Uncomplicated Oocyte Donation Research Articles

Uncomplicated oocyte donation pregnancies display an elevated CD163-positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA mismatches.

ProblemThe embryo of an oocyte donation (OD) pregnancy is completely allogeneic to the mother, which may challenge the maternal immune system to tolerize the fetus. Decidual macrophages are essential in maintaining a healthy pregnancy, and type 2 macrophages may exhibit immune suppressive activity. We hypothesized that the composition of decidual macrophages is different between uncomplicated OD pregnancies and non‐OD in vitro fertilization (IVF) pregnancies, and is related to fetal‐maternal incompatibility.Method of studyWomen with uncomplicated pregnancy were enrolled: 25 singleton OD pregnancies and 17 non‐OD IVF pregnancies. The extent of immunohistochemical staining of CD14 (pan‐macrophage marker) and CD163 (type 2 macrophage marker) in both decidua basalis and parietalis was quantitated by digital image analysis. Maternal and fetal DNA was typed for human leukocyte antigen (HLA)‐A, ‐B, C, ‐DRB1, and ‐DQB1, and fetal‐maternal HLA mismatches were calculated.ResultsOD pregnancies showed a higher percentage of CD163+ staining (P = .040) and higher CD163/CD14 ratio (P = .032) in the parietalis than non‐OD IVF. The OD group was separated into a semi‐allogeneic group (≤5 fetal maternal HLA mismatches) and a fully allogeneic group (> 5 mismatches). The HLA‐fully‐allogeneic OD group, but not the HLA‐semi‐allogeneic OD group, showed significantly elevated CD163/CD14 ratio in the parietalis compared with the non‐OD IVF group (P < .05).ConclusionsUncomplicated OD pregnancies display a higher CD163‐positive cell fraction in the total decidual macrophage population compared to autologous pregnancies, which may suggest that a local type 2 macrophage‐related mechanism is needed to compensate for the higher fetal‐maternal HLA mismatch load.

Uncomplicated oocyte donation pregnancies display elevated CD163 positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA mismatches

Uncomplicated oocyte donation pregnancies display elevated CD163 positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA mismatches

P–420 uncomplicated oocyte donation pregnancies display elevated CD163 positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA class II mismatches

Abstract Study question Do quantity and composition of decidual macrophages differ between uncomplicated oocyte donation (OD) pregnancies and non-OD in vitro fertilization (IVF) pregnancies? Summary answer OD placentas show higher decidual CD163 positive fraction within the total macrophage population compared to non-OD IVF placentas. What is known already The embryo of an OD pregnancy is completely allogeneic to the mother, which may lead to a bigger challenge for the maternal immune system to tolerize the fetus compared to autologous pregnancies. Placental macrophages may be essential in maintaining a healthy pregnancy. Macrophages can be classified into different categories based on phenotype and characteristics, in which type 2 macrophages are thought to exhibit immune suppressive activity. Study design, size, duration This retrospective case-control study included patients who delivered in the Leiden University Medical Center between January 1st 2006 and July 1st 2016. A total of 42 pregnancies were enrolled in this study, conceived by uncomplicated singleton OD pregnancies (n = 25) or non-OD IVF pregnancies (n = 17). Medical records were reviewed and clinical data were collected. Placental tissue samples were collected for immunohistochemical staining and blood samples were collected for HLA typing. Participants/materials, setting, methods Placentas were collected and immunohistochemically stained for CD14 (pan-macrophage marker) and CD163 (type 2 macrophage marker). The extent of staining was quantitated by digital image analysis software. To assess mismatching, maternal and fetal DNA was typed for HLA-A, -B, C, -DRB1, and -DQB1. Main results and the role of chance A significantly lower percentage of CD14 positive staining was observed in the decidua basalis of OD pregnancies compared to non-OD IVF pregnancies (p = 0.030). Consequently, the CD163/CD14 ratio in OD group was higher than in non-OD IVF group (p = 0.243). In the parietalis, OD pregnancies demonstrated a significantly higher percentage of CD163+ staining (p = 0.040) and a significantly higher CD163/CD14 ratio (p = 0.032) compared to non-OD IVF group. The reproducibility of this quantitative analysis was found to be high. OD group was separated into a syngeneic group (number of mismatches lower than half of the antigens per HLA locus) and an allogeneic group (number of mismatches higher than half of the antigens per HLA locus). Significant differences of CD163+ and CD163/CD14 ratio were found in the decidua parietalis when comparing the HLA-classII-allogeneic OD group with the non-OD IVF group (p = 0.047). This difference was not found for the HLA-class-II-syngeneic OD group. Limitations, reasons for caution Our study only focused on decidua basalis and parietalis, no other locations in the placentas. Larger sample size might be needed to verify the association between macrophages and HLA mismatches. Wider implications of the findings: To our knowledge, this study is the first to quantify a higher CD163 positive M2 macrophages load within the total decidual macrophages of uncomplicated OD pregnancy compared to non-OD IVF pregnancies. Trial registration number Not applicable

