Increased circulating interleukin-12 (IL-12) p40 in pulmonary sarcoidosis.

Abstract

In sarcoidosis, a T helper 1 (Th1) response is an essential event and the up-regulation of interleukin-12 (IL-12) has been detected in affected disease sites. In order to investigate the clinical usefulness of circulating IL-12, we measured the serum concentrations of IL-12 by ELISA and performed immunohistochemistry using specific MoAbs for IL-12 in the lungs and scalene lymph nodes of patients with sarcoidosis. The serum concentration of IL-12 p40 was detectable in all 45 patients with pulmonary sarcoidosis and 18 normal controls, whereas that of IL-12 p70 was undetectable. The serum concentrations of IL-12 p40 in pulmonary sarcoidosis were significantly higher than those of the normal controls, especially in cases with abnormal intrathoracic findings detected by chest roentogenogram. The serum concentrations of interferon-gamma (IFN-gamma) also increased compared with those of normal controls and there was a significant positive correlation between the serum concentrations of IL-12 p40 and IFN-gamma. Furthermore, serum angiotensin-converting enzyme (ACE) and lysozyme, which are known to be useful markers for disease activity in sarcoidosis, correlated well with the serum concentrations of IL-12 p40. The positive 67Ga scan group (for lung field) had significantly elevated serum IL-12 p40 levels compared with those of the negative group. No bioactivity of IL-12 p70 was detected in three sarcoid cases sera by using the IL-12 responsive cell line. Finally, the immunohistochemical approach revealed that IL-12 p40 was expressed in the epithelioid cells and macrophages of sarcoid lungs and lymph nodes. We concluded that the production of IL-12 p40 was far greater in the sera and we have demonstrated this to be a useful clinical marker for disease activity and the Th1 response in pulmonary sarcoidosis.

• Authors: K Shigehara, N Shijubo, M Ohmichi, K Kamiguchi, R Takahashi, S Morita-Ichimura, T Ohchi, T Tatsuno, Y Hiraga, S Abe, N Sato
• Journal: Clinical and experimental immunology (Clin Exp Immunol) Vol. 132 Issue 1 Pg. 152-7 (Apr 2003) ISSN: 0009-9104 [Print] England
• PMID: 12653850 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Biomarkers
• Immunoglobulin Isotypes
• Interleukin-12
• Interferon-gamma
• Muramidase
• Peptidyl-Dipeptidase A

Topics

• Analysis of Variance
• Biomarkers (analysis, blood)
• Case-Control Studies
• Cell Line
• Enzyme-Linked Immunosorbent Assay (methods)
• Epithelioid Cells (immunology)
• Female
• Humans
• Immunoglobulin Isotypes (analysis, blood)
• Immunohistochemistry (methods)
• Interferon-gamma (biosynthesis, blood)
• Interleukin-12 (analysis, blood)
• Lung (diagnostic imaging, immunology)
• Lymph Nodes (immunology)
• Macrophages (immunology)
• Male
• Middle Aged
• Muramidase (blood)
• Peptidyl-Dipeptidase A (blood)
• Radionuclide Imaging
• Sarcoidosis, Pulmonary (diagnostic imaging, immunology)
• Th1 Cells (immunology)