Maternofetal Transfusion During Delivery and Rh-Sensitisation of the Newborn

Fetal Human Hemolytic Plaque-Forming Cells

“…PFC against maternal and other erythrocyte antigens were commonly detected in human fetal liver, lymph nodes, spleen, or thymus as early as 16 weeks gestation and were usually more abundant in liver than in spleen after 16 weeks gestation. These data corroborate studies from other laboratories which indicate that human fetuses develop some forms of immunocompétence very early during gestation.positive mother [1,6], but there is little evidence to this effect.Hemolytic plaque-forming cells (PFC) reactive against a variety of natural and synthetic erythrocyte epitopes have been de scribed in both immunized and nonimmunized individuals in numerous species [3,4,8,13,14], Sensitive methods for enumer ating individual PFC [8], each producing a particular class of immunoglobulin [20] have served to delineate early events in the immune response to erythrocyte-bound anti gens [12], Methods developed in animal models, and used recently [8,12,20] to detect PFC among maternal peripheral blood leukocytes [9,11] were employed in this investigation to survey fetal and neonatal tis sues for immunocompetent cells directed against various erythrocyte-bound epitopes. …”

“…Future studies should be di rected at determining whether PFC reacting against MRC appear more often in ABO and in Rh incompatible pregnancies than in fetuses compatible with their mothers. It may well be relevant to the problem of apparently spontaneous anti-Rh activity in Rh-negative individuals [6] that reactivity to maternal red cell antigens can exist be fore birth. Evidence that such antenatal re activity could be due to the Rh(D) antigens remains, however, to be determined.…”

“…Although maternal reactivity to certain antigens of a fetus has been well docu mented [1], evidence of fetal sensitization to maternal antigens is sparse [6,18] de spite data documenting passage of macro molecules from mother to fetus either dur ing gestation or at parturition [5], It might be expected a priori that a fetus should either be too immature to have reactivity against maternal antigens or that it might be rendered tolerant to them.…”

An Example of a Naturally Occurring Anti-cE (Rh27) that Binds Complement

“…has had no known exposure to red blood cells. It has been sug gested that exposure to maternal red blood cells during delivery may serve as a primary red blood cell antigen immunization [5], Since A.K. 's mother and only brother are deceased, there is no way to determine if his mother's red blood cells were Rh:27 and…”

Naturally Occurring Anti-D, Anti-K, Anti-Fy^a, and Anti-Le^ab

“…With reference to naturally occurring an ti-D, in 1973, Hindeman [1] affirmed that D-positive red cells passing through the placenta were able to sensitize a D-negative fetus. These findings were later confirmed by some gropus and rejected by others [2,3].…”