Description
Enzyme immunoassay for the quantitative determination of Krebs von den Lungen-6 (KL-6) in human serum, plasma, or bronchoalveolar lavage fluid (BALF). samples. Quality controls are included with the kit. Developed and manufactured in Europe by PromedeusLab.
Summary
Interstitial lung diseases (ILD) are a group of lung disorders characterized by interstitial lung thickening. Krebs von den Lungen-6 (KL-6) is a 200 kDa glycoprotein that is predominantly expressed by damaged alveolar type II cells, and it has been proposed as a potential biomarker of different ILD. KL-6 has profibrotic and anti-apoptotic effects on lung fibroblasts and reflects the degree and severity of alveolar epithelial injury. KL-6 is predictive biomarker useful in the clinical management of ILD patients, particularly in patients with severe fibrotic lung disorders. Serum KL-6 levels were also found elevated in Rheumatoid Arthritis – Associated ILD patients, and the levels positively correlated with HRCT fibrosis score.
Studies suggest that KL-6 may be a biomarker of COVID-19 severity in patients with SARS-CoV-2 infection, and also a predictor of the prognosis of lung injury of discharged patients.
Other Names
Mucin-1 (MUC-1), Mucin 1 (MUC1), CD227, Krebs von den Lungen-6, Breast carcinoma-associated antigen DF3, Cancer antigen 15-3 (CA 15-3), Carcinoma-associated mucin, Episialin, H23AG, PEMT, Peanut-reactive urinary mucin (PUM), Polymorphic epithelial mucin (PEM), Tumor-associated epithelial membrane antigen (EMA), Tumor-associated mucin, UniProtKB# P15941.
The name KL-6 was originally that of a murine monoclonal antibody reacting with pulmonary adenocarcinoma cell lines and pulmonary epithelial cells. This antibody recognizes a sialylated carbohydrate chain on MUC1.
Principle of Method
The microtiter plate is coated with the antibody specifically binding the KL-6. The human serum, plasma or BALF is incubated in the plate with the capture antibody.
The specimen is washed out and the specifically bound protein is incubated with biotin-labelled detection antibody. Following another washing step, Streptavidin-HRP conjugate is added into the well. Unbound reagent is then washed out. Horseradish peroxidase (HRP) bound in the complex reacts with the chromogenic substrate (TMB) creating the blue colour. The reaction is stopped by addition of STOP solution (H2SO4).
The absorbance values are measured at 450 nm (optionally 450/630 nm) and are proportional to the concentration of KL-6 in the specimen. The concentration of KL-6 in unknown samples is determined from the calibration curve which is created by plotting the absorbance values against the standard concentration values.
Sample Types
Serum, Plasma, Bronchoalveolar Lavage Fluid (BALF)
Typical Standard Curve
Assay Range: 0.156 U/mL - 10 U/mL
Sensitivity
The limit of detection, defined as a concentration of human KL-6 giving absorbance higher than absorbance of blank + 3 standard deviations, is better than 0.04 U/mL of sample.
Precision
Intra-Assay
| Test sample | Mean (U/mL) | SD | CV |
| 1 |
631 |
13.6 |
2.2% |
| 2 |
193 |
3.9 |
2.0% |
Inter-Assay (Run-to-Run)
| Test sample | Mean (U/mL) | SD | CV |
| 1 |
526 |
11.2 |
2.1% |
| 2 |
185 |
3.7 |
2.0% |
Accuracy
Dilution Linearity:
| Test sample | Dilution |
Measured Concentration (U/mL) |
Expected Concentration (U/mL) |
Yield |
| 1 |
629 |
- | - | |
| 1 | 2x | 309 |
314 |
98% |
| 1 | 4x | 155 |
157 |
98% |
| 1 | 8x | 78 |
79 |
100% |
| 2 |
323 |
- |
- | |
| 2 | 2x | 159 |
162 |
99% |
| 2 | 4x | 81 |
81 |
100% |
| 2 | 8x | 44 |
40 |
110% |
Spiking Recovery:
| Test sample | Spike (ng/mL) |
Measured Concentration (U/mL) |
Expected Concentration (U/mL) |
Yield |
| 1 |
- | 195 |
- | - |
| 1 | 500 |
737 |
695 |
106% |
| 1 | 250 |
440 |
445 |
99% |
| 1 | 62.5 |
266 |
257 |
103% |
Storage
The kit must be stored at 2–8 °C. The opened components can be stored for one week at 2–8 °C.
Usage
This assay is for in vitro research use only and is not for use in diagnostic procedures.
Resources
Related Products
Ilex Life Sciences LLC is an authorized distributor of PromedeusLab.