Related Experiment Video
Updated: Jan 31, 2026

Dermoscopy Aids in the Diagnosis of Discoid Lupus Erythematosus
Published on: May 16, 2025
Plasma sMer, sAxl and GAS6 levels correlate with disease activity and severity in lupus nephritis
Siwen Gong1, Zhaozhen Xu2, Yang Liu1
1Department of Nephrology, First Affiliated Hospital of Harbin Medical University, Harbin, China.
Objective:
The purpose of this study is to determine whether TAM receptors and ligands associated with the activity and severity of lupus nephritis.
Methods:
Clinical data were statistically analysed and studied in 122 SLE patients, diagnosed from 2013 to 2016 in First Hospital Affiliated to Harbin Medical University. Levels of TAM receptors and ligands in the plasma of 122 SLE patients were measured by ELISA. Renal biopsies were performed to confirm lupus nephritis (LN) by histopathology in 68 patients. The associations of TAM receptors and ligands with clinical and serological parameters were analysed in 68 LN patients.
Results:
Amongst patients with SLE, those with LN had significantly higher plasma sMer, sAxl and GAS6 levels than those without renal involvement (P < 0.01 for all comparisons). Additional comparisons on the renal function-associated clinical parameters confirmed an indicative role of the sMer, sAXL and GAS6 levels in the cohort of patients with more severe nephritis. Patients with higher sMer, sAXL and GAS6 levels of LN patients tended to suffer from proliferative glomerulonephritis. The sAXL and GAS6 levels had a strong positive correlation with activity index (AI) in LN patients. Furthermore, there was a significant drop of the sMer, sAXL and GAS6 concentrations from the time of the biopsy to month t6, but no further decrease from months t6 to t12.
Conclusions:
These results suggest that plasma sMer, sAxl and GAS6 can be an additional clinical marker related to the disease activity and severity in LN.
Related Concept Videos
Correlations
Correlation and Causation
Correlation versus Causation
If the dependent variable increases or decreases when the independent variable increases, there is a positive or negative...
Factors Affecting Renal Clearance: Drug's Physicochemical Properties and Plasma Levels
One important factor is the drug's molecular size. The kidneys readily excrete smaller molecules below 300 Daltons (Da). On the other hand, molecules weighing between 300 and 500 Da are excreted through both urine and bile. Larger molecules above 500 Da tend to be excreted...
Correlation
Two variables, for example, a and b, are said to be positively correlated if both variables move in the same direction. In other words, a positive correlation exists between two variables, a and b, if:
Leveling Effect
High-Level and Low-Level Awareness

