Successful preparation and specificity studies of monoclonal antibodies against lung adenocarcinoma

37

intestine, and heart, but reactive with stomach cancer, breast cancer, and normal skin.

Enzyme treatment study showed the epi- tope recognized was polypeptide. SDS-PAGE and immunoblot analyses suggested the mo- lecular weight of the antigen was 34000.

This antibody may be useful in consi- dering the lineage patterns of human lung cancers.

Successful Preparation and Specificity Studies of Monoclonal Antibodies Against

Lung Adenocarcinoma. Wu, S.F., Ye, Q.W., Dai, H.M., Fang, J., Wang*, Ge*, X.R. Shanghai Chest Hospital and Shanghai Institute of Cell Biology, Academia Sinica*, China.

Fusion of the murine myeloma line NS-1 with spleen cells from BALB/C mice immu- nized with a human lung adenocarcinoma cell line (SPC-A-I) coated with antibodi- es against normal human lung tissues yiel- ded ten stable hybridoma monoclones that produce monoclonal antibodies which reac- ted by indirect immunofluorescence and Avidin Biotin Complex (ABC) assays with immunizing SPC-A-I cells and its trans- plant tissues of nude mice.

Two monoclonal antibodies, LAC-163 and LAC-210, were characterized by immuno- fluorescence on live cells from various tumor cell lines and by ABD on frozen sec- tions of different tumor tissues from sur- gical specimens, and of normal fetal or adult lung and other tissues.

The results obtained indicate that LAC- 163 and LAC-210 reacted and squamous cell carcinoma in both tissue and cell lines, but hardly showed cross-reaction with small cell lung carcinoma and other carcinoma of breast, stomach, colon, rectum, esopha- gus, maxillopalatine and thymoma as well as fetal and adult normal tissues. Those monoclonal antibodies also failed to re- act with various tumor cell lines of ton- gue, breast, malignant mesothelioma and

hepatoma.

Serological and Innnunohi~tochemical Stu- dies on Sialylated Lewis Antigen in Sera and Tissues from Lung Cancer Patients. Sugawara, Y., Nat~ri, H., Asakaw~, M., Su- zuki, A,, Yoshida ,,~., Kusajima** K., Komatsu **S., Iguro , T., Iwaki , Y., Terasaki , P.I. Dept. Med./Section 3. *Dept. Surg./Section 2. Sapporo Medical College, Sapporo, Japan. ** Dept. Surg. UCLA School of Med., University of Cali- fornia, Los Angeles, U.S.A.

In recent years numerous monoclonal antibodies against tumor-associated an- ticens have been identified. High titers of reverse passive hemagglutination (RPHA)

were noted in sera from lung cancer pa-

tients with a new monoclonal IgM antibody CSLEXI x

that can detect the sianylated Lewis antigen. Immunohistochemical studies of the sialylated

Lewis x antigen were carried out to determine the histological localization of this antigen in lung can- cer tissues, ee~ xe.~ with CSLU/ (128 ¢..e. o f fun B cancer)

T l t e r o f ~ l i t i v e sera Type ~ . N o . / ( + ) 32x-128x 2 5 6 x -

~ e n o c a r c i n o u 56 2b 18 8 Squa~us c e l l ca. 52 10 9 1 S u l l c e l l ca. 14 4 3 1 ~ r g e c e l l ca . 3 2 1 1 U n d i f f e r e n t l n ~ e d ca. 3 _- 1 1

In the immunohistochemical studies, the posi- tive rates were 70% (22/32) in adenocarcinoma and 15% (2/14) in squamous cell carcinoma. Two out of 6 preoperative sera from immunohistochemically positive adenocarcinoma patients, showed a posi- tive serological reaction. One serologically & immunohistochemically positive case, and five sero- logically & immunohistochemically negative cases were found among 6 cases of squamous cell carci-

noma. Serological and immunohistochemical analysis

suggested the sialylated Lewis x antigen to be a tumor-associated antigen in lung cancer, especi- ally in adenocarcinoma.

Monoclonal Antibodies (MoAbs) to Surface Antigens of Sm~ll Cell Lung Carcinoma (SCLC). I Reeye , J.G., Wulfrank , D.A., Stewart , J., Blee- hen-, N.M.i. MRC Clinical Oncology and Radiothe- rapeutics Unit, MRC Centre, Cambridge, U.K. 2. Department of Radiotherapy, University Hospital, Ghent, Belgium.

Intact SCLC cells from the lines NCI-H69 and the recently derived COR-L32 have been used to produce a panel of MoAbs directed against lung tumour cell surface antigens. These MoAbs were tested in radiobinding assays against 9 pulmona- ry, 6 non-pulmonary, 6 neuroectodermal and i0 o- ther human tumour cell lines. These analyses re- vealed that (a) lung tumour antigens can be divi- ded into those that are restricted to SCLC and those which are common to SCLC and non-small cell lung cancer; (b) while many ttunour cell lines fail to express the antigens, human melanoma and neuro- blastoma lines frequently did express certain SCLC antigens. Immunohistochemical assays revea- led that certain SCLC lung tumour antigens are expressed on brain, normal respiratory epithelium, proximal tubules of adult kidney and neuroendo- crine cells of the adrenal medulla, pancreas and colon.

The biological effect of these MoAbs on SCLC colony growth in vitro was determined using a semi solid agar growth assay. Compared to cells treated with an irrelevant MoAb, complete colony growth inhibition was obtained for SCLC cell lines FRE and POC with the anti-SCLC MoAbs studies, at culture supernatant dilutions of up to 1:40. The growth of HeLa (cervical carcinoma) cells and T278 (osteogenic sarcoma) cells was unaffected by the MoAbs even after treatment with undiluted superna- tants. The anti-proliferative effect of these MoAbs therefore appears to be dependent upon specific antigen binding and may indicate a therapeutic