title: Spontaneous T-cell-rich B-cell lymphoma in a cynomolgus monkey (Macaca fascicularis).
abstract: A spontaneous T-cell-rich B-cell lymphoma (TCRBCL) occurred as a subcutaneous mass in the buccal region and enlarged submandibular lymph node in a 6-year-old female cynomolgus monkey (Macaca fascicularis). The constituent cells were examined by histology, immunohistochemistry and the double labeled-immunofluorescence method (dl-IF). Further, in situ hybridization (ISH) was employed to detect the gene expression of Epstein Barr virus (EBV). Histologically, the mass was comprised mainly of neoplastic large lymphoid cells and reactive small mononuclear cells. Immunohistochemically, the neoplastic large lymphoid cells were positive for CD20, CD79 alpha, MHC class II, and either IgG, IgM, or IgA. Polyclonal Ig production by the neoplastic large lymphoid cells was demonstrated by dl-IF, although IgG-positive ones predominated in number. On the other hand, most of the small mononuclear cells were positive for CD3 and were regarded as reactive T lymphocytes, while the remaining cells appeared to be histocytes or reactive B-cells. Transcripts of EBV gene were not demonstrated in these neoplastic or reactive cells by ISH. This is the first reported case of spontaneous TCRBCL in the cynomolgus monkey.
authors.affiliation: Department of Veterinary Pathology, Nippon Veterinary Animal and Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Michishita
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Nakamura
authors.forename: Ippei
authors.initials: I
authors.lastname: Sakakibara
authors.forename: Fumiko
authors.initials: F
authors.lastname: Ono
authors.forename: Kouji
authors.initials: K
authors.lastname: Fujimoto
authors.forename: Kazusaku
authors.initials: K
authors.lastname: Kamiya
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ishii
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Hayashi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yoshikawa
authors.forename: Kimimasa
authors.initials: K
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D002610:Cheek; D005260:Female; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000276:immunology / Q000473:pathology* / Q000662:veterinary*; D008252:Macaca fascicularis; D008992:Monkey Diseases / Q000276:immunology / Q000473:pathology*; D013601:T-Lymphocytes / Q000473:pathology*