Herpesvirus Infection Research Articles

Control of HSV-1 Infection: Directions for the Development of CRISPR/Cas-Based Therapeutics and Diagnostics

It is estimated that nearly all individuals have been infected with herpesviruses, with herpes simplex virus type 1 (HSV-1) representing the most prevalent virus. In most cases, HSV-1 causes non-life-threatening skin damage in adults. However, in patients with compromised immune systems, it can cause serious diseases, including death. The situation is further complicated by the emergence of strains that are resistant to both traditional and novel antiviral drugs. It is, therefore, imperative that new methods of combating HSV-1 and other herpesviruses be developed without delay. CRISPR/Cas systems may prove an effective means of controlling herpesvirus infections. This review presents the current understanding of the underlying molecular mechanisms of HSV-1 infection and discusses four potential applications of CRISPR/Cas systems in the fight against HSV-1 infections. These include the search for viral and cellular genes that may serve as effective targets, the optimization of anti-HSV-1 activity of CRISPR/Cas systems in vivo, the development of CRISPR/Cas-based HSV-1 diagnostics, and the validation of HSV-1 drug resistance mutations.

A case of congenital cytomegalovirus infection in a child with Prader–Willi syndrome

A possible manifestation of intrauterine infection with herpes viruses can be severe eye damage. Various visual disturbances with negative consequences have been described in Prader–Willi syndrome. The article describes bilateral chorioretinitis in a child with Prader–Willi syndrome, which developed against the background of congenital herpetic infection of CMV etiology.

The evaluation of the effectiveness of bacterial lysate in preoperative preparation of children with adenotonsillar pathology

In childhood, the occurrence and steady growth of diseases of the nasopharyngeal tonsils, often acquiring a chronic course and occurring with exacerbations and complications, is facilitated by a number of factors. Etiological factors of adenotonsillar diseases in children are both bacterial and viral pathogens, among which respiratory viruses are among the most significant. Herpes virus infections (HVI) play an important role in the development of chronic upper respiratory tract pathology, especially in the cohort of frequently ill children. Representatives of the herpes virus family are characterized by lymphotropic action, long-term persistence in the body, and a tendency to reproduce in cells, leading to a violation of the immune status. The incidence of relapses in the postoperative period during surgical interventions in the ENT organs in children remains high. Herpesvirus etiology of recurrent infectious and inflammatory diseases of the URT (upper respiratory tract) is the leading factor in the ineffectiveness of tonsillotomy, adenotomy, and repeated proliferation of lymphoid tissue in the postoperative period in preschool children. The use of a drug from the group of bacterial lysates before surgery is justified in the treatment of frequently and long-term ill children with adenotonsillar hypertrophy.

Unlocking insights: Mahout's perceptions and practices in managing Elephant Endotheliotropic Herpesvirus (EEHV) infection among captive Asian elephants in Surin province, Thailand.

Surin, situated in the northeastern region of Thailand, has earned the reputation of being an "elephant village" due to its high captive elephant population and unique tradition of elephant rearing. However, the continuous occurrence of elephant endotheliotropic herpesvirus (EEHV) infection poses a significant threat to elephants, particularly the young ones. This study investigated various aspects of EEHV-related elephant care among ninety-two mahouts at the Surin Elephant Kingdom Project. This study used semi-structured interviews and observations to assess the mahouts' knowledge, attitude, and practice (KAP scores) toward EEHV transmission, prevention, and management. The result revealed knowledge and practice scores below expectations, indicating an insufficient understanding the nature of disease and preventive measures. However, the mahouts exhibited awareness of the severity of the disease and factors contributing to transmission risk. Regarding the relationship among KAP scores, a positive correlation was observed at a low level (p < 0.05) between the knowledge and practice scores. Interestingly, approximately 55% of the survey respondents were confident that their elephants would not receive EEHV, leading to inadequate prevention measures. From the result, it is crucial to provide comprehensive knowledge about the nature of the disease and preventive measures to all mahouts. This education should emphasize the importance of early monitoring signs, appropriate weaning age, and preventing viral transmission practices. The KAP survey offers valuable insights that can identify areas requiring improvement and guide the development of effective and targeted disease prevention programs within the specific population. Therefore, it is recommended that the KAP survey should be employed in other parts of the country where the elephant management system differs.