P-420 Pre-selected for an award: Uncomplicated oocyte donation pregnancies display elevated CD163 positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA class II mismatches

Abstract Study question Do quantity and composition of decidual macrophages differ between uncomplicated oocyte donation (OD) pregnancies and non-OD in vitro fertilization (IVF) pregnancies? Summary answer OD placentas show higher decidual CD163 positive fraction within the total macrophage population compared to non-OD IVF placentas. What is known already The embryo of an OD pregnancy is completely allogeneic to the mother, which may lead to a bigger challenge for the maternal immune system to tolerize the fetus compared to autologous pregnancies. Placental macrophages may be essential in maintaining a healthy pregnancy. Macrophages can be classified into different categories based on phenotype and characteristics, in which type 2 macrophages are thought to exhibit immune suppressive activity. Study design, size, duration This retrospective case-control study included patients who delivered in the Leiden University Medical Center between January 1st 2006 and July 1st 2016. A total of 42 pregnancies were enrolled in this study, conceived by uncomplicated singleton OD pregnancies (n = 25) or non-OD IVF pregnancies (n = 17). Medical records were reviewed and clinical data were collected. Placental tissue samples were collected for immunohistochemical staining and blood samples were collected for HLA typing. Participants/materials, setting, methods Placentas were collected and immunohistochemically stained for CD14 (pan-macrophage marker) and CD163 (type 2 macrophage marker). The extent of staining was quantitated by digital image analysis software. To assess mismatching, maternal and fetal DNA was typed for HLA-A, -B, C, -DRB1, and -DQB1. Main results and the role of chance A significantly lower percentage of CD14 positive staining was observed in the decidua basalis of OD pregnancies compared to non-OD IVF pregnancies (p = 0.030). Consequently, the CD163/CD14 ratio in OD group was higher than in non-OD IVF group (p = 0.243). In the parietalis, OD pregnancies demonstrated a significantly higher percentage of CD163+ staining (p = 0.040) and a significantly higher CD163/CD14 ratio (p = 0.032) compared to non-OD IVF group. The reproducibility of this quantitative analysis was found to be high. OD group was separated into a syngeneic group (number of mismatches lower than half of the antigens per HLA locus) and an allogeneic group (number of mismatches higher than half of the antigens per HLA locus). Significant differences of CD163+ and CD163/CD14 ratio were found in the decidua parietalis when comparing the HLA-classII-allogeneic OD group with the non-OD IVF group (p = 0.047). This difference was not found for the HLA-class-II-syngeneic OD group. Limitations, reasons for caution Our study only focused on decidua basalis and parietalis, no other locations in the placentas. Larger sample size might be needed to verify the association between macrophages and HLA mismatches. Wider implications of the findings To our knowledge, this study is the first to quantify a higher CD163 positive M2 macrophages load within the total decidual macrophages of uncomplicated OD pregnancy compared to non-OD IVF pregnancies. Trial registration number not applicable

Decreased expression of ligands of placental immune checkpoint inhibitors in uncomplicated and preeclamptic oocyte donation pregnancies

