Hodgkin-like peripheral T-cell lymphoma (PTCL) with preserved Hodgkin-like lesions at autopsy: a case report with an interesting clinical course.

The presence of the so-called Hodgkin and Reed-Sternberg (H-RS) like cells may occur in T-cell non-Hodgkin lymphoma. Reported herein is the autopsy case of Hodgkin-like peripheral T-cell lymphoma (PTCL) in a 77-year-old male with gradual submandibular lymph node enlargement. The first biopsy showed Hodgkin-like PTCL, initially misdiagnosed as classical Hodgkin lymphoma. Although he was treated with a regimen of ABVD, his disease recurred with cervical lymph node enlargement. A second biopsy showed angioimmunoblastic T-cell lymphoma (AITL) and H-RS like cells became obscure. Despite treatment with the CHOP regimen, he died. An autopsy confirmed that only Hodgkin-like lesions preserved while the AITL component had disappeared. This clinical course is very interesting in that only the Hodgkin-like lesions were systematically exacerbated and became the main cause of death. There are no reports of Hodgkin-like PTCL following AITL and finally preserved Hodgkin-like lesions in autopsy.

Identification of ectopic anionic trypsin I in rat lungs potentiating pneumotropic virus infectivity and increased enzyme level after virus infection.

Extracellular cleavage of virus envelope fusion glycoproteins by host cellular proteases is a prerequisite for the infectivity of mammalian and nonpathogenic avian influenza viruses, and Sendai virus. In search of such target processing proteases in the airway, we recently found a new candidate trypsin-like processing protease in rat lungs, which was induced by Sendai virus infection, and identified as ectopic rat anionic trypsin I. On SDS/PAGE under reducing and nonreducing conditions, the purified enzyme gave protein bands corresponding to 29 and 22 kDa, respectively, i.e. at the same positions as rat pancreatic anionic trypsin I. It exhibited an apparent molecular mass of 31 kDa on molecular sieve chromatography and its isoelectric point was pH 4.7. The amino-acid sequences of the N-terminus and proteolytic digest peptides of the purified enzyme were consistent with those of rat pancreatic anionic trypsin I. Its substrate specificities and inhibitor sensitivities were the same as those of the pancreatic enzyme. The purified enzyme efficiently processed the fusion glycoprotein precursor of Sendai virus and hemagglutinin of human influenza A virus, and potentiated the infectivity of Sendai virus in the same dose-dependent manner as the pancreatic one. Immunohistochemical studies revealed that this protease is located in the stromal cells in peri-bronchiolar regions. These results suggest that ectopic anionic trypsin I in rat lungs induced by virus infection may trigger virus spread in rat lungs.