Inflammatory Bowel Disease in Activated PI3Kδ Syndrome: An Uncommon Complication of a Rare Condition

Background/Objectives: Monogenic primary immunodeficiencies represent a group of disorders with varying levels of severity, many of which remain poorly understood. Activated phosphoinositide-3 kinase delta syndrome (APDS) is a rare genetic condition resulting from dominant point mutations in the phosphoinositide-3 kinase delta (PI3Kδ) gene, which leads to hyperactivation of the PI3Kδ enzyme, primarily expressed in T and B lymphocytes. Children with this mutation often have recurrent sinopulmonary infections and immunodeficiency. Additional complications may include increased susceptibility to herpes virus infections, lymphoid hyperplasia, and autoimmune conditions. In this case, report, we describe the clinical course of a young boy diagnosed with APDS who developed unclassified inflammatory bowel disease (U-IBD) and explore a personalized treatment approach. Methods: We detail the clinical course of a 12-year-old boy with APDS who presented with fever, diarrhea, anemia, and significant weight loss. Diagnostic evaluations, including endoscopy and histological analysis, led to a diagnosis of U-IBD. Genetic testing confirmed a heterozygous PIK3CD mutation (c.G3061A, p.E1021K). Results: Although APDS is characterized by a broad spectrum of immune dysregulation, the occurrence of IBD in this context is rare. We managed the patient’s IBD with exclusively enteral nutrition to induce remission, followed by a maintenance regimen combining the Crohn’s Disease Exclusion Diet (CDED) and mesalamine, achieving sustained long-term clinical remission. Conclusions: This case underscores the importance of personalized treatment approaches in managing the complex manifestations of APDS.

Low Infection Rates With Long-Term Dupilumab Treatment in Patients Aged 6 Months to 5 Years: An Open-Label Extension Study.

To evaluate long-term infection rates in children aged 6 months to 5 years with moderate-to-severe atopic dermatitis (AD) treated with dupilumab. This was a post hoc analysis of an ongoing open-label extension (OLE) study of dupilumab. Pediatric patients aged 6 months to 5 years with moderate-to-severe AD who had previously taken part in the LIBERTY AD PRESCHOOL phase 2 and 3 clinical trials received weight-based subcutaneous dupilumab every 2 or 4 weeks. Exposure-adjusted infection rates after a median dupilumab exposure of 52 weeks are compared with data from the earlier randomized, placebo-controlled, 16-week LIBERTY AD PRESCHOOL phase 3 trial. Infection rates were overall lower in the OLE study compared with the dupilumab and placebo groups in the earlier 16-week trial, including total infections (101.0 patients/100 patient-years [PY]), nonherpetic skin infections (22.7 patients/100PY), herpetic infections (7.3 patients/100PY), and nonskin infections (92.9 patients/100PY). The frequency of severe and serious infections was low (3.1 patients/100PY), compared with 17.1 placebo-treated patients/100PY and 0 dupilumab-treated patients in the earlier 16-week trial, and no infections leading to treatment discontinuation were observed. Systemic anti-infective medication use (58.9 patients/100PY) was lower in the OLE study compared with both the dupilumab and placebo groups in the 16-week trial. Overall, reduced infection rates are observed in infants and young children with moderate-to-severe AD treated with dupilumab long-term, supporting the known safety profile of dupilumab.

Combined effect of basic antiherpetic drugs with a new inhibitor of the terminase complex of herpes simplex virus type 1 in Vero cell culture

