A monoclonal antibody inhibits adhesion to fibronectin and vitronectin of a colon carcinoma cell line and recognizes the integrins alpha v beta 3, alpha v beta 5, and alpha v beta 6.
Using whole viable human colon carcinoma HT29 cells as immunogen, we produced a monoclonal antibody (mAb) termed 69-6-5. The antibody was functionally selected on its anti-cell-spreading activity. By immunoprecipitation of surface radiolabeled cell lysates from HT29-D4 cells (an HT29 cell clone), mAb 69-6-5 recognized a molecular complex resembling integrin heterodimers. Sequential immunodepletions with mAb to the integrin alpha v subunit demonstrated that this complex was composed of alpha v-containing integrins. Accordingly, mAb 69-6-5 reacted with integrin alpha v beta 3 immunopurified from melanoma cells and integrins alpha v beta 5 and alpha v beta 6 immunopurified from pancreatic carcinoma cells. In cell adhesion assays, the 69-6-5 mAb was able to inhibit strongly in a dose-dependent manner arginine-glycine-aspartic acid-mediated adhesion of HT29-D4 cells to vitronectin, fibronectin, or ProNectin F but not to laminin or collagen. Immunoprecipitations with beta chain-specific antisera indicated that these cells express integrins alpha v beta 5 (receptor for vitronectin) and alpha v beta 6 (receptor for fibronectin) but neither alpha v beta 1 nor alpha v beta 3. In summary, these results indicated that mAb 69-6-5 reacts with several alpha v integrins and that it can effectively interfere with the adhesive functions of at least alpha v beta 5 and alpha v beta 6, which represent the major receptors on HT29-D4 cells responsible for their adhesion on vitronectin and fibronectin.
Lehmann
M
M
Institut de Chimie Biologique, ER CNRS 079, Université d'Aix-Marseille, France.
Rabenandrasana
C
C
Tamura
R
R
Lissitzky
J C
JC
Quaranta
V
V
Pichon
J
J
Marvaldi
J
J
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D000951:Antigens, Neoplasm; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D002465:Cell Movement; D003110:Colonic Neoplasms; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D005353:Fibronectins; D006023:Glycoproteins; D006801:Humans; D016023:Integrins / Q000032:analysis / Q000276:immunology / Q000502:physiology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016024:Receptors, Cytoadhesin / Q000276:immunology / Q000502:physiology; D019030:Receptors, Vitronectin; D014407:Tumor Cells, Cultured; D019096:Vitronectin
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000939:Epitopes; D005353:Fibronectins; D006023:Glycoproteins; D016023:Integrins; D016024:Receptors, Cytoadhesin; D019030:Receptors, Vitronectin; D019096:Vitronectin; C064660:integrin alphaVbeta5; C073878:integrin alphavbeta6