The Anti-N Lectin of Bauhinia Purpurea

[摘要] Seeds of Bauhinia purpurea , var. alba , contain a lectin specific for the N antigen of human erythrocytes. These seeds are available commercially, and from them, by saline extraction and 2 precipitations with alcohol in the cold (plus occasionally the addition of a little melibiose), a routinely usable anti-N reagent can be prepared. This reagent, tested in parallel with a good rabbit anti-N against 265 random bloods, gave the correct result in every case. Dialysis of Bauhinia extracts removes a diffusible substance which is generally present and which is necessary to prevent the lectin from reacting nonspecifically with all human erythrocytes. Various sugars, including galactose and melibiose, will also inhibit this nonspecific reaction. The inhibition reactions point to a close chemical similarity of the Bauhinia -detectable receptor, common to all human erythrocytes, and the B receptor, which is restricted to B and AB.

[学科分类] 生物科学（综合）