ANTI-RO52 KDa and ANTI-RO60 KDa Analysis in Systemic LUPUS Erythematous Patients to Detect ANTI-RO False-Negatives

Elena Grau Garcia¹, Inmaculada Chalmeta Verdejo¹, David Gimenez-Romero², Eztizen Labrador Sanchez¹, Merixell Fernandez Matilla³, Francisco Miguel Ortiz-Sanjuán¹, Carlos Feced Olmos¹, Nagore Fernandez-Llanio Cornella³, Karla Arevalo Ruales¹, Rosa Negueroles Albuixech¹, Jose Ivorra Cortes¹, Jorge Juan Fragio Gil¹, Isabel Martinez Cordellat¹, Roxana Gonzalez Mazario¹, Luis Gonzalez Puig¹, Cristina Alcañiz Escandell¹, Carmen Najera Herranz¹, Ines Canovas Olmos¹, Elvira Vicens Bernabeu¹, Jose Eloy Oller Rodriguez¹, Jose Antonio Castellano Cuesta³, Victoria Fornes Ferrer⁴, David Hervás Marín⁴, Marta De la Rubia Navarro¹ and Jose Andres Roman Ivorra¹, ¹Rheumatology Department. Hospital Universitario y Politecnico La Fe, Valencia, Spain, ²Physical-Chemistry Department, UV, Valencia, Spain, ³Rheumatology Section. Hospital Arnau de Vilanova, Valencia, Spain, ⁴Biostatistics Unit. IIS La Fe, Valencia, Spain

Meeting: ACR/ARHP Annual Meeting 2017

Date of first publication: September 18, 2017

Keywords: Lupus and autoantibodies

Session Information

Date: Sunday, November 5, 2017

Title: Systemic Lupus Erythematosus – Clinical Aspects and Treatment Poster I: Biomarkers and Outcomes

Session Type: ACR Poster Session A

Session Time: 9:00AM-11:00AM

Background/Purpose:

Systemic lupus erythematous (SLE) is an autoimmune disease characterized by immune system disruption with autoantibodies production. One of the upregulated autoantibodies is the specific to the Ro antigen, a ribonucleoprotein associated to a small RNA, constituted by the 52KDa and 60 KDa polypeptides, whose epitopes are mainly conformational. The routine detection method for anti-Ro is an enzyme immunoassay, however, is possible to obtain false-negatives for anti-Ro and this could be avoided by analyzing both subunits separately. The aim of the present study is to identify false-negatives for anti-Ro by analyzing both 52KDa and 60 KDa subunits separately, as well as to characterize if there are clinical or molecular differences in this subgroup of patients compared to anti-Ro negative cases.

Methods:

A cross-sectional, observational study of patients diagnosed of SLE according to SLICC 2012 criteria was performed. In these patients a complete blood-test was made, and clinical data by personal interview was collected. INF1A, Anti-Ro, anti-Ro52KDa and anti-Ro60KDa levels where measured by colorimetric methods. Biostatistical analysis was performed with R 3.3.2.

Results:

We selected 69 SLE patients with negative results for anti-Ro (2.34±4.17 U/mL) out of 142 total SLE patients. A total of 51 patients were negative for both anti-Ro subunits and 18 cases presented positive results (up to 20 pg/mL) for at least one of them.

	NEGATIVES N=51	Anti-RO52KDa POSITIVES N=8	Anti-RO60KDa POSITIVES N=2	Anti-RO52KDa / Anti-RO60KDa POSITIVES N=8
Anti-RO [U/mL] Mean (DS)	1.92 (3.11)	1.65 (3.2)	0.5 (0.71)	6.15 (8.37)
Anti-RO52 KDa [pg/mL] Mean (DS)	1.26 (1.89)	147.24 (74.25)	1.05 (0.89)	196.82 (50.06)
Anti-RO60 KDa [pg/mL] Mean (DS)	1.73 (2.71)	6.3 (7.01)	120.96 (111.78)	145.22 (76.69)

The subgroup of patients that exhibit simultaneously high levels of anti-Ro52KDa and anti-Ro60KDa have higher clinical activity compared to negative anti-Ro cases (75% of active patients against 41.2% in anti-Ro negative patients). However, no differences in the accumulated damage evaluated by SLICC score between negative anti-Ro cases and patients with at least one positive subunit were observed.

We analyze serum levels of INF1A cytokine in the four groups of patients, and anti-Ro and subunits negative cases showed significant lower INF1A levels than the other patients (8.26±14.87 pg/mL and 26.62±40.71 pg/mL respectively; P=0.04). In addition, patients with high levels of anti-Ro52KDa subunit are those with the highest INF1A levels (anti-Ro 52+/anti-Ro60- 23.5±47.6pg/mL of INF1A; anti-Ro 52+/anti-Ro60+ 36.4±37.9pg/mL of INF1A).

Conclusion:

In our anti-Ro seronegative patients, a 26% of false-negative cases were detected. These cases with high levels of almost one anti-Ro subunit showed significantly higher levels of INF1A in contrast to negative cases, supporting the fact that they are indeed a different group from the negative cases. Moreover, the high INF1A levels could be the reason of the observed differences in the clinical activity measured by SLEDAI score in both groups.

Disclosure: E. Grau Garcia, None; I. Chalmeta Verdejo, None; D. Gimenez-Romero, None; E. Labrador Sanchez, None; M. Fernandez Matilla, None; F. M. Ortiz-Sanjuán, None; C. Feced Olmos, None; N. Fernandez-Llanio Cornella, None; K. Arevalo Ruales, None; R. Negueroles Albuixech, None; J. Ivorra Cortes, None; J. J. Fragio Gil, None; I. Martinez Cordellat, None; R. Gonzalez Mazario, None; L. Gonzalez Puig, None; C. Alcañiz Escandell, None; C. Najera Herranz, None; I. Canovas Olmos, None; E. Vicens Bernabeu, None; J. E. Oller Rodriguez, None; J. A. Castellano Cuesta, None; V. Fornes Ferrer, None; D. Hervás Marín, None; M. De la Rubia Navarro, None; J. A. Roman Ivorra, None.

To cite this abstract in AMA style:

Grau Garcia E, Chalmeta Verdejo I, Gimenez-Romero D, Labrador Sanchez E, Fernandez Matilla M, Ortiz-Sanjuán FM, Feced Olmos C, Fernandez-Llanio Cornella N, Arevalo Ruales K, Negueroles Albuixech R, Ivorra Cortes J, Fragio Gil JJ, Martinez Cordellat I, Gonzalez Mazario R, Gonzalez Puig L, Alcañiz Escandell C, Najera Herranz C, Canovas Olmos I, Vicens Bernabeu E, Oller Rodriguez JE, Castellano Cuesta JA, Fornes Ferrer V, Hervás Marín D, De la Rubia Navarro M, Roman Ivorra JA. ANTI-RO52 KDa and ANTI-RO60 KDa Analysis in Systemic LUPUS Erythematous Patients to Detect ANTI-RO False-Negatives [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/anti-ro52-kda-and-anti-ro60-kda-analysis-in-systemic-lupus-erythematous-patients-to-detect-anti-ro-false-negatives/. Accessed .

ACR Meeting Abstracts - https://acrabstracts.org/abstract/anti-ro52-kda-and-anti-ro60-kda-analysis-in-systemic-lupus-erythematous-patients-to-detect-anti-ro-false-negatives/