EXPANSION OF MUCIN-REACTIVE T-HELPER LYMPHOCYTES FROM PATIENTS WITH COLORECTAL-CANCER

The ability to identify, and expand effector cells with reactivity aga inst tumor-associated antigens (TAA) is critical for effective adoptiv e cellular therapy. The purpose of this study was to assess lymph node lymphocytes sensitized in vivo to the shed TAA TAG-72 as a potential source of cells for adoptive cellular therapy. Lymph nodes containing microscopic tumor and/or shed TAG-72(+) mucin were localized using rad iolabeled CC49 monoclonal antibody and a gamma detector at the time of exploratory colorectal surgery. Lymph nodes containing microscopic tu mor and shed mucin exhibited approximately 40-fold expansion in short- term (<21 days) cultures with either IL-2 or IL-1 plus IL-2; the combi nation of IL-2/anti-CD3 monoclonal antibody (mAb) resulted in signific antly higher expansion. Cultures generated with IL-2 alone favored the expansion of CD8+ and CD56+ cells, whereas addition of IL-I or anti-C D3 mAb to IL-2 promoted outgrowth of CD4+ T-cells. The IL-2/anti-CD3 e xpanded cells exhibited tow levels of cytolytic activity in vitro agai nst autologous and allogeneic colon tumor targets. However, CD4+ cells expanded in IL-2/anti-CD3 retained the ability to proliferate in resp onse to TAG-72 mucin-expressing autologous tumor as well as bovine sub maxillary mucin (BSM) a soluble TAG-72(+) mucin. In addition,CD4+ cell s expressed mRNA for IL-2, IL-4, tumor necrosis factor-beta and IFNg, and retained the ability to secrete IL-2 after expansion. Thus, noncyt olytic, cytokine-secreting, mucin-reactive T- cells can be expanded fr om lymph nodes of patients with colorectal cancer. These cells provide the basis for T-helper adoptive cellular therapy, programs of patient s with advanced colorectal cancer.