Human decidual stromal cells secrete soluble pro-apoptotic factors during decidualization in a cAMP-dependent manner.

STUDY QUESTION: Is there a relationship between decidualization and apoptosis of decidual stromal cells (DSC)? SUMMARY ANSWER: Decidualization triggers the secretion of soluble factors that induce apoptosis in DSC. WHAT IS KNOWN ALREADY: The differentiation and apoptosis of DSC during decidualization of the receptive decidua are crucial processes for the controlled invasion of trophoblasts in normal pregnancy. Most DSC regress in a time-dependent manner, and their removal is important to provide space for the embryo to grow. However, the mechanism that controls DSC death is poorly understood. STUDY DESIGN, SIZE, DURATION: The apoptotic response of DSC was analyzed after exposure to different exogenous agents and during decidualization. The apoptotic potential of decidualized DSC supernatants and prolactin (PRL) was also evaluated. PARTICIPANTS/MATERIALS, SETTING, METHODS: DSC lines were established from samples of decidua from first trimester pregnancies. Apoptosis was assayed by flow cytometry. PRL production, as a marker of decidualization, was determined by enzyme-linked immunosorbent assay. MAIN RESULTS AND THE ROLE OF CHANCE: DSCs were resistant to a variety of apoptosis-inducing substances. Nevertheless, DSC underwent apoptosis during decidualization in culture, with cAMP being essential for both apoptosis and differentiation. In addition, culture supernatants from decidualized DSC induced apoptosis in undifferentiated DSC, although paradoxically these supernatants decreased the spontaneous apoptosis of decidual lymphocytes. Exogenously added PRL did not induce apoptosis in DSC and an antibody that neutralized the PRL receptor did not decrease the apoptosis induced by supernatants. LIMITATIONS, REASONS FOR CAUTIONS: Further studies are needed to examine the involvement of other soluble factors secreted by decidualized DSC in the induction of apoptosis. WIDER IMPLICATIONS OF THE FINDINGS: The present results indicate that apoptosis of DSC occurs in parallel to differentiation, in response to decidualization signals, with soluble factors secreted by decidualized DSC being responsible for triggering cell death. These studies are relevant in the understanding of how the regression of decidua, a crucial process for successful pregnancy, takes place. STUDY FUNDING/COMPETING INTERESTS: This work was supported by the Consejería de Economía, Innovación y Ciencia, Junta de Andalucía (Grant CTS-6183, Proyectos de Investigación de Excelencia 2010 to C.R.-R.) and the Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Spain (Grants PS09/00339 and PI12/01085 to E.G.O.). E.L.-D. was supported by fellowships from the Ministerio de Educación y Ciencia, Spain and the University of Granada. The authors have no conflict of interest.

Human decidual stromal cells secrete C-X-C motif chemokine 13, express B cell-activating factor and rescue B lymphocytes from apoptosis: distinctive characteristics of follicular dendritic cells.

BACKGROUND: Decidual stromal cells (DSCs) have classically been considered fibroblastic cells, although their function, cell lineage and origin are not fully understood. We previously demonstrated that human DSCs showed similarities with follicular dendritic cells (FDCs): DSCs expressed FDC-associated antigens, both types of cells are contractile and both are related to mesenchymal stem cells (MSCs). To further characterize DSCs, we investigated whether DSCs and FDCs share any distinctive phenotypical and functional characteristics. METHODS: Human FDC lines were obtained from tonsillectomy samples, human DSC lines from elective termination of pregnancy samples and human MSC lines from bone marrow aspirates. We isolated DSC, FDC and MSC lines and compared their characteristics with flow cytometry and enzyme-linked immunosorbent assay. Cell lines were cultured with tumour necrosis factor (TNF) and lymphotoxin (LT)α(1)ß(2), cytokines involved in FDC differentiation. Cell lines were also differentiated in culture after exposure to progesterone and cAMP, factors involved in the differentiation (decidualization) of DSC. RESULTS: Like MSCs, DSCs and FDCs expressed MSC-associated antigens (CD10, CD29, CD54, CD73, CD106, α-smooth muscle actin and STRO-1) and lacked CD45 expression, and all three types of cell line showed increased expression of CD54 (ICAM-1) and CD106 (VCAM-1) when cultured TNF and LTα(1)ß(2). DSCs and FDCs, however, exhibited characteristics not observed in MSCs: DSCs expressed FDC-associated antigens CD14, CD21 and CD23, B cell-activating factor and secreted C-X-C motif chemokine 13. Moreover, DSC lines but not MSC lines inhibited the spontaneous apoptosis of B lymphocytes, a typical functional attribute of FDC. During culture with progesterone and cAMP, FDCs, like DSCs but in contrast to MSCs, changed their morphology from a fibroblastic to a rounder shape, and cells secreted prolactin. CONCLUSIONS: Our results suggest that DSCs and FDCs share a common precursor in MSCs but this precursor acquires new capacities when it homes to peripheral tissues. We discuss these shared properties in the context of immune-endocrine regulation during pregnancy.

