JOURNAL OF INVERTEBRATE PATHOLOGY 43, 226-233 (1984) Humoral Lectins in the Scorpion Vaefovis confuscius: A Serological Characterization GERARDO RAUL VASTA’ Department of Biochemistry, Medical University of South Carolina. 171 Ashley Avenue, Charleston, South Carolina 29425 AND ELIAS COHEN Department of Laboratory Medicine, Roswell Park Memorial Institute, 666 Elm Street, Buffalo, New York, 14263 Received March 21, 1983; accepted June 23, 1983 Serum of the scorpion Vaejovis confuscius (Vaejovidae) exhibited agglutinating activity when tested with a variety of untreated and enzyme-treated vertebrate erythrocytes. Bird and reptile erythrocytes were no longer agglutinated by V. confuscius as well as Centruroides sculpturatus (Buthidae) and Limulus polyphemus sera after treatment with neuraminidase. Crossed absorption experiments revealed the presence of multiple lectins in V. confuscius serum and this wascon- firmed by hemagglutination-inhibition experiments. Sialic acids, their derivatives, and sialocon- jugates were the best inhibitors for both V. confuscius and C. sculpturatus lectins although other N-acylamino compounds (N-acetyl-o-galactosamine, N-acetyl-o-ghicosamine, and N-acetylmu- ramic acid) also inhibited. C. sculpturatus exhibited an additional lectin fraction specific for ga- lactans. These specificities for substances widely distributed in procaryofic cells might give clues about the biological role of chelicerate lectins. KEY WORDS: lectin; scorpion; sialoconjugates; Vaejovis confuscius; Centruroides sculpturatus; Limulus polyphemus. species are very primitive marine arthro- pods considered as “living fossils.” Since all the chelicerates constitute a very con- servative group in their morphokq&ical as- pects (St#rmer et al,, 19S5), we becamem- terested in investigating the presence of serum lectins in various species of chelic- erates in order to see if this conservative trend was extensive to the specificity of their serum lectins. At the present time, all species studied, which include horseshoe crabs (Cohen, 1968; Pardoe et al., 1970; Roche and Munsigny, 1979;Shim&u et al., 1977,1979;Bishaye and Dorai, 1980), scor- pions (Vasta et al., 1982;Vasta and Cohen 1980,1982,1983a,b; Vastaand Marchalonis 1983), whip scorpions (Vasta and Cohen 1983-c)) and spiders (Vasta and Cohen, un- publ.) exhibit multiple serum lectins and among them, fractions which dare specific INfRODlJCTlON Scorpion serum lectins have become a subject of interest in relatively recent years (Brahmi and Cooper, 1974; Cohen et al., 1979a,b; Vasta et al., 1982; Vasta and Cohen, 1980;1982;1983a,b; Vastaand Mar- chalonis, 1983) in relation to the sialic acid- specific lectins detected and characterized in the merostome Limulus polyphemus (Cohen, 1968; Marchalonis and Edetman, 1968;Pardoeet al., 1970; Nowak and Bar- ondes, 1975; Roche and Monsigny, 1979; Pistole, 1979). L. polyphemus and related ’ G.R.V. is from the Consejo National 4~ Imwti- gaciones CientIficas y T&nicas de la Re&M Ar- gentina and is a recipient of Fogarty International Fel- lowship (NIH) 1 FOS TWO3155-01. To whom corre- spondence should be sent. 226 0022-201 l/84 $1.50