Quantitative immunochemical evaluation of fish metallothionein upon exposure to cadmium.

Efficient implementation of an environmental biomarker requires multi-annual comparability over a wide geographical range. The present study improved the comparability of a quantitative competitive metallothionein (MT) enzyme-linked-immuno-sorbent-assay (ELISA) in the sentinel fish Lithognathus mormyrus by introducing to the assay recombinant MT and beta-actin standards. Commercial antibodies for cod MT and mammalian actin were implemented.

'Cup cell disease' in the colonial tunicate Botryllus schlosseri.

A new progressive, fatal disease called 'cup cell disease' was characterized in ex situ cultures of Botryllus schlosseri, a colonial tunicate. The disease originated as a few dark spots growing within zooids. The infected colonies then started to deteriorate, morphologically diagnosed by ampullar retraction, lethargic blood circulation and by a swollen and soft tunic matrix.

Environmental split between germ cell parasitism and somatic cell synergism in chimeras of a colonial urochordate.

Colonies of the urochordate Botryllus schlosseri may fuse upon contact if they share common alleles on the highly polymorphic fusibility/histocompatibility locus. While, in these chimeras, one of the partners is usually morphologically eliminated (resorbed), circulating totipotent cells of the inferior genotype on the resorption phenomenon may parasitize either the soma or the germ line of the winner. Here, we show an environmental split of the two stem cell lineages that may develop germ cell parasitism vs somatic cell cooperation.