[Evaluation of antibiotic prophylaxis in surgery]. / Evaluación de la profilaxis antibiótica en cirugía.

OBJECTIVE: To evaluate the level of compliance with antibiotic prophylaxis during surgery in a university referral hospital. PATIENTS AND METHODS: A descriptive study of 257 patients undergoing clean or clean-contaminated elective surgery was carried out in 2001. Data were gathered prospectively by three anesthesiologists in the operating room. Prophylaxis was considered to have been administered correctly if the first dose was given before the skin incision, if a second dose was given during operations lasting longer than 240 minutes, and if the antibiotic prescribed was of a wide enough spectrum to cover the type of surgical procedure performed. RESULTS: Prophylaxis was administered incorrectly to 132 patients (51.4%). The causes were administration after incision in 21.8%, long-duration surgery without a second dose in 15.6%, administration after incision plus long-duration surgery without a second dose in 3.1%, inadequate-spectrum antibiotic in 4.7%, administration after incision plus inadequate dose in 2.7%, inadequate dose in 1.9%, inadequate-spectrum antibiotic plus administration after incision in 0.8%, late second dose in 0.4%, long-duration surgery without a second dose plus inadequate dose in 0.4%. DISCUSSION: The rates of late administration of an antibiotic or failure to administer a second dose during long-duration surgery is high. CONCLUSION: To improve the low level of compliance and avoid late administration of antibiotics, we propose that the anesthetist be responsible for giving antibiotic prophylaxis and for directly monitoring compliance errors in the operating room.

[Anesthetic management of a hydatid cyst adhering to the inferior vena cava]. / Tratamiento anestésico de un quiste hidatídico adosado a la vena cava inferior.

A patient with a hepatic hydatid cyst with fistula formation to inferior vena cava is reported. To carry out the resection, the cyst was isolated from systemic circulation by means of cardiopulmonary bypass. Inferior vena cava was cannulated through the right atrium until the implantation area of the cyst (above the hepatic veins) was surpassed. Bypass was carried out in 25 minutes by means of cannulation of the ascending aorta, without clamping the aorta, myocardial protection or hypothermia. Postoperative analgesia was achieved with a lumbar epidural catheter. Measures to prevent anaphylactic shock are recommended, an anesthetic technique based on the prevention of hypersensitivity reactions and a careful surgical technique to prevent hydatid dissemination.

Apoptotic DC-SIGN+ cells in normal human decidua.

BACKGROUND: Normal pregnancy and spontaneous abortion in humans and mice are associated with immune responses. The decidua harbors dendritic cells identifiable in humans by their expression of DC-SIGN. Because dendritic cells are essential for immune response regulation, decidual DC-SIGN+ cells may play a role in normal or pathological pregnancy outcomes. Previous reports suggested that DC interact with NK cells in decidua, although the functional significance of this phenomenon remains unknown. OBJECTIVE: We studied the presence of conjugates of DC-SIGN+ cells with CD56+ NK cells in normal human decidua. METHODS: Conjugates of DC-SIGN+ cells with CD56+ NK cells were studied in leukocyte suspensions of normal human decidua (6-11 weeks) by flow cytometry and confocal microscopy. The presence of apoptotic cells was determined by the TUNEL assay, incubation with annexin V and confocal microscopy in decidual leukocyte suspensions and by the TUNEL assay in decidual sections. RESULTS: We observed conjugates of decidual DC-SIGN+ cells with CD56+ NK cells (40.2±26.1% of all the DC-SIGN+ cells by flow cytometry and 52.3±10.2% by confocal microscopy). We also found that a proportion of DC-SIGN+ cells were in apoptosis, since they were TUNEL+ (40.2±7.2% of all DC-SIGN+ cells in decidual sections) and annexin V+ (34.4±15.2% in leukocyte suspensions). And sorted DC-SIGN+ cells had multilobulated nuclei. CONCLUSIONS: The conjugates of decidual DC-SIGN+ cells with CD56+ NK cells strongly suggest that these latter cells induce apoptosis in DC-SIGN+ cells during normal pregnancy. We discuss this possibility in the context of maternal-fetal tolerance.

Reduced proportion of decidual DC-SIGN+ cells in human spontaneous abortion.

Recent studies showed that some functions of decidual dendritic cells appear to be essential for pregnancy. In humans, decidual dendritic cells are identifiable by their expression of DC-SIGN. We compared the subpopulations of human decidual DC-SIGN+ cells from first-trimester normal pregnancies and spontaneous abortions by flow cytometry. In normal decidua, DC-SIGN+ cells expressed antigens associated with immature myeloid dendritic cells. In samples from spontaneous abortions, we detected decidual DC-SIGN+ cells with an antigen phenotype equivalent to that of DC-SIGN+ cells from normal pregnancies, but at a significantly lower proportion (P < 0.01). Our results support the hypothesis that dendritic cells play a role in normal or pathological human pregnancy outcomes.