HCMV gB Specific Neutra™ Antibody Products
Product listHuman cytomegalovirus (HCMV), a widespread betaherpesvirus, possesses an intricate double-stranded DNA genome containing Human cytomegalovirus (HCMV), a widespread betaherpesvirus, possesses an intricate double-stranded DNA genome containing numerous genes that alter host immune defenses and promote viral persistence. While generally causing mild or asymptomatic infections in healthy hosts, HCMV induces severe clinical manifestations in immuno-compromised populations, including transplant recipients, HIV/AIDS patients, and infants with congenital infections. The virus maintains lifelong latency through periodic reactivation cycles. Among its array of surface glycoproteins, glycoprotein B (gB) emerges as the most abundant viral envelope component, critically mediating cellular attachment and membrane fusion processes essential for infectivity.
HCMV gB Structure
HCMV gB, encoded by open reading frame UL55, is a multifunctional class III membrane fusion protein exceeding 900 amino acids in length. Its structural organization comprises three principal regions: an N-terminal ectodomain housing immunodominant epitopes, a conserved fusion loop critical for lipid bilayer merger, and C-terminal transmembrane anchors securing the protein within viral envelopes. These elements collectively form intricate tertiary structures, enabling receptor engagement and interprotein interactions. gB is well conserved across HCMV strains with a mean identity of 96% at the amino acid level. The high degree of conservation of gB across herpesviruses underscores its essential role in viral infection and pathogenesis.
Fig. 1 Domain architecture of HCMV gB.1, 3
Role of gB in Virus Entry
gB orchestrates HCMV's primary cellular invasion through coordinated membrane fusion events. Following initial receptor binding, gB undergoes structural rearrangements that catalyze viral envelope integration with host cell membranes, enabling capsid release into the cytoplasm. Experimental evidence confirms gB's essentiality through mutagenesis studies - deletion or functional impairment completely abolishes infectivity. This fusion cascade requires synergistic interactions with auxiliary viral glycoproteins and cellular receptors, forming multicomponent entry complexes that ensure efficient penetration.
Fig. 2 Models of HCMV entry into human cells with the fusogenic activity of gB.2, 3
Role of gB in Virus Cell-to-Cell Spread
Beyond primary infection, gB facilitates direct intercellular transmission through specialized membrane structures. This transmission mode enables immune evasion by circumventing antibody-rich extracellular environments. Mechanistic analyses reveal gB's involvement in virological synapse formation - specialized junctions mediating viral transfer between adjacent cells. Such cell-to-cell spread proves particularly critical during latency reactivation events, permitting viral propagation despite established humoral immunity.
Importance of gB for Virus Pathogenesis
gB's dual functionality in cellular invasion and dissemination establishes its central role in HCMV-related pathologies. Immunosuppressed patients experience exacerbated disease progression due to uncontrolled gB-mediated viral spread. Congenital infections frequently cause neurological impairments stemming from gB-dependent transplacental transmission and neural cell tropism. These pathogenic mechanisms position gB as a prime therapeutic target, with current strategies focusing on fusion inhibition and epitope-specific neutralization.
Antibodies Targeting HCMV gB
Host humoral responses against HCMV predominantly target gB's antigenic domains, particularly neutralizing antibodies directed against AD-1, AD-2, and AD-5 epitopes. Monoclonal antibodies binding these regions demonstrate variable neutralization capacities dependent on epitope accessibility and structural conformation. They can bind to gB and block its ability to mediate viral entry, thus preventing infection and limiting viral spread. Beyond therapeutic applications, gB-specific antibodies serve diagnostic purposes through ELISA-based detection systems and viral load monitoring platforms. Emerging technologies incorporate these antibodies into multiplex biosensors for rapid clinical diagnostics.
Fig. 3 Neutralizing epitopes in HCMV gB.4
Creative Biolabs provides a wide range of high-quality anti-HCMV gB antibody products, which undergo extensive validation to ensure batch consistency and target specificity. These research-grade reagents support diverse applications ranging from fundamental virological studies to therapeutic development initiatives, facilitating both mechanistic insights and clinical management advancements for HCMV infections.
REFERENCES
- Pötzsch, Sonja, et al. "B cell repertoire analysis identifies new antigenic domains on glycoprotein B of human cytomegalovirus which are target of neutralizing antibodies." PLoS pathogens 7.8 (2011): e1002172. https://doi.org/10.1371/journal.ppat.1002172
- Gerna, Giuseppe, Anna Kabanova, and Daniele Lilleri. "Human cytomegalovirus cell tropism and host cell receptors." Vaccines 7.3 (2019): 70. https://doi.org/10.3390/vaccines7030070
- Distributed under Open Access license CC BY 4.0, without modification.
- Chandramouli, Sumana, et al. "Structure of HCMV glycoprotein B in the postfusion conformation bound to a neutralizing human antibody." Nature communications 6.1 (2015): 8176. Distributed under Open Access license CC BY 4.0. The image was modified by extracting and using only part of the original image. https://doi.org/10.1038/ncomms9176
