Antibody-Dependent Enhancement (ADE) is a complex immunological phenomenon where virus-specific antibodies, rather than neutralizing the virus, enhance its entry into host cells and amplify its replication. ADE can occur in the context of natural infections and vaccinations, leading to heightened disease severity. This phenomenon has been observed in various viral infections, including respiratory syncytial virus (RSV), dengue, and HIV, and has been a subject of intense scrutiny in the context of SARS-CoV-2, the virus responsible for COVID-19.
The historical context of ADE provides critical insights into its mechanisms and implications. One notable example is the RSV vaccine trials in the 1960s. Vaccinated children who later encountered natural RSV infection experienced more severe respiratory illness compared to unvaccinated children. This was attributed to ADE, where vaccine-induced antibodies facilitated enhanced viral entry and immune activation (Kim et al., 1969). Understanding the diverse mechanisms of ADE, its implications for vaccine development, and its potential occurrence in SARS-CoV-2 infection is crucial. This comprehensive analysis aims to elucidate the different types of ADE, evidence of ADE in SARS-CoV-2, and the risks and proposed mitigation strategies associated with ADE in COVID-19 vaccines.
Hellbound and Down 