Oocyte donation (OD) pregnancies are characterized by a complete immunogenetic dissimilarity between mother and fetus, which requires enhanced immunoregulation compared to naturally conceived (NC) pregnancies. The trophoblast expresses co-inhibitory ligands crucial for regulation of the maternal T cell response. Therefore, we studied the role of placental immune checkpoint inhibitors for the establishment of fetal tolerance and their relation to the development of preeclampsia in OD compared to NC pregnancies. Placental tissue from uncomplicated OD (n = 21) and NC (n = 21) pregnancies, and OD (n = 9) and NC (n = 15) pregnancies complicated with preeclampsia were studied. Protein expression of co-inhibitory ligands PD-L1 and CD200 was double blind semi-quantitatively determined by immunohistochemistry. Messenger RNA expression of PD-L1, CD200 and indoleamine 2,3-dioxygenase (IDO) was determined using qPCR. Decreased PD-L1 and CD200 protein expression and increased IDO mRNA expression was observed in uncomplicated OD versus NC pregnancies (all p < 0.05). CD200 protein expression was positively correlated with PD-L1 expression in all groups, with the number of HLA total mismatches and with HLA class I mismatches in uncomplicated OD cases (all p < 0.05). Preeclamptic cases showed lower PD-L1 protein and CD200 protein and mRNA expression in OD compared to NC pregnancies (all p < 0.05). This study shows that signaling by co-inhibitory PD-L1 and CD200 and by immunosuppressive IDO is altered in the placenta of OD pregnancies, suggesting a contribution to the higher risk for preeclampsia. These insights provide future prospects in unraveling the immune paradox of oocyte pregnancy, which are applicable for better risk management and treatment of uncomplicated and preeclamptic pregnancies.

102. Changes in the reactive species interactome in oocyte donation pregnancies and pre-eclampsia

Introduction Oocyte donation (OD) is an artificial reproductive technique after which the fetus is completely allogenic to the mother. OD pregnancies carry a higher-than-normal risk to develop pre-eclampsia, which is characterized by an angiogenic imbalance, endothelial dysfunction and oxidative stress. Objective/Hypothesis We sought to investigate oxidative stress status in OD and pre-eclampsia by the measurement of different elements of the reactive species interactome (RSI). We hypothesized that the RSI is affected by OD and pre-eclampsia. Methods Between 2012 and 2016, sera were collected from women with uncomplicated naturally conceived (NC) pregnancies (n = 23), uncomplicated OD pregnancies (n = 27), NC pregnancies complicated by pre-eclampsia (n = 24) and OD pregnancies complicated by preeclampsia (n = 5). Indicators for reactive species production such as free thiols, protein-bound nitric oxide (RxNO), nitrite, nitrate, 8-iso-prostaglandin F2a, sulfate, and thiosulfate were measured using a variety of analytical techniques in serum. Results Nitrite levels were higher in uncomplicated OD pregnancies compared to NC pregnancies (p 0.001) and free thiol levels seem lower in OD compared to NC pregnancies. OD pregnancies complicated by pre-eclampsia resulted in decreased nitrite levels (p = 0.001) and decreased free thiol levels (p 0.001) compared to uncomplicated OD pregnancies. Decreased nitrite (p = 0.01) and free thiol levels (p 0.001) were also seen in NC pregnancies complicated by pre-eclampsia compared to uncomplicated NC pregnancies. RxNO levels(p = 0.005) and sulfate levels (p = 0.001) were increased in NC pregnancies complicated by pre-eclampsia compared to uncomplicated NC pregnancies. Discussion OD pregnancies differ from NC pregnancies with respect to the RSI. Changes in the RSI in uncomplicated OD pregnancies suggest a role for perturbations in redox status in the development of pre-eclampsia in OD. Redox differences between pre-eclampsia after OD and pre-eclampsia after NC pregnancy suggest variations in what triggers their initiation and progression. The RSI might represent a therapeutic opportunities to prevent pre-eclampsia in OD pregnancies.

