Streptococcus mutans activates the AIM2, NLRP3 and NLRC4 inflammasomes in human THP-1 macrophages

Abstract

Streptococcus mutans triggers an early-stage immune response via a chain of events that leads to the activation of immune component, interleukin-1β. A group of academics from Korea’s Pusan National University, led by Jin Chung, tested the response of human immune cell cultures to infection with S. mutans—a common oral bacteria that can cause systemic disease if it enters the bloodstream. The group found that S. mutans infection leads to the activation of protein signaling complexes known as inflammasomes, which in turn activate an enzyme known as caspase-1. Caspase-1 then activates interleukin-1β, a pro-inflammatory molecule that forms part of a host’s defenses against pathogens. The team also identified that ATP release, ion depletion, and integrity of intracellular enzyme containers, also impacted inflammasome activation. This study offers insights into the immune response against S. mutans and may inform future investigations into systematic oral bacteria infections.

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