Soluble CD163 ELISA assay for measuring Macrophage and Monocyte Activation

Intended use

  • This Macro163™ kit is intended for the quantification of soluble CD163 (sCD163) in serum or plasma samples.
  • The Macro163™ assay has been validated for serum and plasma measurements but can also be applied to other biological fluids like synovial fluid, ascites fluid, pleural fluid, cerebrospinal fluid and cell-supernatants.


  • Detection Range: 9 – 30 ng/mL
  • Sensitivity: < 0.23 ng/mL
  • Samples: human serum and plasma
  • Format: sandwich ELISA with polyclonal capture, recombinant sCD163, and a monoclonal detection antibody
  • Manufactured by: IQ Products, The Netherlands
  • Biomarker for macrophage activation and inflammation research
    • Liver diseases – NASH, AIH, cirrhosis
    • Sepsis
    • Rheumatoid arthritis
    • Inflammatory bowel diseases – Celiac disease, ulcerative colitis, Crohn’s disease
    • Diabetes/insulin resistance
    • Macrophage activation syndrome
    • Myeloproliferative diseases (myeloid leukemia, Hodgkin Lymphoma)
    • Systemic sclerosis
    • HIV infection
  • Analyze soluble CD163 levels in serum and plasma
  • Complete ELISA kit
  • Based on the two most published soluble CD163 ELISA protocols
  • Less than 1 hour hands-on time, Results within 4 hours.
  • Use of fully characterized recombinant CD163 protein as standard
  • Standardized and quantitative
  • Only 10ul of sample is needed
  • Ready-to-use pre-coated ELISA plates

The assay is based on the principle of the sandwich ELISA. A polyclonal antibody recognizing CD163 is immobilized on the surface of a microtiter plate.

After incubation with the sample or recombinant CD163 standard a second biotinylated monoclonal antibody recognizing CD163 is added. Detection of the latter is done by adding streptavidin-HRP. Using TMB (3, 3’, 5, 5’-tetramethylbenzidine) as substrate for the enzyme HRP, the amount of sCD163 protein can be quantified.

CD163 is a membrane protein and member of the group B Scavenger Receptor Cysteine-Rich super family specifically expressed on peripheral blood monocytes and macrophages. Macrophages play a central role in the host response to infection and tissue damage, and are furthermore important in the pathogenesis of autoimmune diseases and cancer.

CD163 functions as a scavenger receptor for Haptoglobin-hemoglobin complexes, and furthermore CD163 is involved in the regulation of inflammation. A particularly high expression is seen in macrophages of the ‘alternative activation’ phenotype playing a major role in dampening the inflammatory response and in scavenging components of damaged cells. Soluble plasma CD163 arises from the increased shedding of CD163 mediated by the tumor necrosis factor-α (TNF-α) cleaving enzyme.

Measurement of soluble CD163 (sCD163) may be a valuable marker in researching diseases with macrophage and/or monocyte involvement, such as macrophage activation syndromes (e.g. hemophagocytic syndrome), infections, liver disease (NAFLD/NASH), sepsis, auto-immune disease, chronic inflammatory diseases such as rheumatoid arthritis, atherosclerosis,  and various cancers. Additionally, CD163 positive macrophages constitute a major cell subpopulation in human term placenta suggesting a role for the placenta functioning as an active immunosuppressive biological barrier between mother and fetus.