Loss of placental thrombomodulin in oocyte donation pregnancies

To investigate whether thrombomodulin dysregulation is involved in the development of preeclampsia after oocyte donation (OD). Women who become pregnant after OD are prone to develop preeclampsia, a syndrome characterized by an aberrant immunologic response, hypercoagulability, and endothelial dysfunction. A mediator of inflammation and coagulation is thrombomodulin, which has a possible role to play in this syndrome. Case-control study. Not applicable. Placentas from 82 women with an uncomplicated pregnancy (48 naturally conceived, 21 IVF, and 33 OD pregnancies) and 9 women with an OD pregnancy complicated by preeclampsia have been studied. None. Abundances of thrombomodulin protein and vitamin D receptor (VDR) were determined using immunohistochemistry; mRNA expression was determined using quantitative polymerase chain reaction. Placental thrombomodulin protein abundance was lower in OD pregnancies (diffuse pattern in 45%) than in controls (diffuse pattern in 96%). Placental thrombomodulin mRNA expression was lower in OD pregnancies complicated by preeclampsia (0.72 ± 0.47) compared with in uncomplicated OD pregnancies (0.43 ± 0.18). Thrombomodulin expression correlated with inflammation and coagulation. VDR expression was decreased in OD pregnancies complicated by preeclampsia and was correlated with thrombomodulin mRNA. Pregnancies conceived through OD lose placental thrombomodulin expression. This loss is associated with an increased coagulation and inflammation and indicates that endothelial protection is diminished in OD pregnancies, which might be an explanation for the increased risk for preeclampsia. Vitamin D metabolism is dysregulated in OD pregnancies and might be a target for therapy.

11 Fetomaternal and peripheral immune status in preeclamptic and normotensive oocyte donation cases

Oocyte donation (OD) is a high risk for preeclampsia because a fetus is a complete allograft to the maternal host. However the differences of immune status between preeclamptic OD cases and normotensive OD cases have not been clarified. Objective To clarify the immunological differences between preeclamptic OD cases and normotensive OD cases. Methods Deciduel CD3+Tcells, CD4+Tcells, CD8+Tcells, Foxp3+Treg cells CD56+NK cells and CD68+ macrophage were evaluated by immunohistochemistry. Peripheral blood effector Treg cells were evaluated by flow cytometry in 5 preeclamptic OD cases and 16 normotensive OD cases. Results The populations of CD3+ T cells, CD4+ T cells, CD8+ T cells, Foxp3+ Treg cells, CD56+ NK cells and CD68+ macrophage in placental bed biopsy samples of OD cases were significantly lower compare to those in normal pregnancy subjects. Those levels in preeclamptic OD cases were similar to those in normotensive OD cases. Same findings were observed in preeclamptic cases in natural conception. Vascular remodeling of spiral arteries was very poor in OD cases regardless of the presence of preeclampsia. These findings were quite similar to those in preeclampsia of natural conception. Peripheral blood-effector Treg cells was significantly decreased in preeclampsia, but these levels in OD pregnancies were not changed in preeclamptic OD cases and normotensive OD cases. Conclusion Poor vascular remodeling and some of the immunological changes were observed in uncomplicated OD pregnancy, but we have not yet identified the crucial factors that lead to preeclampsia in OD pregnancy.

A new era in reproductive medicine: consequences of third-party oocyte donation for maternal and fetal health.

The fetus is a semi-allograft for the maternal host in natural pregnancy, but the fetus is a complete allograft after oocyte donation (OD), and there is greater antigenic dissimilarity with the mother. Thus, OD pregnancy is a good model for understanding how the fetus is protected by the maternal immune system. Recent clinical data have revealed a higher risk of miscarriage, gestational hypertension, preterm birth, and low birth weight with OD pregnancy. There is also a higher incidence of chorionic deciduitis, dense fibrinoid deposits in the chorionic basal plate, inflammatory lesions in the chorionic plate, and C4d deposition on syncytiotrophoblasts in OD pregnancy. Impaired accumulation of T cells, regulatory T (Treg) cells, natural killer (NK) cells, and monocytes in the decidua basalis and poor remodeling of spiral arteries are observed in OD pregnancy irrespective of whether preeclampsia occurs. These findings may partly explain why OD pregnancy is associated with a high risk of gestational hypertension and preeclampsia. We need to clarify the immunological and pathological differences between uncomplicated and complicated OD pregnancy. In uncomplicated OD pregnancy, the level of HLA match between mother and baby is significantly higher than would be expected by chance, suggesting that miscarriage may be frequent with marked HLA mismatch. This review discusses the relationship between various aspects of the immune system and complications of OD pregnancy.

