Mpox-Specific Immune Responses Elicited by Vaccination or Infection in People With HIV

Area of Science:

• Immunology
• Virology
• Public Health

Background:

• People with human immunodeficiency virus (PWH) faced higher risks during the mpox outbreak.
• Understanding immune responses in PWH is crucial for outbreak control and prevention.

Purpose of the Study:

• To investigate cellular and humoral immune responses to mpox infection and smallpox vaccination in men who have sex with men, including PWH.
• To assess the cross-reactivity and durability of smallpox vaccination-induced immunity against mpox virus.

Main Methods:

• Studied immune responses in a cohort of men who have sex with men, including PWH, following mpox infection or modified vaccinia Ankara (MVA) vaccination.
• Analyzed B cell, CD4 T cell, and CD8 T cell responses.

Main Results:

• Both mpox infection and MVA vaccination induced mpox-specific immune responses in PWH.
• Individuals with prior childhood smallpox vaccination showed cross-reactive immune responses to mpox virus.
• Immune responses involved B cells, CD4 T cells, and CD8 T cells.

Conclusions:

• Smallpox vaccination, including childhood vaccination, can elicit cross-reactive immunity to mpox virus.
• Immune responses to mpox are durable and present even in PWH with controlled HIV.
• Findings enhance understanding of orthopox virus immunity and vaccination strategies.