Ki-67 (MIB 5) immunostaining of mouse lung tumors induced by 4-nitroquinoline 1-oxide.
We immunostained mouse lung tumors using a mouse monoclonal antibody against recombinant Ki-67 antigen (clone; MIB 5) to establish an MIB 5 immunostaining method and to determine the extent of MIB 5 labeling to monitor cell proliferation activity in mouse lung tumors. A/J mice, treated with 4-nitroquinoline 1-oxide, were killed after 18 months. One hour before killing, bromodeoxyuridine (BrdU) was injected intraperitoneally. Lung tissues including tumors were fixed with phosphate-buffered 4% paraformaldehyde and embedded in paraffin. For MIB 5 immunostaining, two antigen-retrieval buffers, citrate buffer pH 6 and TRIS-HCl buffer pH 9.5 containing 5% urea, were tested, and constant and reproducible staining was obtained only with the TRIS-HCI buffer. The mean values of the MIB 5-positive cell index (PCI), the BrdU labeling index (LI), and the mitotic cell count for adenocarcinomas were 4.6%, 2.3%, and 7/mm2, and those for adenomas were 1.2%, 0.7%, and 1.3/mm2, respectively. Each of these values was significantly higher for adenocarcinomas than for adenomas. A close correlation was seen between the MIB 5 PCI and the BrdU LI for adenocarcinomas and adenomas and between the MIB 5 PCI and the mitotic cell count in adenocarcinomas. Thus, MIB 5 immunostaining is a useful method for assessing the proliferative activity of mouse tumor tissues.
Ito
T
T
Department of Pathology, Yokohama City University School of Medicine, Yokohama, Japan.
Mitui
H
H
Udaka
N
N
Hayashi
H
H
Okudela
K
K
Kanisawa
M
M
Kitamura
H
H
D015112:4-Nitroquinoline-1-oxide / Q000633:toxicity; D000230:Adenocarcinoma / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D000236:Adenoma / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D000911:Antibodies, Monoclonal; D001973:Bromodeoxyuridine / Q000378:metabolism; D002273:Carcinogens / Q000633:toxicity; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism*; D008175:Lung Neoplasms / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D011994:Recombinant Proteins / Q000378:metabolism
D000911:Antibodies, Monoclonal; D002273:Carcinogens; D019394:Ki-67 Antigen; D011994:Recombinant Proteins; D015112:4-Nitroquinoline-1-oxide; D001973:Bromodeoxyuridine