Intracutaneous Genetic Immunization with Autologous Melanoma-Associated Antigen Pmel17/gp100 Induces T Cell-Mediated Tumor Protection In Vivo

Abstract

Using the differentiation antigen Pmel17/gp100 to genetically immunize C57BL/6 mice (H-2(b)), we and colleagues noticed that only mice that had received the human homolog but not animals injected with the murine counterpart were protected against the growth of syngeneic B16 melanoma cells. The goal of this study was to determine whether the state of nonresponsiveness to the autoantigen Pmel17/gp100 can be broken by immunization with a plasmid DNA construct encoding the autologous form of the molecule. A construct containing the murine form of Pmel17 was administered intradermally to DBA/2 mice (H-2(d)), which were then investigated for the presence of Pmel17/gp100-specific immunity. We show that administration of plasmid DNA coding for the autologous melanoma-associated antigen Pmel17/gp100 protects DBA/2 mice against the growth of Pmel17-positive M3 melanoma cells but not against Pmel17-negative M3 melanoma cells or unrelated P815 mastocytoma cells. Cell depletion experiments demonstrated that this protective effect is mediated by T lymphocytes. The notion that Pmel17/gp100 represents the biologically relevant target in this system was supported by the observations (i) that recipients of Pmel17/gp100 DNA mount an antigen-specific cytotoxic T lymphocyte response and (ii) that M3 tumors growing in mice immunized with autologous Pmel17/gp100 had lost expression of this melanoma-associated antigen whereas M3 melanomas appearing in control-vector-treated animals were still Pmel17/gp100-positive. These results indicate that intracutaneous genetic immunization with autologous melanoma-associated antigen Pmel17/gp100 encoding plasmid DNA can lead to protection against melanoma cells as a result of the induction of a melanoma-associated antigen-specific and protective T-cell-mediated immune response. J Invest Dermatol 115:1082-1087 2000

Identification and Characterization of pDC-Like Cells in Normal Mouse Skin and Melanomas Treated with Imiquimod

“…Melanoma cells M3 (derived from Cloudman S91 melanoma; H-2 d ) were cultured in Ham's F-10 standard medium as previously described (45). M3 cells (6 ϫ 10 5 /mouse) were then injected intradermally in previously shaved back skin of anesthetized DBA/2 female mice (HaarlanWinkelmann).…”

Antitumor immunopreventive effect in mice induced by DNA vaccine encoding a fusion protein of -fetoprotein and CTLA4

“…DNA-based immunization can induce strong cellular immune responses to a variety of antigens, including tumor antigens, such as antigens associated with malignant melanoma [9][10][11] , ovarian carcinoma [12] , breast cancer [13,14] , smallcell lung cancer [15] , neuroblastoma [16] and prostate carcinoma [17] . Two major obstacles in developing rational strategies in tumor immunotherapy are identification of suitable target tumor antigens and effective process and presentation by professional antigen-presenting cells to induce T cell immunity.…”

IL-12 triggers a programmatic change in dysfunctional myeloid-derived cells within mouse tumors

“…C57BL/6 female Il12rb2 -/-mice were crossed with female C57BL/6 P-TCR Tg mice to generate Il12rb2 -/-P-TCR Tg mice. Tumor lines used for in vivo experiments included B16, an H-2 b+ /gp100 + murine melanoma, and Cloudman S91, an H-2 d+ /gp100 + murine melanoma (56). Both tumor lines were purchased from ATCC and established and maintained as previously described (57).…”