Generation of monoclonal antibodies against human lung squamous cell caricnoma and adenocarcinoma using mice rendered tolerant to normal human lung

25 Generation of Monoclonal Antibodies Against HI-,an Lung Squamous Cell Caricnoma and Adenocarcino,k~ Using Mice Rendered Tolerant to Normal Human Lung. Hanai, N., Shitara, K., Yoshida, H. Tokyo Research Laboratories, Kyowa Hakko Kogyo Co., Ltd., Machida-shi, Tokyo 194, Japan. Cancer Res. 46: 4438-bJ+43, 1986. Four murine monoclonal antibodies against human lung carcinoma were generated using a novel i,,,unization procedure. BALB/c mice were rendered neonatally tolerant to normal human lung tissues and subsequently inm~inized with human lung tumor tissues. The lower level of antibody-reactivity to the tolerogen was seen in the sera of mice rendered neonatally tolerant as compared with the level of reactivity in the sera of nontolerant mice. The mice which maintained a sufficiently tolerant state were selected for hybridoma production. Two monoclonal antibodies, KM-32 and KM-34, were developed from mice inununized with lung squamous cell carcinoma tissues and two other monoclonal antibodies, KM-52 and KM-93, were developed from mice inm~mized with lung adenocarcinoma tissues. Distribution of antigens detected by the monoclonal antibodies was investigated by enzyme-linked im~mosorbent assay using membrane fractions prepared from a number of tumorous and normal tissues and various hunk~n normal and tumor cell lines. KM-32 recognized a carbohydrate antigen expressed predominantly on lung s~mmous cell carcinoma cells and its carbohydrate structure appeared to be associated with blood group A antigen. KM-93 recognized a sialylated carbohydrate epitope on the antigen expressed on lung adenocarcinoma cells and a few other tumor cells. KM-3~ and KM-52 detected protein or glycoprotein antigens and they showed predominant reactivity to lung squamous cell carcinoma and lung adenocarcinoma~ respectively. KM-32 and KM34 antibodies showed complement-dependent cytotoxicity against a lung tumor cell line. These results suggest that the tolerance technique is useful for efficient screening of murine monoclonal antibodies specific to human tumors. The efficacy of these four monoclonal antibodies in diagnosis and therapy of lung cancer will be the subject of a sequential study. Monoclonal Mouse Antibodies Raised Against Human Lung Carcinoma. Hellstrom, I., Horn, D., Linsley, P. et al.

ONCOGEN, Seattle, WA 98151, U.S.A. Cancer Res. 46: 3917-3953, 1986. We have evaluated approxi~t~tely, I0,000 monoclonal antibodies (MoAb) resulting from 25 hybridizations of spleen cells from mice ~ized with cells from human non-small cell lung carcinoma or fetal lung. The spleen cells were hybridized with NS-I myeloma cells, and the resulting hybridomas were screened for production of MoAb to nonsmall cell lung carcinoma by binding assays with either cell extracts or cells growing in culture, followed by inmnm~ohistology on frozen sections. Fourteen MoAb had relative specificity for non-small cell lung caricnoma versus normal tissues. Three of these MoAb (L3, L6, LI7) also reacted with most carcinomas of the breast and colon, and two MoAb (L20 and L25) reacted with the four samples of small cell lung carcinoma tested. No MoAb defined an antigen of absolute tumor specificity~ and no MoAb reacted substantially more with adenocarcinoma than squamous cell carcinoma of the lung (or vice versa). Five MoAb were IgGl, two were IgG2a, and the remaining seven were IEM. Seven MoAb (L5, L6, LI5, LI7, L20, L22, L23) could bind to the cell surface. Three MoAb (L6, LI5, LIT) defined carbohydrate antigens, and three (L3, L5, LSO) were to protein antigens, while the antigens to which the remaining MoAb are directed have not been identified. Six MoAb could bind to tumor cells in Carnoy-fixed paraffin-embedded sections. An intercellular variability in antigen expression was detected with all 14 MoAb. At least two of the MoAb, L6 and L20, are good candidates for preclinical testing in view of their high level of tumor selectivity, as shown by both inmn~nohistology and binding assays with living cells. Identification of a Novel Serum Protein Secreted by Lung Carcinoma Cells. Linsley, P.S., Horn, D., Marquardt, H. et al. Oncogen, 3005 First Avenue, Seattle, WA 98119, U.S.A. Biochemistry 55: 5978-5986, 1986. The murine anti-h,.nan lung tumor monoclonal antibody L3 recognizes antigens found both in the medium of cultured carcinoma cells and in normal human serum. Sequential inm~inoprecipitation experiments indicate t_hat the L3 antigen is also recognized by a previously described monoclonal antibody directed against a melanomaassociated antigen (Natali, P.G., Wilson,