• human T-cell lymphotrophic virus type 1;
  • adult T-cell leukemia;
  • Sjögren's syndrome;
  • exocrine gland;
  • salivary gland

Abstract: Objectives: We describe a rare case of adult T-cell leukemia (ATL) presenting with dry mouth and swelling of bilateral parotid and submandibular glands. The unusual involvement of these exocrine glands by malignant cells prompted us to conduct a detail characterization of these infiltrating and circulating leukemic T cells, which may provide insight to the pathogenesis of exocrine involvement in ATL. Methods: Immunophenotyping of peripheral ATL cells and microscopic examinations of various organs prepared by autopsy were performed. Analysis of the repertoire of T-cell receptor (TCR) of parotid gland-infiltrating ATL cells using molecular and immunohistochemical examinations were also performed. Results: Microscopic examinations of various organs prepared by autopsy revealed the predominant and specific exocrine gland infiltration of ATL cells. Reverse transcription-polymerase chain reaction (RT-PCR) followed by both TCR spectratyping and complementary determining region (CDR)-3 sequencing analysis of TCR Vβ of parotid gland-infiltrating T cells revealed a relatively restricted but not single usage of TCR Vβ. Immunohistochemical analyses of parotid gland specimens detected only a small number of TCR Vαβ-positive cells in parotid gland-infiltrating ATL cells. Conclusions: The predominant infiltration of ATL cells in exocrine glands implied that these T cells recognized exocrine gland-specific antigen. However, the absence of both TCR Vβ mRNA transcripts and TCR Vαβ protein expression in most ATL cells suggested that antigen recognition via TCR may not have played a major role in adhesion and subsequent infiltration into the exocrine glands in this patient. These results provide important background information to further elucidate the pathogenesis of exocrine gland-specific inflammation.