More than 90% of the world’s population are carriers of herpes simplex virus type 1 (HSV-1). The infection manifests itself in the formation of blisters and ulcers on the face or genitals, and can cause blindness, encephalitis, and generalized infection. All modern first- and second-line antiherpetic drugs selectively inhibit viral DNA-polymerase. The purine-benzoxazine conjugate LAS-131 [(S)-4-[6-(purin-6-yl)aminohexanoyl]-7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine], which we described earlier, uses the large subunit of the HSV-1 terminase complex as a biotarget and selectively inhibits its reproduction in vitro. For the first time, we have obtained fundamentally new results on the combined effect of LAS-131 on human herpesvirus infection with practically significant antiviral compounds – nucleoside analogues (acyclovir [ACV], penciclovir [PCV], ganciclovir [GCV], brivudine [BVDU], iododeoxyuridine [IDU], adenine arabinoside [Ara-A], as well as a nucleoside phosphonate analogue (cidofovir [CDV]) and a pirophosphate analogue (foscarnet [FOS]). Using a inhibition assay of cytopathic effect (CPE) induced by a virus, it was shown that when combined with LAS-131, the concentrations of the compounds in combinations providing inhibition of HSV-1-induced CPE by 50%, decreased by 2 times (additive effect, FOS) or more (synergistic effect, ACV, PCV, GCV, IDU, BVDU, Ara-A, CDV). Reducing the concentrations of agents creates non-permissive conditions for the reproduction of HSV-1 and opens up new real possibilities for controlling human herpesvirus infection.

Valacyclovir versus valganciclovir for cytomegalovirus prophylaxis in kidney transplant recipients: a systematic review and comparative meta-analysis.

Valganciclovir (ValG) is the most widely used drug for cytomegalovirus (CMV) prophylaxis in kidney transplant recipients (KTRs). However, it is associated with dose-limiting side effects and considerable costs. Some centers have identified valacyclovir (ValA) as an economically attractive alternative with a lower risk of bone marrow suppression. The comparative effectiveness of these two drugs is not well-established. This study aims to compare the efficacy and safety of ValA and ValG for CMV prophylaxis in KTRs. Searches were conducted of the Medline, Cochrane, Web of Science, Embase, and Ovid databases. Endpoints encompassed the incidence of CMV disease, CMV viremia, acute rejection, leukopenia/neutropenia, and other infections, including BK polyomavirus and non-CMV herpesviruses (HVs). Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. Six studies, comprising 888 patients (438 receiving ValA), were included. The groups were comparable in CMV viremia incidence (RR, 0.70; 95% CI, 0.31-1.57; P=0.4) and the development of CMV disease (RR, 0.74; 95% CI, 0.09-5.97; P=0.8). No significant differences in acute rejection rates were observed (RR, 0.97; 95% CI, 0.50-1.91; P=0.8). However, the rate of leukopenia/neutropenia was significantly lower in the ValA group (RR, 0.57; 95% CI, 0.42-0.77; P<0.01). No significant differences were noted for BK viremia (RR, 0.67; 95% CI, 0.24-1.87; P=0.4) or other HV infections (RR, 1.43; 95% CI, 0.61-3.38; P=0.4). The drugs demonstrate comparable efficacy in preventing CMV infection following kidney transplantation. However, ValA may have a lower impact on bone marrow suppression.

Dupilumab for Chronic Hand Eczema: A Systematic Review and Meta-Analysis.

Chronic hand eczema (CHE) is a distressing and pervasive dermatologic condition, and effective treatment can be challenging. The novel IL-4/13 inhibitor dupilumab has shown clinical efficacy for atopic dermatitis (AD) and is being studied for CHE. PubMed database was searched for terms dupilumab and chronic hand eczema/dermatitis, including CHE subtypes (dyshidrotic, hyperkeratotic, allergic, contact, atopic, occupational, vesicular). Twenty-two study publications met inclusion and exclusion criteria for evaluation. Two multicenter prospective studies, one randomized controlled trial, two prospective observational studies, one retrospective study, nine case series, and seven case reports were included in the analysis with 374 total patients. Any partial response or complete resolution of CHE occurred in 80.3% of patients treated with dupilumab within 4-16 weeks of treatment. The patient response tended to increase throughout the duration of these studies for a significant percentage of patients, and for many it lasted beyond the study duration. Significant improvement in hand eczema severity scores and quality-of-life scores were noted. Efficacy was reported in over half of the cases of hyperkeratotic hand eczema; however, efficacy was decreased compared with relatively high consistent efficacy in other CHE subtypes such as dyshidrotic, vesicular, atopic, and contact CHE. Patients with current or previous AD had increased improvement scores compared to those without. The most common adverse effects were conjunctivitis (9.9%), herpes viral infection (1.4%), and facial erythema/dermatitis (1.3%). Dupilumab shows therapeutic efficacy in treating CHE. Further randomized controlled studies of dupilumab use in CHE subtypes are needed.

