Abnormal Glycolipid Composition of Erythrocytes with a Weak P Antigen

Abstract

The erythrocytes of a normal man were agglutinated more weakly than normal cells by several anti-P(1)OO^k sera, and exhibited a decreased capacity to absorb these antibodies. Analysis of his erythrocyte glycosphingolipids revealed that the globoside (P antigen) content was less than 25% of normal, and trihexosyl ceramide (the Pk antigen) was 30-40% of normal. The ganglioside content of his erythrocytes was approximately four times normal and sialosylparagloboside was increased about sixfold. It appears that his erythrocytes are unable to synthesize normal quantities of trihexosyl ceramide, and that these serological and chemical features constitute a new phenotype in the P blood group system.

A hemolytic anti‐LKE associated with a rare LKE‐negative, “weak P” red blood cell phenotype: alloanti‐LKE and alloanti‐P recognize galactosylgloboside and monosialogalactosylgloboside (LKE) antigens

“…In contrast, there was a fivefold decrease in the Gb3/CDH ratio, consistent with decreased conversion of CDH→Gb3. A decrease in Gb3/CDH ratio, accompanied by increases in CDH and nLc4, is also reported for the weak P phenotype . As shown, relative neutral GSL expression in our patient and a known weak P sample was virtually identical (Table ).…”

“…The weak P phenotype is reported to show weakened P expression in titration studies with some examples of anti‐PP 1 P k . In titration studies, the patient had a significantly decreased titer with one alloanti‐P (titer, 8) relative to LKE‐N (n = 3; median titer, 16), LKE‐W (n = 4; titer, 16‐32), and LKE‐S cells (n = 4; titer, 32‐128) .…”

“…Our patient is the first known example of LKE‐N arising from a weak P phenotype and is only the second example of weak P characterized in the literature. The first weak P was identified serendipitously in a normal donor after routine phenotyping showed weaker agglutination with some anti‐PP 1 P k . Analysis of the donor's RBC GSLs showed a 30% decrease in globo‐GSL expression, accompanied by a two‐ to fourfold increase in CDH, nLc4, GM3, and total RBC ganglioside.…”

“…The etiology of the weak P phenotype is unknown. Kundu and coworkers hypothesized a partial block in α4GalT1, the α1,4‐galactosyltransferase responsible for Gb3 synthesis. As a result, weak P RBCs have a decrease in all globo‐GSLs with a compensatory increase in CDH, GM3, and neolacto‐GSLs (nLc4, snLc4) similar to that observed in the P k and p phenotype (Fig.…”

Sphingolipids: Modulators of HIV-1 Infection and Pathogenesis

“…Therefore, we further investigated the role of GM3 in HIV-1 entry by examining effect of GSL depletion from the p-lymphocytes, which do not express any Gb3 and the next upstream globoseries GSL, Gb4 due to absence of the enzyme, UDP galactose: lactosylceramide-galactosyl transferase (Hex3Cersynthase) (Marcus et al, 1976;Kijimoto-Ochiai et al, 1977;Kundu et al, 1978Kundu et al, , 1980Kundu et al, , 1981. However, p-lymphocytes express exceptionally high levels of the ganglioside GM3 , which is also the major ganglioside of normal lymphocytes (Kundu et al, , 1980Marcus et al, 1976Marcus et al, , 1981.…”