Elevated TNF-alpha production by peripheral blood monocytes of weight-losing COPD patients

Am J Respir Crit Care Med. 1996 Feb;153(2):633-7. doi: 10.1164/ajrccm.153.2.8564110.


The inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-1-beta (IL-1 beta), have been associated with accelerated metabolism and protein turnover following exogenous administration in normal humans. We hypothesized that these inflammatory cytokines might contribute to the weight-losing process in patients with chronic obstructive pulmonary disease (COPD). COPD patients were identified prospectively as "weight losers" (WL; n = 10) if they reported > 5% weight loss during the preceding year or as "weight stable" (WS; n = 10) if their body weight fluctuated < or = 5%. Age-matched healthy volunteers were selected as the control group (C; n = 13). Monocytes were isolated from a peripheral blood sample, cultured, and exposed to lipopolysaccharide (LPS). The concentration of TNF-alpha and IL-1 beta in the monocyte supernatant was measured using a four layer enhanced ELISA. No significant difference in LPS-stimulated IL-1 beta production was found in the three study populations. However, LPS-stimulated TNF-alpha production (mean [range] ng/ml) by monocytes was significantly higher in the WL COPD patients (20.2 [6.3 to 44.8]), compared with WS patients (6.9 [1.5 to 16.6]), and C subjects (5.7 [0 to 61.8]). This difference was not maintained at 6 mo follow-up in the absence of ongoing weight loss. Definition of a causal relationship between TNF-alpha production and weight loss will require further understanding of the relationship between energy metabolism and TNF-alpha production in these patients.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Cells, Cultured
  • Energy Metabolism
  • Female
  • Forced Expiratory Volume
  • Humans
  • Interleukin-1 / metabolism
  • Lipopolysaccharides / pharmacology
  • Lung Diseases, Obstructive / blood*
  • Lung Diseases, Obstructive / physiopathology
  • Male
  • Middle Aged
  • Monocytes / metabolism*
  • Tumor Necrosis Factor-alpha / biosynthesis*
  • Vital Capacity
  • Weight Loss*


  • Interleukin-1
  • Lipopolysaccharides
  • Tumor Necrosis Factor-alpha