Book Review

The Placenta and Neurodisability

Biology and Pathology of Trophoblast

N Engl J Med 2007; 356:96-97January 4, 2007

Article

The Placenta and Neurodisability
(Clinics in Developmental Medicine. No. 169.) Edited by Philip Baker and Colin Sibley. 153 pp., illustrated. London, Mac Keith Press, 2006. $75. ISBN: 978-1-898-68344-5

Biology and Pathology of Trophoblast
Edited by Ashley Moffett, Charlie Loke, and Anne McLaren. 272 pp., illustrated. New York, Cambridge University Press, 2006. $110. ISBN: 978-0-521-85165-7

For readers who are unaware of the marvels of the placenta — as a diagnostic tool, as a predictor of neonatal and adult morbidity, as an elegant and powerful system for studying the biology of cancer and immune tolerance, and simply as a fascinatingly cool organ — the book The Placenta and Neurodisability will rock their world.

One of the newest installments in the Clinics in Developmental Medicine series, the book evolved from meetings held in 1996 and 2003 for the purpose of discussing the relationship between the placenta and neonatal neuronal “disability.” (For the placental pathologist, the relationship between pathological findings and the neural outcome is key.) The chapter by Raymond Redline alone should convince readers of the value of placental pathology in predicting or explaining perinatal morbidity, especially neurologic disability. Redline carefully outlines such findings that are reliably associated with neurologic disability in a way that representatives of all medical disciplines will find insightful.

Japanese Ivory Carving of a Newborn in the State of Flexion with the Umbilical Cord and Placenta Attached.

All contributors to the book are truly “international experts at the forefront of their field,” as the editors state in the preface. All chapters provide summaries of many aspects of the placenta's function in fetal neurologic well-being, and the chapters on pathology and immunology are especially informative. Chapter 11 provides an excellent review of the entire book.

Readers who want a more scientific treatise on the wonders of the placenta should peruse Biology and Pathology of Trophoblast. In the thoroughly amusing introduction, Anne McLaren writes that the book was inspired by the realization that the “trophoblast as a tissue was shamefully neglected.” Charlie Loke, in the preface, recalls learning that other investigators at his institution had “an overlapping interest in trophoblast” but that, like him, they were “ignorant about the work being done by the others.” A meeting on trophoblast biology was convened, and a selection of the attendees contributed chapters to this book. (The chapters are interspersed with relatively unnecessary transcripts of discussions from the meeting that are relevant to the chapter topics.)

The standouts in this ambitious assembly are the chapters on placental immunology. Loke and Ashley Moffett, in their respective chapters, provide succinct yet comprehensive introductions to a number of important immunologic concepts pertinent to the process of placentation and the maintenance of pregnancy. Many interesting facts about placental immunology are shared. Examples include the role of danger signals and toll-receptor signaling in transmitting such danger signals, the “missing self” and “tunable threshold” models of the activation of natural killer (NK) cells in the process of placentation, and the possible involvement of tolerogenic dendritic cells in maintaining pregnancy. The authors also go into great detail about the possible role of NK cells in the process of placentation and maintenance of pregnancy, sometimes at the expense of discussing other areas of placental immunology, such as T regulatory cells (which have recently been of considerable interest in the literature). Although readers familiar with the immunologic literature will find the language accessible, at times these two chapters are overly reliant on jargon that the nonimmunologist may have trouble following. Nevertheless, these chapters are very effective at introducing a great deal of information and a number of difficult concepts; they also succeed in adapting the immunologic framework to fit the unique immunologic process of pregnancy.

Since The Placenta and Neurodisability is the more medically oriented of the two books, it suffers less from the inherent delays involved with publication. Biology and Pathology of Trophoblast, on the other hand, is already dated in some areas. For example, research in the preeclampsia field has been prolific and exciting recently, with a new understanding of the roles of soluble fms-like tyrosine kinase 1 (sFlt-1) and endoglin, neither of which is discussed in the book. In addition, the genetic basis of familial trophoblastic disease has been identified (NALP7), and the HLA-G gene has been shown to have a wider profile of expression than previously thought (not limited to the placenta). However, dated information is inevitable owing to the rapid progress in this field, and it does not detract from the book's value as a comprehensive introduction to trophoblast biology. The book offers tantalizing insight into a somewhat ignored area of reproductive biology that will probably whet the appetites of both young and seasoned investigators.

Drucilla J. Roberts, M.D.
Massachusetts General Hospital, Boston, MA 02114
djroberts@partners.org