Human decidual gamma/delta T cells possess unique effector and TCR repertoire profiles during pregnancy

Human γδ T cells are enriched at the maternal-fetal interface (MFI, decidua basalis) showing a highly differentiated phenotype. However, their functional potential is not well-known and it is not clear whether this decidua-enrichment is associated with specific γδ T cell receptors (TCR) as is observed in mice. Here we addressed these open questions by investigating decidual γδ T cells during early and late gestation, in comparison with paired blood samples, with flow cytometry (cytotoxic mediators, cytokines) and TCR high-throughput sequencing. While decidual γδ T cells expressed less perforin than their counterparts in the blood, they expressed significant more granulysin during early pregnancy. Strikingly, this high granulysin expression was limited to early pregnancy, as it was reduced at term pregnancy. In contrast to this granulysin expression pattern, decidual γδ T cells produced reduced levels of IFNγ and TNFα (compared to paired blood) in early pregnancy that then increased by term pregnancy. TCR repertoire analysis indicated that human decidual γδ T cells are not generated early in life as in the mouse. Despite this, a specific enrichment of the Vγ2 chain in the decidua in early pregnancy was observed that disappeared later onwards, reflecting dynamic changes in the decidual γδ TCR repertoire during human gestation. In conclusion, our data indicate that decidual γδ T cells express a specific and dynamic pattern of cytotoxic mediators, Th1 cytokines and TCR repertoire suggesting an important role for these unconventional T cells in assuring a healthy pregnancy in human.

Early Pregnancy Human Decidua is Enriched with Activated, Fully Differentiated and Pro-Inflammatory Gamma/Delta T Cells with Diverse TCR Repertoires

Pregnancy is a state where high and stage-dependent plasticity of the maternal immune system is necessary in order to equilibrate between immunosuppression of harmful responses towards the fetus and ability to fight infections. TCR γδ cells have been implicated in the responses in infectious diseases, in the regulation of immune responses, and in tissue homeostasis and repair. The variety of functions makes γδ T cells a particularly interesting population during pregnancy. In this study, we investigated the proportion, phenotype and TCR γ and δ repertoires of γδ T cells at the maternal–fetal interface and in the blood of pregnant women using FACS, immunohistochemistry and spectratyping. We found an enrichment of activated and terminally differentiated pro-inflammatory γδ T-cell effectors with specific location in the human decidua during early pregnancy, while no significant changes in their counterparts in the blood of pregnant women were observed. Our spectratyping data revealed polyclonal CDR3 repertoires of the δ1, δ2 and δ3 chains and γ2, γ3, γ4 and γ5 chains and oligoclonal and highly restricted CDR3γ9 repertoire of γδ T cells in the decidua and blood of pregnant women. Early pregnancy induces recruitment of differentiated pro-inflammatory γδ T-cell effectors with diverse TCR repertoires at the maternal–fetal interface.

Survival role of superoxide dismutase 1 on human granulosa luteinized cells in vitro

OBJECTIVE

Deleterious effects of free radicals do not only result from the amount of free radicals produced but also are related to the efficiency and to the activities of enzymatic antioxidant systems. We investigated the effect of exogenous superoxide dismutase (SOD1) or Cu-chelating agent diethyldithiocarbamate (DDC) on the apoptosis (caspase-3 activity) of human granulosa luteinized cells (hGLC) in vitro.

METHODS

The effects of SOD1 and DDC were studied using in vitro culture system, caspase-3 and the total SOD activity in hGLCs were measured using AcDEVD-PNA substrate and Beaushap and Fridovich methods, respectively, after 48 h of the culture period.

RESULTS

The activity of SOD1 was the lowest in GLCs treated with 100 µM DDC as compared to control cells and to the cells supplemented with Cu, Zn-SOD or DDC (10 µM). The effect of DDC was associated with elevated caspase-3 activity as compared to control cells.

CONCLUSIONS

It was demonstrated for the first time that the supplementation of cultured hGLCs with Cu2+, Zn2+-SOD (200 U/ml) maintains the viability of hGLCs via caspase-3 suppression.

Antibodies against granulosa luteinized cells and their targets in women attending IVF program

PROBLEM

The study was conducted to investigate the presence and the possible role of anti-granulosa luteinized cells (GLCs) antibodies in infertile patients, attending in vitro fertilization (IVF) cycles, as well as to attempt the identification of putative target antigens.

METHOD OF STUDY

A total of 101 sera from infertile women (patient group) and 33 sera from fertile women (control group) were investigated. The patients were divided in subgroups according to: ovarian response to controlled ovarian hyperstimulation (COHS)--poor responders and good responders; fertilization rate--low fertilization rate and high fertilization rate. The relation between embryo transfer (ET) outcome and prevalence of anti-GLC antibodies was investigated too. NONIDET P-40 (NP-40) and whole-GLC lysates, as antigenic materials, were used in enzyme-linked immunosorbent assay (ELISA) and immunoblotting, respectively.

RESULTS

Based on the cut-off value of 2 S.D. above the control mean value, the prevalence of patients positive for anti-GLC antibodies was found to be 28.7% (29/101) compared with 9.1% (3/33) in control fertile women (P < 0.05). Anti-GLC antibodies were detected in 54.8% (17/31) of women with low fertilization rate compared with 15.7% (11/70) of women with high fertilization rate (P = 0.003) and it was established that women positive for anti-GLC antibodies had lower fertilization rate, than those negative for anti-GLC antibodies. Immunoblotting has demonstrated a number of GLC proteins with molecular masses (MM) of 110, 70-80, 47 and 37 kDa, frequently reacting with anti-GLC antibodies in patient's sera, as possible targets.

CONCLUSION

The presented results on the prevalence and role of anti-GLC antibodies, as well as the data on the target antigens confirmed our hypothesis about the potential involvement of GLC antigens in some cases of immunological infertility in IVF patients.