post Ph.D research fellow, P.D. Hinduja Hospital and Medical Research Centre
In In-Vitro fertilization, many infertile cases are observed having the normal physiological parameters and even good quality embryos. This cases are called unexplained infertility. They often suffer from repeated implantation failure. In such cases, the endometrium i.e uterine lining may not be capable to hold the embryo, making the endometrium non-receptive. To evaluate the receptivity of endometrium to attach the embryo, we are doing research on genomic level. In this project we are studying the levels of genes in the endometrial tissue of such infertile patients and compare them with normal women with proven fertility. This suggests whether the particular genes are having higher or lower (improper) levels in infertile patients than fertile women. To tests this, we have used whole genome approach in which entire human genome is screened in a single reaction at a same time. After using this approach massive amount of data was generated, which was subjected to bio-informatics tools to generate data relevant to implantation failure and endometrial receptivity. This short-listed data was then validated using another method called Real Time PCR. Along with the gene expression, we have also studied their DNA for the methylation profile in such patients. In our body, methyl group gets added to particular region of DNA (this is called methylation). It is reported that methylation proves either helpful or harmful for human body. We are studying the status of methylation in such infertile patients that can have effect on receptive capacity of endometrium. Even for this, we have used whole genome approach. We have revealed the important immunological markers which are accountable for defective receptivity of endometrium, making them infertile. We are in the process of designing the panel of these genes to test the receptivity in infertile patients undergoing IVF to check their immunological status. This could give us the information about the capacity of endometrium to hold the embryo.
Abstract: There is ongoing interest in immune-suppressant corticosteroid drugs such as prednisolone to treat infertility in women with repeated IVF failure and recurrent miscarriage. The rationale draws on the pervasive but flawed view that immune activation is inconsistent with normal pregnancy. This ignores clear evidence that controlled inflammation and activation of the immune response is essential for embryo implantation. Generally, the immune response actively promotes reproductive success - by facilitating endometrial receptivity and tolerance of the foreign embryo, and promoting vascular adaptation to support placental morphogenesis. The peri-conception immune response also establishes developmental trajectories that can impact on fetal growth and gestational age at birth. Here, we describe immune changes accompanying conception that could be impeded by inappropriate corticosteroid administration. While women with specific clinical conditions may benefit from the anti-inflammatory and immune-deviating actions of prednisolone and related drugs, it is incorrect to assume a 'one-size-fits-all' approach. Better diagnostics and more preclinical studies are essential to define patient groups, build evidence for efficacy and fine-tune treatments so as not to inhibit essential actions of immune cells. We argue that unless overt immune pathology is evident, utilization of corticosteroids is not warranted and may be harmful. In most women, perturbing immune adaptation at implantation is expected to adversely influence placental development and impair immune-mediated quality control mechanisms, potentially elevating risk of altered fetal growth and developmental programming, congenital anomalies and preterm birth.
Pub.: 04 Sep '16, Pinned: 29 May '18
Abstract: The inner uterine lining (endometrium) is a unique tissue going through remarkable changes each menstrual cycle. Endometrium has its characteristic DNA methylation profile, although not much is known about the endometrial methylome changes throughout the menstrual cycle. The impact of methylome changes on gene expression and thereby on the function of the tissue, including establishing receptivity to implanting embryo, is also unclear. Therefore, this study used genome-wide technologies to characterize the methylome and the correlation between DNA methylation and gene expression in endometrial biopsies collected from 17 healthy fertile-aged women from pre-receptive and receptive phase within one menstrual cycle. Our study showed that the overall methylome remains relatively stable during this stage of the menstrual cycle, with small-scale changes affecting 5% of the studied CpG sites (22,272 out of studied 437,022 CpGs, FDR < 0.05). Of differentially methylated CpG sites with the largest absolute changes in methylation level, approximately 30% correlated with gene expression measured by RNA sequencing, with negative correlations being more common in 5' UTR and positive correlations in the gene 'Body' region. According to our results, extracellular matrix organization and immune response are the pathways most affected by methylation changes during the transition from pre-receptive to receptive phase.
Pub.: 22 Jun '17, Pinned: 29 May '18
Abstract: Implantation failure (IF) even after the good-quality embryo transfer (ET) is main obstacle in in vitro fertilization (IVF). We aim to study the genomics of endometrial receptivity in IF patients under controlled ovarian stimulation (COS) during which ET is generally practised in IVF.Endometrial gene expression profiling in IF patients (n=10) and oocyte donors (n=8) were compared during window of implantation under COS by microarray. Enrichment analysis of microarray data was performed to determine dysregulated pathways. Microarray results were validated by real-time PCR. Localization of genes related to immune response (progestagen-associated endometrial protein (PAEP), leukaemia inhibitory factor (LIF), interleukin-6 signal transducer (IL6ST) was detected by immunohistochemistry.The gene ontology, pathway analysis and enrichment mapping revealed significant downregulation in activation and regulation of immune and inflammation response in IF patients under COS. The lower expression of PAEP, LIF and IL6ST in cases compared to controls by real time and immunohistochemistry suggests the functional importance of these genes.Importance of immune and inflammatory response in endometrial receptivity adds on to the current knowledge of gene expression profile in IF under COS. The panel of genes involved in these pathways would be useful in determining further line of treatment for IF during IVF.
Pub.: 30 Mar '17, Pinned: 29 May '18