Herpesvirus saimiri transformation may help disclose inherent functional defects of mucosal T lymphocytes in patients with gastric adenocarcinoma

Abstract

To dissect the phenotypic and functional features of mucosal T lymphocytes in patients with gastric adenocarcinoma, we have used the Herpesvirus saimiri transformation procedure to achieve T-cell lines from gastric origin. Once achieved, cell function was assessed by in vitro stimulation with mitogens. CD2-specific monoclonal antibodies (α-CD2), alone or in combination with interleukin (IL)-2, rendered fewer counts in patients (34 408±3965 and 52 157±6473 c.p.m., respectively) than in controls (67 471±11 755 c.p.m., P<0.01 and 77 864±12 545 c.p.m., P<0.05, respectively). Likewise, CD3-based responses were defective in cancer cell lines: α-CD3 (54 794±9269 vs 86 104±10 341 c.p.m., P<0.01), α-CD3+IL-2 (57 789±8590 vs 88855±8516 c.p.m., P<0.01) and α-CD3+α-CD2 (52 130±7559 vs 120 852±16 552 c.p.m., P<0.01). Finally, IL-2 failed to adequately stimulate patient cell lines (39 310±4023 vs 60 945±9463 c.p.m., P<0.05). These results suggest that mucosal T lymphocytes in cancer patients are inherently impaired in their proliferative ability. This may be crucial in the control of tumour growth.