Clémence BELLEANNÉE's Lab.
Research on infertility.
In Canada, infertility affects more than 10% of couples wishing to have kids. Above 60% of these cases are caused by male factors or by a combination of male and female factors. Despite routine tests performed in fertility clinics, about 30% of infertility cases remain unexplained and, thus, cannot be treated. Acknowledging this growing health concern, our research aims at deciphering the basic mechanisms controlling the physiology of the reproductive systems in order to better diagnose and treat infertility problems.
Primary cilia are sensory organelles associated with
epididymal basal cells in adult mice
Unravelling the role of primary cilia in the control of male fertility
Recently, primary cilia have been found associated with epithelial cells of the epididymis, the organ in charge of spem maturation. These organelles are unique antennae that emerge on the surface of cells and are mediators of many signaling pathways involved in differentiation, proliferation and cell migration. In Human, primary cilia dysfunctions are associated with a broad spectrum of defects, including male infertility, that are commonly referred to as ciliopathies. Since primary cilia are essential to maintain the physiological functions of most organs, our research project aims at unravelling the role of primary cilia in epididymis development and homeostasis. This innovative project combines complementary in vitro and in vivo approaches on cell lines and mouse models. Considering the importance of epididymal functions in the control of sperm fertilizing abilities, carrying out this research will help decipher the cellular functions that may be impaired in some cases of male infertility.
The primary cilium is a sensory organelle controlling tissue development and homeostasis
Deciphering extracellular microRNA communication system
Ribonucleic acids (RNAs) are present in all cells as intermediates between genes and proteins as well as small non-coding RNAs. Among the later, microRNAs (miRNAs), control target genes expression and regulate many functions such as cell proliferation, differentiation and cell death. Importantly, miRNAs are involved in intercellular communication after being transferred from one cell to another by extracellular vesicles (EVs). However, despite their important role in intercellular communication, this mechanism remains poorly understood. Our research project aims at unravelling the complexity of extracellular miRNA (ex-miRNA) signaling in the epididymis, the organ of the male reproductive system responsible for sperm maturation. Our ultimate goal is to identify key molecular players governing reproductive biology and male fertility.
Role of extracellular vesicle and their miRNA cargo in intercellular communication
Impact of the sperm epigenome on the progeny outcome born by assisted reproductive technology
Since the first baby born by assisted conception in 1978, breakthroughs in assisted reproductive technologies (ARTs) allow 98% of infertile couples to have access to potentially successful treatments. However, despite great advances in the knowledge and optimization of ART efficiency, questions still need to be addressed regarding the potential adverse effects of these treatments, specially Intracytoplasmic Sperm Injection (ICSI). Our objective is to define the influence of the sperm epigenetic status on embryo development after ICSI and to determine the long-term consequences of using “epigenetically immature” spermatozoa for ARTs on child health. Our long-term goal is to develop strategies in collaboration with fertility clinics to favor the selection of "epigenetically mature" spermatozoa for IVF in order to reduce adverse effects on progeny outcome.
Funding: SickKids Foundation/CIHR
Intracytoplasmic Sperm Injection (ICSI)
Fluidic and hypoxia-controlled imaging system
Many physiological processes including post-testicular sperm maturation occurring in the male reproductive system, take place under sustained flow conditions. In addition to in vivo studies performed on transgenic mouse models, our laboratory uses different epididymal cell lines in vitro to decipher the mechanisms of intercellular communication that support the acquisition of sperm fertilizing abilities. It is now well established that physiological flow has profound impacts on cell functions within the organs of the male reproductive system. The BioFlux Imaging System provides the possibility of introducing a sustained flow to monitor cell responses with different controlled extracellular environments. This approach effectively emulates in vivo conditions applicable to different fields of research.
Funding: Canadian Funds for Innovation
BioFlux Imaging Technology