IMMUNOLOCALIZATION OF TUMOR-NECROSIS-FACTOR-ALPHA (TNF-ALPHA) IN THE PLACENTAL BED OF NORMOTENSIVE AND HYPERTENSIVE HUMAN PREGNANCIES

To identify tumour necrosis factor (TNF)-alpha immunopositive cells, t hird trimester human placental bed biopsies were selected from nine no rmotensive control women, 16 severely pre-eclamptic patients and seven patients with pre-existing hypertension with superimposed pre-eclamps ia. In addition, five first and early second trimester specimens were included in the study. Immunostaining was performed with a mouse IgG1 monoclonal antibody (J1D9) reactive specifically with human TNF-alpha (1:300 ascitic fluid), using a biotin-streptavidin-peroxidase techniqu e. Variable staining of stromal cells was noted in all biopsies. Speci mens of early pregnancy showed marked immunostaining for TNF-alpha on proliferating tips of anchoring villi, invasive interstitial cytotroph oblast (but not the multinuclear giant cells), and endovascular tropho blast invading the spiral arteries. At term, weak staining was found i n trophoblast incorporated within spiral artery walls. In biopsies fro m pre-eclamptic patients, spiral arteries without physiological change showed very little staining except in atherotic vessels where the inf iltrated lipophages often showed intense immunolabelling. The marked p resence of TNF-alpha in extravillous cytotrophoblast of young specimen s is suggestive of a role in early invasion. Immunostaining of foam ce lls in non-invaded spiral arteries in pre-eclampsia at or near-term in dicates a potential role of this cytokine in the development of athero tic lesions. (C) 1998 W. B. Saunders Company Ltd.