TRIM Proteins: Key Regulators of Immunity to Herpesvirus Infection

Herpesviruses are ubiquitous DNA viruses that can establish latency and cause a range of mild to life-threatening diseases in humans. Upon infection, herpesviruses trigger the activation of several host antiviral defense programs that play critical roles in curbing virus replication and dissemination. Recent work from many groups has integrated our understanding of TRIM (tripartite motif) proteins, a specific group of E3 ligase enzymes, as pivotal orchestrators of mammalian antiviral immunity. In this review, we summarize recent advances in the modulation of innate immune signaling by TRIM proteins during herpesvirus infection, with a focus on the detection of herpes simplex virus type 1 (HSV-1, a prototype herpesvirus) by cGAS-STING, RIG-I-like receptors, and Toll-like receptors. We also review the latest progress in understanding the intricate relationship between herpesvirus replication and TRIM protein-regulated autophagy and apoptosis. Finally, we discuss the maneuvers used by HSV-1 and other herpesviruses to overcome TRIM protein-mediated virus restriction.

FoxK1 and FoxK2 cooperate with ORF45 to promote late lytic replication of Kaposi's sarcoma-associated herpesvirus.

Lytic replication is essential for persistent infection of Kaposi's sarcoma-associated herpesvirus (KSHV) and the pathogenesis of related diseases, and many cellular pathways are hijacked by KSHV proteins to initiate and control the lytic replication of this virus. However, the mechanism involved in KSHV lytic replication from the early to the late phases remains largely undetermined. We previously revealed that KSHV open reading frame 45 (ORF45) plays important roles in late transcription and translation. In the present study, we revealed that the Forkhead box proteins FoxK1 and FoxK2 are ORF45-binding proteins and are essential for KSHV lytic gene expression and virion production, and that depletion of FoxK1 or FoxK2 significantly suppresses the expression of many late viral genes. FoxK1 and FoxK2 directly bind to the promoters of several late viral genes, ORF45 augments the promoter binding and transcriptional activity of FoxK1 and FoxK2, and then FoxK1 or FoxK2 cooperates with ORF45 to promote late viral gene expression. Our findings suggest that ORF45 interacts with FoxK1 and FoxK2 and promotes their occupancy on a cluster of late viral promoters and their subsequent transcriptional activity; consequently, FoxK1 and FoxK2 promote late viral gene expression to facilitate KSHV lytic replication.IMPORTANCEThe forkhead box proteins FoxK1 and FoxK2 can act as transcriptional inhibitors or activators to regulate several important processes, including aerobic glycolysis, metabolism, autophagy, and antiviral responses. However, the subversion and functions of FoxK1 and FoxK2 during KSHV infection and the pathogenesis of related diseases remain unknown. Here, we revealed that ORF45 binds to FoxK1 and FoxK2 and increases their transcriptional activity during KSHV lytic replication; consequently, FoxK1 and FoxK2 bind to late viral promoters and cooperate with ORF45 to promote late lytic gene expression. Our findings reveal two new ORF45 partners and a new function of ORF45 in which it utilizes FoxK1 and FoxK2 to promote transcription during late KSHV lytic replication.

Impact of bovine herpesvirus-1 infection on fertility in dairy cattle

Bovine herpesvirus-1 (BoHV-1) is endemic in the UK dairy herd and can have an important negative impact on fertility. As well as being the cause of infectious pustular vulvovaginitis and infectious balanoposthitis, BoHV-1 can reduce conception rate following introduction of the virus in contaminated semen at the time of artificial insemination. Its ability to cause abortions, particularly in the last trimester, is well-documented and the incidence of abortions can be high following the introduction of infection to naïve herds. The impact of BoHV-1 on herd fertility will depend on the degree of herd immunity, route of infection and strain of BoHV-1. Vaccination has been shown to reduce spread of BoHV-1 within and between herds, and to significantly reduce the risk of abortion. In light of the cost of a single abortion, and the impact of BoHV-1 on milk yield, routine vaccination against BoHV-1 offers a cost-effective control strategy suitable for most UK dairy herds.

