Application of an in Situ PCR hybridization method to detection of human T-lymphotropic virus type I-infected cells in the lung.

We applied an in situ polymerase chain reaction (PCR) hybridization method in order to detect human T-lymphotropic virus type I-infected cells in routinely-processed paraffin sections of the lung from 13 autopsied patients with adult T-cell leukemia (ATL). Previously reported protocol resulted in somewhat non-specific staining in our sections. Therefore, we used a hot start PCR method using specialized commercially-available polymerase in order to increase the specificity. Of 6 patients with ATL cell invasion into the lungs, 4 exhibited strong positive staining of almost all invading ATL cells. In contrast, 7 patients without ATL cell invasion into the lungs did not demonstrate any significant reactivity. Since the method described here is a relatively simple hot start method and does not yield false-positives, it may allow us to determine whether human T-lymphotropic virus type I (HTLV-I) associated disorders are related to lymphocytes integrating the HTLV-I genome.