Gamma-delta T Cells in Bladder Cancer Draining Lymph Nodes

Background: Gamma-delta (gamma delta) T cells are a distinct subset of T cells with a receptor composed of gamma and delta chains. Their ability to directly recognize stress-induced molecules and non-peptide antigens expressed by cancer cells, along with their capacity to produce cytokines and interact with other immune cells, makes them potentially significant contributors to immune-based treatments. Objective: To investigate the presence and frequency of T gamma delta cells in tumor-draining lymph nodes of patients with bladder cancer (BC), and to assess their association with prognostic parameters. Methods: Forty-nine fresh tumor-draining lymph nodes from untreated patients with BC were minced to obtain single cells. The cells were surface-stained with anti-CD3, anti-TCR gamma delta, and antiHLA-DR antibodies, then acquired on a four-color FACSCalibur flow cytometer, and analyzed by FlowJo software. Results: On average, 2.07%+/- 1.99% of CD3+ lymphocytes in regional nodes of BC exhibited a gamma delta T phenotype. A considerable percentage of these cells (37.90%+/- 24.42%) expressed HLA-DR. Statistical analysis revealed that while the frequency of gamma delta T cells showed no variation among patients with different prognoses, the HLA-DR+ subset was higher in T4 patients than in T2 patients (p=0.031). These cells also tended to be increased in stage III compared to stage II (p=0.077). Conclusion: The data collectively indicated an association of HLADR expressing gamma delta T cells with prognostic factors related to tumor progression (higher T-group and stage), suggesting their potential involvement in disease progression. However, future research, including longitudinal studies with larger cohorts, needs to validate these findings and elucidate the functional roles of gamma delta T cells in the immune response against BC.