Timeline and outcomes of viral and fungal infections after Chimeric Antigen Receptor (CAR) T-cell therapy: A large database analysis

ObjectivesThis large database analysis aims to describe the incidence, timeline, and risk factors for viral and fungal infections after chimeric antigen receptor (CAR) T-cell therapy. MethodsWe queried a global research network database, TriNetX, for patients who received CAR T-cell therapy, who were identified and followed for the development of viral and fungal infections. Baseline demographic, oncologic history, laboratory data and medication histories were collected. We evaluated risk factors for respiratory viral infections (RVI), herpesvirus, fungal infections and mortality using Cox regression. ResultsA total of 2,256 patients who received CAR T-cell therapy were included, 1,867 (82.7%) were CD19-targeted and 400 (17.7%) were BCMA-targeted. Following CAR T-cell infusion, RVI were the most prevalent (23.3%) with a median onset of 160 days (IQR 52-348 days), while herpesvirus and fungal infections were less frequent, occurring in 13.6% and 11.4% of cases with median onsets of 71 (IQR 18-252) and 73 days (IQR 14-236 days), respectively. On multivariable Cox regression, independent predictors of RVI included acute lymphoblastic leukemia (ALL, HR 1.61), prior hematopoietic cell transplant (HCT, HR 1.29), cytokine release syndrome (CRS, HR 1.41), hemophagocytic lymphohistiocytosis (HLH, HR 1.96), and glucocorticoids (HR 3.37). Prior HCT (HR 2.00), hypogammaglobulinemia (HR 1.51), immune-effector cell-associated neurotoxicity syndrome (ICANS, HR 1.52), and HLH (HR 1.99) were associated with a higher risk of herpesviruses. Independent predictors of fungal infections included prior HCT (HR 1.59), CRS (HR 1.58) and hypogammaglobulinemia (HR 1.40). Idecabtagene vicleucel was associated with a lower risk of herpesvirus and fungal infections (HR 0.39 and 0.44, respectively). ConclusionsIn a large cohort of CAR T-cell therapy recipients, respiratory viral infections were the most common but occurred later, while herpesvirus and fungal infections were less frequent but occurred earlier. Prospective studies investigating prophylaxis and pre-emptive monitoring strategies are needed in this population.

Infection-Associated Flares in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is characterised by generalised immune dysfunction, including infection susceptibility. Infection-associated flares (IAFs) are common and might rapidly self-resolve, paralleling infection resolution, but their specific clinical phenotype is poorly understood. Therefore, we screened 2039 consecutive visits and identified 134 flares, defined as a loss of the lupus low disease activity state (LLDAS), from 1089 visits at risk spanning over multiple follow-up years, yielding an average yearly LLDAS deterioration rate of 17%. Thirty-eight IAFs were isolated from the total flares and were mostly related to bacterial and herpesvirus infections. When compared to other flares (OFs; n = 98), IAFs showed no milder patterns of organ involvement and similar rates of long-term damage accrual, as estimated by conventional clinimetrics. Arthritis in IAFs was more severe than that in OFs [median (interquartile range) DAS-28 2.6 (2.3–4.1) vs. 2.0 (1.6–2.7); p = 0.02]. Viral IAFs were characterised by atypically lower levels of anti-DNA antibodies (p &lt; 0.001) and possibly abnormally high complement levels when compared to flares of different origin. These data suggest that IAFs are of comparable or even higher severity than OFs and may subtend distinct pathophysiological mechanisms that are poorly tackled by current treatments. Further research is needed to confirm these data.

Computational design of prefusion-stabilized Herpesvirus gB trimers.

In the absence of effective vaccines, human-infecting members of the Herpesvirus family cause considerable morbidity and mortality worldwide. Herpesvirus infection relies on receptor engagement by a gH/gL glycoprotein complex which induces large-scale conformational changes of the gB glycoprotein to mediate fusion of the viral and host membranes and infection. The instability of all herpesvirus gBs have hindered biochemical and functional studies, thereby limiting our understanding of the infection mechanisms of these pathogens and preventing vaccine design. Here, we computationally stabilized and structurally characterized the Epstein-Barr virus prefusion gB ectodomain trimer, providing an atomic-level description of this key therapeutic target. We show that this stabilization strategy is broadly applicable to other herpesvirus gB trimers and identified conformational intermediates supporting a previously unanticipated mechanism of gB-mediated fusion. These findings provide a blueprint to develop vaccine candidates for these pathogens with major public health burden.

