Ocular A-to-I RNA editing signatures associated with SARS-CoV-2 infection.

Ophthalmic manifestations have recently been observed in acute and post-acute complications of COVID-19 caused by SARS-CoV-2 infection. Our precious study has shown that host RNA editing is linked to RNA viral infection, yet ocular adenosine to inosine (A-to-I) RNA editing during SARS-CoV-2 infection remains uninvestigated in COVID-19. Herein we used an epitranscriptomic pipeline to analyze 37 samples and investigate A-to-I editing associated with SARS-CoV-2 infection, in five ocular tissue types including the conjunctiva, limbus, cornea, sclera, and retinal organoids. Our results revealed dramatically altered A-to-I RNA editing across the five ocular tissues. Notably, the transcriptome-wide average level of RNA editing was increased in the cornea but generally decreased in the other four ocular tissues. Functional enrichment analysis showed that differential RNA editing (DRE) was mainly in genes related to ubiquitin-dependent protein catabolic process, transcriptional regulation, and RNA splicing. In addition to tissue-specific RNA editing found in each tissue, common RNA editing was observed across different tissues, especially in the innate antiviral immune gene MAVS and the E3 ubiquitin-protein ligase MDM2. Analysis in retinal organoids further revealed highly dynamic RNA editing alterations over time during SARS-CoV-2 infection. Our study thus suggested the potential role played by RNA editing in ophthalmic manifestations of COVID-19, and highlighted its potential transcriptome impact, especially on innate immunity.

Fatal Infection in Ferrets after Ocular Inoculation with Highly Pathogenic Avian Influenza A(H5N1) Virus.

Ocular inoculation of a clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) virus caused severe and fatal infection in ferrets. Virus was transmitted to ferrets in direct contact. The results highlight the potential capacity of these viruses to cause human disease after either respiratory or ocular exposure.

Dose-Dependent Response to Infection with Ebola Virus in the Ferret Model and Evidence of Viral Evolution in the Eye.

Filoviruses cause high-consequence infections with limited approved medical countermeasures (MCMs). MCM development is dependent upon well-characterized animal models for the assessment of antiviral agents and vaccines. Following large-scale Ebola virus (EBOV) disease outbreaks in Africa, some survivors are left with long-term sequelae and persistent virus in immune-privileged sites for many years. We report the characterization of the ferret as a model for Ebola virus infection, reproducing disease and lethality observed in humans. The onset of clinical signs is rapid, and EBOV is detected in the blood, oral, and rectal swabs and all tissues studied. We identify viral RNA in the eye (a site of immune privilege) and report on specific genomic changes in EBOV present in this structure. Thus, the ferret model has utility in testing MCMs that prevent or treat long-term EBOV persistence in immune-privileged sites. IMPORTANCE Recent reemergence of Ebola in Guinea that caused over 28,000 cases between 2013 and 2016 has been linked to the original virus from that region. It appears the virus has remained in the region for at least 5 years and is likely to have been maintained in humans. Persistence of Ebola in areas of the body for extended periods of time has been observed, such as in the eye and semen. Despite the importance of reintroduction of Ebola from this route, such events are rare in the population, which makes studying medical interventions to clear persistent virus difficult. We studied various doses of Ebola in ferrets and detected virus in the eyes of most ferrets. We believe this model will enable the study of medical interventions that promote clearance of Ebola virus from sites that promote persistence.

Transcriptional analysis of immune response genes during pathogenesis of cytomegalovirus retinitis in mice with murine acquired immunodeficiency syndrome.

