December 1994

The Local Role of Tumor Necrosis Factor α in the Modulation of Neutrophil Function at Sites of Inflammation

Author Affiliations

From the Departments of Surgery (Drs Yee and Christou) and Microbiology (Dr Christou), Royal Victoria Hospital, McGill University, Montréal, Quebec.

Arch Surg. 1994;129(12):1249-1255. doi:10.1001/archsurg.1994.01420360039004

Objective:  To examine the hypothesis that tumor necrosis factor α (TNF-α) is an important local modulator of neutrophil function in the inflammatory microenvironment.

Design:  In vitro studies of host defense.

Patients:  A volunteer sample of healthy subjects.

Intervention:  Exudative neutrophils were collected from skin-blister chambers and functionally compared with blood neutrophils.

Methods:  Tumor necrosis factor α levels at sites of inflammation and neutrophil exudation were determined and compared with serum concentrations. Flow cytometry was used to evaluate neutrophil microbicidal activity and N-formyl-methionyl-leucyl-phenylalanine—induced changes in intracellular calcium and superoxide production. In vitro TNF-α was used to evaluate the nature and dose response of TNF-α–induced changes in neutrophil function.

Results:  Exudative neutrophils have an increased responsiveness to subsequent N-formyl-methionyl-leucyl-phenylalanine stimulation, as determined by changes in intracellular calcium. Microbicidal activity and superoxide production are also up-regulated compared with circulating neutrophils. The exudative microenvironment contains TNF-α at local levels that are capable of significantly enhancing neutrophil host defense.

Conclusions:  Tumor necrosis factor α may serve to enhance neutrophil function at sites of inflammation. Neutrophils become more cytotoxic and have an enhanced ability to respond to weak environmental signals.(Arch Surg. 1994;129:1249-1255)