Sandra S. Ellisor

Does Anti‐Jra Cause Hemolytic Disease of the Newborn?

Abstract. A Jr(a‐) Japanese female developed anti‐Jra during her first pregnancy. Both father and infant red cells were Jr(a+), and anti‐Jra was eluted from the infants red cells. The antibody was determined to be IgGl. Hemolysis could not be definitively established from the clinical data. The pitfall of using the presence of jaundice as the sole evidence for hemolysis is emphasized. We conclude that the present case, and other previously reported cases, do not unequivocally establish that anti‐Jra causes significant hemolytic diesease of the newborn (HDN). Amniocentesis probably should not be performed during the pregnancy of mothers sensitized to Jra antigen. Jra HDN is probably a mild disease, like ABO HDN.

Autoantibodies Mimicking Anti‐Jkbplus Anti‐Jk3 Associated with Autoimmune Hemolytic Anemia in a Primipara Who Delivered an Unaffected Infant

Abstract. A serum sample from a nontransfused 2 5‐year‐old Caucasian primipara contained weak anti‐Jkbplus anti‐Jk3. The direct antiglobulin test on the patients red cells was strongly positive. Anti‐Jkbwas recovered in a heat eluate. An ether eluate contained anti‐Jk3. Her red cells typed as Jk(a‐b+)Jk:3. The anti‐Jkband anti‐Jk3 reactivity was completely absorbed both by red cell samples lacking and red cells possessing the corresponding antigens, indicating these antibody specificities to be of the mimicking variety. At 41 weeks gestation she delivered a normal, healthy infant with no detectable serum or cell bound antibody.

Characteristics of an antibody causing agglutination of M-positive non-enzymatically glycosylated human red cells.

An alloagglutinin was identified in the serum of an M‐negative diabetic patient. The agglutinin reacted with all commercial M‐positive red cell samples. Routine cross‐matches showed no incompatibility. This anti‐M would only agglutinate M‐positive red cell samples that had been incubated in 2% glucose for a minimum of 2 h at 37°C, 2 days at 22°C, or 1 week at 4°C. Reactive red cell samples, when washed and incubated in saline, gradually became non‐reactive. This antibody reacted optimally in low ionic strength solution at 16°C for 20 min where MM red cells were agglutinated to a titer of 256, score 85; and MN red cells were agglutinated to a titer of 128, score 66. The antibody was denatured by 2‐mercaptoethanol and was inhibited by a crude M tryptic isolate and by 2 % glucose, but not by other sugars prepared at a 2% concentration.

Auto-anti-A1: another cause of ABO discrepancy.

Anti‐A1 was found in the serum of a patient of blood group A1 who had never received a blood transfusion. The patients serum caused agglutination of his own red blood cells. The anti‐A1 could be totally absorbed by red blood cells from the patient and from other A1 individuals. The anti‐A1 was inhibitable by soluble group A‐specific substance and was denatured by 2‐mercaptoethanol. The A and H serum transferases were normal. The presence of auto‐anti‐A1 in the serum of an A1 individual is yet another cause of ABO discrepancy.

Agglutination of red blood cells from patients with diabetes mellitus by a polyclonal human antibody specific for D-glucose.

Abstract. We have previously described an antibody which will agglutinate red blood cells which had been incubated in vitro in D‐glucose. This antibody is specific for the ring form of glucose, β‐D‐glucopyranose. The current report demonstrates that without prior in vitro incubation with glucose, red blood cells from 36 of 38 patients with diabetes mellitus, and 7 of 70 patients not diagnosed as diabetic were agglutinated by this antibody. Strength of agglutination of red blood cells from diabetic patients correlated with both glucose (r = 0.61; p<0.001) and hemoglobin A1c levels (r = 0.50; p<0.01) in simultaneously obtained samples. This reactivity could be reversed by incubating red blood cells from diabetics for several hours in saline. This report suggests that red blood cells from diabetic patients have membrane‐bound glucose that can be detected immunologically. Reversibility of the reaction and rapidity of in vitro glycosylation suggests short‐term binding of glucose. To our knowledge, this is the first report documenting immunological detection of in vivo short‐term reversible binding of glucose to cellular membranes.