METALLOTHIONEIN EXPRESSION IN PLACENTAL TISSUE IN MENKES DISEASE - ANIMMUNOHISTOCHEMICAL STUDY

Menkes' disease is a recessive X-linked disturbance of copper metaboli sm, resulting in accumulation of copper in several extra-hepatic tissu es including the placenta. Metallothionein (MT) is a low-molecular wei ght protein with a high affinity for group II metal ions, such as copp er. Its synthesis is induced by the presence of the ions. The aim of t his study was to investigate the pattern of the MT immunoreactivity in placental tissue obtained from women at-risk of Menkes' disease in or der to examine whether the MT occurrence and distribution may reflect the copper content. Placental tissue from six women with a family hist ory of Menkes' disease, from 4 women without a family history, and fro m 2 hydatiform moles was studied. Positive MT immunostaining was found to be independent of the length of fixation, whether the tissue sampl es were fixed in 4% buffered formaldehyde or Bouin's fixative. The avi din-biotin-complex (ABC)-technique was used. The copper content was me asured by neutron activation analysis (NAA). In all placental tissue s ections positive MT immunostaining appeared only in the trophoblast an d only in proliferating cells. In placental tissue sections obtained f rom foetuses and children affected by Menkes' disease an additional MT immunostaining appeared in the Hofbauer cells of the chorionic villi. This staining was associated with an increased content of copper as m easured by NAA. We conclude that the immunohistochemical demonstration of MT reflects the copper content and may be useful in pre- and postn atal diagnosis of Menkes' disease.