Serum levels of soluble CD163 correlate with the inflammatory process in coeliac disease

In coeliac disease, following the introduction of a gluten-free diet, monitoring mucosal disease activity requires repeated small intestinal biopsies. If a test measuring a circulating inflammatory marker was available, this would be clinically valuable. To determine if levels of soluble CD163, a scavenger receptor shed by tissue macrophages, correlated with the inflammatory lesion in coeliac disease. Serum samples were collected from 131 patients with untreated coeliac disease, 40 patients with treated coeliac disease, 92 non-coeliac disease control subjects and 131 healthy controls. A capture enzyme linked immunosorbance assay was established to measure levels of soluble CD163 in sera. The extent of the histological lesion in coeliac biopsies was assessed using a Marsh grading system. Levels of CD163 in untreated coeliac subjects were significantly elevated when compared with the treated coeliac patients, the disease control group and the healthy control subjects (P < 0.0001 in each instance). Moreover, coeliac patients with the most marked histological lesion (Marsh 3) had significantly higher levels of soluble CD163 than patients with Marsh grade 2 lesions (P < 0.0004), with grade 1 lesions (P < 0.0001) and grade 0 lesions (P < 0.0001). Measurement of soluble CD163 may be a useful method of monitoring the inflammatory lesion in coeliac disease.