Carbohydrate-directed conjugation of cobra venom factor to antibody by selective derivatization of the terminal galactose residues

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Cobra venom factor (CVF) can cause cell death by complement-mediated bystander cell lysis. Several studies have investigated CVF for application in cancer therapy by conjugating CVF to antibodies against tumor cell surface-specific antigens via the side-chain amino acid residues. In most cases, the activity of CVF was markedly impaired, presumably by modification of the factor B binding domain due to random derivatization. Since CVF is a glycoprotein and its oligosaccharide chains are distal to the factor B binding domain, coupling of CVF to antibodies through its oligosaccharide chains is expected to yield immunoconjugates with retention of CVF activity and elimination of the immunoreactivity of the terminal α-galactosyl residues. In this study, we investigated the carbohydrate site-directed conjugation of CVF to a monoclonal IgG specific to a cell-surface antigen of human ovarian cancer cells. The terminal galactosyl residues of CVF were selectively modified at C-6 by treatment with galactose oxidase, and the generated aldehyde groups were derivatized in situ with hydrazides containing either protected thiol or maleimide functional groups. The CVF derivatives were allowed to react with thiol groups introduced to the antibody by derivatization with 2-iminothiolane to yield carbohydrate site-directed CVF-antibody conjugates. In both cases, 30-40% of the antibody cross-linked to CVF to yield predominantly monovalent CVF-antibody conjugates. The purified immunoconjugates retained 70-75% of CVF activity and significant level of antigen-binding capacity. This is the first study to exploit the oligosaccharide chains of CVF for the preparation of active immunoconjugates.

Original languageEnglish (US)
Pages (from-to)271-279
Number of pages9
JournalBioconjugate Chemistry
Volume12
Issue number2
DOIs
StatePublished - Apr 5 2001

Fingerprint

Carbohydrates
Galactose
Antibodies
Oligosaccharides
Antigens
Immunoconjugates
Cells
Glycoproteins
Cell death
Aldehydes
Functional groups
cobra venom factor
Amino acids
Tumors
Surface Antigens
Sulfhydryl Compounds
Derivatives
Galactose Oxidase
Neoplasm Antibodies
Ovarian Neoplasms

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Bioengineering
  • Biomedical Engineering
  • Pharmacology
  • Pharmaceutical Science
  • Organic Chemistry

Cite this

@article{0025d394e5a44c23b4108321f9ee5204,
title = "Carbohydrate-directed conjugation of cobra venom factor to antibody by selective derivatization of the terminal galactose residues",
abstract = "Cobra venom factor (CVF) can cause cell death by complement-mediated bystander cell lysis. Several studies have investigated CVF for application in cancer therapy by conjugating CVF to antibodies against tumor cell surface-specific antigens via the side-chain amino acid residues. In most cases, the activity of CVF was markedly impaired, presumably by modification of the factor B binding domain due to random derivatization. Since CVF is a glycoprotein and its oligosaccharide chains are distal to the factor B binding domain, coupling of CVF to antibodies through its oligosaccharide chains is expected to yield immunoconjugates with retention of CVF activity and elimination of the immunoreactivity of the terminal α-galactosyl residues. In this study, we investigated the carbohydrate site-directed conjugation of CVF to a monoclonal IgG specific to a cell-surface antigen of human ovarian cancer cells. The terminal galactosyl residues of CVF were selectively modified at C-6 by treatment with galactose oxidase, and the generated aldehyde groups were derivatized in situ with hydrazides containing either protected thiol or maleimide functional groups. The CVF derivatives were allowed to react with thiol groups introduced to the antibody by derivatization with 2-iminothiolane to yield carbohydrate site-directed CVF-antibody conjugates. In both cases, 30-40{\%} of the antibody cross-linked to CVF to yield predominantly monovalent CVF-antibody conjugates. The purified immunoconjugates retained 70-75{\%} of CVF activity and significant level of antigen-binding capacity. This is the first study to exploit the oligosaccharide chains of CVF for the preparation of active immunoconjugates.",
author = "Q. Fu and Gowda, {D. C.}",
year = "2001",
month = "4",
day = "5",
doi = "10.1021/bc000100u",
language = "English (US)",
volume = "12",
pages = "271--279",
journal = "Bioconjugate Chemistry",
issn = "1043-1802",
publisher = "American Chemical Society",
number = "2",

}

TY - JOUR

T1 - Carbohydrate-directed conjugation of cobra venom factor to antibody by selective derivatization of the terminal galactose residues

AU - Fu, Q.

