Cytolytic (TIA-1+) Tumor Infiltrating Lymphocytes in B Cell Non-Hodgkin's Lymphomas

Abstract

TIA-1 is a monoclonal antibody (mAb) that identifies cytolytic cells. We studied eleven B cell non-Hodgkin's lymphomas (NHL) of low grade, eleven B cell NHL of intermediate-high grade, and 10 benign lymphoid hyperplasias (BLH) to investigate potential differences in the number of host cytolytic tumor infiltrating lymphocytes (TILs). Frozen sections were immunostained with TIA-1 mAb and the number of immunoreactive cells (TIA-1+) per mm2 of tissue was quantitated within reactive or neoplastic lymphoid follicles or random areas of diffuse NHL. The number of TIA-1+ cells/mm2 was significantly higher in intermediate and high grade B cell NHL than in low grade NHL or BLH with means +/- se of 1377.8 +/- 173, 866.2 +/- 92.3 and 774.1 +/- 76.2, respectively (p < 0.0183 and p < 0.0125). There was no significant difference between BLH and low grade NHL. The increased number of TIA-1+ TILs in B cell NHL of intermediate and high grade suggests the possibility of a host cytolytic immune response versus the tumor. Paradoxically, B cell tumors of worst biological outcome contained more cytolytic TILs. Functional defects of host cytolytic TILs in NHL patients should be investigated in future studies.