KL-6 as a Biomarker of COVID-19 Severity and Prognosis

SARS-CoV-2 virus

Introduction to KL-6

Krebs von den Lungen 6 (KL-6) is a sialylated carbohydrate antigen that was detected by Kohno et al. in 1985. It is a high molecular weight glycoprotein that is expressed by type II alveolar epithelial cells and is a mucin which belongs to MUC-1 in cluster 9.

KL-6 has been investigated as an important pulmonary biomarker that is directly associated with the pathogenic process of interstitial lung disease (ILD), reflecting the extent of damage and regeneration of type II pneumocytes.

Biomarker Role in COVID-19

In a 2021 study by Deng, Kai et al., “Prognostic roles of KL-6 in disease severity and lung injury in COVID-19 patients: A longitudinal retrospective analysis”, the potential role of KL-6 as a COVID-19 biomarker was examined.

KL-6 serum levels were compared between patients with severe COVID-19 cases, mild COVID-19 cases, and healthy controls. The study found that:

  • Serum KL-6 was substantially elevated in severe/critical COVID-19 patients.
Serum KL-6 was substantially elevated in severe/critical COVID-19 patients
  • Early serum KL-6 predicted the prognosis of lung injury of discharged COVID-19 patients.
  • Late serum KL-6 was associated with computed tomography lung lesions areas.
  • Elevated serum KL-6 was correlated to coagulation dysfunctions.
  • Elevated serum KL-6 was correlated to T cells subsets dysfunctions.

In summary, the study results support KL-6 as a biomarker of COVID-19 severity, and also a predictor of the prognosis of lung injury of discharged patients.

Source

This content has been adapted from the paper below. Follow the link to learn more:

Deng, Kai et al. “Prognostic roles of KL-6 in disease severity and lung injury in COVID-19 patients: A longitudinal retrospective analysis.” Journal of medical virology vol. 93,4 (2021): 2505-2512. doi:10.1002/jmv.26793

Product Spotlight

Nanopia KL-6 Assay

Ilex Life Sciences proudly offers the ideal solution for automated serum/plasma KL-6 measurement:

Nanopia® KL-6 Assay

The Nanopia® KL-6 Assay, developed and manufactured in Japan by Sekisui Medical Co., Ltd., is a latex agglutination immunoturbidimetric assay for the quantitative measurement of sialylated carbohydrate antigen (KL-6) concentration in serum or plasma.

KL-6 Synonyms

Krebs von den Lungen 6, Sialylated Carbohydrate Antigen, Mucin-1, Mucin 1, MUC-1, MUC1, 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, CD227.