Herpesvirus Saimiri Transformation May Help Disclose Inherent Functional Defects of Mucosal T Lymphocytes in Patients with Gastric Adenocarcinoma

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 (alpha-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: alpha-CD3 (54 794 +/- 9269 vs 86 104 +/- 10 341 c.p.m., P<0.01), alpha-CD3+ IL-2 (57 789 +/- 8590 vs 88855 +/- 8516 c.p.m., P<0.01) and alpha-CD3+ alpha-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.