Accession Number : ADA334081

Title :   Novel Gene Therapy for Enhancing Anti-Tumor Immunity.

Descriptive Note : Annual rept. 1 Jul 96-30 Jun 97,

Corporate Author : MARYLAND UNIV BALTIMORE

Personal Author(s) : Baskar, Sivasubramanian

PDF Url : ADA334081

Report Date : JUL 1997

Pagination or Media Count : 35

Abstract : The major goal of this project is to constitutively express syngeneic MHC class II molecules (I-Ad), the T cell costimulatory molecules (B7-l, B7-2) or both on murine mammary carcinoma tumor cell lines (410.4 and 66.1) and investigate their ability to induce anti-tumor immunity in the host. Transfectants of both tumor cell lines expressing I-A(d) molecules showed significantly slower growth in naive Balbic mice and formed smaller tumors compared to their wild type counterparts, and in some cases were completely rejected. These transfectants showed unimpaired growth in athymic nude mice. Based on these results, it is suggested that the I-Ad positive tumor cells are able to present tumor antigen(s) to and activate the CD4+ T cells resulting in a moderate tumor immunity in the naive immunocompetant host. Administration of murine recombinant IL- 12 while reduced the growth of wild type tumor cells, completely abolished the growth of B7-1 transfectants and prevented metastasis. Multiple injections of irradiated I-Ad positive tumor cells induced protective immunity indicating the possible combination of direct and indirect (cross priming) antigen presentation to the tumor-specific T cells. Using the transfectants coexpressing both I-Ad and B7-1 molecules, the therapeutic value of gene-modified tumor cell vaccine will be investigated.

Descriptors :   *GENES, *T LYMPHOCYTES, *IMMUNITY, *CELLS(BIOLOGY), *ANTIGENS, INJECTION, MOLECULES, NEOPLASMS, THERAPY, MICE, WILDLIFE, METASTASIS.

Subject Categories : Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE