Microbial and viral antigens

Microbial and viral antigens are molecules, predominantly proteins or polysaccharides, originating from pathogenic organisms such as bacteria, viruses, fungi, and parasites that trigger an immune response in a host (StatPearls, 2023). These antigens are recognized by the immune system's B-cell receptors (antibodies) and T-cell receptors, facilitating the identification and elimination of the invading pathogen (NIH, 2022). In the context of infectious diseases, these antigens are critical targets for both prophylactic vaccines and therapeutic monoclonal antibodies, which aim to neutralize the pathogen or mark it for destruction (Nature Reviews Immunology, 2021). For instance, the spike protein of SARS-CoV-2 is a primary viral antigen targeted by mRNA vaccines to induce protective immunity (CDC, 2023). Beyond their role in immunity, these antigens are essential diagnostic biomarkers used to detect active infections and monitor the efficacy of treatments (World Health Organization, 2020). However, the term is considered a broad category rather than a single specific therapeutic target.

Other names

Pathogen-associated antigensForeign antigensExogenous antigensMicrobial proteinsViral proteinsInfectious agent antigens

Drugs targeting these antigens primarily work through neutralization, where antibodies bind to the antigen to prevent pathogen entry into host cells, or through opsonization, which marks the pathogen for destruction by phagocytes (StatPearls, 2023). Vaccines utilize these antigens to stimulate the production of memory B and T cells, providing long-term adaptive immunity (NIH, 2022).