Immunoglobulin M against SARS-CoV-2 spike protein or nucleocapsid protein (IgM against SARS-CoV-2 S or N protein)

Immunoglobulin M (IgM) against SARS-CoV-2 spike protein or nucleocapsid protein is an early immune antibody produced in response to infection with SARS-CoV-2, the virus responsible for COVID-19. The spike (S) protein is a viral surface protein essential for virus entry into human cells by binding ACE2 receptors, while the nucleocapsid (N) protein packages the viral RNA genome within the virion[1][2][5][6][7][8]. Detection of IgM against these antigens serves primarily as a diagnostic marker of recent SARS-CoV-2 infection. These antibodies can bind to their respective antigens; binding to the spike protein may have neutralizing effects, while detection of nucleocapsid-reactive IgM is primarily used for immunodiagnostic purposes. Clarification: - This entry is not a canonical biomolecular therapeutic target (i.e., it is not a receptor, enzyme, transporter, etc.), but rather describes a class of antibodies generated against viral antigen targets[1][2][5][7][8]. - For target tables, the actual therapeutic targets would be "SARS-CoV-2 spike protein" or "SARS-CoV-2 nucleocapsid protein" themselves, not the antibodies generated against them. - The current description is thus incorrect for a canonical therapeutic target; it instead refers to an immune response product or biomarker. If you require structured information about the individual antigens (i.e., "SARS-CoV-2 spike protein" as a drug target or "SARS-CoV-2 nucleocapsid protein" as a biomarker), those should be queried separately.

Other names

Anti-SARS-CoV-2 spike IgMAnti-SARS-CoV-2 nucleocapsid IgMSARS-CoV-2 spike-specific IgMSARS-CoV-2 nucleocapsid-specific IgM

Binds to and potentially neutralizes SARS-CoV-2 virus (spike protein: blocks attachment/fusion; nucleocapsid: primarily diagnostic marker). Opsonization (facilitates phagocytosis). Complement activation.