Human cytomegalovirus (HCMV) is an opportunistic human herpesvirus that causes a sight-threatening retinitis in immunosuppressed patients, especially those with AIDS. Using an established model of experimental murine cytomegalovirus (MCMV) retinitis in mice with retrovirus-induced immunodeficiency (MAIDS), we have been attempting to define with greater clarity the immunologic mechanisms that contribute to the progression of AIDS-related HCMV retinitis in the unique immunosuppressive setting of HIV infection. Toward this end, we provide herein a comprehensive assessment of immune response gene expression during the onset and development of MAIDS-related MCMV retinitis employing NanoString nCounter. In so doing, we analyzed and compared the intraocular expressions of 561 immune response genes within MCMV-infected eyes of groups of healthy mice, MCMV-infected mice with MAIDS of 4 weeks' (MAIDS-4) duration, and MCMV-infected eyes of mice with MAIDS of 10 weeks' (MAIDS-10) duration. These animal groups show a progression of retinal disease from absolute resistance to retinitis development in healthy mice to the development of classic full-thickness retinal necrosis in MAIDS-10 mice but through an intermediate stage of retinal disease development in MAIDS-4 mice. Our findings showed that increased susceptibility to MCMV retinitis during the progression of MAIDS is associated with robust upregulation or downregulation of a surprisingly large number of immune response genes that operate within several immune response pathways often unique to each animal group. Analysis of 14 additional immune response genes associated with programmed cell death pathways suggested involvement of necroptosis and pyroptosis during MAIDS-related MCMV retinitis pathogenesis. Use of the NanoString nCounter technology provided new and unexpected information on the immunopathogenesis of retinitis within MCMV-infected eyes of mice with retrovirus-induced immunosuppression. Our findings may provide new insights into the immunologic events that operate during the pathogenesis of AIDS-related HCMV retinitis.

Upregulation of Multiple CD8+ T Cell Exhaustion Pathways Is Associated with Recurrent Ocular Herpes Simplex Virus Type 1 Infection.

A large proportion of the world's population harbors latent HSV type 1 (HSV-1). Cross-talk between antiviral CD8+ T cells and HSV-1 appear to control latency/reactivation cycles. We found that compared with healthy asymptomatic individuals, in symptomatic (SYMP) patients, the CD8+ T cells with the same HLA-A*0201-restricted HSV-1 epitope specificities expressed multiple genes and proteins associated to major T cell exhaustion pathways and were dysfunctional. Blockade of immune checkpoints with anti-LAG-3 and anti-PD-1 antagonist mAbs synergistically restored the frequency and function of antiviral CD8+ T cells, both 1) ex vivo, in SYMP individuals and SYMP HLA-A*0201 transgenic mice; and 2) in vivo in HSV-1-infected SYMP HLA-A*0201 transgenic mice. This was associated with a significant reduction in virus reactivation and recurrent ocular herpetic disease. These findings confirm antiviral CD8+ T cell exhaustion during SYMP herpes infection and pave the way to targeting immune checkpoints to combat recurrent ocular herpes.

COVID-19 and the Human Eye: Conjunctivitis, a Lone COVID-19 Finding - A Case-Control Study.

OBJECTIVES: COVID-19 has varied clinical manifestations, from asymptomatic to severe cases, and conjunctivitis is one of them, but sometimes a lone initial symptom is found to be present. The aim of this study was to identify the prevalence of conjunctivitis as the first symptom in COVID-19 patients in a primary healthcare unit. METHODOLOGY: A retrospective study was conducted, analyzing the presenting complains/symptoms and results of COVID-19-confirmatory tests. RESULTS: Out of the 672 cases that were sent for RT-PCR testing, only 121 (18%) were found to be positive. Among these, 2.67% patients had both conjunctivitis and COVID-19, 77.77% patients had unilateral eye affected, while 22.22% had bilateral conjunctivitis of varying degrees. Fifteen patients diagnosed to have both acute conjunctivitis and COVID-19 presented other symptoms associated with COVID-19 infection. Three patients had only acute conjunctivitis during their entire course of COVID-19. CONCLUSIONS: Conjunctivitis is a symptom of COVID-19 and may be the first sign of the infection, until the onset of the classical manifestations; such patients may continue to be a viral reservoir. Physicians should not miss unilateral conjunctivitis as it can be the only presenting complaint of COVID-19 during the initial phase, which might worsen if undetected and can aid in the spread of the contagion.

