Arthritis & Rheumatism, Volume 63,
November 2011 Abstract Supplement

Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Chicago, Illinois November 4-9, 2011.

Expression of Human Endogenous Retrovirus Herv-K18 In Osteoarthritis Patients.

Fernandez-Gutierrez1,  Benjamin, Garcia-Montojo2,  Marta, Hoyas1,  Jose, Dominguez-Mozo2,  Inmaculada, Villafuertes1,  Esther, Tornero-Esteban1,  Pilar, Arias-Leal2,  Ana

Department of Rheumatology, Hospital Clinico San Carlos, Madrid, Spain
Hospital clinico San Carlos, Madrid, Spain


The etiology of OA remains to be completely understood; however, epidemiological studies have revealed that there are both endogenous and exogenous risk factors for OA. Human endogenous retroviruses (HERV) are assumed to be remnants of ancient exogenous retroviral infections of our ancestors germ-line cells, DNA, resulting in vertical transmission in a Mendelian fashion. HERV sequences constitute approximately 3–8% of the human genome. These include endogenous retrovirus 3 (ERV-3) [4], HERV-W [5], and a number of members of the HERV-K family, suggesting the potential for involvement in autoimmunity [6]. Thus, it has been suggested that ERV-3 may provide a biomarker for osteoarthritis [7]; also, the HERV-K family, that contains some of the most active retroviral elements in the human genome, it has been related with active rheumatoid arthritis [8]. Recently, it has been described a superantigen activity for HERV-K18 [9], and a significantly elevated expression in patients with juvenile rheumatoid arthritis has been found [10].

The purpose of this study was to evaluate the involvement of HERV-K18 in Osteoarthritis (OA), through the analysis of the expression levels in OA patients in comparison with healthy controls, and through the analysis of different qualitative and quantitative clinical variables.


One hundred and thirteen OA patients and 62 controls were included. To analyze HERV-K18 mRNA expression, quantitative RT-PCR was performed; the transcriptional expression was expressed in a relative manner as a normalization ratio (NR), and for controls were assigned a NR=1. The Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC), Lequesne Index, and the Stanford Health Assessment Questionnaire (HAQ) were analyzed in relation to the expression levels of HERV-K18.


We found that 54/113 (47.8%) of OA patients and 22/62 (35.5%) of controls had detectable expression levels of HERV-K18. We found statistical significant differences when we compared the results of the Womac Index, Lequesne Index for knee and hip, and HAQ between OA patients with higher expression (NR>10) vs. OA patients without HERV-K18 expression (p=0.0003, p=0.0005, p=0.002, and p=0.05, respectively), and also when the comparison was made between OA patients with higher expression (NR>10) vs. OA patients with low expression of HERV-K18 (NR=1) for the Womac Index, and Lequesne Index for knee and hip (p=0.002, p=0.013, and p=0.006, respectively).


It seems to be a relation between the health status measurement systems and severity index for OA with the levels of expression of HERV-K18. These results suggest the possible involvement of HERV-K18 in the etiopathogenesis of the disease.

To cite this abstract, please use the following information:
Fernandez-Gutierrez, Benjamin, Garcia-Montojo, Marta, Hoyas, Jose, Dominguez-Mozo, Inmaculada, Villafuertes, Esther, Tornero-Esteban, Pilar, et al; Expression of Human Endogenous Retrovirus Herv-K18 In Osteoarthritis Patients. [abstract]. Arthritis Rheum 2011;63 Suppl 10 :1084

Abstract Supplement

Meeting Menu