Recombinant Epstein-Barr virus Envelope glycoprotein H (gH)

What is the structural composition of EBV glycoprotein H and its functional complex?

EBV glycoprotein H functions as part of a complex with glycoprotein L (gHgL). This complex is essential for viral infectivity regardless of the target cell type . The structure of gH reveals multiple domains that interact with other viral proteins to facilitate membrane fusion. When the gHgL complex interacts with glycoprotein gp42, it forms a tripartite complex (gHgL/gp42) that binds to HLA class II molecules on B cells, activating membrane fusion . The critical regulator of EBV tropism is the gp42 N-terminal domain, which wraps around three gH domains, tethering the HLA-binding domain to gHgL . This structural arrangement is fundamental to understanding how EBV selectively infects different cell types.

For proper function, gH requires complexing with gL for authentic processing, similar to other herpesviruses where the gH-gL complex plays a critical role in penetration . Research has demonstrated that without this proper complex formation, the functionality of gH is significantly compromised.

How does gH differ functionally from other EBV envelope glycoproteins?

Unlike some viral systems where a single multifunctional envelope glycoprotein mediates both receptor binding and membrane fusion, herpesvirus entry, including EBV, employs multiple specialized glycoproteins . In the EBV entry mechanism, each glycoprotein serves a distinct function:

• gp350/220: The most abundant glycoprotein on the virion that promotes viral attachment by binding to CD21 or CD35 receptors

• gH/gL: Essential for infectivity regardless of cell type, involved in the fusion machinery

• gp42: Essential specifically for B cell infection

• gB: Works in concert with gH/gL for membrane fusion

• gM/gN: Important for virion egress and envelope integrity

What distinguishes gH is its central role in the fusion machinery while participating in different complexes that determine cell tropism. Unlike gp350/220, which primarily mediates attachment, or gp42, which is specific to B cell entry, gH functions in both B cell and epithelial cell infection but through different molecular mechanisms .

What experimental evidence confirms the essentiality of gH for EBV infection?

Multiple lines of experimental evidence confirm that gH is absolutely essential for EBV infection:

• Studies using recombinant viruses or knockouts demonstrate that viruses lacking functional gH are non-infectious .

• Neutralizing antibodies targeting gH effectively block viral infection of both B cells and epithelial cells, indicating its critical role regardless of target cell type .

• Experimental systems using functional complementation show that providing gH in trans can rescue infectivity of gH-deficient virions, confirming its direct role in the entry process .

• The observed strong conservation of gH across herpesviruses further supports its essential nature, as proteins critical for viral lifecycle are typically conserved through evolutionary pressure .

• Transfer of vaccine-elicited IgG targeting gH/gL has shown protection against EBV-driven tumor formation in humanized mouse models, demonstrating the critical nature of this protein in the infection process .

What expression systems are most efficient for producing functional recombinant EBV gH?

To produce functional recombinant EBV gH for research applications, several expression systems have been developed with varying advantages:

Mammalian Expression Systems:

• Chinese Hamster Ovary (CHO) cells have proven effective for producing EBV glycoproteins. These cells are FDA-approved for biologics production and efficiently produce complex glycoproteins with proper folding and post-translational modifications . CHO cells have been successfully used to generate virus-like particles (VLPs) incorporating gH/gL with other EBV proteins .

• Human embryonic kidney 293 (HEK293) cells have been used to establish stable cell lines that support not only expression of individual viral proteins but can maintain complete EBV genomes for production of recombinant viruses . This system allows for genetic modifications to study gH function in the context of the whole virus.

Advanced Expression Strategies:

• Alphavirus-derived replicon RNA (repRNA) systems have been developed to efficiently express EBV gH/gL. This approach has been used for vaccine development, with the resulting constructs delivering full-length gH/gL with proper conformation capable of eliciting neutralizing antibodies .

The key consideration for any expression system is that gH must be co-expressed with gL to ensure proper folding, glycosylation, and trafficking to the cell surface. Production in the absence of gL typically results in misfolded and non-functional gH protein .

What are the critical factors in designing constructs for recombinant EBV gH expression?

When designing constructs for recombinant EBV gH expression, researchers must consider several critical factors:

• Co-expression with gL: Since gH depends on gL for proper processing, constructs should enable co-expression of both proteins, either through bicistronic vectors or co-transfection of separate plasmids .