AU - Gowda, D. C.

PY - 2001/4/5

Y1 - 2001/4/5

N2 - Cobra venom factor (CVF) can cause cell death by complement-mediated bystander cell lysis. Several studies have investigated CVF for application in cancer therapy by conjugating CVF to antibodies against tumor cell surface-specific antigens via the side-chain amino acid residues. In most cases, the activity of CVF was markedly impaired, presumably by modification of the factor B binding domain due to random derivatization. Since CVF is a glycoprotein and its oligosaccharide chains are distal to the factor B binding domain, coupling of CVF to antibodies through its oligosaccharide chains is expected to yield immunoconjugates with retention of CVF activity and elimination of the immunoreactivity of the terminal α-galactosyl residues. In this study, we investigated the carbohydrate site-directed conjugation of CVF to a monoclonal IgG specific to a cell-surface antigen of human ovarian cancer cells. The terminal galactosyl residues of CVF were selectively modified at C-6 by treatment with galactose oxidase, and the generated aldehyde groups were derivatized in situ with hydrazides containing either protected thiol or maleimide functional groups. The CVF derivatives were allowed to react with thiol groups introduced to the antibody by derivatization with 2-iminothiolane to yield carbohydrate site-directed CVF-antibody conjugates. In both cases, 30-40% of the antibody cross-linked to CVF to yield predominantly monovalent CVF-antibody conjugates. The purified immunoconjugates retained 70-75% of CVF activity and significant level of antigen-binding capacity. This is the first study to exploit the oligosaccharide chains of CVF for the preparation of active immunoconjugates.

AB - Cobra venom factor (CVF) can cause cell death by complement-mediated bystander cell lysis. Several studies have investigated CVF for application in cancer therapy by conjugating CVF to antibodies against tumor cell surface-specific antigens via the side-chain amino acid residues. In most cases, the activity of CVF was markedly impaired, presumably by modification of the factor B binding domain due to random derivatization. Since CVF is a glycoprotein and its oligosaccharide chains are distal to the factor B binding domain, coupling of CVF to antibodies through its oligosaccharide chains is expected to yield immunoconjugates with retention of CVF activity and elimination of the immunoreactivity of the terminal α-galactosyl residues. In this study, we investigated the carbohydrate site-directed conjugation of CVF to a monoclonal IgG specific to a cell-surface antigen of human ovarian cancer cells. The terminal galactosyl residues of CVF were selectively modified at C-6 by treatment with galactose oxidase, and the generated aldehyde groups were derivatized in situ with hydrazides containing either protected thiol or maleimide functional groups. The CVF derivatives were allowed to react with thiol groups introduced to the antibody by derivatization with 2-iminothiolane to yield carbohydrate site-directed CVF-antibody conjugates. In both cases, 30-40% of the antibody cross-linked to CVF to yield predominantly monovalent CVF-antibody conjugates. The purified immunoconjugates retained 70-75% of CVF activity and significant level of antigen-binding capacity. This is the first study to exploit the oligosaccharide chains of CVF for the preparation of active immunoconjugates.

UR - http://www.scopus.com/inward/record.url?scp=0035086610&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035086610&partnerID=8YFLogxK

U2 - 10.1021/bc000100u

DO - 10.1021/bc000100u

M3 - Article

C2 - 11312689

AN - SCOPUS:0035086610

VL - 12

SP - 271

EP - 279

JO - Bioconjugate Chemistry

JF - Bioconjugate Chemistry

SN - 1043-1802

IS - 2

ER -