HYBRIDOMA Volume 9, Number 4, 1990 Mary Ann Liebert, Inc., Publishers
Antigen Defined by Monoclonal Antibody KMOl
Characterization of
an
YOSHIAKI KANO,1 TOMOKUNI TANIGUCHI,1 YAHIRO UEMURA,1 KAZUMASA YOKOYAMA,1 KUNIO UESAKA, MASAHIRO YAMAMOTO,2 HARUMASA OHYANAGI,2 and YOICHI SAITOH2 'Research Division, The Green Cross Corporation, Hirakata, Japan 2The First Department of Surgery, Kobe University School of Medicine, Kobe,
Japan
ABSTRACT We have isolated an antigen defined by the monoclonal KMOl from tissue culture supernatant as a glycoprotein and from cancer cells as a glycolipid. The antigenic determinant was a carbohydrate. Antibody KMOl inhibited the binding activity of 19-9 to CA19-9, but 19-9 antibody did not inhibited the binding activity of KMOl to KMOl antigen. The glycolipid antigen of KMOl was a monosialoganglioside and was separated into 3 components on thin layer chromatography. The 19-9 antibody reacted with one of the components. These results suggest that the KMOl antigen is similar to but not identical to CA19-9.
antibody
INTRODUCTION
The development of monoclonal antibody technology has allowed a more precise analysis of the antigenic profile of new tumor markers that had not previously been detected by conventional polyclonal antibodies. Examples of these new tumor for are CA19-9 gastrointesinal carcinoma (1), CA125 for antigens ovarian carcinoma (2), DU-PAN-2 for pancreatic carcinoma (3), CA15-3 for breast carcinoma (4,5), CSLEX-1 for adenocarcinoma of lung (6), and TAG-72 for breast and colorectal carcinomas (7). The murine monoclonal antibody KMOl was generated using colon Previous studies cancer cell line COLO 201 as the immunogen (8). have demonstrated that the antigen recognized by KMOl was distinct from currently known tumor markers such as AFP, CEA, (32microglobulin and ferritin. The KMOl antigen has been detected in the serum of approximately 80% of pancreatic carcinoma patients, 50% of bile duct carcinoma patients, 50% of hepatoma 363
patients and 30% of cololectal carcinoma patients. These facts show that the antigen is a useful tumor marker for these Monoclonal antibody KMOl inhibited the binding of carcinomas. 19-9 antibody to cancer cells, indicating the close relationship of these two monoclonal antibodies. The fact that the antigenicity of KMOl antigen or CA19-9 was diminished by sialidase treatment confirms similar reactivity of the antibodies. We report here the isolation and characterization of the KMOl antigen from tissue culture supernatant and from cancer cells, and the analysis as for the immunological differences between the KMOl antigen and the previously known tumor maker, CA19-9. Based on the data presented here and in a previous paper, the KMOl antigen in tissue culture supernatant and patient serum is a high-molecular-weight glycoprotein and its antigenic determinant is not a protein but a sugar moiety. Though the antigen is also found as a glycolipid, it is unclear whether or not the sugar antigenic determinant on the glycolipid is identical to that of the glycoprotein. The differences of specificity between KMOl and 19-9 antibodies are also described. MATERIALS AND METHODS
Materials: A mouse hybridoma which produces antibody KMOl (IgGl,/
Antigen Defined by Monoclonal Antibody KMOl
Characterization of
an
YOSHIAKI KANO,1 TOMOKUNI TANIGUCHI,1 YAHIRO UEMURA,1 KAZUMASA YOKOYAMA,1 KUNIO UESAKA, MASAHIRO YAMAMOTO,2 HARUMASA OHYANAGI,2 and YOICHI SAITOH2 'Research Division, The Green Cross Corporation, Hirakata, Japan 2The First Department of Surgery, Kobe University School of Medicine, Kobe,
Japan
ABSTRACT We have isolated an antigen defined by the monoclonal KMOl from tissue culture supernatant as a glycoprotein and from cancer cells as a glycolipid. The antigenic determinant was a carbohydrate. Antibody KMOl inhibited the binding activity of 19-9 to CA19-9, but 19-9 antibody did not inhibited the binding activity of KMOl to KMOl antigen. The glycolipid antigen of KMOl was a monosialoganglioside and was separated into 3 components on thin layer chromatography. The 19-9 antibody reacted with one of the components. These results suggest that the KMOl antigen is similar to but not identical to CA19-9.
antibody
INTRODUCTION
The development of monoclonal antibody technology has allowed a more precise analysis of the antigenic profile of new tumor markers that had not previously been detected by conventional polyclonal antibodies. Examples of these new tumor for are CA19-9 gastrointesinal carcinoma (1), CA125 for antigens ovarian carcinoma (2), DU-PAN-2 for pancreatic carcinoma (3), CA15-3 for breast carcinoma (4,5), CSLEX-1 for adenocarcinoma of lung (6), and TAG-72 for breast and colorectal carcinomas (7). The murine monoclonal antibody KMOl was generated using colon Previous studies cancer cell line COLO 201 as the immunogen (8). have demonstrated that the antigen recognized by KMOl was distinct from currently known tumor markers such as AFP, CEA, (32microglobulin and ferritin. The KMOl antigen has been detected in the serum of approximately 80% of pancreatic carcinoma patients, 50% of bile duct carcinoma patients, 50% of hepatoma 363
patients and 30% of cololectal carcinoma patients. These facts show that the antigen is a useful tumor marker for these Monoclonal antibody KMOl inhibited the binding of carcinomas. 19-9 antibody to cancer cells, indicating the close relationship of these two monoclonal antibodies. The fact that the antigenicity of KMOl antigen or CA19-9 was diminished by sialidase treatment confirms similar reactivity of the antibodies. We report here the isolation and characterization of the KMOl antigen from tissue culture supernatant and from cancer cells, and the analysis as for the immunological differences between the KMOl antigen and the previously known tumor maker, CA19-9. Based on the data presented here and in a previous paper, the KMOl antigen in tissue culture supernatant and patient serum is a high-molecular-weight glycoprotein and its antigenic determinant is not a protein but a sugar moiety. Though the antigen is also found as a glycolipid, it is unclear whether or not the sugar antigenic determinant on the glycolipid is identical to that of the glycoprotein. The differences of specificity between KMOl and 19-9 antibodies are also described. MATERIALS AND METHODS
Materials: A mouse hybridoma which produces antibody KMOl (IgGl,/
