IMMUNOBIOLOGY OF HUMAN-PREGNANCY - FOREWORD

This review focuses on immunologic aspects of normal human pregnancy a nd clinical reproductive abnormalities including preeclampsia, prematu re ovarian failure, endometriosis, and recurrent abortion. Recent rese arch advances in these fields and implications for clinical evaluation and therapy are discussed. In the opening section we evaluate pregnan cy as an altered immunologic state. Although the changes are subtle, a lterations in cellular and humoral immune responses have been describe d, and these are reviewed in some detail. In the second section, the u nique fetomaternal relationship in the human placental bed is describe d. Emphasized are new findings related to trophoblast cell biology, th e differentiation of these specialized cells at the maternal-fetal int erface, and their interactions with maternal immune cells. In particul ar, very recent investigations into the novel major histocompatibility complex (MHC) protein HLA-G are reviewed. Our emerging understanding of this key protein provides new insights into the mechanisms of accep tance of the fetal allograft. The third section of the review addresse s a common clinical disorder of pregnancy and focuses on the possible immunologic etiology of preeclampsia. This is a complex syndrome with multiple facets, yet strong evidence supports a role of immune dysfunc tion in its pathogenesis. The fourth section of the monograph deals wi th the immunologic aspects of infertility and reproductive failure in women. Three clinical conditions were selected for consideration: prem ature ovarian failure, endometriosis, and recurrent pregnancy loss. We summarize current information and evolving research related to the im munology of normal fertilization and pregnancy and pathophysiologic fe atures of reproductive failure. A critical evaluation of available tre atments for these conditions is provided. At present, immunotherapies are expensive, potentially dangerous, and largely without evidence-bas ed efficacy. Nevertheless, treatment options based on reproductive imm unologic concepts are becoming increasingly recommended to desperate c ouples seeking resolution of their reproductive failure. Overall, repr oductive immunology is in its infancy, a fact that is particularly tru e for the normal and abnormal physiology of human pregnancy. Neverthel ess, as immunologists become interested in pregnancy, and as reproduct ive biologists gain insights into specializations of the immune system that allow normal fertilization and placentation, a better understand ing of the fascinating interplay between these systems progresses stea dily. Fruitful clinical applications of our evolving knowledge surely will emerge in the near future.