Interleukin 1 receptor blockade attenuates the host inflammatory response.

Area of Science:

• Immunology
• Inflammation Biology
• Metabolic Regulation

Background:

• Cytokines like IL-1, TNF-alpha, and IL-6 mediate host responses to injury, including weight loss and acute-phase protein synthesis.
• The precise role of IL-1 in specific tissue catabolism during inflammation remains incompletely understood.

Purpose of the Study:

• To investigate if blocking IL-1 receptor activity in vivo can inhibit catabolic host changes during inflammation.
• To determine the specific contribution of IL-1 to weight loss, body composition alterations, and acute-phase responses in an inflammatory model.

Main Methods:

• Mice were passively immunized with a monoclonal antibody against the IL-1 receptor before inducing a sterile abscess with turpentine.
• Body weight, body composition, plasma amyloid P, plasma albumin, circulating corticosterone, and plasma IL-6 levels were assessed.
• Comparisons were made with mice treated with polyclonal antisera against tumor necrosis factor alpha.

Main Results:

• Anti-IL-1 receptor antibody treatment prevented weight loss and preserved lean tissue and fat mass.
• This blockade significantly reduced plasma amyloid P and IL-6 levels.
• Treatment with anti-TNF-alpha antisera did not prevent weight loss or hepatic acute-phase protein changes.

Conclusions:

• IL-1 plays a central role in orchestrating weight loss and body compositional changes during inflammation.
• IL-1 contributes to the induction of IL-6 and acute-phase protein synthesis in response to inflammatory stimuli.
• Targeting IL-1 may offer a strategy to mitigate detrimental catabolic effects of inflammation.