Cytokines in acute chikungunya

Area of Science:

• Virology
• Immunology
• Epidemiology

Background:

• Chikungunya (CHIKV) is a painful arbovirus illness causing musculoskeletal symptoms.
• Previous studies, including a 2006 Indian epidemic, have documented CHIKV's impact.
• This study presents serum cytokine profiles in CHIKV patients within one month of illness onset.

Purpose of the Study:

• To analyze serum cytokine profiles in acute chikungunya patients.
• To correlate cytokine levels with clinical features and antibody responses.
• To investigate factors influencing symptom resolution in CHIKV infection.

Main Methods:

• Analyzed serum cytokines (IFN-α, -β, -γ, CXCL-10, TNF-α, IL-1β, IL-6, IL-13, MCP-1, IL-4, IL-10) using ELISA in 132 CHIKV patients.
• Tested for anti-CHIKV IgM and IgG antibodies via immunochromatography and immunofluorescence.
• Included healthy controls from a prior community survey.

Main Results:

• Elevated levels of IFN-α, IFN-β, IFN-γ, CXCL-10, and IL-1β were observed in the early acute phase.
• Cytokines like TNF-α, MCP-1, IL-4, IL-6, and IL-10 peaked in the extended symptomatic phase and remained high post-recovery.
• Higher Interferon (IFN) and Interleukin-4 (IL-4) levels correlated with anti-CHIKV IgG seropositivity; elderly patients showed similar cytokine profiles to younger ones.

Conclusions:

• An intense cytokine response is characteristic of acute and persistent CHIKV infection, extending into the recovery phase.
• Delayed musculoskeletal symptom resolution is associated with early persistent IgM, lower IgG anti-CHIKV antibodies, and a Th2 cytokine phenotype.
• Specific cytokine patterns, including high TNF-α, IL-6, IL-13 with low IgM, were noted in patients recovering within one month.