An outbreak of adenovirus D8 keratoconjunctivitis in Leicester, United Kingdom, from March to August 2019.

We report a large epidemic (n = 126) of keratoconjunctivitis predominantly with two lineages of adenovirus (AdV) type D8 in patients seen in eye casualty between march and August 2019. Other AdV species identified by viral sequencing included B, C, and E. Despite various features of more severe eye disease being present, these were not significantly different between the different AdV species, with similar rates of pseudomembrane formation and keratitis observed in patients with AdV species B as for those with AdV species D.

Ocular findings in patients with coronavirus disease 2019 (COVID-19) in an outbreak hospital.

PURPOSE: The aim of this study was to investigate the ocular findings observed in patients with coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 and to present the relationship between ocular involvement, systemic findings, and laboratory results. MATERIAL AND METHODS: This cross-sectional study was carried out between 1 May and 30 June 2020. The study included 359 patients diagnosed with COVID-19 and assessed by clinical evaluation, nasopharyngeal polymerase chain reaction, and lung computed tomography. RESULTS: One hundred ninety-seven (54.9%) of the patients were male and 162 (45.1%) were female. The mean age of the patients was 58.5 years (20-91). Two hundred ninety-four (81.9%) patients were treated in the inpatient clinic and 65 (18.1%) patients were treated in the intensive care unit. Various ocular diseases were observed in 16 (4.5%) of the patients. Although the rate of ocular disease was 12 out of 294 (4.1%) in patients followed up in the inpatient clinic, this rate was 4 out of 65 (6.2%) in intensive care patients. There was no systemic problem in one patient, in whom conjunctival hyperemia was the first and only reason for admission to the hospital. Four patients followed up in the inpatient clinic had conjunctivitis at the time of admission, and conjunctivitis occurred in three patients during hospitalization. Subconjunctival hemorrhage occurred in five patients and vitreous hemorrhage in one patient. CONCLUSION: Ocular diseases are uncommon in COVID-19 patients but may occur during the first period of the disease or during follow-up. Ocular diseases may be the initial or only sign of COVID-19 infection.

Fluorescence of ocular surface in a Covid -19 patient after Favipiravir treatment: a case report.

BACKGROUND: Favipiravir is used in treatment of Covid-19 patients. We aimed to share of ocular surface fluorescence in a patient after Favipiravir treatment in this case report. CASE PRESENTATION: A 20-year-old male patient declared no known systemic disease prior to Covid-19. He applied to us with blurry vision and blue light reflection after Covid-19 treatment with Favipiravir. We observed bilateral fluorescence on his eyes and fluorescence of his nails. Biomicroscopic examination was insignificant. CONCLUSION: We investigated the fluorescence of favipiravir tablets under ultraviolet light. Drug demonstrated fluorescence. We recorded the favipiravir fluorescence in-vitro. This appears to be a strong evidence in terms of the linkage between the fluorescence of the ocular surface and favipiravir.

Value of anal swabs for SARS-COV-2 detection: a literature review.

Facing the unprecedented global public health crisis caused by coronavirus disease 2019 (COVID-19), nucleic acid tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are the gold standard for diagnosing COVID-19. The asymptomatic carriers were not suspected of playing a significant role in the ongoing pandemic, and universal nucleic acid screening in close contacts of confirmed cases and asymptomatic carriers has been carried out in many medium- and high-risk areas for the spread of the virus. Recently, anal swabs for key population screening have been shown to not only reduce missed diagnoses but also facilitate the traceability of infectious sources. As a specimen for the detection of viruses, the goal of this paper is to briefly review the transmission route of SARS-CoV-2 and the necessity of using anal swabs for SARS-CoV-2 screening to minimize transmission and a threat to other people with COVID-19.

Dengue virus infects the mouse eye following systemic or intracranial infection and induces inflammatory responses.

