Cytokine modulation correlates with severity of monkeypox disease in humans.

Background: Human monkeypox is a zoonotic disease endemic to parts of Africa. Similar to other orthopoxviruses, virus and host have considerable interactions through immunomodulation. These interactions likely drive the establishment of a productive infection and disease progression, resulting in the range of disease presentations and case fatality rates observed for members of the Orthopoxvirus genus.

Objectives: Much of our understanding about the immune response to orthopoxvirus infection comes from either in vitro or in vivo studies performed in small animals or non-human primates. Here, we conducted a detailed assessment of cytokine responses to monkeypox virus using serum from acutely ill humans collected during monkeypox active disease surveillance (2005-2007) in the Democratic Republic of the Congo.

Study Design: Nineteen serum samples that were from patients with confirmed monkeypox virus infections were selected for cytokine profiling. Cytokine profiling was performed on the Bio-Rad Bioplex 100 system using a 30-plex human cytokine panel.

Results: Cytokine profiling revealed elevated cytokine concentrations in all samples. Overproduction of certain cytokines (interleukin [IL]-2R, IL-10, and granulocyte macrophage-colony stimulating factor were observed in patients with serious disease (defined as >250 lesions based on the World Health Organization scoring system).

Conclusions: The data suggest that cytokine modulation affects monkeypox disease severity in humans.