1. Placental Complement Activation in Fetal and Neonatal Alloimmune Thrombocytopenia: An Observational Study
- Author
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Leendert Porcelijn, Leendert A. Trouw, Dick Oepkes, Gestur Vidarsson, Hans J. Baelde, Enrico Lopriore, Marie-Louise P. van der Hoorn, Kyra L. Dijkstra, Carin van der Keur, C. Ellen van der Schoot, Dian Winkelhorst, Thijs W de Vos, Peter G. J. Nikkels, Masja de Haas, Rick Kapur, Lotte E van der Meeren, Michael Eikmans, Rianne D M van Bergen, Manon Bos, Clinical Haematology, and AII - Inflammatory diseases
- Subjects
Male ,Placenta ,placental dysfunction ,030204 cardiovascular system & hematology ,fetal growth restriction ,0302 clinical medicine ,Pregnancy ,Biology (General) ,Complement Activation ,Spectroscopy ,030219 obstetrics & reproductive medicine ,biology ,Obstetrics ,Communication ,Immunoglobulins, Intravenous ,General Medicine ,Computer Science Applications ,Chemistry ,medicine.anatomical_structure ,Neonatal alloimmune thrombocytopenia ,Female ,Antibody ,Adult ,medicine.medical_specialty ,QH301-705.5 ,Catalysis ,Antibodies ,Inorganic Chemistry ,03 medical and health sciences ,Syncytiotrophoblast ,Fetus ,Antigen ,medicine ,Humans ,Physical and Theoretical Chemistry ,QD1-999 ,Molecular Biology ,Retrospective Studies ,placentaldysfunction ,business.industry ,Organic Chemistry ,Histocompatibility Antigens Class I ,Infant, Newborn ,fetal neonatal alloimmune thrombocytopenia ,medicine.disease ,alloimmunization during pregnancy ,Thrombocytopenia, Neonatal Alloimmune ,histopathology placenta ,Case-Control Studies ,biology.protein ,Histopathology ,business ,classical pathway complement activation ,Villitis of unknown etiology - Abstract
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a disease that causes thrombocytopenia and a risk of bleeding in the (unborn) child that result from maternal alloantibodies directed against fetal, paternally inherited, human platelet antigens (HPA). It is hypothesized that these alloantibodies can also bind to the placenta, causing placental damage. This study aims to explore signs of antibody-mediated placental damage in FNAIT. We performed a retrospective study that included pregnant women, their newborns, and placentas. It comprised 23 FNAIT cases, of which nine were newly diagnosed (14 samples) and 14 were antenatally treated with intravenous immune globulins (IVIg) (21 samples), and 20 controls, of which 10 had anti-HLA-class I antibodies. Clinical information was collected from medical records. Placental samples were stained for complement activation markers (C1q, C4d, SC5b-9, and mannose-binding lectin) using immunohistochemistry. Histopathology was examined according to the Amsterdam criteria. A higher degree of C4d deposition was present in the newly diagnosed FNAIT cases (10/14 samples), as compared to the IVIg-treated FNAIT cases (2/21 samples, p = 0.002) and anti-HLA-negative controls (3/20 samples, p = 0.006). A histopathological examination showed delayed maturation in four (44%) placentas in the newly diagnosed FNAIT cases, five (36%) in the IVIg-treated FNAIT cases, and one in the controls (NS). C4d deposition at the syncytiotrophoblast was present in combination with low-grade villitis of unknown etiology in three newly diagnosed FNAIT cases that were born SGA. We conclude that a higher degree of classical pathway-induced complement activation is present in placentas from pregnancies with untreated FNAIT. This may affect placental function and fetal growth.
- Published
- 2021