Dengue virus (DENV) infection is associated with clinical ocular presentations and here DENV infection of the eye was assessed in mice. In an AG129 mouse model of antibody-dependent enhancement of DENV infection, DENV RNA was detected in the eye and vascular changes were present in the retinae. Intraocular CD8 and IFN-γ mRNA were increased in mice born to DENV-naïve, but not DENV-immune mothers, while TNF-α mRNA was induced and significantly higher in mice born to DENV-immune than DENV-naïve mothers. DENV RNA was detected in the eye following intracranial DENV infection and CD8 mRNA but not IFN-γ nor TNF-α were induced. In all models, viperin was increased following DENV infection. Thus, DENV in the circulation or the brain can infect the eye and stimulate innate immune responses, with induction of viperin as one response that consistently occurs in multiple DENV eye-infection models in both an IFN-dependent and independent manner.

The Latency-Associated Transcript Inhibits Apoptosis via Downregulation of Components of the Type I Interferon Pathway during Latent Herpes Simplex Virus 1 Ocular Infection.

The herpes simplex virus (HSV-1) latency-associated transcript (LAT) has been shown to inhibit apoptosis via inhibiting activation of proapoptotic caspases. However, the mechanism of LAT control of apoptosis is unclear, because LAT is not known to encode a functional protein, and the LAT transcript is found largely in the nucleus. We hypothesized that LAT inhibits apoptosis by regulating expression of genes that control apoptosis. Consequently, we sought to establish the molecular mechanism of antiapoptosis functions of LAT at a transcriptional level during latent HSV-1 ocular infection in mice. Our results suggest the following. (i) LAT likely inhibits apoptosis via upregulation of several components of the type I interferon (IFN) pathway. (ii) LAT does not inhibit apoptosis via the caspase cascade at a transcriptional level or via downregulating Toll-like receptors (TLRs). (iii) The mechanism of LAT antiapoptotic effect is distinct from that of the baculovirus inhibitor of apoptosis (cpIAP) because replacement of LAT with the cpIAP gene resulted in a different gene expression pattern than in either LAT+ or LAT- viruses. (iv) Replacement of LAT with the cpIAP gene does not cause upregulation of CD8 or markers of T cell exhaustion despite their having similar levels of latency, further supporting that LAT and cpIAP function via distinct mechanisms.IMPORTANCE The HSV-1 latency reactivation cycle is the cause of significant human pathology. The HSV-1 latency-associated transcript (LAT) functions by regulating latency and reactivation, in part by inhibiting apoptosis. However, the mechanism of this process is unknown. Here we show that LAT likely controls apoptosis via downregulation of several components in the JAK-STAT pathway. Furthermore, we provide evidence that immune exhaustion is not caused by the antiapoptotic activity of the LAT.

Cytomegalovirus establishes a latent reservoir and triggers long-lasting inflammation in the eye.

Recent outbreaks of Ebola and Zika have highlighted the possibility that viruses may cause enduring infections in tissues like the eye, including the neural retina, which have been considered immune privileged. Whether this is a peculiarity of exotic viruses remains unclear, since the impact of more common viral infections on neural compartments has not been examined, especially in immunocompetent hosts. Cytomegalovirus is a common, universally distributed pathogen, generally innocuous in healthy individuals. Whether in immunocompetent hosts cytomegalovirus can access the eye, and reside there indefinitely, was unknown. Using the well-established murine cytomegalovirus infection model, we show that systemic infection of immunocompetent hosts results in broad ocular infection, chronic inflammation and establishment of a latent viral pool in the eye. Infection leads to infiltration and accumulation of anti-viral CD8+ T cells in the eye, and to the development of tissue resident memory T cells that localize to the eye, including the retina. These findings identify the eye as an unexpected reservoir for cytomegalovirus, and suggest that common viruses may target this organ more frequently than appreciated. Notably, they also highlight that infection triggers sustained inflammatory responses in the eye, including the neural retina.

Typical gene expression profile of pseudorabies virus reactivation from latency in swine trigeminal ganglion.

