Passive Transfer of Immunity

Abstract

Although mammalian fetuses are generally capable of antibody synthesis well before birth, little antibody is in fact produced. This is doubtless due partly to depression of the immune response by various immuno suppressive measures (p. 134). However, it stems also from the fact that the fetus is protected from exposure to foreign antigens (other than those of the mother herself). After birth, this is no longer the case, and the newborn mammal is suddenly and simultaneously exposed to a wide spectrum of microorganisms, many of them pathogenic. An immunologically naïve animal, possibly with some residual depression of its capacity to respond, would be extremely vulnerable to this onslaught.