TY - JOUR
T1 - Activation of cd8+murine t cells from tumor-draining lymph nodes by phorbol dibutyrate plus calcium ionophore
AU - Tuttle, Todd M.
AU - Inge, Thomas H.
AU - McCrady, Carl M.
AU - Bethke, Kevin P.
AU - Bear, Harry D.
PY - 1992/7
Y1 - 1992/7
N2 - When lymphocytes from the lymph nodes draining the site of a progressively growing MCA-105 sarcoma are stimulated in vitro with autologous tumor and low-dose interleukin-2 (IL-2), they will grow and develop the ability to lyse autologous tumor cells in vitro; these lymphocytes can also eradicate tumor metastases in vivo. Phorbol esters and calcium ionophores activate signal transduction pathways in T cells and mimic the events triggered by antigen binding. We therefore sought to determine whether large numbers of MCA-105 tumor-specific, therapeutically active T cells could be obtained from MCA-105 draining lymph nodes (DLNs) following a brief exposure to phorbol dibutyrate (PDBu) and ionomycin (Io). DLN cells primarily stimulated with autologous tumor, followed by a secondary stimulation with PDBu-Io and cultured in 20 U/ml IL-2, demonstrated marked expansion of cell numbers during 3 weeks in culture, had moderate cytolytic activity [37% at effector: Target ratio (E:T) = 80:1], and were all CD8+T cells. In contrast, DLN cells stimulated primarily with PDBu-Io and cultured in 20 U/ml IL-2 demonstrated at least 8–10-fold greater growth than antigen-stimulated DLN cells during 3 weeks, were moderately cytolytic (31% at E:T = 80:1), and were a mixed population of CD8+and CD4+T lymphocytes. DLN cells that were expanded by either protocol, like cells stimulated repeatedly in vitro with tumor cells, could eliminate MCA-105 pulmonary metastases when given with IL-2 in an adoptive immunotherapy model. DLN cells stimulated primarily with PDBu-Io completely eradicated MCA-105 metastases but had no in vivo antitumor activity against the syngeneic B16 melanoma or MCA-203 sarcoma. Moreover, pharmacologically activated DLN cells induced tumor regression without concomitant IL-2 administration. The therapeutic effect was abrogated when CD8+T cells were depleted in vivo. Although lymphocytes obtained from the spleens and lymph nodes of non-tumor-bearing animals could be expanded to large numbers after activation with PDBu-Io and culture in IL-2, these cells had no in vivo antitumor activity. Therefore, these results indicate that phorbol dibutyrate plus ionomycin may substitute for tumor antigen and stimulate the growth of T cells that are capable of mediating specific tumor regression.
AB - When lymphocytes from the lymph nodes draining the site of a progressively growing MCA-105 sarcoma are stimulated in vitro with autologous tumor and low-dose interleukin-2 (IL-2), they will grow and develop the ability to lyse autologous tumor cells in vitro; these lymphocytes can also eradicate tumor metastases in vivo. Phorbol esters and calcium ionophores activate signal transduction pathways in T cells and mimic the events triggered by antigen binding. We therefore sought to determine whether large numbers of MCA-105 tumor-specific, therapeutically active T cells could be obtained from MCA-105 draining lymph nodes (DLNs) following a brief exposure to phorbol dibutyrate (PDBu) and ionomycin (Io). DLN cells primarily stimulated with autologous tumor, followed by a secondary stimulation with PDBu-Io and cultured in 20 U/ml IL-2, demonstrated marked expansion of cell numbers during 3 weeks in culture, had moderate cytolytic activity [37% at effector: Target ratio (E:T) = 80:1], and were all CD8+T cells. In contrast, DLN cells stimulated primarily with PDBu-Io and cultured in 20 U/ml IL-2 demonstrated at least 8–10-fold greater growth than antigen-stimulated DLN cells during 3 weeks, were moderately cytolytic (31% at E:T = 80:1), and were a mixed population of CD8+and CD4+T lymphocytes. DLN cells that were expanded by either protocol, like cells stimulated repeatedly in vitro with tumor cells, could eliminate MCA-105 pulmonary metastases when given with IL-2 in an adoptive immunotherapy model. DLN cells stimulated primarily with PDBu-Io completely eradicated MCA-105 metastases but had no in vivo antitumor activity against the syngeneic B16 melanoma or MCA-203 sarcoma. Moreover, pharmacologically activated DLN cells induced tumor regression without concomitant IL-2 administration. The therapeutic effect was abrogated when CD8+T cells were depleted in vivo. Although lymphocytes obtained from the spleens and lymph nodes of non-tumor-bearing animals could be expanded to large numbers after activation with PDBu-Io and culture in IL-2, these cells had no in vivo antitumor activity. Therefore, these results indicate that phorbol dibutyrate plus ionomycin may substitute for tumor antigen and stimulate the growth of T cells that are capable of mediating specific tumor regression.
KW - Adoptive immunotherapy
KW - Effector cells.
KW - Phorbol dibutyrate
KW - Protein kinase C
KW - T cell activation
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UR - http://www.scopus.com/inward/citedby.url?scp=0026651802&partnerID=8YFLogxK
U2 - 10.1097/00002371-199207000-00004
DO - 10.1097/00002371-199207000-00004
M3 - Article
C2 - 1386251
AN - SCOPUS:0026651802
SN - 1524-9557
VL - 12
SP - 32
EP - 40
JO - Journal of Biological Response Modifiers
JF - Journal of Biological Response Modifiers
IS - 1
ER -