• Signal sequences: Proper signal peptides must be included to ensure correct trafficking through the secretory pathway and exposure on the cell membrane or secretion into the medium.

• Epitope tagging considerations: Tags for purification or detection should be positioned to minimize interference with protein folding or function. C-terminal tags are often preferable as they are less likely to interfere with the signal sequence processing.

• Codon optimization: Adapting the coding sequence to the preferred codon usage of the expression host can significantly improve protein yields.

• Glycosylation sites: Native glycosylation patterns are important for proper folding and immunogenicity. Expression hosts should be selected that can reproduce the necessary glycosylation patterns.

For functional studies, researchers have successfully designed constructs that express gH/gL either alone or in complex with gp42 to study the differential tropism effects . When developing vaccine candidates, full-length constructs encoding the complete gH/gL complex have shown the best results in eliciting neutralizing antibodies .

How can the functionality of purified recombinant gH be validated in research settings?

Validating the functionality of purified recombinant gH is essential to ensure experimental results accurately reflect biological activity. Multiple complementary approaches should be employed:

Structural Validation:

• Western blotting to confirm proper protein size and complex formation with gL

• Glycosylation analysis to verify appropriate post-translational modifications

• Conformational antibody binding assays to ensure native folding

Functional Assays:

• Cell-cell fusion assays: Co-expressing gB, gH/gL (±gp42) in one cell population and appropriate receptors in another can demonstrate fusion activity through reporter systems or microscopic observation .

• Virus neutralization assays: Functional recombinant gH should be capable of eliciting antibodies that neutralize EBV infection when used as an immunogen in animal models .

• Receptor binding assays: Surface plasmon resonance or similar techniques can measure binding of purified gH/gL complexes to their interaction partners.

• Complementation assays: Testing whether the recombinant protein can rescue the infectivity of gH-deficient virions provides strong evidence of functionality .

A comprehensive validation approach using multiple methods provides the most reliable confirmation of proper recombinant gH functionality for subsequent experiments.

How does the gH/gL complex determine EBV's dual tropism for B cells and epithelial cells?

The gH/gL complex serves as a central switch in determining EBV's ability to infect either B cells or epithelial cells through distinct mechanisms:

B Cell Entry:
For B cell infection, the gH/gL complex associates with glycoprotein gp42 to form a tripartite complex (gHgL/gp42). This complex binds to HLA class II molecules on B cells, triggering the fusion machinery . Structural studies have revealed that the gp42 N-terminal domain tethers the HLA-binding domain to gHgL by wrapping around three gH domains . This interaction is essential for B cell fusion and entry.

Epithelial Cell Entry:
In contrast, gp42 inhibits fusion and entry into epithelial cells . For epithelial cell infection, the gH/gL complex functions without gp42, interacting directly with epithelial cell receptors. The specific region of gH that is covered by gp42 in the tripartite complex becomes exposed and available for epithelial receptor binding when gp42 is absent .

This dual tropism mechanism explains why EBV produced in B cells is more infectious for epithelial cells and vice versa. When EBV replicates in B cells, HLA class II molecules bind to and sequester gp42, resulting in virions with reduced gp42 content that preferentially infect epithelial cells. Conversely, EBV produced in epithelial cells (which lack HLA class II) contains more gp42 and preferentially infects B cells .

What experimental approaches can distinguish between gH-mediated fusion with B cells versus epithelial cells?

Researchers have developed several sophisticated approaches to distinguish between gH-mediated fusion mechanisms for different cell types:

Cell-Based Fusion Assays:

• Reporter systems: Cells expressing viral glycoproteins (effector cells) are co-cultured with target cells containing either B cell or epithelial cell receptors. Fusion is quantified using luciferase or GFP reporter systems activated upon cytoplasmic mixing .

• Content mixing assays: Fluorescent dyes that change properties upon mixing of cell contents can measure fusion events in real-time.

Inhibition Studies:

• Selective antibody blocking: Antibodies targeting different epitopes on gH can be used to selectively block B cell or epithelial cell fusion. The E1D1 antibody specifically inhibits epithelial cell fusion while having minimal effect on B cell fusion .

• Mutational analysis: Site-directed mutagenesis of specific regions in gH can identify domains critical for fusion with one cell type but not the other .

Trans-Complementation Experiments:

• Studies have demonstrated that EBV gB and gHgL can mediate fusion and entry in trans (when provided separately) into either epithelial cells or B cells, providing a powerful approach to dissect the requirements for each entry pathway .

