BK virus–associated urinary bladder carcinoma in transplant recipients: productive or nonproductive polyomavirus infections in tumor cells?

Nuclear granules are known to mimic virions and are diagnostic pitfalls that have been misinterpreted as viruses in the past [2,3]. [...]based on our assessment and the relatively irregular structure of the illustrated particles in Figure 3, we think Alexiev et al are likely describing "nuclear granules" [3,5,6]. [...]it seems that the molecular studies (all performed on tissue prepared for standard diagnostic workup) do not provide compelling evidence of significant messenger RNA copy numbers for late polyomavirus gene expression, that is, VP1/viral replication.