title: Granzyme B immunoreactivity in T/natural killer cell lymphomas.
abstract: Granzyme B is one of the serine proteases expressed in natural killer (NK) cells and activated cytotoxic T-lymphocytes. To evaluate the usefulness of granzyme B immunoreactivity in the diagnosis of T/NK-cell lymphoma, we studied 69 cases of lymphomas occurring in the upper aerodigestive tract by paraffin-section immunohistochemistry using a commercially available monoclonal antibody to granzyme B (GrB-7). All 19 cases of T/NK-cell lymphomas defined by the expression of CD56 (NHK-1) and one or both T-cell markers (polyclonal CD3 and CD45RO) expressed granular cytoplasmic granzyme B immunoreactivity. Two out of 9 cases of T-cell lymphomas showing no CD56 expression demonstrated strong granzyme B immunoreactivity. No tumor cells among 39 cases of B-cell diffuse large cell lymphomas and 2 cases of null cell diffuse large cell lymphomas were immunoreactive for granzyme B, however a few scattered granzyme B-positive reactive small lymphoid cells were consistently observed. Based on its sensitivity in this study as well as its reactivity in routinely processed tissue sections, even without heat-induced epitope retrieval technique, monoclonal antibody to granzyme B (GrB-7) can be applied as a useful marker in the diagnosis of T/NK-cell lymphomas in conjunction with CD56.
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: M S
authors.initials: MS
authors.lastname: Cho
authors.forename: M K
authors.initials: MK
authors.lastname: Lee
authors.forename: W I
authors.initials: WI
authors.lastname: Yang
authors.forename: J H
authors.initials: JH
authors.lastname: Yoon
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D053804:Granzymes; D006801:Humans; D007150:Immunohistochemistry; D007694:Killer Cells, Natural / Q000473:pathology*; D008223:Lymphoma / Q000201:enzymology* / Q000473:pathology*; D016399:Lymphoma, T-Cell / Q000201:enzymology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012697:Serine Endopeptidases / Q000378:metabolism*
chemical_list: C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases