Clinical bottom line
Serum soluble CD206 (sCD206), a cleaved form of the macrophage mannose receptor, is emerging as a putative biomarker for macrophage activation in alcoholic hepatitis (AH). Elevated sCD206 levels may reflect hepatic macrophage activation, a key driver of inflammation and disease progression in AH. Preliminary evidence suggests sCD206 could aid in disease monitoring and risk stratification, but its clinical utility remains investigational and requires validation in larger, prospective cohorts. At present, sCD206 measurement should be considered hypothesis-generating rather than a routine clinical tool.
What the evidence shows
The macrophage mannose receptor (CD206) is expressed on alternatively activated macrophages involved in tissue remodeling and immune regulation. A soluble form of CD206 circulates in serum, released by proteolytic cleavage during macrophage activation. Rødgaard-Hansen et al. (2013) first demonstrated that sCD206 is detectable in human serum and elevated in critical illness, suggesting its potential as a biomarker of macrophage activation. Although their study was not specific to liver disease, it established the biological plausibility of sCD206 as a marker of systemic macrophage activity.
In the context of liver disease, macrophage activation is central to the pathogenesis of alcoholic hepatitis, driving inflammation, fibrosis, and hepatocellular injury. While other macrophage activation markers such as soluble CD163 have been studied more extensively in chronic hepatitis C and alcoholic hepatitis (El Deeb et al., 2018; Kriek et al., 2026), sCD206 offers a complementary marker reflecting a distinct macrophage activation phenotype.
Nielsen et al. (2026) recently highlighted sCD206 as a promising biomarker in idiopathic pulmonary fibrosis, supporting its broader relevance in fibrotic inflammatory diseases. Although direct data on sCD206 in alcoholic hepatitis remain sparse, the mechanistic rationale and parallels with other macrophage activation syndromes support its putative role.
Other macrophage activation markers, such as soluble CD25 and macrophage migration inhibitory factor, have shown utility in systemic inflammatory conditions (Guleria et al., 2019; Muramaki et al., 2006), underscoring the potential of macrophage-related soluble receptors as biomarkers. However, sCD206’s specific dynamics in AH, including correlations with disease severity, treatment response, and prognosis, have yet to be robustly characterized.
Caveats and uncertainty
Current evidence for sCD206 as a biomarker in alcoholic hepatitis is largely indirect or extrapolated from other diseases. No large-scale, prospective studies have validated sCD206’s diagnostic or prognostic performance in AH. The specificity of sCD206 for macrophage activation in alcoholic hepatitis versus other inflammatory or infectious conditions is unclear, raising concerns about potential confounding.
Serum levels of sCD206 may be influenced by factors such as concurrent infections, systemic inflammation, or liver fibrosis stage, complicating interpretation. The optimal assay methodology, reference ranges, and timing of measurement relative to disease course remain undefined.
Furthermore, the incremental value of sCD206 beyond established clinical and laboratory parameters, including established macrophage markers like soluble CD163, is unknown. The lack of standardized cutoffs and prospective validation limits immediate clinical applicability.
How this may change practice
If validated, serum sCD206 could become a useful adjunct biomarker for monitoring macrophage-driven inflammation in alcoholic hepatitis. It might help identify patients at higher risk of progression or poor outcomes, guide therapeutic decisions, and serve as a surrogate endpoint in clinical trials of anti-inflammatory or antifibrotic agents.
Routine measurement of sCD206 could complement existing clinical scores and liver function tests to refine risk stratification. However, until further validation, clinicians should interpret sCD206 results cautiously and within the broader clinical context.
Future research should focus on longitudinal studies assessing sCD206 kinetics during AH treatment, its correlation with histological and clinical endpoints, and comparison with other macrophage activation markers. Integration with multi-omics approaches may also clarify its mechanistic role.