Reactivation of human polyomavirus JC in patients affected by psoriasis vulgaris and psoriatic arthritis and treated with biological drugs: Preliminary results

Psoriasis vulgaris (PsV) and psoriatic arthritis (PSA) are inter-related heritable inflammatory skin diseases. Psoriatic lesions develop as a result of abnormal immune responses, hyperproliferation and altered differentiation of keratinocytes, and a notable subset of psoriatic patients develops PsA, characterized by joints inflammation. Recently, biological drugs were introduced to treat these diseases. However, this therapy has already been associated with the development of serious life-threatening infections, such as the reactivation of human polyomavirus JC (JCV), responsible for the progressive multifocal leukoencephalopathy (PML), a lethal demyelinating disease caused by oligodendrocytes lytic infection. Therefore, the aims of our study were the investigation of the possible JCV reactivation in PsV and PsA patients treated with adalimumab, etanercept, and methotrexate, performing quantitative real-time PCR in sera and skin biopsies at the time of recruitment (T0) and after 3 (T3) and 6 (T6) months of treatment, and the sequencing analysis of the JCV non-coding control region (NCCR). We found JCV DNA in 5/15 PsV patients and in 2/15 PsA patients and JCV NCCR sequence analysis always showed a structure similar to non-pathogenic CY archetype, with random occurrence of a few irrelevant point mutations. Nevertheless the poor number of patients analyzed, our preliminary data can pave the way for taking into account that the follow-up of JCV DNA detection and the JCV NCCR sequence analysis in psoriatic patients may be important to evaluate the risk of PML onset, considering that patients affected by autoimmune diseases and treated with biologics continue to rise. J. Cell. Physiol. 227: 37963802, 2012. (c) 2012 Wiley Periodicals, Inc.