Upadacitinib in Adolescents With Moderate to Severe Atopic Dermatitis

The Measure Up 1, Measure Up 2, and AD Up studies demonstrated the efficacy and adverse events of upadacitinib through 52 weeks in adults and adolescents with atopic dermatitis (AD); however, longer-term outcomes (longer than 1 year) in adolescents have not previously been available. To evaluate the efficacy and adverse events of upadacitinib in adolescent patients with moderate to severe AD through 76 weeks. The Measure Up 1, Measure Up 2, and AD Up trials are ongoing double-blind, placebo-controlled phase 3 randomized clinical trials including adolescents (aged 12 to 17 years) with moderate to severe AD. Data were collected from August 2018 to April 2022, and data were analyzed from June 2022 to September 2023. Adolescents were randomized 1:1:1 to receive once-daily oral upadacitinib, 15 mg; upadacitinib, 30 mg; or placebo, either alone (Measure Up 1 and Measure Up 2 trials) or with topical corticosteroids (AD Up). At week 16, placebo-treated patients were rerandomized to receive upadacitinib, 15 mg, or upadacitinib, 30 mg, daily. Coprimary end points assessing efficacy included achievement of 75% reduction or more in the Eczema Area and Severity Index Score (EASI-75) from baseline, Validated Investigator Global Assessment for Atopic Dermatitis (vIGA-AD) score of clear (0) or almost clear (1) with 2 grades or more of improvement, and Worst Pruritus Numerical Rating Scale (WP-NRS) improvement of 4 points or greater through week 76 for participants with a WP-NRS score of 4 points or higher at baseline. From all studies, 542 adolescents were included; of these, 284 (52.4%) were female. At week 76, among patients in the Measure Up 1, Measure Up 2, and AD Up trials, EASI-75 was achieved by 89.1%, 84.4%, and 87.8% of adolescents taking upadacitinib, 15 mg, respectively, and by 96.1%, 93.6%, and 82.7% of adolescents taking upadacitinib, 30 mg, indicating maintenance or improvement of EASI-75 across 76 weeks with upadacitinib. Efficacy measured by achievement of vIGA-AD score of 0 or 1 and WP-NRS improvement of 4 points or more from baseline was similarly maintained or improved through week 76 for adolescents taking upadacitinib, 15 mg or 30 mg. Long-term outcomes in Measure Up 1, Measure Up 2, and AD Up participants were consistent with the known adverse event profile of upadacitinib (herpetic infection: 4.0, 1.9, and 1.1 events per 100 patient-years, respectively; creatine kinase elevation: 11.6, 11.0, and 7.1 events per 100 patient-years); no new signals were observed with either dose. In this study assessing 3 randomized clinical trials, long-term treatment of adolescents with moderate to severe AD with upadacitinib demonstrated a favorable benefit-risk profile, with sustained efficacy responses through 76 weeks. Measure Up 1 trial: ClinicalTrials.gov Identifier: NCT03569293; Measure Up 2 trial: NCT03607422; AD Up trial: NCT03568318.

Herpesvirus surveillance in stranded striped dolphins (Stenella coeruleoalba) and bottlenose dolphins (Tursiops truncatus) from Italy with emphasis on neuropathological characterization.

Herpesvirus (HV) is widely distributed among cetacean populations, with the highest prevalence reported in the Mediterranean Sea. In this study, a comprehensive analysis was conducted, including epidemiological, phylogenetic, and pathological aspects, with particular emphasis on neuropathology, to better understand the impact of HV in these animals. Our results show a higher presence of HV in males compared to females, with males exhibiting a greater number of positive tissues. Additionally, adults were more frequently affected by HV infection than juveniles, with no infections detected in calves or neonates. The affected species were striped (Stenella coeruleoalba) and bottlenose dolphins (Tursiops truncatus). The highest positivity rates were observed in the genital system, cerebrum, and skin tissues. Phylogenetic analysis indicated a higher occurrence of Gammaherpesvirus (GHV) sequences but increased genetic diversity within Alphaherpesvirus (AHV). Key neuropathological features included astro-microgliosis (n = 4) and meningitis with minimal to mild perivascular cuffing (n = 2). The presence of concurrent infections with other pathogens, particularly cetacean morbillivirus (CeMV), underscores the complex nature of infectious diseases in cetaceans. However, the presence of lesions at the Central Nervous System (CNS) with molecular positivity for GHV, excluding the involvement of other potential neurotropic agents, would confirm the potential of this HV subfamily to induce neurological damage. Pathological examination identified lesions in other organs that could potentially be associated with HV, characterized by lymphoid depletion and tissue inflammation. These findings enhance our understanding of HV in odontocetes and highlight the need for ongoing research into the factors driving these infections and their broader implications.

