Differentiation between human red cells of Pk and p blood types using Pseudomonas aeruginosa PA-I lectin.
BACKGROUND
The red cells of almost all human beings bear P antigen. Type P1 cells (around 75% of the population) contain P1 antigen in addition to P, and type P2 cells (around 25% of the population) contain only P. The red cells of only a few individuals are devoid of P: these cells may be of either Pk-positive (P1k and P2k[Pk]) or p type (the latter lack all the above-described antigens of the P system). Differentiation between them is of clinical importance, but there is a shortage of specific reagents. This article offers reliable means for differentiation.


METHODS
Agglutination of washed, papain-treated red cells of all the P types by PA-1 and soybean lectins and adsorption of the lectins onto the red cells were examined.


RESULTS
PA-1 strongly agglutinated papain-treated red cells. Examination of its interactions with red cells having different P system antigens revealed that Pk (both P1k and P2k) red cells of O, A, and B blood types were agglutinated significantly faster than p red cells. The agglutination intensities of Pk red cells of types O and A (most people) was considerably stronger than those of p red cells. P1 and P2 type red cell agglutination was intermediate (P1>P2). Adsorption tests with all the red cells, exhibited the same order of PA-1 affinities for the P system blood types: Pk>P1,>P2>p. The soybean lectin exhibited opposite behavior (p>P2>P1>Pl).


CONCLUSIONS
The galactose-binding lectins PA-1 and soybean may facilitate the determination of Pk and p red cells.
Sudakevitz
D
D
Department of Life Sciences, Bar-Ilan University, Ramat Gan, Israel.
Levene
C
C
Sela
R
R
Gilboa-Garber
N
N
D000017:ABO Blood-Group System / Q000032:analysis; D018829:Adhesins, Bacterial / Q000378:metabolism*; D002240:Carbohydrate Sequence; D006384:Hemagglutination; D006801:Humans; D037102:Lectins / Q000378:metabolism*; D008969:Molecular Sequence Data; D010127:P Blood-Group System / Q000032:analysis*
D000017:ABO Blood-Group System; D018829:Adhesins, Bacterial; D037102:Lectins; D010127:P Blood-Group System; C038692:adhesin, Pseudomonas