Figure 5. Detection and molecular characterization of WU virus isolated from a chronic lymphocytic leukemia patient.

(A) Hematoxylin and eosin (H&E) staining of a lung tissue biopsy sample shows intranuclear inclusion bodies (black arrows). (B) PAb416 staining correlates with H&E staining and shows nuclear staining of the respiratory epithelium (brown). (A and B) Original magnification, ×20. (C) Specific primers for different human polyomaviruses (HPyVs) were tested on rolling circle amplification products. KI virus/WU virus–specific (KIV/WUV-specific) amplification is indicated with a red arrow. BKV, BK virus; JCV, JC virus; MCV, Merkel cell polyomavirus; TSV, trichodysplasia-spinulosa virus; NJPyV, New Jersey polyomavirus. (D) Genome map of the WUV isolate WU_PITT3. The early region encodes for large T (LT) and small T (sT) antigens. The late region comprises viral capsid protein VP1, VP2, and VP3. The noncoding control region (NCCR) contains the putative origin of replication and promoters. (E) Immunohistochemistry staining of WUV with VP1 antibody shows nuclear and cytoplasmic staining of a large number of lumenally located cells of the dysplastic respiratory epithelia (brown). Original magnification, ×10 (left); ×40 (right).