Viral Antigens

Key Biological Properties: WNV is an enveloped virus with icosahedral symmetry . Its genome is approximately 11,000 nucleotides long and codes for three structural proteins and seven nonstructural proteins .

Expression Patterns and Tissue Distribution: WNV primarily infects birds, which serve as the natural hosts . The virus is transmitted to humans and other mammals through the bites of infected mosquitoes, particularly those of the genus Culex . In humans, the virus can be found in the blood and cerebrospinal fluid .

Primary Biological Functions: WNV’s primary function is to replicate within host cells. It can cause West Nile fever and, in severe cases, neurological diseases such as encephalitis and meningitis .

Role in Immune Responses and Pathogen Recognition: WNV triggers innate immune responses, including the activation of antiviral effector genes and natural killer (NK) cell signaling pathways . The virus is recognized by the immune system through pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs) .

Mechanisms with Other Molecules and Cells: WNV enters host cells by binding to cell surface receptors and undergoing endocytosis . The viral envelope fuses with cellular membranes, releasing the RNA genome into the cytoplasm .

Binding Partners and Downstream Signaling Cascades: The viral envelope proteins E and M are crucial for receptor binding and membrane fusion . The RNA genome serves as a template for viral protein synthesis and replication .

Regulatory Mechanisms Controlling Expression and Activity: WNV replication is regulated by host cell factors and viral nonstructural proteins . The virus can evade immune responses through various mechanisms, including the inhibition of apoptosis .

Transcriptional Regulation and Post-Translational Modifications: The viral RNA genome is translated into a polyprotein, which is cleaved into individual proteins by viral and host proteases . Post-translational modifications of viral proteins are essential for viral assembly and maturation .

Biomedical Research: WNV serves as a model for studying flavivirus biology and pathogenesis . Research on WNV has led to insights into viral replication, immune evasion, and vaccine development .

Diagnostic Tools: Diagnostic methods for WNV include serological tests to detect specific antibodies and molecular techniques to identify viral RNA .

Therapeutic Strategies: While there is no specific antiviral treatment for WNV, supportive care and experimental therapies are being explored .

Role Throughout the Life Cycle: WNV is maintained in nature through a bird-mosquito-bird transmission cycle . Mosquitoes become infected by feeding on infected birds and can then transmit the virus to humans and other mammals . The virus can persist in mosquito populations through vertical transmission (from adults to eggs) .

WNV’s ability to cause disease varies with the host’s age and immune status. The elderly and immunocompromised individuals are at higher risk of developing severe disease .