A Monoclonal Antibody (Po66-2) Reactive with Human Lung Squamous Cell Carcinoma — Cell Reactivity In Vitro and Preliminary Scintigraphic Trials

Abstract

Lung squamous cell carcinomas (LSqCC) represent about 40% of lung cancers. Surgical extirpation is the primary mode of curative therapy; radiation and chemotherapy can be used as palliative therapy but their success remains uncertain. Seventy per cent of patients die within five years following diagnosis (Yabio et al., 1983). Monoclonal antibodies (MA) against LSqCC have been produced by various techniques generally using mouse plasmacytomas hybridized with mouse lymphocytes immunized against culture cell lines of human tumors, a technique used for the preparation of most anti-carcinoma MA (Kasai et al., 1981). In the present work, however, the establishment of cell lines was thought to lead possibly to the selection of cells with a high dividing potential and a poor expression of differentiation antigens. For the preparation of MA Po66, we therefore preferred to take uncultured cells from fresh cancerous tissue. The tissue specificity of the MA and its ability to immunolocalize subcutaneous xenografts in nude mice were investigated. Trials to localize tumors by scintigraphy in patients with LSqCC were also performed. The tumors were visualized 2 to 11 days after i.v. infusion of I-131 labeled-Po66. Comparisons with other investigations such as CT scan, endoscopy and histological and surgical data were carried out.