In this study we tested the seeds of uncultivated plants for lectin activity. Extracts prepared from the seeds of 167 forb species were tested against human red cell samples. Extracts of 54 species agglutinated unmodified or enzyme-modified red cells. In nine species, the hemagglutinating lectin activity could be neutralized by N-acetyl-D-galactosamine, mannose, or glucose.

SHORT COMMUNICATIONS REPORT ON ACTIVITY OF LICHEN LECTINS Agglutination or clumping of red blood cells by plant extracts were reported by Stillmark (1888). Boyd & Shapleigh (1954) subsequently introduced the term lectin (from the Latin legere, to pick or choose) to describe haemagglutinins obtained from plants. Lectins in lichen extracts have been reported by Estola & Vartia (1955) and by Barrett & Howe (1968). Although these authors concluded that they were unable to demonstrate specificity in the lichen lectins, Barrett & Howe suggested that further testing was warranted, as did Gold & Balding (1975). Our purpose was to collect fresh lichen samples and then identify and test them for lectin activity. Materials and Methods Lichens were collected in the states of Alaska, Missouri and Washington, U.S.A. and in the Yukon Territory, Canada. Specimens of Cladonia coccifera, Dermazocarpon miriatum, Placynthium asperellum, (syn. P. aspralile) Punctelia rudecta (syn. Parmelia rudecta) and Xanthoria candelaria were collected in Missouri, Hypogymnia physodes in Washington, and Cetraria islandica, Cladina mitis (syn. Gadonia mitis), Cladonia deformis, Cladonia pleurota, Umbilicaria torrefacta and Xanthoparmelia centrifuga (syn. Parmelia centrifuga) in the Yukon Territory. The remaining species were collected in Denali and Glacier Bay National Parks, Alaska. Specimens were identified according to morphological and chemical criteria. Voucher material has been retained at the Smithsonian Institution (U.S.A.). Extracts of each species were prepared as 10% suspensions of ground or chopped material in phosphate buffered saline (PBS) pH 7 • 0. After 30 min incubation at 22°C, the suspensions were centrifuged and the supernatant removed for immediate testing. The extracts were then tested against 15 red cell samples including (1) group A and B cells; (2) group O cells positive for the antigens, M, N, P,, Le a , Le b , I and i; (3) T, Tn, Tk and NOR types of polyagglutinable cells; (4) Loxosceles reclusa venomtreated group O cells and ficin-treated group O and Tk polyagglutinable cells. Group A 2 cells and O h cells were used in selected tests. Serological tests were performed in 10 x 75 mm glass test tubes using equal volumes of extract and 2% red cell suspension in PBS. The tests were centrifuged after incubating for 10 and 60 min at room temperature and then examined for agglutination. Reactions were graded from negative to 4 + (maximum agglutination) and recorded. Lectin dilutions giving 1 + to 2 + reactions were selected for inhibition tests. These were performed using equal volumes of lectin and 0 1M solutions of the following carbohydrates: D-glucose, D-mannose, D-galactose, L-fucose, D-fucose, iV-acetyl-D-galactosamine, N-acetyl-D-glucosamine, AT-acetylneuraminic acid. Lectin-carbohydrate mixtures and a lectin PBS-positive control were incubated for 60 min at room temperature before the addition of the indicator cells. Reactivity of tests was compared to the positive control as described above. Table 1 lists the non-reactiv...

A capillary technique is described for economical Rh-phenotyping of large numbers of blood samples using diluted antisera and 4% ficin solution. This system is no more time consuming that conventional tube techniques, since enzyme premodification of the cells is not required.