Macrophages and apoptotic cell clearance during pregnancy.

Background: During implantation, apoptosis is critical for the appropriate tissue remodeling of the maternal decidua and invasion of the developing embryo, yet the regulation of apoptosis is also imperative for a successful pregnancy. The quick and effective removal of apoptotic cells by tissue macrophages represents an essential process, which prevents the release of self-antigens, and in the case of pregnancy, paternal alloantigens.

Methods Of Study: Recent studies have shown that the process of apoptotic cell clearance is not a neutral event, but rather an active one that induces macrophage production of anti-inflammatory cytokines and survival factors.

Epithelial ovarian cancer cells secrete functional Fas ligand.

The Fas/Fas ligand (FasL) system has been suggested to play an important role in the establishment of an immune privilege status of the tumor by inducing Fas-mediated apoptosis in tumor-specific lymphocytes. However, the role of cell surface-expressed FasL in tumor cell protection has recently become controversial. In this study, we have demonstrated that ascites-derived epithelial ovarian cancer cells lack membranal FasL but constitutively secrete whole, intracellular FasL (37 kDa) via the release of microvesicles.

The Fas/FasL system in reproduction: survival and apoptosis.

For centuries, the question of "whether there is life after death" has intrigued the mind of philosophers, and the same question fascinates researchers in the field of apoptosis today. The death of a cell is by no means the end of the story. On the contrary, growing evidence suggests that the clearance of apoptotic bodies by macrophages is an important regulatory component in tissue renewal.

Role of the Fas/Fas ligand system in female reproductive organs: survival and apoptosis.

For centuries, the question of "whether there is life after death" has intrigued the mind of philosophers and the same question fascinates researchers in the field of apoptosis today. The death of a cell is by no means the end of the story. On the contrary, growing evidence suggests that the clearance of apoptotic bodies by macrophages is an important regulatory component in tissue renewal.

Differential regulation and function of the Fas/Fas ligand system in human trophoblast cells.

Trophoblast rejection, which is characterized by increased apoptosis, is mediated by T helper (Th)-1, or proinflammatory, cytokines, whereas Th-2, or anti-inflammatory, cytokines confer immune protection and facilitate implantation. We investigated the role of both types of cytokines on the expression and function of the Fas/Fas ligand (FasL) apoptotic pathway in trophoblast cells. First-trimester human trophoblast primary-culture cells as well as A3 and HTR/8 trophoblast cell lines were treated with proinflammatory cytokines such as interferon-gamma (IFN-gamma) and tumor necrosis factor alpha (TNFalpha) and with the anti-inflammatory cytokines interleukin (IL)-6 and IL-10.