Regular articleBiomarkers, genomics, proteomics, and gene regulationReduced Stathmin-1 Expression in Natural Killer Cells Associated with Spontaneous Abortion

Female CBA/J mice impregnated by male DBA/2J mice (CBA/J×DBA/2J matings) are prone to spontaneous abortion, although the reason for this is unclear. In this study, the stathmin-1 expression pattern was evaluated in uterine natural killer (uNK) cells purified from CBA/J×DBA/2J matings. Results were compared with those in a CBA/J×BALB/c control group that yields successful pregnancies. The mean ± SD percentage of stathmin-1+ cells in the CD49b+ uNK cell population was lower in CBA/J×DBA/2J mice (0.7% ± 0.4%) than in control CBA/J×BALB/c mice (4.9% ± 1.5%, P < 0.01) using flow cytometry, and the intracellular stathmin-1 level in uNK cells was lower in CBA/J×DBA/2J mice than in control mice using Western blot analysis. Co-localization of lectin from Dolichos biflorus agglutinin (DBA-lectin) and stathmin-1 was confirmed using multivision immunohistochemical analysis. The frequency of stathmin-1+DBA-lectin+ cells was lower in CBA/J×DBA/2J mice than in CBA/J×BALB/c mice. A similar trend in the frequency of stathmin-1+CD56+ cells was seen in patients with unexplained spontaneous abortion compared with normal early pregnancy. A neutralizing antibody against stathmin-1 further increased the percentage of embryo loss in CBA/J×DBA/2J matings. These results provide evidence that stathmin-1 expression in uNK cells at the maternal-fetal interface may help modulate uNK cell function and may be beneficial for a successful pregnancy.