Virion Binding and Entry Assays:

• Fluorescently labeled virions allow visualization and quantification of binding, fusion, and entry steps with different cell types. Combined with specific inhibitors or antibodies, these assays can pinpoint the role of gH in each step of the entry process.

What structural elements within gH are critical for its fusion function?

Structural studies have identified several key regions within gH that are critical for its fusion function:

Key Functional Regions:

• Receptor-binding regions: Distinct surfaces on gH interact with different receptors. When complexed with gL and gp42, the gHgL surface that mediates epithelial cell binding becomes masked .

• Fusion-triggering elements: Specific regions undergo conformational changes upon receptor binding that activate the fusion process.

• Interaction sites with gB: gH/gL is believed to activate gB, the actual fusion protein, through direct protein-protein interactions.

Regulatory Elements:
The E1D1 antibody, which selectively inhibits epithelial cell fusion, engages a distinct surface of gHgL compared to the gp42 N-terminal domain (which also inhibits epithelial cell fusion) . This indicates the presence of regulatory elements that can be targeted to modulate fusion in a cell-type specific manner.

Understanding these structural elements is crucial for designing targeted interventions that could selectively block infection of specific cell types or for engineering recombinant gH proteins with modified fusion properties for research applications.

How effective are gH/gL-based vaccine constructs compared to other EBV glycoprotein candidates?

Recent research provides compelling evidence regarding the efficacy of gH/gL-based vaccine constructs compared to other EBV glycoprotein candidates:

Comparative Effectiveness:
Previous EBV vaccine attempts focused on gp350/220 (the most abundant glycoprotein on the virion) have failed to block viral infection in humans, suggesting the need to target other viral envelope glycoproteins . In contrast, gH/gL-based constructs have shown promising results in recent studies.

A direct comparison of vaccine candidates utilizing different EBV glycoproteins revealed that an alphavirus-derived replicon RNA (repRNA) vaccine encoding full-length gH/gL delivered by a cationic nanocarrier (LION™) elicited high titers of neutralizing antibodies that persisted for at least 8 months . This vaccine also stimulated a gH/gL-specific CD8+ T cell response, demonstrating its ability to engage multiple arms of the immune system .

Protection in Animal Models:
The effectiveness of gH/gL-based vaccines has been demonstrated in humanized mouse models, where transfer of vaccine-elicited IgG protected mice from EBV-driven tumor formation and death following high-dose viral challenge . This level of protection provides strong evidence that gH/gL is an ideal immunogen for preventing EBV infection.

Multicomponent Approaches:
Research has also explored incorporating gH/gL into virus-like particles (VLPs) along with other EBV proteins. A study utilizing gH/gL-EBNA1 and gB-LMP2 VLPs demonstrated that these constructs efficiently generated both high neutralizing antibody titers and EBV-specific T-cell responses in mice without requiring adjuvants . This approach may provide broader protection by targeting both the entry mechanism and latent infection.

The data collectively suggest that gH/gL-based vaccines show superior or complementary efficacy compared to the traditional gp350/220 approach, particularly in eliciting neutralizing antibodies that can prevent infection of both B cells and epithelial cells.

What methodologies are most effective for evaluating neutralizing antibody responses against recombinant gH?

Evaluating neutralizing antibody responses against recombinant gH requires sophisticated methodologies that accurately reflect the protein's role in viral entry. The following approaches have proven most effective:

In Vitro Neutralization Assays:

• Cell-type specific infection inhibition: Assays measuring the ability of antibodies to block EBV infection of either B cells or epithelial cells can determine if antibodies target tropism-specific functions of gH/gL .

• Cell-cell fusion inhibition assays: These measure the ability of antibodies to prevent gH/gL-mediated fusion between cells expressing viral glycoproteins and cells expressing appropriate receptors .

• Pseudotyped virus neutralization: Safer than using infectious EBV, this approach uses reporter viruses pseudotyped with EBV glycoproteins to quantify neutralization.

Binding and Functional Characterization:

• Epitope mapping: Techniques such as competition ELISA, peptide arrays, or hydrogen-deuterium exchange mass spectrometry can identify the specific regions of gH targeted by neutralizing antibodies.

• Surface plasmon resonance: This allows measurement of antibody binding kinetics and affinity to recombinant gH/gL complexes.

