Purification of an antibody‐like protein from the sea star Asterias rubens (L.)

Abstract

Cells from sea star (Asterias rubens) axial organs stimulated with trinitrophenyl (TNP) or fluoresceinyl-haptened polyacrylamide beads and subsequently stimulated in vitro with the same antigen produced and released a specific antibody-like protein which induced lysis of haptened sheep erythrocytes in the presence of serum complement. The anti-TNP antibody-like protein isolated by ammonium sulfate precipitation, gel filtration and affinity chromatography exhibited a single precipiting peak after crossed immunoelectrophoresis against rabbit antiserum to partially purified culture supernatant. The anti-TNP antibody-like protein gave a specific affinity precipitate in crossed affino-electrophoresis using a p-nitrobenzoyl-substituted gel. The analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under both reducing and nonreducing conditions evidenced a unique 30-kDa polypeptide chain. According to gel filtration experiments, the molecular weight of the major component isolated by affinity chromatography was about four times higher. Therefore, the antibody-like molecule could be a tetrameric protein devoid of any disulfide bond.

Evidence of Kappa genes in the sea-star Asterias rubens (Echinoderma)

“…Second experiments used hapten-carrier conjugates and revealed the role of B-like, T-like cells, phagocytic cells and mammal complement (mouse C3 and C5 components have just been found) in the specific sea star immune response, within the axial organ [7]. At last, antibody-like factor was isolated and purified [12]: in 2000, it was shown that it presented homologies with human Kappa-like [8]. In 2007 G. Coteur mention similar results, always, with Asterias rubens [11].…”

Innate and Adaptative Immunity in the Sea-Star Asterias Rubens

“…Although all efforts to find a primitive form of immunoglobulin in sea-urchin genome (Rast et al, 2006) have been unsuccessful, it is the first time, we present arguments indicating that vertebrate immunoglobulin Kappa genes are present in an invertebrate and Deuterostomes. It appears that the antibody factor has a Science Publications AJI molecular weight of 120-130.000 daltons (Delmotte et al, 1986) with 4 sub-units of 30.000 daltons each: it could be composed of 4 « kappa chains ».…”

“…1). In cooperation with the sea-star complement, they initiate the "antibody factor" (Delmotte et al, 1986) recently kappa genes were discovered in the sea-star A. Rubens (Leclerc et al, 2011). We now present the DNA structure of these genes in immunized and control sea-stars.…”

“…We recall that antibody factor was isolated and purified (Delmotte et al, 1986). In 2000, it was shown that it presented homologies with human kappa-like (Leclerc, 2000).…”

A TRUE “CANDIDATE IG KAPPA GENE” IN THE SEA-STAR: <i>ASTERIAS RUBENS</i> (ECHINODERMA)

“…Sequences were assembled using Velvet (Zerbino and Birney, 2008). Delmotte et al (1986), antibody factor was isolated and purified. Leclerc (2000), it was shown that it presented homologies with human kappa-like.…”