X. Zhao et al., ACCUMULATION OF GAMMA DELTA T-CELLS IN HUMAN DYSGERMINOMA AND SEMINOMA - ROLES IN AUTOLOGOUS TUMOR KILLING AND GRANULOMA-FORMATION/, Immunological investigations, 24(4), 1995, pp. 607-618
The precise biological function of a subset of T cells bearing gamma/d
elta T cell receptor (TCR) remains poorly understood. The present stud
y demonstrated the presence of gamma/delta T cells in tumor-infiltrati
ng lymphocytes (TIL) and peripheral blood lymphocytes (PBL) of human p
atients with dysgerminoma and seminoma when determined by flow cytomet
ry and in situ immunohistochemical staining. TIL contained a high perc
entage of gamma/delta T cells, ranging from 17.3 to 35.1%. gamma/delta
T cells often accumulated within the granulomatous inflammation of tu
mor tissues. The majority of gamma/delta T cells were V gamma 9/V delt
a 2+ cells. Freshly isolated PBL, TIL and purified gamma/delta T cells
showed autologous tumor killing (ATK) activity, which could be inhibi
ted by monoclonal antibodies (mAb) against V delta 2. Furthermore, two
gamma/delta T cell clones established from TIL showed cytotoxicity ag
ainst autologous and allogeneic dysgerminoma, while they had low or no
lytic effects on other cell types including carcinomas of ovary and t
umor cell lines such as K562, Daudi and Molt-4. Lysis of autologous tu
mor cells by the clone was inhibited completely by anti-V delta 2 mAb
and partially by mAb against CD3, LFA-1 alpha and ICAM-1 molecules, wh
ile it was resistant to anti-CD8, anti-HLA-ABC and anti-HLA-DR mAb. Su
pernatants produced by gamma/delta T cell clones induced adhesion, agg
regation and increased DNA synthesis of monocytes and some characteris
tics of activated macrophages or epithelioid cells. Tumor necrosis fac
tor (TNF)-alpha, granulocyte-macrophage colony stimulating factor (GM-
CSF) and interferon (IFN)-gamma I were detected in the supernatants of
gamma/delta T cell clone. These results suggest that gamma/delta T ce
lls accumulating in dysgerminoma and seminoma exhibit ATK activity thr
ough V gamma 9/delta 2 TCR and these gamma/delta T cells also play a r
ole in the formation of granulomatous inflammation, which is associate
d with human dysgerminoma and seminoma.