We evaluated the role of calpain in human sperm for fertilization.

Semen collected manually from healthy donors with informed consent was liquefied and following percoll gradient centrifugation. After exposure to different concentration of progesterone(P)or under hypoxic condition(H), the samples were used for immunostaining, SDS-PAGE and western blot analysis. The increase of calcium ion concentration in the sperm was observed by fluorescent microscope(ARGUS-50CA)system using Fura 2-AM. The role of calpain for fertilization was speculated from the results of Hamster penetration test, Hamilton Motility Analyzer, Triple satin method and Acrobeads test using calpain inhibitors.

Immunostaining in human sperm was observed using antibodies against theμ-calpain in the types of whole acrosome, equatorial segment, head segment, neck segment or neck and tail segment. Most of these demonstrated acrosome type staining with anti-proμ-calpain antibody. Western blot analysis revealed P or H treatment to cause a concentration or time-dependent activation ofμ-calpain.

In addition, calpain inhibitors significantly reduced the acrosome reaction and penetration.

The results suggest thatμ-calpain in human sperm plays an important role for the fertilization

Innate immunity plays an important role in reproduction. Particularly, dendritic cells (DCs) and invariant natural killer T (iNKT) cells are seemed to be the important players for the onset of miscarriage and preterm birth in murine and human pregnancy. In this review, the characteristic features and functions of these cells in fetomaternal immunity and their contributions to the onset of miscarriage and preterm birth are discussed. These insights on innate immune system function in reproduction may provide new perspectives for understanding the etiology of pregnancy complications.

Preeclampsia is one of the placenta-mediated pregnancy complications, which includes fetal growth restriction (FGR), late pregnancy loss, or placental abruption. Severe pregnancy complications are related with abnormalities of placentas. In preeclampsia, two stage disorder theory has been proposed for the pathophysiology of preeclampsia: poor placentation is occurred at the first step followed with the systemic endothelial dysfunction at the second step. We, so far, have been focused on the role of autophagy for placentation to clarify the mechanism of development of preeclampsia. The inhibition of autophagy was mediated with the failure of functions, invasion and vascular remodeling, in extravillous trophoblasts (EVTs). In addition, placenta-specific atg7 knockout mice, in which autophagy was impaired in trophoblasts, showed growth restriction in placentas and high blood pressure in dams. On the other hand, neither proteinuria in dams nor FGR were seen in the mice. Taken together, impairment of autophagy was mainly mediated with the first step, but not the second step. Recently, we obtained some new findings related with the protein aggregation by autophagy inhibition, as can be seen in neurodegenerative diseases. In this paper, we review the role of autophagy in preeclampsia.

Macrophages (MΦs) are involved in folliculogenesis. However, it is unknown which type of MΦ, M1 or M2, plays a more essential role in the ovary. To investigate the role of macrophage in subtype level in folliculogenesis, CD206 or CD11c diphtheria toxin receptor transgenic (DTR) mice, which enable depletion of CD206+ M2 MΦs and CD11c+ MΦ or CD11c+ Dendritic cells (DCs), respectively, were used. In wild type mice (WT), the proportion of CD206+ M2 MΦs was not increased in follicular induction, while that of CD11c+ M1 MΦs was increased. In CD206 DTR mice, folliculogenesis was normal. In CD11c DTR mice, folliculogenesis was impaired with ovarian hemorrhage and the staining of platelet derived growth factor-receptor β (PDGF-Rβ), a marker of pericytes, and CD34, a marker of endothelial cells, was reduced. CD11c+ cells, M1 MΦs or DCs, may be involved in folliculogenesis, while M2 MΦs are not involved in folliculogenesis.