Medwire News: The biomarker monocyte chemoattractant protein (MCP)-1 has emerged as a potentially useful predictor of chronic obstructive pulmonary disease (COPD) in heavy smokers, study results show.

Measuring serum levels of MCP-1, the researchers were able to differentiate between healthy smokers and those with COPD and also predict severity of disease in COPD patients.

One of the hallmarks of COPD is an abnormal inflammatory response of the lungs to noxious particles or gases, explain study author Meng-Chih Lin (Chang Gung Memorial Hospital, Kaohsiung, Taiwan) and colleagues in the journal Respirology.

Inflammatory cells involved in COPD include neutrophils, macrophages, and lymphocytes, which release inflammatory mediators that interact with structural cells in the airways and the lung parenchyma.

Some of these inflammatory mediators, which include chemokines, cytokines, and growth factors, are increased in COPD patients, but their precise role is still unclear.

To investigate, Lin and colleagues recruited 100 patients with stable COPD who were all heavy smokers with more than 10 pack-years smoking history and were over 40 years of age. They matched these patients on a 1:2 basis to 50 heavy smokers who underwent physical and spirometric examination but had no underlying medical diseases.

Levels of five serum inflammatory mediators were measured: growth-related oncogene-α, interleukin-8, tumour necrosis factor-α, matrix metalloproteinase-9, and MCP-1.

The only reliable biomarker that differed significantly between patients and controls was MCP-1 with concentrations of 297.5 pg/ml and 183.3 pg/ml, respectively.

In addition, serum MCP-1 levels correlated significantly with FEV1 percent predicted and the 6-minute-walking-distance test 6MWD in both univariate and multivariate analysis.

Lin et al say that MCP-1 could act in a number of ways, and even hint at possible treatments.

“MCP-1 is a CC chemokine that mediates its effects via the CCR2 receptor, which is the specific receptor for MCP-1 and is expressed by monocytes, macrophages, and T lymphocytes,” they explain.

“Macrophages seem to have a crucial role in COPD… therefore, blocking CCR2 could be a useful therapeutic strategy.”

MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a part of Springer Science+Business Media. © Current Medicine Group Ltd; 2009

Free abstract