Pseudorabies virus (PRV) establishes a lifelong latent infection in swine trigeminal ganglion (TG) following acute infection. Increased corticosteroid levels, due to stress, increases the incidence of reactivation from latency. Muscle injection combined with intravenous deliver of the synthetic corticosteroid dexamethasone (DEX) consistently induces reactivation from latency in pigs. In this study, PRV-free piglets were infected with PRV. Viral shedding in nasal and ocular swabs demonstrated that PRV infection entered the latent period. The anti-PRV antibody was detected by enzyme-linked immunosorbent assay and the serum neutralization test, which suggested that the PRV could establish latent infection in the presence of humoral immunity. Immunohistochemistry and viral genome detection of TG neurons suggested that PRV was reactivated from latency. Viral gene expressions of IE180, EP0, VP16, and LLT-intron were readily detected at 3-h post-DEX treatment, but gB, a γ1 gene, was not detectable. The differentially expressed phosphorylated proteins of TG neurons were analyzed by ITRAQ coupled with LC-MS/MS, and p-EIF2S2 differentially expression was confirmed by western blot assay. Taken together, our study provides the evidence that typical gene expression in PRV reactivation from latency in TG is disordered compared with known lytic infection in epithelial cells.

Arboviruses (chikungunya, dengue, and Zika) associated with ophthalmic changes: a focus on aqueous fluid and vitreous humor.

The aim of this study was to conduct a bibliographic survey and correlates the presence of arboviroses in the eyeball with the main eye changes presented by the population under study. This study is a systematic review of journals and indexed articles, carried out between January 2019 and June 2019, in which there was a query in the Pubmed/Medline and Scielo databases without temporal restriction. In addition to the aforementioned databases, the Brazilian Association of Organ Transplantation Association database, which provides epidemiological data on organ and tissue transplants in Brazil, was used as a research source. The Midwest region contributed to the increase in the number of organ transplants in Brazil. The number of corneal transplants in Brazil surpassed the number of organ transplants by four times. Several ophthalmic changes associated with Chikungunya, Dengue, and Zika virus infections have been diagnosed; however, few studies have identified the presence of the virus in the eyeball. Arboviruses are of great relevance to public health due to a number of factors, ranging from the diversity of infectious agents involved and the plurality of clinical manifestations because the absence of efficient laboratory support, leading to delayed disease confirmation due to lack of differential diagnostics available. Added to these difficulties is the lack of specific therapy, leaving only the symptomatic control of clinical manifestations as the only treatment option. However, the manifestations are directly associated with the decreased quality of vision and consequently the quality of life of patients.

Ocular and Lacrimal Gland Lesions in Naturally Occurring Rabies of Domestic and Wild Mammals.

Investigations describing the ocular and lacrimal gland lesions associated with rabies are sparse. Here we characterize the pathological changes and distribution of rabies viral antigen in the eye, optic nerve, and lacrimal gland of 18 rabies cases from different mammalian species. Histology and immunohistochemistry for rabies virus, CD3, CD20, and Iba1 were performed on tissue sections of eye, optic nerve, and lacrimal gland. Polymerase chain reaction (PCR) for rabies was performed on all cases, including 7 formalin-fixed, paraffin-embedded (FFPE) and 11 frozen tissue samples of eye and lacrimal gland. Pathological changes in the eye consisted of retinal necrosis (12/18 cases) with occasional viral inclusions within ganglion cells (8/12 cases). Immunohistochemically, viral antigen was detected within the nerve fiber layer, ganglion cells, and inner plexiform layer in all 12 cases with retinal lesions and in 2 cases with no retinal lesions, as well as optic nerve (6/18 cases) and lacrimal gland epithelium (3/18 cases). CD3+ T lymphocytes were present in the retina (11/18 cases), optic nerve (2/18 cases), and lacrimal gland (11/18 cases). No CD20+ B lymphocytes or Iba1+ macrophages were detected. PCR for rabies virus was positive in 9 of 11 frozen samples but in only 2 of 7 FFPE samples. Five samples that were negative for rabies by PCR were positive by immunohistochemistry, and 2 samples were negative by both tests. These results provide evidence that rabies virus infection extends to the eye, likely via the ocular nerve, and that the lacrimal gland might be a source of viral infection.

