UNASSIGNED: Herpes simplex keratitis (HSK) is a blinding disease caused by corneal infection of Herpes simplex virus type 1 (HSV-1). Effective clearance of HSV-1 from the infected cornea is crucial for HSK management. Macrophages play an important part in the innate immune defense against viral infections. This study investigates the immunomodulatory role of NLRP12 in macrophage immune response during HSV-1 infection.
UNASSIGNED: NLRP12 expression post-infection was assessed in various macrophage cell lines. Overexpression of NLRP12 was achieved by lentiviral transfection, and its effect on HSV-1 replication and immune responses were examined. Mechanistic insights into the role of NLRP12 were explored using immunofluorescence and Western Blot. For in vivo studies, ocular adoptive transfer of NLRP12-overexpressing bone marrow derived macrophages (BMDMs) was performed. HSV-1 viral loads, HSK symptoms, and macrophage-mediated immune responses were investigated.
UNASSIGNED: A significant decrease in NLRP12 expression post-infection was observed in various macrophage cell lines. Overexpression of NLRP12 in macrophages reduced HSV-1 replication. Mechanistically, overexpression of NLRP12 triggered early and robust pyroptosis in response to HSV-1 infection, inducing interleukin (IL)-18 production and activating downstream antiviral responses through the JAK-STAT signaling pathway. In vivo, ocular adoptive transfer of NLRP12-overexpressing BMDMs to mouse corneas alleviated HSK damage and reduced HSV-1 viral loads. NLRP12-overexpressing BMDMs improved antiviral responses in the cornea and promoted the maturation of corneal-infiltrating macrophages and dendritic cells. Additionally, NLRP12-overexpressing BMDMs amplified the adaptive immune response in the submandibular draining lymph nodes.
UNASSIGNED: These findings highlight the role of NLRP12 in macrophage-mediated immune response against HSV-1 infection and suggest its potential for possible immunotherapy for HSK.

Herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) are widespread human pathogens that establish chronic latent infections leading to recurrent episodes. Current treatments are limited, necessitating the development of novel antiviral strategies. This study aimed to assess the antiviral efficacy of novel topical formulations containing interferon alpha-2b (IFN α-2b) against HSV-1 and HSV-2. The formulations, Oftalmoferon® forte (eye drops) and Interferon Vaginal Tablets, demonstrated potent antiviral effects against HSV-1 and HSV-2 in Vero cells, respectively, with concentration-dependent inhibition of viral replication. Subsequently, their efficacy was tested in animal models: HSV-1 keratitis in the rabbit eye model and HSV-2 genital herpes in mice. Oftalmoferon® forte effectively treated HSV-1 keratitis, reducing clinical symptoms and ulcerations compared to virus control. Interferon Vaginal Tablets showed promising results in controlling HSV-2 genital herpes in mice, improving survival rates, reducing clinical signs, weight loss and viral replication. The novel IFN α-2b formulations exhibited significant antiviral activity against HSV infections in cell culture and animal models. These findings suggest the potential of these formulations as alternative treatments for HSV infections, particularly in cases resistant to current therapies. Further studies are warranted to optimize treatment regimens and assess clinical efficacy in humans.

UNASSIGNED: Neutrophils are known mediators of innate immunity, yet their effector function in herpesvirus infections remains poorly understood. Here, we elucidate the mechanistic action and pivotal role of neutrophil extracellular traps (NETs) during herpes simplex virus type 1 (HSV-1) ocular infection.
UNASSIGNED: Neutrophils were collected from mice for HSV-1 infection, fluorescence imaging, and immunoblotting assay. Tear samples from healthy subjects and patients with HSV-1 and mice were collected at L. V. Prasad Eye Institute, India, and at the University of Illinois, USA, respectively. For the in vivo study, C57BL/6 mice as well as diversity outbred mice were infected with HSV-1 (McKrae strain) followed by tear fluid collection at various time points (0-10 days). Samples were used for Flow cytometry, ELISA, and immunofluorescence assay. Human transcriptomic profile of keratitis dataset was used evaluate NETosis signaling pathways. We also performed neutrophil depletion studies.
UNASSIGNED: Our data revealed a discernible temporal NET formation (NETosis) predominantly in the infected eye, across normal and diversity outbred murine models and human cases of HSV-1 infection. HSV-1 instigates swift NETosis governed by caspase-1 activation and myeloperoxidase secretion. Distinct accumulations of neutrophils, remaining unengaged in NET release in the contralateral eye post-infection, hinting at a proactive defensive posture in the uninfected eye. Moreover, neutrophil depletion accentuated ocular pathology, augmented viral load, and escalated disease scores, substantiating the protective effects of NETs in curtailing viral replication.
UNASSIGNED: Our report uncovers a previously unexplored mechanism of NETosis through pro-inflammatory cell death in response to ocular HSV-1 infection, and HPSE up-regulation, identifying new avenues for future studies.

