Open Access Research article

APRIL, a proliferation-inducing ligand, as a potential marker of lupus nephritis

Worapot Treamtrakanpon1, Pornpen Tantivitayakul26, Thitima Benjachat25, Poorichaya Somparn2, Wipawee Kittikowit3, Somchai Eiam-ong1, Asada Leelahavanichkul4, Nattiya Hirankarn24 and Yingyos Avihingsanon12*

Author affiliations

1 Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok, Thailand, 10330

2 Lupus Research Unit, Department of Medicine, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok, Thailand, 10330

3 Department of Pathology, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok, Thailand, 10330

4 Department of Microbiology; Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok, Thailand, 10330

5 Biomedical Science, Interdisciplinary Program, Graduate School, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok, Thailand, 10330

6 Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, 6 Yothe Road, Rajthevee, Bangkok, Thailand, 10400

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Citation and License

Arthritis Research & Therapy 2012, 14:R252  doi:10.1186/ar4095

Published: 21 November 2012

Abstract

Introduction

BLyS and APRIL are cytokines from the tumor necrosis factor family which play an important role in systemic lupus erythematosus (SLE). Previous works suggested an association between both molecules and SLE disease activity although their correlation with lupus nephritis is not known. We therefore assessed serum BLyS and APRIL in active lupus nephritis patients.

Methods

Serum samples from active lupus nephritis and at 6 months post-treatment were obtained. Serum levels of BLyS and APRIL (n = 47) as well as renal mRNA expression were measured. Serum levels of both molecules and clinical data (n = 27) were available at 6 months follow-up. All biopsy-proven lupus nephritis patients were treated with similar immunosuppressive drugs.

Results

Serum levels of APRIL were associated with proteinuria (Rs = 0.44, P value < 0.01) and degree of histological activity (Rs = 0.34; P value < 0.05) whereas BLyS levels were associated with complement levels (Rs = 0.46; P value < 0.01) and dosage of immunosuppressant. Interestingly, serum APRIL as well as its intrarenal mRNA levels were associated with resistance to treatment. From the receiver operating characteristic (ROC) analysis, high levels (> 4 ng/mL) of serum APRIL predicted treatment failure with a positive predictive value of 93 percent.

Conclusion

APRIL could be a potential biomarker for predicting difficult-to-treat cases of lupus nephritis.