Shaima M. Almasry, Rasha A. Elmansy, Amr K. Elfayomy and Samy A. Algaidi
Human anatomy and Emdryology, Taibah University, Medina, Saudi Arabia
This study aimed to evaluate the extent of remodeling of intra-decidual segments of decidual spiral arteries between 6th and 10th gestational weeks in women with unexplained recurrent miscarriages (RM) in comparison to gestational-matched controls. A possible association with the number, immunoexpressive behavior and ultrastructural changes of decidual natural killer cells (dNKCs) was investigated. Decidual biopsies were obtained from RM cases (n=40) and women with no history of spontaneous miscarriage (n=30). Staining was performed using PAS, anti-CD34 and anti-CD56 antibodies. The extent of decidual arterial remodeling was evaluated using a quantitative histological score and then related to the number of CD56+ dNKCs. In RM, dNKCs were distributed around the vessels and possessed numerous polyploidic protrusions on cell membranes crossing from one cell to another. The cells became more irregular and exhibited heterogeneous electron-dense granules in their cytoplasm compared to controls. The nonremodeling score and number of dNKCs were significantly increased in RM group (p< 0.001). The number of dNKCs was significantly correlated with the scores in both control (r=0.491; p=0.006) and RM (r=0.852; p < 0.001) groups. We concluded that, dNKCs could play a key role in impaired decidual arterial remodeling involved in early RM. This may be due to increased numbers of dNKCs or impaired cellular interactions resulting from alterations of the ultrastructure.