Dendritische Zellen bei der Intra- und Extrauteringravidität : mögliche Bedeutung für die feto-maternale Toleranz

Dendritic cells (DC) are potent antigen-presenting cells. They are able to induce immunity on the one hand, on the other hand DC play a central role in the induction of peripheral tolerance. The presence of different maturation states of DC has been described at the feto-maternal implantation site of intrauterine pregnancies (IUP). It is assumed that the interaction of immature DC with natural killer (NK)-cells plays an important role for the induction and maintenance of feto-maternal tolerance. Mature DC are characterized to exhibit protective features but they might also be responsible for the development of intrauterine abortions by inducing a T-cell mediated immune response. Tubal pregnancies (TP) provide an important comparison: while the presence of mature and immature DC in IUP has been stated by several studies, there is little known about the presence of these cells in the extrauterine implantation site of TP. The TP is characterized by a different invasive behaviour of trophoblast cells and a different pattern of immune cells (e.g. absence of NK-cells). In this study for the first time the pattern of mature and immature DC at the implantation site of TP was analysed and compared to the pattern in the IUP. A differentiation was made between viable tubal pregnancies (VTP) and tubal abortions (TA). We examined seven specimens of decidual tissue obtained from women with intact IUP undergoing abortion in the 5.-9. week of gestation, ten specimens of VTP (identified by colour Doppler sonography) and five specimens of TA. VTP and TA were of the same gestational age as the IUP. Immunohistochemical staining protocols were established on paraffin sections. The following surface markers were examined on serial sections: 1. Cytokeratin 7 (identification of implantation site), 2. CD83 (mature DC), 3. DEC205 (immature, activated DC), 4. DC-SIGN (immature, macrophage-like transient state of DC), 5. CD14 (identifies monocytes/macrophages). For CD14 single labelling was performed as well as for some specimens double ...