Copper-thionein in leucocytes.
Upon incubation of peripheral leucocytes with copper sulphate a dramatic cellular copper uptake reaching levels of 25-50-fold compared to that of the natural copper content was measured. The orange-red fluorescence of the copper-treated white blood cells was assigned to the formation of Cu(I)-thiolate clusters in Cu(I)-thionein. A protein of 6-8 kDa was isolated from homogenized bovine leucocytes and characterized by its electronic absorption and amino acid composition to be identical to the above Cu(I)-thionein. More than 70% of the intracellular copper was attributed to this protein in its monomeric and polymeric form. Cu-thionein formation was more pronounced in monocytes than in granulocytes. As most intriguing phenomenon, the release of this Cu-thionein from leucocytes, was also noticed. The occurrence of Cu-thionein in leucocytes and the excretion of the intact Cu(I)-thiolate protein is of considerable interest with respect to the observed elevated copper levels in white blood cells and plasma during tumor malignancies and inflammatory processes.
Hartmann
H J
HJ
Anorganische Biochemie, Physiologisch-Chemisches Institut, Universität Tübingen, Federal Republic of Germany.
Schechinger
T
T
Weser
U
U
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D002850:Chromatography, Gel; D003300:Copper / Q000097:blood*; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D008668:Metallothionein / Q000097:blood*
D000596:Amino Acids; C007121:copper thionein; D003300:Copper; D008668:Metallothionein