• Conformational antibody panels: Using panels of conformation-specific antibodies can determine if vaccine-elicited antibodies recognize the functionally relevant forms of gH.

In Vivo Protection Assays:
The gold standard for evaluating neutralizing antibody effectiveness is testing their protective capacity in relevant animal models. Passive transfer of antibodies to humanized mice followed by EBV challenge has demonstrated protection against EBV-driven tumor formation, providing strong evidence for functional neutralization .

For comprehensive evaluation, researchers should employ multiple complementary methods that assess both binding and functional neutralization across different cell types relevant to EBV infection.

How can recombinant gH be engineered to enhance its immunogenicity for vaccine development?

Several strategic engineering approaches can enhance the immunogenicity of recombinant gH for vaccine development:

Structural Modifications:

• Stabilization of conformational epitopes: Introducing disulfide bonds or other stabilizing mutations can lock gH in conformations that better expose neutralizing epitopes.

• Removal of immunodominant non-neutralizing epitopes: Selective modification of regions that distract the immune response away from neutralizing epitopes.

• Glycan engineering: Modifying glycosylation patterns can improve processing by antigen-presenting cells or better expose key neutralizing epitopes.

Delivery Platforms:

• Virus-like particles (VLPs): Incorporating gH/gL onto VLP surfaces has shown excellent immunogenicity without requiring adjuvants . This multimeric display enhances B-cell receptor crosslinking and immune activation.

• Nanoparticle formulations: The LION™ cationic nanocarrier system has proven effective for delivering replicon RNA encoding gH/gL, generating robust neutralizing antibody responses .

• Prime-boost strategies: Heterologous prime-boost approaches using different delivery platforms for the same antigen can enhance both the magnitude and breadth of immune responses.

Immunostimulatory Approaches:

• Fusion to molecular adjuvants: Directly coupling gH to toll-like receptor ligands or cytokines can enhance localized immune activation.

• Co-delivery of T-cell antigens: Including EBV latent antigens like EBNA1 alongside gH/gL can stimulate T-cell help and potentially provide broader protection against EBV-associated diseases .

• Adjuvant selection: Specific adjuvants can be selected to skew immune responses toward desired antibody isotypes or enhanced T-cell responses.

The most promising approach appears to be multicomponent strategies that present gH/gL in its native conformation, potentially alongside other EBV glycoproteins and latent antigens, delivered via platforms that enhance immune recognition and activation.

How can CRISPR-Cas9 gene editing be applied to study gH function in the context of the complete EBV genome?

CRISPR-Cas9 gene editing provides powerful tools for studying gH function within the complete EBV genome, enabling precise manipulations that were previously challenging or impossible:

Methodological Approaches:

• BAC-based recombinant EBV systems: The availability of bacterial artificial chromosome (BAC) clones containing the complete EBV genome provides an ideal substrate for CRISPR-Cas9 editing . The F factor-cloned EBV genome can be modified in E. coli and then transferred to mammalian cells to produce recombinant virus .

• Direct editing in producer cell lines: CRISPR-Cas9 can be used to modify the gH gene directly in 293 cells harboring the EBV genome, which can then be induced to produce recombinant virus .

• Inducible systems: Implementing conditional expression systems allows for studying essential genes like gH by enabling temporal control over gene expression or function.

Specific Applications:

• Domain mapping: Creating precise mutations or deletions in specific gH domains can identify regions critical for different functions (B cell entry, epithelial cell entry, or interactions with other glycoproteins).

• Protein tagging: Adding fluorescent or affinity tags to gH at its endogenous locus allows tracking of the protein during viral replication and entry.

• Complementation studies: Replacing the endogenous gH gene with heterologous gH from other herpesviruses can identify conserved or divergent functions.

• Tropism switching: Engineered mutations in gH that alter its interaction with gp42 can potentially switch viral tropism, allowing experimental control over which cell types can be infected .

The incorporation of reporter genes like green fluorescent protein (GFP) in these recombinant systems provides a powerful means to quantify the effect of gH mutations on viral infectivity , making it possible to assess even subtle phenotypes that might otherwise be difficult to detect.

What are the latest insights from cryo-EM studies on the structure of gH/gL complexes and their interactions?

