Anti-C1q Autoantibodies ELISA Test

Anti-C1q autoantibody ELISA is a specialized laboratory technique used for the quantitative or qualitative measurement of IgG class autoantibodies against the C1q complement factor in human serum or plasma. In clinical practice, this assay serves as a critical biomarker for diagnosing and monitoring Systemic Lupus Erythematosus (SLE), particularly for identifying active Lupus Nephritis (LN).

How it Works (Principle)

• Antigen Coating: Wells of a microplate are coated with purified human C1q.
• Sample Incubation: Patient serum (containing potential anti-C1q antibodies) is added; a high-salt buffer is used to prevent general immune complex interference.
• Washing: Unbound substances are washed away.
• Secondary Antibody: An HRP-labeled anti-human IgG conjugate is added, binding to any captured anti-C1q antibodies.
• Substrate Addition: A colorless substrate (TMB) is added, turning blue where HRP is present.
• Stopping & Reading: A stop solution turns the color yellow, and a microplate reader measures absorbance at 450 nm to quantify antibody levels.

Clinical Significance

• Systemic Lupus Erythematosus (SLE): Strong association with lupus nephritis (kidney inflammation); rising titers often precede kidney flares, and absence predicts a low risk of nephritis.
• Hypocomplementemic Urticarial Vasculitis Syndrome (HUVS): Highly sensitive marker for this condition.
• Monitoring Disease Activity: Helps rheumatologists track disease progression and treatment effectiveness, particularly renal involvement.

Manufacturers

In 2026, several global manufacturers provide anti-C1q autoantibody ELISA kits for both clinical diagnostic (IVD) use and academic research (RUO). These kits are essential for managing systemic lupus erythematosus (SLE) and lupus nephritis.

Major Clinical & Diagnostic Manufacturers

• ORGENTEC Diagnostika (Sebia Group): A leading provider of autoimmune diagnostics. Their Anti-C1q ELISA (ORG 549) and the semi-automated Alegria system are widely used for monitoring lupus nephritis.
• Bühlmann Laboratories AG: Produces the anti-C1q Autoantibodies ELISA, which is highly regarded in clinical literature for its quantitative determination of IgG class autoantibodies.
• DRG International: Offers an Anti-C1q ELISA kit (EIA-5762) specifically designed for the quantitative measurement of IgG autoantibodies in human serum or plasma for professional diagnostic use.
• Inova Diagnostics (Werfen): Marketed under the QUANTA Lite brand, their anti-C1q ELISA is a standard tool in many reference laboratories for SLE evaluation.
• HUMAN (IMTEC): Provides the IMTEC-anti-C1q-antibodies ELISA, which is frequently cited in clinical studies regarding renal involvement in lupus. 

Specialized & Research Kit Suppliers

The following manufacturers provide kits primarily for research applications or specialized laboratory needs:

• Cusabio Technology: Offers the Human Anti-Complement 1q antibody (anti-C1q-antibody) ELISA Kit (Code: CSB-E09165h) for high-sensitivity detection in various sample types.
• Bio-Techne (Novus Biologicals): Supplies Human C1q ELISA kits through its global distribution network, focusing on colorimetric detection for research.
• Abbexa Ltd: Manufactures the Human Anti-Complement C1Q Antibody ELISA Kit with detection ranges suitable for biological fluids like serum and cell culture supernatants.
• Creative Diagnostics: Provides Anti-C1q IgG ELISA kits and custom testing services for complement-related autoantibodies.
• Assay Genie: Offers the Human Anti-C1q Autoantibodies ELISA Kit (SKU: HUFI02269) optimized for human reactivity with high sensitivity. 

Bulk Kit Pricing (Laboratory/Research Use)

Most commercial kits are designed for 96 tests (one microtiter plate). Prices for these kits generally range from $380 to $800 USD per kit.

• Standard Research Kits: Brands like AFG Scientific offer kits starting at approximately $380.
• Mid-Range Kits: Suppliers such as LSBio and MyBioSource typically price their 96-well kits between $465 and $580.
• Premium/Specialized Kits: High-sensitivity kits from Abbexa or Assay Genie are priced between $600 and $715.
• Trial Sizes: Some manufacturers, such as Cusabio, offer a 24-test trial size for approximately $150.