Innate immune proteins, SP-A, SP-D and MBL-A, are expressed by murine testicular germ cells and are positively regulated by testosterone

Oocyte donation (OD) enables women with various causes of reproductive failure to conceive, but is accompanied with a high risk for certain pregnancy disorders. Possibly, the allogeneic nature of the fetus in OD pregnancies plays a role in the development of these disorders. In this study, we investigated whether there is a selection for some degree of HLA matching in successful and uncomplicated OD pregnancies. Mothers and children from OD pregnancies that made use of unrelated donors (n=75) were typed for HLA-A,-B,-C,-DR,-DQ and the observed number of HLA matches of the child was compared with the expected number of HLA matches. Moreover, we studied the possibility of a preferential selection for maternal KIR and fetal C combinations. We observed a significantly higher level of HLA matching betweenmother and child than expected by chance. Especially the incidenceof childrenwith5ormoreHLAmatches,which is the situation in autologous pregnancy, was higher than expected. A higher level of matching was shown especially for HLA class I, while no significant differences were observed for the individual HLA loci. With respect to maternal KIR and fetal HLA-C no selection for a favorable combination was found. Larger observational studies including uncomplicated, preeclamptic and aborted pregnancies are essential to determine to what extent HLA matching affects the outcome of OD pregnancies.

Selective advantage of HLA matching in successful uncomplicated oocyte donation pregnancies

Oocyte donation (OD) enables women with various causes of reproductive failure to conceive, but is accompanied by a high risk of certain pregnancy disorders. Possibly, the allogeneic nature of the fetus in OD pregnancies plays a role in the development of these disorders. In this study, we investigated whether there is a selection for some degree of HLA matching in successful and uncomplicated OD pregnancies. Mothers and children from OD pregnancies that used unrelated donors (n=75) were typed for HLA-A, -B, -C, -DR, and -DQ and the observed number of HLA matches of the child was compared with the expected number of HLA matches. Moreover, we studied the possibility of a preferential selection for maternal KIR and fetal C combinations. We observed a significantly higher level of HLA matching between mother and child than expected by chance. In particular, the incidence of children with 5 or more HLA matches, which is the situation in autologous pregnancy, was higher than expected. A higher level of matching was shown, especially for HLA class I, while no significant differences were observed for the individual HLA loci. With respect to maternal KIR and fetal HLA-C no selection for a favorable combination was found. Larger observational studies including uncomplicated, preeclamptic, and aborted pregnancies are essential to determine to what extent HLA matching affects the outcome of OD pregnancies.

Differential immunoregulation in successful oocyte donation pregnancies compared with naturally conceived pregnancies

In oocyte donation (OD) pregnancies, there is a higher level of antigenic dissimilarity between mother and fetus compared with naturally conceived (NC) pregnancies. We hypothesize that a higher degree and/or a different type of immunoregulation is necessary to maintain an uncomplicated OD pregnancy. Different immunological aspects of successful OD pregnancies (n=28) were compared with those of NC pregnancies (n=51), and non-donor IVF (n=20) pregnancies. Maternal peripheral blood mononuclear cells (mPBMCs) were characterized by flow cytometry; the outcome correlated with the number of mother–child HLA mismatches. The fetus-specific alloreactivity of mPBMCs was measured in a mixed lymphocyte reaction. The percentages of CD4+CD25bright and CD4+CD25dim cells were higher in mPBMCs of OD and IVF pregnancies compared with NC pregnancies. The percentage of CD4+CD25dim cells in mPBMCs of OD pregnancies correlated positively with the number of HLA mismatches. Functional studies showed a lower proliferative response to umbilical cord blood by mPBMCs in OD pregnancies. In conclusion, we found a higher degree of peripheral immunoregulation in OD and IVF pregnancies compared with NC pregnancies. A higher number of HLA mismatches in successful OD pregnancies leads to increased percentages of activated T cells in peripheral blood, but not to a higher alloreactivity to the fetus. These studies show that immunoregulation in OD pregnancy is different from that in NC pregnancies. The antigenic dissimilarity in OD pregnancies may play a role in the pathophysiology of preeclampsia.