Table 1.
Overview of clinical applications and key observations of CD163 in autoimmune nephrological and rheumatic diseases (Jude et al. 2013; Zhang et al. 2020; Gong et al. 2021; Moran et al. 2021)
| Disease | Biomarker | Key clinical application | Key observations | Statistical significance |
|---|---|---|---|---|
| LN | usCD163 | Diagnosis of active LN, assessment of response to treatment | Correlation with activity index (not chronicity), decrease after treatment | AUROC 0.89–0.998 |
| IgAN | usCD163 | Stratification of the risk of events related to kidney disease progression | It correlates with the infiltration of CD163-positive macrophages in the tubulointerstitium, but not in the glomeruli | AUROC 0.788 |
| AAV | usCD163 | Diagnosis of active renal vasculitis, ruling out active disease without biopsy | High negative predictive value | AUROC 0.95 |
| RA | sCD163 | Monitoring disease activity in early RA, predicting the progression of radiological changes, potential significance in dose tapering | Correlation with DAS8 in early RA, no correlation in LSRA | Strong correlation with IL-12 and CXCL (r = 0.99, both) in LSRA |
| SpA | sCD163 | Reflects local synovial macrophage activation rather than systemic inflammation | M2-like phenotype in SpA is shaped by local cytokine gradients at the synovial surface | N/A (mainly qualitative/quantitative observations) |
| PMR | sCD163 | Monitoring subclinical disease activity during treatment (indirectly from GCA studies) | At least 52 weeks of IL-6 pathway inhibition may be needed to reset inflammatory mechanisms | N/A (data mainly from GCA, no studies in isolated PMR) |
| Fibromialgia | Missing | Potential negative discriminator | Negative discriminator between inflammatory and non-inflammatory musculoskeletal pain | Hypothesis for future research |
[i] AAV, ANCA-associated vasculitis; AUROC, area under the receiver operating characteristic; GCA, giant cell arteritis; IgAN, IgA nephropathy; IL, interleukin; LN, lupus nephritis; LSRA, long-standing rheumatoid arthritis; PMR, polymyalgia rheumatic; RA, rheumatoid arthritis; sCD163, soluble CD163; SpA, spondyloarthritis; usCD163, urinary soluble CD163.
Fig 1.
Compartmentalization of clinical information carried by sCD163 in kidney and joint diseases (Matsushita et al. 2002; Baeten et al. 2004; Etzerodt and Moestrup 2013; Mejia-Vilet et al. 2020; Zhang et al. 2020). sCD163, soluble CD163; usCD163, urinary soluble CD163; sfCD163: synovial fluid sCD163.