance: Evaluation of the microbiological diagnostic profile of multidrug-resistant Pseudomonas aeruginosa keratitis and potential management with rose bengal-photodynamic antimicrobial therapy (RB-PDAT) is important. Objective: To document the disease progression of carbapenemase-resistant P aeruginosa keratitis after an artificial tear contamination outbreak. Design, Setting, and Participants: This retrospective observation case series included 9 patients 40 years or older who presented at Bascom Palmer Eye Institute and had positive test results for multidrug-resistant P aeruginosa keratitis between January 1, 2022, and October 31, 2023. Main Outcomes and Measures: Evaluation of type III secretion phenotype, carbapenemase-resistance genes blaGES and blaVIM susceptibility to antibiotics, and in vitro and in vivo outcomes of RB-PDAT against multidrug-resistant P aeruginosa keratitis. Results: Among the 9 patients included in the analysis (5 women and 4 men; mean [SD] age, 73.4 [14.0] years), all samples tested positive for exoU and carbapenemase-resistant blaVIM and blaGES genes. Additionally, isolates were resistant to carbapenems as indicated by minimum inhibitory concentration testing. In vitro efficacy of RB-PDAT indicated its potential application for treating recalcitrant cases. These cases highlight the rapid progression and challenging management of multidrug-resistant P aeruginosa. Two patients were treated with RB-PDAT as an adjuvant to antibiotic therapy and had improved visual outcomes. Conclusions and Relevance: This case series highlights the concerning progression in resistance and virulence of P aeruginosa and emphasizes the need to explore alternative therapies like RB-PDAT that have broad coverage and no known antibiotic resistance. The findings support further investigation into the potential effects of RB-PDAT for other multidrug-resistant microbes.