Investigation of routes of entry and dispersal pattern of RGNNV in tissues of European sea bass, Dicentrarchus labrax.

Viral encephalopathy and retinopathy (VER) is a serious neuropathological fish disease affecting in the Mediterranean aquaculture mainly European sea bass, Dicentrarchus labrax. It is well known that betanodaviruses are neurotropic viruses that replicate in nerve tissues, preferentially brain and retina. However, routes of entry and progression of the virus in the central nervous system (CNS) remain unclear. The role of four tissues-eye, oesophagus, gills and skin-as possible gateways of a betanodavirus, the redspotted grouper nervous necrosis virus (RGNNV), was investigated after experimental challenges performed on European seabass juveniles. The dispersal pattern of Betanodavirus at primarily stages of the disease was also assessed, using a real-time qPCR assay. The development of typical clinical signs of VER, the presence of characteristic histopathological lesions in the brain and retina and the detection of viral RNA in the tissues of all experimental groups ascertained that successful invasion of RGNNV under all experimental routes was achieved. Transneuronal spread along pathways known to be connected to the initial site of entry seems to be the predominant scenario of viral progression in the CNS. Furthermore, viraemia appeared only after the installation of the infection in the brain.

[A special on epidemic prevention and control: precautions in ophthalmic practice in the prevention and control of the novel coronavirus pneumonia epidemic].

This article was published ahead of print on the official website of Chinese Journal of Ophthalmology on March 2, 2020. Prevention and control of novel coronavirus pneumonia is now the top priority, and the protection of the eyes in the fight against the epidemic has also been an issue of great concern. Based on the latest progress made in basic and clinical research and practical experience in epidemic prevention and control, this article delivers objective guidance on whether the eye is a route of transmission of novel coronavirus infection, the precautions that should be taken by ophthalmologists in clinical practice during the epidemic, the novel coronavirus infection in the eyes and its clinical manifestation, and the public health education on eye protection, so as to provide valuable evidence for the scientific prevention and control of the epidemic and developing targeted countermeasures. (Chin J Ophthalmol, 2020, 56: 330-332).

Roles of the Phosphorylation of Herpes Simplex Virus 1 UL51 at a Specific Site in Viral Replication and Pathogenicity.

Herpes simplex virus 1 (HSV-1) UL51 is a phosphoprotein that functions in the final envelopment in the cytoplasm and viral cell-cell spread, leading to efficient viral replication in cell cultures. To clarify the mechanism by which UL51 is regulated in HSV-1-infected cells, we focused on the phosphorylation of UL51. Mass spectrometry analysis of purified UL51 identified five phosphorylation sites in UL51. Alanine replacement of one of the identified phosphorylation sites in UL51, serine 184 (Ser-184), but not the other identified phosphorylation sites, significantly reduced viral replication and cell-cell spread in HaCaT cells. This mutation induced membranous invaginations adjacent to the nuclear membrane, the accumulation of primary enveloped virions in the invaginations and perinuclear space, and mislocalized UL34 and UL31 in punctate structures at the nuclear membrane; however, it had no effect on final envelopment in the cytoplasm of HaCaT cells. Of note, the alanine mutation in UL51 Ser-184 significantly reduced the mortality of mice following ocular infection. Phosphomimetic mutation in UL51 Ser-184 partly restored the wild-type phenotype in cell cultures and in mice. Based on these results, we concluded that some UL51 functions are specifically regulated by phosphorylation at Ser-184 and that this regulation is critical for HSV-1 replication in cell cultures and pathogenicity in vivoIMPORTANCE HSV-1 UL51 is conserved in all members of the Herpesviridae family. This viral protein is phosphorylated and functions in viral cell-cell spread and cytoplasmic virion maturation in HSV-1-infected cells. Although the downstream effects of HSV-1 UL51 have been clarified, there is a lack of information on how this viral protein is regulated as well as the significance of the phosphorylation of this protein in HSV-1-infected cells. In this study, we show that the phosphorylation of UL51 at Ser-184 promotes viral replication, cell-cell spread, and nuclear egress in cell cultures and viral pathogenicity in mice. This is the first report to identify the mechanism by which UL51 is regulated as well as the significance of UL51 phosphorylation in HSV-1 infection. Our study may provide insights into the regulatory mechanisms of other herpesviral UL51 homologs.

