Detection of tumor antigens by syngeneic antiserum on in vitro, transformed tracheal epithelial cell line 2‐10‐1

Abstract

Sera obtained from rats showing transplantation immunity to syngeneic, malignant epithelial cell line, 2-10-1, were used to identify antigens associated with transformation in vitro. The 2-10-1 cell line was derived from exposure of tracheal explants, in vitro, to the carcinogen MNNG. Tumorigenic passages of the cell line were shown to have common antigenic determinants, shared by independently transformed malignant tracheal epithelial cell lines, as well as antigenic determinants that appear to be limited to the immunizing cell line, 2-10-1. Care was taken to ensure that antibodies were not produced against viral antigens or non-specifically absorbed serum components. Early passages of the 2-10-1 cell line were not tumorigenic in athymic BALB/c (nu/nu) mice, but became malignant with serial passage in vitro. Antigenic specificities recognized by 2-10-1 immune sera were also present on early-passage 2-10-1 cells that had not as yet acquired the malignant phenotype. Such antigen expression must be an early event in neoplastic development.

Monoclonal antibodies directed against rat tracheal epithelial cells transformed in vitro

“…Antibodies with sufficient specificity for identifying cell types that participate in the neoplastic process are potentially useful as markers to study the evolution of neoplastic disease. Previous studies demonstrated that carcinogen-induced respiratory tract carcinomas possess common tumor-rejection antigens and are capable of stimulating both cellular and humoral immune response in syngeneic animals (Jamasbi and Nettesheim, 1977;Jamasbi et al, 1978;Braslawsky et al, 1981Braslawsky et al, , 1982b. Using the polyclonal antibody response, we detected antigens on cell lines derived from DMBAand M"G-exposed F344 rat tracheal epithelial cells at both non-tumorigenic (early) and tumorigenic (late) passage levels (Braslawsky et al, 1982b).…”

“…An indirect radioisotope assay using 1251-labelled rabbit anti-mouse IgG (for detection of mouse-derived MoAb) or 1251-labelled goat anti-rat IgG (for detection of rat-derived MoAb) was used to determine MoAb binding activity for various target cells (Braslawsky et al, 1982b).…”