Early monitoring of the human polyomavirus BK replication and sequencing analysis in a cohort of adult kidney transplant patients treated with basiliximab.

Background: Nowadays, better immunosuppressors have decreased the rates of acute rejection in kidney transplantation, but have also led to the emergence of BKV-associated nephropathy (BKVAN). Therefore, we prospectively investigated BKV load in plasma and urine samples in a cohort of kidney transplants, receiving basiliximab combined with a mycophenolate mofetil-based triple immunotherapy, to evaluate the difference between BKV replication during the first 3 months post-transplantation, characterized by the non-depleting action of basiliximab, versus the second 3 months, in which the maintenance therapy acts alone. We also performed sequencing analysis to assess whether a particular BKV subtype/subgroup or transcriptional control region (TCR) variants were present.

Polyomavirus JC reactivation and noncoding control region sequence analysis in pediatric Crohn's disease patients treated with infliximab.

The recent introduction of monoclonal antibodies in Crohn's disease (CD) management has been associated with the development of serious complications, such as the progressive multifocal leukoencephalopathy (PML), caused by JC polyomavirus (JCV) reactivation. Therefore, the aims of our study have been the investigation of the possible JCV reactivation in pediatric CD patients treated or not with infliximab, performing quantitative PCR in urine, plasma, and intestinal biopsies at the time of recruitment (t0) and every 4 months in 1 year of follow-up (t1, t2, and t3), and the analysis of the JCV noncoding control region (NCCR) to detect cellular transcription factors binding site mutations. Results obtained showed that, in urine and ileal specimens, JCV load significantly increased in infliximab-treated patients after 1 year of treatment (t3), while viremia was significantly higher at t1.

Early years of biological agents therapy in Crohn's disease and risk of the human polyomavirus JC reactivation.

Although the remarkable efficacy of biological therapy has resulted in significant success in inflammatory bowel disease (IBD) management, susceptibility to infections remains a concern. The biological agents include the tumor necrosis factor-alpha (TNF-alpha) inhibitors, for instance infliximab, and other immunomodulating agents, such as natalizumab. Progressive multifocal leukoencephalopathy (PML), a rare but mostly fatal opportunistic brain infection caused by reactivation of the human polyomavirus JC virus (JCV), has been found in two patients with multiple sclerosis and one patient with Crohn's disease (CD), linked to treatment with natalizumab.