SAT0486 TNF Inhibitors Have No Effects To Human T-Lymphotropic Virus Type-I (HTLV-I)-Infected Cell Line
Authors: S. Fukui, H. Nakamura, Y. Takahashi, H. Hasegawa, K. Yanagihara, T. Nakamura, A. Kawakami
Journal: Annals of the Rheumatic Diseases (2016)

<h3>Background</h3> Biologics are very effective to autoimmune diseases including rheumatoid arthritis and ankylosing spondylitis, but could cause infectious diseases as adverse effects. Human T-lymphotropic virus type-I (HTLV-I) is a retrovirus that infects 10 to 20 million people worldwide (1). The virus is associated with severe diseases, such as adult T-cell leukemia/lymphoma and HTLV-I-associated myelopathy (HAM). It is unknown if HTLV-I proliferates when biologics including TNF inhibitors (TNFi) are used. <h3>Objectives</h3> We evaluated effects of TNFi to HTLV-I infected cells regarding cytokine profiles, TNF receptor (TNFR), mRNA of associated proteins, proviral load (PVL) and apoptosis. <h3>Methods</h3> We used an HTLV-I infected cell line named HCT-5, which is derived from cells in spinal fluid of a patient with HAM. Multiplex cytokine/chemokine bead assays, cytokine levels assessed by enzyme-linked immunosorbent assays (ELISA), fluorescence activated cell sorting (FACS) analysis of TNFR, immunofluorescence staining of GAG, which is a HTLV-1 structural protein, quantitative reverse transcription PCR for Tax (2) and HTLV-I bZIP factor (HBZ) (3), which are needed for immortalization and proliferation of HTLV-I infected cells respectively, HTLV-I PVL (4), and apoptotic ladder detection were performed. We also used Jurkat as a control cell line. <h3>Results</h3> Multiplex cytokine/chemokine bead assays showed supernatants of HCT-5 without any stimuli had time-dependent elevation of IL-6, TNF-alpha, RANTES and ICAM-1. Supernatants of HCT-5 treated with infliximab (IFX), adalimumab (ADA), etanercept (ETN), golimumab (GLM) and certolizumab pegol (CZP) assessed by ELISA showed no differences in levels of these molecules compared to that of HCT-5 with phosphate buffered saline (PBS). In FACS analysis, except for TNFR 2 with ETN, expressions of TNFR 1 and TNFR 2 with each TNFi did not differ from PBS. TNFR 2 declined and internalization of TNFR 2 was detected in HCT-5 with ETN. There was no differences in levels of mRNA of Tax (Figure A, PBGD: house keeping gene) and HBZ (Figure B) with TNFi compared to that with PBS. PVL were also not changed (Figure C, CTR: without any reagents). Immunofluorescence staining of GAG showed no differences between each TNFi and PBS. DNA ladder was not detected in any TNFi and PBS. <h3>Conclusions</h3> <i>In vitro</i>, TNFi did not affect the cytokine profiles, TNFR 1, mRNA of associated proteins, proviral load and apoptosis of HCT-5. Only ETN caused internalization of TNFR 2. <h3>References</h3> de The G, Bomford R. An HTLV-I vaccine: why, how, for whom? AIDS Res Hum Retroviruses. 1993;9:381–6. Harhaj EW, Harhaj NS. Mechanisms of persistent NF-kappaB activation by HTLV-I tax. IUBMB Life. 2005;57:83–91. Matsuoka M, Jeang KT. Human T-cell leukemia virus type 1 (HTLV-1) and leukemic transformation: viral infectivity, Tax, HBZ and therapy. Oncogene. 2011;30:1379–89. Verdonck K, Gonzalez E, Van Dooren S, Vandamme AM, Vanham G, Gotuzzo E. Human T-lymphotropic virus 1: recent knowledge about an ancient infection. Lancet Infect Dis. 2007;7:266–81. <h3>Disclosure of Interest</h3> None declared