Murine monoclonal antibody LAM2 defines cell membrane determinant with preferential expression on human lung small‐cell carcinoma and squamous‐cell carcinomas

Abstract

Murine monoclonal antibodies (MAbs) were generated against a human undifferentiated lung carcinoma cell line. The hybridoma designated LAM2 produced an IgM kappa MAb with reactivity to the cell membrane. Indirect immunofluorescence staining and radioimmunoassay showed LAM2 antibody to react preferentially with lung small-cell carcinoma (SCC) cell lines and squamous-cell carcinoma (SQC) cell lines. LAM2 antibody also stained primary cultures of normal bronchial epithelial cells, but was unreactive with human erythrocytes and nucleated marrow cells. Indirect immunofluorescent staining with LAM2 antibody was performed on frozen sections of human tumor tissues and normal tissues. LAM2 antibody stained all 8 SCC carcinomas, 4 of 5 SQC of the lung and head and neck region, and 2 or 4 lung large-cell carcinomas. No staining was seen on lung adenocarcinomas, breast carcinomas, ovarian carcinomas, renal cell carcinomas, colon carcinomas, or mesotheliomas. Staining was present on sections of normal bronchus, but not on normal lung parenchyma, liver, kidney, adrenal or skin. While LAM2 antibody was highly reactive with all SCC examined, its antigenic determinant was not expressed in other cell lines and tumors of presumed neuroectodermal origin, including neuroblastoma, melanoma, and bronchial carcinoid. Radioimmunoprecipitation showed the antigen defined by LAM2 antibody to have two major bands of approximate molecular weights of 45,000 and 125,000. The selective reactivity of LAM2 antibody with SCC and SQC, but not with most other tumor tissues and normal tissues, makes it a good candidate for use in clinical diagnosis and possibly serotherapy.

Immunolocalisation and imaging of small cell cancer xenografts by the IgG2a monoclonal antibody SWA11

“…Our procedure for antibody generation has been previously described (Stahel et al, 1985b at saturating concentration to the plate with SWAl 1 acting as positive control and SWA20 (Workshop cluster 5A) as negative control. Incubation was performed for 1 h at 37°C and then the plates were washed four times with PBS and 1% BSA.…”

Expression of the small cell carcinoma antigens of cluster-5 and cluster-5A in primary lung tumours

“…Antigen expression was independent of the morphological subtype of SCLC. (Stahel et al, 1985), antigens shared with white blood cells (Bunn et al, 1985;Cailland et al, 1984), neuroendocrine antigens (De Leij et al, 1985;Takahashi et al, 1986;Watanabe et al, 1987) and tumour-associated antigens (Waibel et al, 1987;Waibel et al, 1988). In the past, it has been very difficult to evaluate individual antibodies based on the original reports, since different laboratories varied widely on the material and methods used for the description of antibody and antigens.…”

“…This was first shown by Baylin by two-dimensional gel electrophoresis (Baylin et al, 1982) and later by us and others using monoclonal antibody techniques. Cell surface antigens on SCLC identified by monoclonal antibodies can be grouped according to reported tissue reactivities into epithelial antigens (Stahel et al, 1985), antigens shared with white blood cells (Bunn et al, 1985;Cailland et al, 1984), neuroendocrine antigens (De Leij et al, 1985;Takahashi et al, 1986;Watanabe et al, 1987) and tumour-associated antigens (Waibel et al, 1987;Waibel et al, 1988). In the past, it has been very difficult to evaluate individual antibodies based on the original reports, since different laboratories varied widely on the material and methods used for the description of antibody and antigens.…”

Intrapleural Chemo- and Hyperthermotherapies for Malignant Pleural Effusion: A Randomized Prospective Study

“…As shown in Table 1, there were no significant differences between the two treatment groups in terms of age, gender, systemic chemotherapy regimens, stages, or types of primary tumor. [13][14][15][16]. One study reported that intrapleural treatment using a hypotonic cisplatin solution showed a positive response in the control of MPE in patients with SCLC [17].…”