Maternal-fetal transfer of immunoglobulins.

OBJECTIVE: The goal of this review is to summarize the current knowledge about the transfer of immunoglobulins from the mother to the fetus. Data obtained experimentally and clinically will be discussed, and intervention trials and options will be examined.

DATA SOURCE: References are limited to the English language and to human data. Sources include computerized databases and bibliographies of recent articles and books.

RESULTS: Electronmicroscopic studies have unveiled the passage route of IgG through the placenta. The placental in vitro perfusion system has become a valuable experimental model, with a crucial role in the preclinical evaluation of trials to manipulate the maternal-fetal passage of immunoglobulins.

CONCLUSIONS: Immunoglobulins are transferred through the placenta in an active, selective and affinity-restricted process, which is Fc-gamma receptor mediated and intracellular. Much work is still required to improve our ability to control the rate and the efficiency of this process, but the results of pioneering attempts have been encouraging.