Herpes simplex keratitis (HSK) is a blinding disease caused by herpes simplex virus type 1 (HSV-1) infection, and rapid eradication of the virus from the affected cornea is imperative. Nod-like receptors (NLRs) are intracellular innate immune sensors closely associated with cell death, inflammation and immune responses. In this study, we investigated the role of NLRP12 in the antiviral immunology in HSK and the underlying mechanisms. We found that NLRP12 expression was significantly decreased in HSV-1-infected human corneal epithelial cells (HCE-Ts) and HSK mouse corneas. Overexpression of NLRP12 significantly reduced viral replication in infected HCE-Ts and functioned through inflammasome-mediated pyroptosis and downstream IL-18-IFN-γ axis. In HSK mouse models, overexpression of NLRP12 reduced viral replication in the cornea and alleviated HSK symptoms. This resulted from enhanced antiviral immune responses including the activation of specific immune cells in both the cornea and the draining lymph nodes. Specifically, the NLRP12-IL-18-IFN-γ axis regulated the interaction between infected corneal epithelial cells and macrophages. In conclusion, our study identified a role of NLRP12 in mediating pyroptosis and regulating antiviral immune responses. This novel finding opens the possibilities of NLRP12 as a viable target in the therapeutic strategies for HSV-1 infection.

暂无摘要。

Herpes simplex virus type 1 (HSV-1) infection of the eyes results in herpes simplex keratitis (HSK), which has led to vision loss and even blindness in patients. However, the rate of drug resistance in HSV is on the rise; therefore, new antiviral agents with sufficient safety profiles must be developed. At present, we assessed the anti-HSV-1 activity of 502 natural compounds and their ability to reduce the HSV-1-induced cytopathic effect. We chose harmol for further studies because it exhibited the highest antiviral activity. We found that harmol inhibited both HSV-1 F and HSV-1/153 (a clinical drug-resistant strain) replication, with an EC50 of 9.34 µM and 5.84 µM, respectively. Moreover, harmol reduced HSV-1 replication in corneal tissues and viral progeny production in tears, and also alleviated early corneal surface lesions related to HSK. For example, harmol treatment preserved corneal thickness and nerve density in HSK mice. Interestingly, harmol also showed a promising antiviral effect on HSV-1/153 induced HSK in mouse model. Furthermore, harmol combined with acyclovir (ACV) treatment showed a greater antiviral effect than either one alone in vitro. Therefore, harmol may be a promising therapeutic agent for managing HSK.

A group of patients was found to have a special form of recurrent corneal erosion caused by types I and II herpes virus. This form represents an independent form of ophthalmic herpes - herpetic recurrent erosion (HRE) of the cornea. The herpetic etiology of recurrent corneal erosion was confirmed by the immunofluorescence study of scraping from the conjunctiva, which revealed a high concentration of the herpes simplex virus antigen. Treatment of patients (171 patients, 182 eyes) with HRE included 2 consecutive stages: stage I - relief of acute symptoms of the disease with the help of conservative treatment (instillations of interferon inducers, autologous serum, corneal protectors, tear substitutes, use of therapeutic soft contact lenses); in some cases, phototherapeutic keratectomy was used in the absence of the effect of conservative therapy, as well as in the localization of the focus in the optical zone. Stage II involved anti-relapse therapy based on the use of a Russian-produced herpes vaccine in the intercurrent period. After vaccination, observation for 2 years or more showed that 81.3% of patients achieved clinical recovery (complete cessation of HRE recurrences), 15.8% had a decrease in the frequency and severity of relapses, while 2.9% of patients did not respond to the treatment.
Выделена группа пациентов с особой формой рецидивирующей эрозии роговицы, вызванной вирусом герпеса I и II типов, представляющей собой самостоятельную форму офтальмогерпеса — герпетическую рецидивирующую эрозию (ГРЭ) роговицы. Герпетическая этиология рецидивирующей эрозии роговицы подтверждена методом иммунофлуоресцентного исследования соскоба с конъюнктивы, выявившего высокую концентрацию антигена вируса простого герпеса. Лечение пациентов (171 пациент, 182 глаза) с ГРЭ включало 2 последовательных этапа: I этап — купирование острых признаков заболевания с помощью консервативного лечения (инстилляции индукторов интерферона, аутологичной сыворотки, корнеопротекторов, слезозаменителей, применение лечебной мягкой контактной линзы); в отдельных случаях — при отсутствии эффекта консервативной терапии, а также при локализации очага в оптической зоне — прибегали к фототерапевтической кератэктомии. II этап — противорецидивная терапия, основанная на применении отечественной противогерпетической вакцины в межрецидивном периоде. После проведения вакцинации наблюдение в течение 2 лет и более показало, что у 81,3% больных достигнуто клиническое выздоровление (полное прекращение рецидивов ГРЭ), у 15,8% — снижение частоты и тяжести рецидивов, у 2,9% пациентов эффекта не было.

