HTLV1-Associated Myelopathy Tropical Spastic Paraparesis Mechanism from System Virology Approach

Human T-cell leukaemia virus type I (HTLV-I) is retrovirus type C which has been identified since 30 years ago from cutaneous T-cell lymphoma (by Poiesz et al) as the first human retrovirus [1]. Given that literatures, approximately 10-20 million people have been infected with HTLV-1 which most HTLV-1- infected individuals are living in endemic countries including Japan, Caribbean, South America, Africa, Australia and Northeast of Iran (specially Mashhad, Neyshabour and Sabzevar). HTLV-1 is transmitted throughout unsafe-sexual contact, blood transfusion, drug injection and breastfeeding [2-3]. HTLV-1 can cause adult T-leukemia (ATL), HTLV1- associated myelopathy tropical spastic paraparesis (HAM/TSP), arthritis, uveitis, infective dermatitis and lymphadenitis or Sjogren syndrome [3]. Although 90% of HTLV-1 infected individuals remain as asymptomatic carriers during their lives; 3- 0.25–4% of HTLV-1 infected persons develop HAM/TSP but accurate mechanism of HAM/TSP remains unknown