Cryo-electron microscopy (cryo-EM) has revolutionized our understanding of the structural basis for EBV gH/gL function, providing molecular insights that inform both basic science and therapeutic development:

Structural Architecture of gH/gL Complexes:
Cryo-EM studies have revealed the detailed three-dimensional organization of the gH/gL complex, showing how gL interacts with the N-terminal domain of gH to ensure proper folding and function. The studies demonstrate that gH consists of three distinct domains with specific functions in the fusion process .

Interactions with gp42:
High-resolution structures have elucidated how the gp42 N-terminal domain wraps around the exterior of three gH domains, tethering the HLA-binding domain to gHgL . This interaction is crucial for understanding the molecular basis of EBV tropism, as it explains how gp42 enables B cell infection while inhibiting epithelial cell entry.

Conformational Changes During Fusion:
Cryo-EM has captured different conformational states of the gH/gL complex, providing insights into the structural transitions that occur during the fusion process. These studies suggest that gH/gL undergoes significant rearrangements upon receptor binding that are transmitted to gB to activate its fusion function.

Antibody Binding Sites:
Structural studies of gH/gL in complex with neutralizing antibodies have mapped the precise epitopes targeted by these antibodies. For example, the E1D1 antibody that selectively inhibits epithelial cell fusion has been shown to engage a distinct surface of gHgL compared to the surface engaged by the gp42 N-terminal domain .

These structural insights provide a rational basis for the design of improved recombinant gH constructs with enhanced stability or immunogenicity, as well as for the development of targeted therapeutics that could disrupt specific interactions within the entry complex.

How can single-molecule techniques be applied to study the dynamics of gH-mediated membrane fusion?

Single-molecule techniques offer unprecedented insights into the dynamic processes of gH-mediated membrane fusion, revealing aspects of EBV entry that cannot be captured by bulk or static methods:

Fluorescence-Based Approaches:

• Single-molecule FRET (smFRET): By labeling different domains of gH with appropriate fluorophores, researchers can monitor conformational changes in real-time as gH interacts with other viral glycoproteins or cellular receptors.

• Single-particle tracking: Quantum dot-labeled gH can be tracked on the surface of virions or cells to understand its lateral movement and clustering during the fusion process.

• Super-resolution microscopy: Techniques like STORM or PALM can visualize the nanoscale organization of gH in relation to other viral and cellular components during the fusion process.

Force-Based Techniques:

• Optical tweezers: These can measure the forces generated during gH-mediated membrane interactions and fusion, providing insights into the energetics of the process.

• Atomic force microscopy (AFM): AFM can probe the mechanical properties of gH-containing membranes and measure interaction forces between gH and its binding partners.

Functional Single-Molecule Assays:

• Single-virion fusion assays: Using fluorescently labeled virions and target membranes, researchers can observe individual fusion events triggered by gH/gL complexes.

• Tethered membrane systems: Supported lipid bilayers containing purified gH/gL complexes can be used to study membrane deformations and lipid mixing in controlled environments.

These single-molecule approaches have revealed that gH-mediated fusion is a multi-step process with distinct intermediate states, rather than a simple all-or-none event. They have shown how gH/gL works in concert with gB to orchestrate membrane merger, with gH/gL acting as a fusion regulator that undergoes sequential conformational changes to activate gB, the actual fusion protein .

What are the promising strategies for developing broad-spectrum antivirals targeting conserved features of herpesvirus gH?

Several innovative strategies are emerging for developing broad-spectrum antivirals that target conserved features of herpesvirus gH:

Structure-Based Drug Design Approaches:

• Targeting conserved functional domains: Comparative structural analysis of gH across different herpesviruses has identified highly conserved regions that could serve as targets for small molecule inhibitors with potential broad-spectrum activity.

• Interface inhibitors: Molecules designed to disrupt the critical interaction between gH and gL could prevent proper complex formation and function across multiple herpesviruses .

• Fusion intermediate blockers: Compounds that stabilize pre-fusion conformations or prevent conformational changes required for fusion activation could inhibit multiple herpesviruses that rely on similar fusion mechanisms.

Peptide-Based Inhibitors:

• gH-derived peptides: Synthetic peptides derived from conserved regions of gH that are critical for function can competitively inhibit interactions required for fusion.

• Stapled peptides: These conformationally constrained peptides can mimic structural elements of gH with improved stability and cell penetration properties, potentially blocking fusion with greater efficacy.

