Increased monocyte TNF-alpha message stability contributes to trauma patients' increased TNF production

Area of Science:

• Immunology
• Molecular Biology
• Trauma Research

Background:

• Elevated tumor necrosis factor alpha (TNF-alpha) is critical in mediating systemic inflammatory response syndrome (SIRS) post-trauma.
• Monocyte (mphi) TNF-alpha production significantly contributes to this elevation, but underlying mechanisms remain unclear.

Purpose of the Study:

• To elucidate the molecular mechanisms behind increased monocyte TNF-alpha production following trauma.
• To investigate the correlation between TNF-alpha production, mRNA stability, and mortality in trauma patients.

Main Methods:

• Analysis of TNF-alpha mRNA and protein levels in monocytes from trauma patients.
• Assessment of transcriptional and posttranscriptional control of TNF-alpha production.
• In vitro stimulation assays to evaluate mRNA stability and accumulation.

Main Results:

• All trauma patients exhibited increased monocyte TNF-alpha mRNA and protein levels.
• In most patients, TNF-alpha production was linked to preactivation by trauma mediators.
• A subset of patients (57% mortality) showed aberrantly increased TNF-alpha mRNA stability, leading to prolonged protein production.

Conclusions:

• Increased TNF-alpha mRNA stability in monocytes is a novel mechanism contributing to elevated TNF-alpha protein levels and mortality post-trauma.
• This finding highlights a specific molecular pathway linked to severe SIRS and poor outcomes in trauma patients.