YATABE M Dept. of Pediatrics, AUSM, 医学部, 講師 (70158012)
KOBAYASHI Y Dept. of Pediatrics, AUSM, 医学部, 講師 (30133937)
TAHARA M Dept. of Pediatrics, AUSM, 医学部, 助手 (10188401)
川原田 良彦 秋田大学, 医学部, 助手 (10091802)
OKUHARA E Dept. of Biochemistry, AUSM, 医学部, 教授 (60000915)
KAWARADA Y Dept. of Biochemistry, AUSM (KAWAZOE,Yosh)
|Budget Amount *help
¥4,400,000 (Direct Cost: ¥4,400,000)
Fiscal Year 1987: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1986: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1985: ¥3,100,000 (Direct Cost: ¥3,100,000)
Chediak-Higashi syndrome (CHS) is an autosomal recessive disease characterized by incomlete oculocutaneous albinism, susceptilility to infections and the presence of gigantic cytoplasmic granules or lysosomes in leukocytes and many other cell types.
Although the fundamental defect at the molecular level in this disease remains unknown, it has been suggested by previous workers that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane-microtubule interaction. In the present study, we have obtained pure lysosome fractions from black (normal) and beige (CHS) mice liver by Percoll density gradient centrifugation method, in which the postnuclear supernatant was incubated with 1 mM CaC1_2 to separate lysosomes from mitochondria (Yamada et al. 1984), and identified them by assays of marker enzymes, including <beta>-N-acetylglucosaminidase, arylsulfatase A&B, BANA hydrolase, succinic INT reductase, monoamine oxidase, glucose-6- phosphatase and urate oxidase, and also by the electronmicroscopy. Specific activities of marker enzymes in lysosome fractions, i.e. <beta>-N-acetylglucosaminidase, arylsulfatase A&B and BANA hydrolase, expressed as percentages of the total activity of each enzyme in the liver homogenate, were less in specimens from beige mice than from black mice, suggesting an increased susceptibility to trauma of beige (CHS) lysosomes. The protein analysis of lysosomal membranes is now under way.
We have also studied on the effects of colchicine and cytochalasin B, which acts on microtubules and microfilaments respectively, upon fetal fibroblasts, and found no marked differences in the change of cell size, induced by these reagents, between normal and beige (CHS) cells.