Therapeutic Antibody Approaches:

• Cross-reactive antibodies: Identification and engineering of antibodies that recognize conserved epitopes across multiple herpesvirus gH proteins could provide broad protection.

• Antibody cocktails: Combinations of antibodies targeting different conserved epitopes on gH and other glycoproteins could provide synergistic protection against multiple herpesviruses.

Nucleic Acid-Based Strategies:

• siRNA or antisense oligonucleotides: These could be designed to target highly conserved regions of gH mRNA across different herpesviruses.

• CRISPR-Cas13: This RNA-targeting CRISPR system could be programmed to degrade gH transcripts from multiple herpesviruses.

The most promising approaches will likely combine structural insights with advanced delivery systems to ensure that the therapeutic agents can reach sites of herpesvirus infection effectively.

How might recombinant gH be engineered for use in targeted delivery of therapeutics to EBV-infected cells?

Recombinant gH offers unique opportunities for developing targeted delivery systems for therapeutics against EBV-infected cells:

Engineering Approaches:

• Bispecific molecules: Recombinant gH or gH-derived domains can be fused to antibodies or ligands that recognize EBV-infected cells, creating molecules that selectively bind to infected cells.

• gH-toxin conjugates: Fusion of gH domains to protein toxins or small molecule drugs can create targeted therapeutics that specifically eliminate EBV-infected cells.

• Nanoparticle targeting: gH-coated nanoparticles carrying therapeutic payloads can be engineered to selectively deliver drugs, siRNAs, or CRISPR components to infected cells.

Cell-Type Specific Targeting:
Leveraging the natural tropism differences of gH/gL complexes with or without gp42 could enable selective targeting of either B cells or epithelial cells infected with EBV . This approach could be particularly valuable for treating specific EBV-associated malignancies that arise from different cell types.

Combination with Imaging Agents:
Recombinant gH could be dual-labeled with therapeutic and imaging agents to enable theranostic applications, allowing simultaneous visualization and treatment of EBV-infected cells.

Potential Applications:

• Targeting latently infected B cells: In EBV-associated lymphomas, gH-based delivery systems could target therapeutic agents specifically to the malignant B cells.

• Treating epithelial malignancies: For EBV-associated carcinomas, engineered gH variants optimized for epithelial cell binding could deliver therapeutics to these tumors.

• Eliminating viral reservoirs: gH-targeted approaches could potentially help eliminate latently infected cells that serve as reservoirs for viral persistence.

The development of such targeted delivery systems would benefit from the detailed structural understanding of gH and its interactions, allowing rational design of constructs that maintain targeting specificity while incorporating therapeutic payloads.

What are the implications of recent findings on gH-mediated fusion for developing novel membrane fusion technologies beyond virology?

Recent insights into gH-mediated fusion mechanisms have broader implications that extend beyond virology, offering inspiration for novel technologies in multiple fields:

Biomedical Applications:

• Cell-specific delivery systems: The cell type-specific fusion mechanisms of gH could inspire the development of delivery vehicles that selectively fuse with specific target cells, improving the precision of drug or gene delivery.

• Controlled cell fusion for regenerative medicine: Engineered variants of gH could potentially enable controlled cell-cell fusion for applications such as creating hybridomas, cell reprogramming, or tissue engineering.

• Membrane fusion probes: gH-derived peptides or domains could be developed as research tools to study or manipulate membrane dynamics in various biological systems.

Biotechnological Applications:

• Protein delivery across membranes: Understanding how gH orchestrates membrane fusion could lead to novel methods for delivering proteins across cellular membranes, a major challenge in biotechnology.

• Liposome fusion technologies: Insights from gH-mediated fusion could improve liposome-based delivery systems, enabling more efficient fusion with target membranes.

• Biohybrid interfaces: The mechanisms by which gH mediates the merger of viral and cellular membranes could inspire new approaches for creating interfaces between biological and synthetic materials.

Nanotechnology Applications:

• Self-assembling nanomaterials: The ability of gH to undergo dramatic conformational changes could inspire the design of nanomaterials that can switch between different functional states.

• Membrane-interacting nanodevices: Understanding how gH perturbs lipid bilayers could inform the development of nanodevices that can interface with or traverse biological membranes.

The translation of these viral fusion mechanisms into practical technologies will require interdisciplinary approaches combining structural biology, protein engineering, materials science, and nanotechnology, but the potential applications extend far beyond the original virological context.