Herpes stromal keratitis is the leading cause of infectious blindness in the western world. Infection by HSV1 is most common, but VZV and hCMV also infect the cornea. Multiple models of HSV1 corneal infection exist, but none for VZV and hCMV because of their host specificity. Here, we used commercially available 3D human corneal epithelial equivalents (HCEE) to study infection by these herpesviruses. HCEE was infected by HSV-1 and hCMV without requiring scarification and resulted in spreading infections. Spread of HSV-1 infection was rapid, while that of hCMV was slow. In contrast, infections with VZV required damage to the HCEE and did not spread. Acyclovir dramatically reduced replication of HSV-1 in this model. We conclude that highly quality-controlled, readily available HCEE is a useful model to study human-restricted herpesvirus infection of the human corneal epithelium and for screening of antiviral drugs for treating HSK in an 3D model system.

Background and Objectives: Herpes simplex keratitis (HSK) is the leading infectious cause of corneal damage and associated loss of visual acuity. Because of its frequent recurrence, it represents a major health problem; thus, timely and accurate diagnosis is the key to successful treatment. To enable this, we aimed to determine HSK patients\' demographic and clinical features. Materials and Methods: This prospective study included 55 patients diagnosed with HSK between March 2019 and August 2022 at the Department of Ophthalmology, Clinical Hospital Rijeka. Results: We found that HSK is most prevalent in the elderly, with 72.73% of patients older than 60. The most common HSK types were dendritic (HSK-D; 43.64%) and stromal with epithelial ulceration (HSK-SEU 23.64%). HSK recurrences occurred in 65.45% of patients, with most having two to five recurrences (55.56%). Visual acuity at presentation (65.5%) and after treatment (50.9%) was mostly in the 20/50 range. The longest period until the disease symptoms were resolved was in the group with stromal HSK without epithelial ulceration (HSK-SnEU), for which symptoms lasted more than 11 weeks in 87.5% of patients. The overall incidence of HSK-related complications was high (85.45%), with 76.4% of patients having corneal scarring. The average time from symptom to treatment was 15.78 days. Interestingly, we observed a strong seasonality in the incidence of HSK, which was most prevalent in the colder months, with 63.6% of cases occurring between October and March. Conclusions: To the best of our knowledge, this is the first prospective study in Croatia, and one of the few in Europe, to describe the demographic and clinical features of HSK patients. We found that HSK is most common in the elderly population, with its dendritic form as a clinical presentation. We have shown that HSK is prone to recurrence and secondary complications, with a worryingly long time between symptom and treatment, indicating the need for diagnostic testing in routine practice.

UNASSIGNED: Herpes simplex keratitis stands as a prominent factor contributing to infectious blindness among developed nations. On a global scale, over 60% of the population tests positive for herpes simplex virus type-1 (HSV-1). Despite these statistics, there is currently no vaccine available for the virus. Moreover, the conventional nucleoside drugs prescribed to patients are proving ineffective in addressing issues related to drug resistance, recurrence, latency, and the escalating risk of vision loss. Hence, it is imperative to continually explore all potential avenues to restrict the virus. This review article centers on the present treatment methods for HSV-1 keratitis (HSK), highlighting the ongoing clinical trials. It delves into the emerging drugs, their mode-of-action and future therapeutics.
UNASSIGNED: The review focuses on the significance of a variety of small molecules targeting HSV-1 lifecycle at multiple steps. Peer-reviewed articles and abstracts were searched in MEDLINE, PubMed, Embase, and clinical trial websites.
UNASSIGNED: The exploration of small molecules that target specific pathways within the herpes lifecycle holds the potential for substantial impact on the antiviral pharmaceutical market. Simultaneously, the pursuit of disease-specific biomarkers has the capacity to usher in a transformative era in diagnostics within the field.