Immune memory to Sudan virus: comparison between two separate disease outbreaks.

Area of Science:

• Immunology
• Virology
• Infectious Diseases

Background:

• Ebolavirus infection recovery is linked to adaptive immune responses.
• Lack of robust immune response correlates with non-survival.
• A complete protective immune profile remains undescribed.

Purpose of the Study:

• To investigate cellular memory immune responses in Ebolavirus survivors.
• To analyze immune recall responses following Sudan virus (SUDV) infection.
• To explore cross-reactivity between different ebolaviruses.

Main Methods:

• Blood samples from SUDV survivors were stimulated with inactivated and recombinant SUDV/Ebola virus (EBOV) GP.
• ELISA and neutralization assays measured anti-SUDV IgG titers.
• Cytokine expression was analyzed in whole blood cultures.

Main Results:

• Recall responses indicating immune memory were detected in both survivor cohorts.
• Neutralizing SUDV-specific IgG activity was present.
• Humoral and cell-mediated cross-reactivity to EBOV was observed.

Conclusions:

• Immune responses in survivors show persistent antigen recognition.
• Outbreak-specific memory responses may differ, highlighting the need for outbreak-specific studies.
• Cross-reactive immune recognition suggests potential for cross-protective ebolavirus vaccines.