Preeclampsia and the role of uterine natural killer cells

Abstract

The investigation of preeclampsia has been greatly facilitated by the use of pregnant mouse models. In this study, immunodeficient mice (RAG2"/yc") were used to examine the migration of white blood cells (WBC) and uterine Natural Killer cells to the uterus and spleens of bone marrow engrafted mice. Three weeks after the mice were injected with C57B16 or Balbc bone marrow cells, they were mated. Ten days after the appearance of a copulation plug, organs were collected, paraffin embedded and sectioned. Hematoxylin and Eosin (H&E) staining was done to determine basic morphology and confirm successful sectioning technique. Biotinylated anti-CD45 antibody was used to determine the presence of WBC. Dolichos Biflorus Agglutinin (DBA) lectin was used to determine the presence of uterine Natural Killer (uNK) cells. Neither anti-CD45 nor DBA stain yielded significant positive results for the test mice. Currently, there is no other leukocyte-specific antibody available to stain WBC paraffin-embedded sections. Periodic Acid Schiff (PAS) staining for Natural Killer cells showed 2-4/100x field of view in control mice, and 7 of 12 of the spleens from tested mice had at least one positive cell, which 4 had levels similar to controls. Follicles were presented in most of the positive control mouse spleen sections but not in the test mice. While serum antibody was previously demonstrated in these mice, we found only low numbers of transplanted bone marrow cells in the spleen or uterus of these mice. It appears that engraftment will not be successful in RAG2"/yc" mice in the absence of further immunosuppressive treatment.