Phenotype, functions and fate of adoptively transferred tumor draining lymphocytes activated ex vivo in mice with an aggressive weakly immunogenic mammary carcinoma

• Published in: BMC immunology Vol. 11; no. 1; p. 54
• Main Authors: Miller, Catriona H T, Graham, Laura, Bear, Harry D
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 04-11-2010; BioMed Central; BMC
• Subjects: Animal experimentation; Animals; Breast cancer; Breast Neoplasms - immunology; Breast Neoplasms - pathology; Breast Neoplasms - therapy; Bryostatins - pharmacology; Cancer; Carcinoma - immunology; Carcinoma - pathology; Carcinoma - therapy; CD8-Positive T-Lymphocytes - drug effects; CD8-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - metabolism; CD8-Positive T-Lymphocytes - pathology; Cell Movement - immunology; Cell Proliferation - drug effects; Colleges & universities; Genetic aspects; Immunogenetics; Immunophenotyping; Immunotherapy, Adoptive; Ionomycin - pharmacology; Kinases; Lymph Nodes - pathology; Lymphocyte Activation - drug effects; Lymphocytes; Lymphocytes, Tumor-Infiltrating - pathology; Mice; Neoplasm Regression, Spontaneous; Neoplasm Transplantation; Phenotype; Physiological aspects; Rodents; T cells; Tumor Escape; Tumors
• ISSN: 1471-2172; 1471-2172
• DOI: 10.1186/1471-2172-11-54

Regression of established tumors can be induced by adoptive immunotherapy with tumor draining lymph node lymphocytes activated with bryostatin and ionomycin. We hypothesized that tumor regression is mediated by a subset of the transferred T lymphocytes, which selectively infiltrate the tumor draining lymph nodes and proliferate in vivo.
Adoptive transfer of B/I activated tumor draining lymphocytes induces regression of advanced 4T1 tumors, and depletion of CD8, but not CD4 T cells, abrogated tumor regression in mice. The predominant mediators of tumor regression are CD8+ and derived from CD62L- T cells. Transferred lymphocytes reached their peak concentration (10.5%) in the spleen 3 days after adoptive transfer and then rapidly declined. Adoptively transferred cells preferentially migrated to and/or proliferated in the tumor draining lymph nodes, peaking at day 5 (10.3%) and remained up to day 28. CFSE-stained cells were seen in tumors, also peaking at day 5 (2.1%). Bryostatin and ionomycin-activated cells proliferated vigorously in vivo, with 10 generations evident in the tumor draining lymph nodes on day 3. CFSE-stained cells found in the tumor draining lymph nodes on day 3 were 30% CD8+, 72% CD4+, 95% CD44+, and 39% CD69+. Pre-treatment of recipient mice with cyclophosphamide dramatically increased the number of interferon-gamma producing cells.
Adoptively transferred CD8+ CD62L(low) T cells are the principal mediators of tumor regression, and host T cells are not required. These cells infiltrate 4T1 tumors, track preferentially to tumor draining lymph nodes, have an activated phenotype, and proliferate in vivo. Cyclophosphamide pre-treatment augments the anti-tumor effect by increasing the proliferation of interferon-gamma producing cells in the adoptive host.