Chikungunya virus envelope glycoproteins E1 and E2 (CHIKV E1/E2)

The Chikungunya virus (CHIKV) structural proteins E1 and E2 are the primary components of the viral envelope, organized into 80 trimeric spikes on the virion surface (NIH, 2020). E2 is a glycoprotein responsible for attachment to host cell receptors, such as Matrix Remodeling-Associated Protein 8 (Mxra8), while E1 is a class II fusion protein that mediates the pH-dependent fusion of the viral envelope with the host endosomal membrane (NIH, 2020; PLOS, 2019). Together, these proteins facilitate viral entry and are the principal targets for neutralizing antibodies during infection (NIH, 2026). Because of their essential role in the viral life cycle, E1 and E2 are the primary focus for vaccine development and therapeutic interventions, including monoclonal antibodies and small-molecule entry inhibitors (NIH, 2024). Mutations in these proteins, notably the E1-A226V substitution, have been shown to enhance viral transmission by adapting the virus to different mosquito vectors (NIH, 2020). Targeting the E1/E2 complex aims to neutralize the virus and prevent the severe, often chronic, polyarthralgia and febrile illness characteristic of Chikungunya fever (NIH, 2024). Current therapeutic research includes the development of neutralizing monoclonal antibodies like CHK-152 and the use of live-attenuated vaccines like Ixchiq to elicit a protective immune response against these proteins (FDA, 2023; PLOS, 2019). Challenges in targeting these proteins include the potential for viral escape through rapid mutation and the need to address the persistent inflammatory symptoms that can remain after viral clearance (NIH, 2026).

Other names

Chikungunya virus structural proteins E1/E2CHIKV E1/E2 complexCHIKV spike proteinsCHIKV envelope proteinsE1-E2 heterodimer

Inhibition of viral entry by blocking E2-mediated receptor binding or E1-mediated membrane fusion (NIH, 2020; PLOS, 2019).