The mammalian erythrocyte depends on a complex glycolytic mechanism for most of its energy. It is believed that this mechanism controls the transfer of cations across the cell membrane, and serves to maintain the biconcave shape of the red blood cell. Adenosine triphosphate and 2,3-diphosphoglycerate participate in the energy exchanges involved in these processes (1)(2)(3)(4)(5)(6)(7)(8)(9).Alterations in the relationship of the phosphate fractions develop in erythrocytes during storage (10-16). Similar changes do not occur with the senescence of erythrocytes in vivo (12). The deviations from the normal pattern may be reversed following the transfusion of stored blood (14), and by the addition of some of the purine nucleosides in vitro (17)(18)(19)(20)(21)(22)(23)(24) (31,32).The purpose of this study was to find out if the action of specific antibodies on fetal erythrocytes produces any alteration in the phosphate partitioning. The intra-erythrocytic phosphate pattern of normal fetal red cells was studied and compared with that of the red cells of adults.
MATERIAL AND METHODSAll the infants studied had been delivered normally but were otherwise unselected. There were ten female and six male babies in the normal group and nine females and one male with erythroblastosis fetalis. The average weight of the normal infants was 7.6 pounds (6.1 to 9.0), and the weight of the infants with hemolytic disease averaged 6.8 pounds (5.1 to 8.4). The blood group of one normal infant was A and that of the mother B.The blood group of two infants with hemolytic disease was AB and their mothers were A2 and B. The other infants were all products of homospecific pregnancies. The medication and anesthesia administered for delivery were similar in the two groups.The cord blood 1 of the normal babies was drawn aseptically from the umbilical vein at the time of delivery. The blood of the infants with hemolytic disease was obtained at the time of the first replacement transfusion within the first eight hours of life. All of the blood specimens were collected into acid-citrate-dextrose solution (ACD) formula A2 in the proportion of 100 ml. of blood to 15 ml. of preservative. The final concentration of glucose added was approximately 320 mg. per cent in whole blood. The specimens reached the laboratory within 30 minutes. Aliquots were distributed into sterile vacuum tubes. The chemical analysis of the fresh specimens was started immediately. The remaining aliquots were stored at 40 to 60 C. Mixing of the specimens during storage was avoided in order to duplicate the usual conditions under which "bank blood" is kept. Each specimen was cultured at the time of use, and the data were discarded if contamination was present.For studying the effect of antibodies added in vitro the plasma was removed from a portion of the blood specimen and replaced with sterile anti-D serum 3 and ACD solution. This mixture and the control specimen were incubated at 37 + 1°C in a water bath, and aliquots of each were distributed into sterile tubes for storage at 4...