An M2 Rather than a TH2 Response Contributes to Better Protection against Latency Reactivation following Ocular Infection of Naive Mice with a Recombinant Herpes Simplex Virus 1 Expressing Murine Interleukin-4.

We found previously that altering macrophage polarization toward M2 responses by injection of colony-stimulating factor 1 (CSF-1) was more effective in reducing both primary and latent infections in mice ocularly infected with herpes simplex virus 1 (HSV-1) than M1 polarization by gamma interferon (IFN-γ) injection. Cytokines can coordinately regulate macrophage and T helper (TH) responses, with interleukin-4 (IL-4) inducing type 2 TH (TH2) as well as M2 responses and IFN-γ inducing TH1 as well as M1 responses. We have now differentiated the contributions of these immune compartments to protection against latency reactivation and corneal scarring by comparing the effects of infection with recombinant HSV-1 in which the latency-associated transcript (LAT) gene was replaced with either the IL-4 (HSV-IL-4) or IFN-γ (HSV-IFN-γ) gene using infection with the parental (LAT-negative) virus as a control. Analysis of peritoneal macrophages in vitro established that the replacement of LAT with the IL-4 or IFN-γ gene did not affect virus infectivity and promoted polarization appropriately. Protection against corneal scarring was significantly higher in mice ocularly infected with HSV-IL-4 than in those infected with HSV-IFN-γ or parental virus. Levels of primary virus replication in the eyes and trigeminal ganglia (TG) were similar in the three groups of mice, but the numbers of gC+ cells were lower on day 5 postinfection in the eyes of HSV-IL-4-infected mice than in those infected with HSV-IFN-γ or parental virus. Latency and explant reactivation were lower in both HSV-IL-4- and HSV-IFN-γ-infected mice than in those infected with parental virus, with the lowest level of latency being associated with HSV-IL-4 infection. Higher latency correlated with higher levels of CD8, PD-1, and IFN-γ mRNA, while reduced latency and T-cell exhaustion correlated with lower gC+ expression in the TG. Depletion of macrophages increased the levels of latency in all ocularly infected mice compared with their undepleted counterparts, with macrophage depletion increasing latency in the HSV-IL-4 group greater than 3,000-fold. Our results suggest that shifting the innate macrophage immune responses toward M2, rather than M1, responses in HSV-1 infection would improve protection against establishment of latency, reactivation, and eye disease.IMPORTANCE Ocular HSV-1 infections are among the most frequent serious viral eye infections in the United States and a major cause of virus-induced blindness. As establishment of a latent infection in the trigeminal ganglia results in recurrent infection and is associated with corneal scarring, prevention of latency reactivation is a major therapeutic goal. It is well established that absence of latency-associated transcripts (LATs) reduces latency reactivation. Here we demonstrate that recombinant HSV-1 expressing IL-4 (an inducer of TH2/M2 responses) or IFN-γ (an inducer of TH1/M1 responses) in place of LAT further reduced latency, with HSV-IL-4 showing the highest overall protective efficacy. In naive mice, this higher protective efficacy was mediated by innate rather than adaptive immune responses. Although both M1 and M2 macrophage responses were protective, shifting macrophages toward an M2 response through expression of IL-4 was more effective in curtailing ocular HSV-1 latency reactivation.