Kenichi Uobe

Detection of HPV in Japanese and Chinese oral carcinomas by in situ PCR

Human papillomavirus (HPV) is established as the cause of almost 100% of cervical carcinomas. However, the association of HPV with oral squamous cell carcinomas (SCCs) is less well understood. We examined the prevalence of HPV in oral SCCs in samples of Japanese and Chinese populations. Using in situ polymerase chain reaction (PCR) analysis (MY09 and MY11 consensus primers), HPV was detected in the nucleus of epithelia and tumor cells in oral lesions. Analysis revealed the specific presence of HPV DNA in all cases of SCC in our Japanese (10/10) and Chinese (10/10) population samples. These results suggest that HPV infection could be one of several risk factors contributing to oral SCC in Japanese and Chinese.

Serum Proteins and Secretory Component in Human Carious Dentin

By the use of the peroxidase-labeled antibody method, significant localization of IgG, IgA, albumin and transferrin was demonstrated in the deep lesion of 20 carious teeth, where the secretory component was absent. These serum proteins formed a distinct zone, surrounding the overlying, shallow lesion infected with bacteria.

Trimethylsilylation reaction of prostaglandin-E methyl ester with various trimethylsilylating reagents

Abstract Gas chromatographic investigation of the time course of the trimethylsilylation reaction of prostaglandin-E methyl ester (PGE-Me) with trimethylsilylimidazole-piperidine (PIP), N,O-bis(trimethylsilyl)trifluoroacetamide-PIP and other silylating reagents revealed that these reagents do not always give a single product. The reaction products were characterized by gas chromatography-mass spectrometry as the trimethylsilyl derivatives of PGA-Me, PGB-Me, PGE-Me, 9-enol-PGE-Me and 11-piperidyl-PGA-Me.

Thermal degradation of sugars in a gas chromatographic injection port

Abstract The degradation products of glucose formed during gas chromatographic analysis of fermentation liquids of Streptococcus mutans, S. mitis and S. salivarius were investigated. A total of 18 sugars from mono- to trisaccharides were also examined by direct injection of aqueous solutions of the carbohydrates into a gas chromatograph packed with porous polymer Chromosorb 101. The main degradation products, including acetic acid and furfural derivatives, were identified by gas chromatography-mass spectrometry.

Monoclonal Antibodies Against Gingival Components

The aim of this study was to produce and characterize monoclonal antibodies against human gingival epithelial cells and gingival fibroblasts. By using these whole cells as immunogens, we were able to generate a large number of monoclonal antibodies reacting with tissue antigens, in particular antibodies that reacted with desmosomes (MoAbs 7 and 8) and basement membrane (MoAb FB-1) antigens. MoAbs 7 and 8 produced from epithelial cells stained cell membranes of epithelium and desmosomes, respectively, as shown by light and immunoelectron microscopy. The epitopes to which MoAbs 7 and 8 were reactive were stable against various treatments; only periodate oxidation abolished the tissue reactions with MoAb 8. Extraction of gingiva with SDS or NP-40, SDS-PAGE analysis, and Western blotting showed that the MoAb 8 identified an antigen with a molecular weight of 100,000 daltons. MoAb FB-1 produced from fibroblasts immunolabeled the basement membranes. The FB-1 antigen was clearly different from any of the known ubiquitous basement membrane components, such as type IV collagen, laminin, and fibronectin. Examination of the distribution and localization of the antigen showed that it was present in the basement membrane beneath stratified squamous epithelium. FB-1 did not react with any of types I-VI collagens in ELISA, but immunoelectron microscopy showed that the antigen reacting with FB-1 was present in the lamina fibroreticularis of the basement membrane and was comprised of collagen-like fibers. These results suggest the possible existence of a new collagen other than types I-VI in the basement membrane beneath stratified squamous epithelium.

A novel immunohistochemical technique for the detection of human oral carcinomas transplanted in nude mice using mouse monoclonal antibodies

Abstract We have developed a new immunostaining technique specifically for the detection of human tumors transplanted into nude mice using mouse monoclonal antibodies (MoAbs) produced in our laboratory. The formation of a molecular complex consisting of three components (mouse MoAb or hybridoma supernatant, biotin-labeled anti-mouse immunoglobulins, and normal nude mouse serum) markedly reduced background staining and enhanced specific reaction with the transplanted tumors in nude mice. When MoAb production by electrofusion was screened with this new method, the incidence of hybridoma supernatant reactive with sections of transplanted tumor was 2.3 per 100 wells immunostained. These results suggest that production of MoAbs using transplanted tumors is immunohistochemically possible and that this method may provide a new means for developing useful tumor markers.

An immunopathological study of periodontal disease. Chronic sensitization by oral bacteria and periodontitis

辺縁性歯周炎の発症と経過に免疫現象が関与することが明らかにされている。その経過にみられる免疫現象は, 口腔内細菌による遷延感作あるいはより複雑な機序に基づくかもしれない。著者らはヒトロ腔内細菌を用いてモルモットを遷延感作したところ, 特異抗体産生は, 3ヵ月後に最高に達し, それ以降は漸時減少した。また, 辺縁性歯周炎罹患者血清中のヒトロ腔内細菌に対する特異抗体と免疫グロブリン (IgG) 含有量, さらに自己歯肉組織に対する特異抗体が存在するかどうかを健常者血清中のそれらと比較して検索した結果, 細菌特異抗体量は平均値では増加の傾向を示すが, 極端な最高ならびに最低値の症例を除くと減少の傾向を, しかし免疫グロブリン (IgG) 含有量は増加を示した。そして歯肉組織に対する特異抗体は全ての症例において検出されなかった。これらのことから, 本疾患の経過中に動物実験でみられたような遷延感作成立の可能性は否定的であった。

Ultrastructural study on dog gingival epithelium using monoclonal anibody - Application of immunoelectron microscopic method and comparative study on each cells of stratified squamous epithelium.

イヌ歯肉上皮細胞の細胞膜の微細構造を解明する一助として, 細胞膜に対するモノクロ抗体D1の対応抗原の局在性を免疫電顕を応用して観察した。間接免疫ペルオキシダーゼ法の結果, 凍結切片上では棘細胞の細胞膜に強い反応陽性所見が認められたが, 基底細胞の基底膜側および角質細胞の細胞膜は反応が陰性であった。高倍率の観察ではdesmosomeのattachment plaqueとそれに続く形質膜に反応陽性所見が認められ, 細胞質内小器官には反応産物は認められなかった。また酵素処理により遊離細胞とした場合も同様な結果となったことからモノクロ抗体D1の対応抗原は細胞膜表面を構成している物質であり, 歯肉上皮細胞の細胞膜は分化する際にその構成に変化が起こることが示唆される。