Abstract: SA-PO927
Plasma Osteopontin Differentiates Active and Inactive Lupus Nephritis and Is Associated with Response to Therapy
Session Information
- Glomerular Diseases: Translational Studies and Biomarkers
November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Zavala Miranda, Fernanda, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico
- Pérez Arias, Abril A., Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico
- Macedo, Sofia E. Márquez, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico
- Pena, Oscar, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico
- Juarez Cuevas, Bernardo, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico
- Morales-Buenrostro, Luis E., Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico
- Mejia-Vilet, Juan M., Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico
Background
New biomarkers are needed to differentiate activity from chronic damage in Lupus nephritis (LN) & to monitor response to treatment. Osteopontin (OPN) is an N-linked glycoprotein with integrin-binding ligands that has been identified as a potential biomarker of activity in systemic lupus erythematosus (SLE).
Methods
This is a diagnostic study with a cross-sectional and a longitudinal phase to describe the course of plasma (pOPN) & urinary OPN (uOPN) in a LN cohort. We recruited 62 patients with biopsy-proven active LN. As disease controls, we included 88 patients with non-renal activity, chronic LN on kidney biopsy, & inactive SLE. To evaluate the diagnostic yield of OPN we built ROC curves from the cross-sectional data. In the longitudinal phase, we included 36 active LN patients with prospective follow-up and plasma/urine samples collected at 3, 6, & 12 months. Response to therapy was evaluated at 6 & 12 months. Linear mixed models were fitted to evaluate the association between pOPN, uOPN, and response to therapy.
Results
Active LN patients had the highest levels of pOPN (81.18 ng/mL, IQR 53.75-169.46). Elevated pOPN levels correlated with SLEDAI-2K activity score (r= 0.51, p<0.001), SLICC/ACR damage index (r=0.24, p=0.003), ISN/RPS class IV LN (r=0.24, p=0.03), histologic activity index (r=0.46, p<0.001) and eGFR <60 mL/min/1.73m2 (r=0.35, p<0.001). There were no differences in uOPN between the groups. pOPN >58 ng/mL had 72% (95%CI 0.60-0.82) sensitivity and 81% (95%CI 0.71-0.88) specificity to differentiate active LN from inactive patients. The course of pOPN in response to therapy was associated with the type of response, with continuous reduction in complete responders and persistent elevation in non-responders. There was no association between uOPN and response to therapy.
Conclusion
Plasma OPN correlates with LN activity, it has a fast reduction within the first 3 months of therapy and is associated with response to therapy.
OPN ROC curves (A) & course of pOPN in response to therapy (B)