Loopy virus or controlled contortionist? 3D regulation of HCMV gene expression by CTCF-driven chromatin interactions.

Three-dimensional chromatin control of eukaryotic transcription is pivotal for regulating gene expression. This additional layer of epigenetic regulation is also utilized by DNA viruses, including herpesviruses. Dynamic, spatial genomic organization often involves looping of chromatin anchored by host-encoded CCCTC-binding factor (CTCF) and other factors, which control crosstalk between promoters and enhancers. Herein, we review the contribution of CTCF-mediated looping in regulating transcription during herpesvirus infection, with a specific focus on the betaherpesvirus, human cytomegalovirus (HCMV).

Genome-wide CRISPR screens identify CLC-2 as a drug target for anti-herpesvirus therapy: tackling herpesvirus drug resistance.

The emergence of drug resistance to virus (i.e., acyclovir (ACV) to herpesviruses) has been termed one of the common clinical issues, emphasizing the discovery of new antiviral agents. To address it, a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening was performed in mouse haploid embryonic stem cells infected with pseudorabies virus (PRV), an α-herpesvirus causing human and pig diseases. The results demonstrated that type 2 voltage-gated chloride channels (CLC-2) encoded by one of the identified genes, CLCN2, is a potential drug target for anti-herpesvirus therapy. CLC-2 inhibitors, omeprazole (OME) and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), can efficiently inhibit infection of multiple herpesviruses in cellulo (i.e., PRV, HSV and EBV), and effectively treat murine herpes simplex encephalitis (HSE). Additionally, DIDS was found to inhibit HSV-1 replication by blocking the PI3K/Akt pathway. Most importantly, both DIDS and OME were able to inhibit ACV-resistant HSV-1 strain infection. The study's findings suggest that targeting host-cell factors such as CLC-2 may be a promising approach to tackling herpesvirus drug resistance. The discovery of CLC-2 as a potential drug target for anti-herpesvirus therapy provides a new direction for the development of novel antiviral agents.

Herpesvirus Antibody Response and Occurrence of Symptoms in Acute and Post-Acute COVID-19 Disease.

Knowledge about the underlying causes of the individual occurrence of symptoms during acute COVID-19 disease and during the post-acute sequelae of COVID-19 is limited. In a German COVID-19 follow-up study, we assessed whether elevated antibody responses to herpesviruses were associated with symptom occurrence in acute COVID-19 disease (n = 96 participants) and during 20 months of follow-up (n = 62 participants). Serum samples were analyzed for their antibodies to herpes simplex virus (HSV)-1 and -2, Epstein-Barr virus (EBV), and Cytomegalovirus (CMV) using fluorescent bead-based multiplex serology. The association of herpesvirus antibodies with symptom occurrence (fatigue, fever, dyspnea, decrease in taste, concentration problems) was assessed using multivariate logistic regression models. High EBV antibody levels were significantly associated with a more than fourfold increased odds of experiencing fatigue during acute COVID-19 disease and during follow-up. High CMV antibody levels were significantly associated with a more than threefold increased odds of experiencing concentration problems and a decrease in taste during the follow-up. The HSV-1 and -2 antibody levels were not elevated in the individuals that experienced symptoms. In conclusion, our findings indicate that herpesvirus infections, specifically EBV and CMV infections, might play a role in symptom development during acute and post-acute COVID-19 disease. It remains to be elucidated whether the elevated EBV and CMV antibodies determined in our study are indicators of herpesvirus reactivation.