J Korean Med Sci.  1992 Jun;7(2):128-135. 10.3346/jkms.1992.7.2.128.

Thermo-stability and antitumor activity on colon cancer cell lines of monoclonal anti-CEA antibody-saporin immunotoxin

• Manosroi J
• Kleist SV
• Manosroi A
• Grunert F

• KMID: 1421902
• DOI: http://doi.org/10.3346/jkms.1992.7.2.128

Abstract

Eight saporin peaks were obtained from the purification of seed extracts of Saponaria officinalis L. Saporin peak No. 6 (SAP-6) showed the highest activity in the inhibition of protein synthesis (98%) in an in vitro translation study. An immunotoxin (IT) was prepared from SAP-6 conjugated to a monoclonal anti-CEA antibody 26/5/1 (mab B) using N-succinimidyl pyridyl dithiopropionate (SPDP) and 2-iminothiolane as a cross linker. Under thermal stability study by a DSC (differential scanning calorimetry), the IT showed a denature temperature of 75 degrees C. In in vitro translation studies, the purified IT showed the same activity as SAP-6 at 10(-7) M and 10(-9) M protein concentration at 0, 30 and 60-min incubation effects with mab B and SAP-6 not conjugated at 24-hr incubation periods on human promyelocytic cell line HL 60 and on human colon adenocarcinoma cell lines which were SW 403, LoVo and LS 174 T. SAP-6, mab B and IT had no cytotoxic effect on HL-60. The IT showed a higher cytotoxic effect than SAP-6 in CEA-positive cell lines. The IT demonstrated the highest cytotoxic effect of 51% inhibition of control at 10(-7) M on the LS 174 T.

Keyword

Saporin; Monoclonal anti-CEA antibody; Immunotoxin; DSC; Colon cancer

MeSH Terms

Antibodies, Monoclonal/*therapeutic use
Antineoplastic Agents, Phytogenic/administration & dosage/*pharmacology
Carcinoembryonic Antigen/biosynthesis/*immunology
Colonic Neoplasms/*pathology/therapy
Hot Temperature
Humans
Immunotoxins/*therapeutic use
*N-Glycosyl Hydrolases
Plant Proteins/administration & dosage/*pharmacology
Ribosome Inactivating Proteins, Type 1
Tumor Cells, Cultured/drug effects
Antibodies, Monoclonal
Antineoplastic Agents, Phytogenic
Carcinoembryonic Antigen
Immunotoxins
Plant Proteins
Ribosome Inactivating Proteins, Type 1
N-Glycosyl Hydrolases