title: Cytokines and Blastocyst Hatching.
abstract: Blastocyst implantation into the uterine endometrium establishes early pregnancy. This event is regulated by blastocyst- and/or endometrium-derived molecular factors which include hormones, growth factors, cell adhesion molecules, cytokines and proteases. Their coordinated expression and function are critical for a viable pregnancy. A rate-limiting event that immediately precedes implantation is the hatching of blastocyst. Ironically, blastocyst hatching is tacitly linked to peri-implantation events, although it is a distinct developmental phenomenon. The exact molecular network regulating hatching is still unclear. A number of implantation-associated molecular factors are expressed in the pre-implanting blastocyst. Among others, cytokines, expressed by peri-implantation blastocysts, are thought to be important for hatching, making blastocysts implantation competent. Pro-inflammatory (IL-6, LIF, GM-CSF) and anti-inflammatory (IL-11, CSF-1) cytokines improve hatching rates; they modulate proteases (MMPs, tPAs, cathepsins and ISP1). However, functional involvement of cytokines and their specific mediation of hatching-associated proteases are unclear. There is a need to understand mechanistic roles of cytokines and proteases in blastocyst hatching. This review will assess the available knowledge on blastocyst-derived pro-inflammatory and anti-inflammatory cytokines and their role in potentially regulating blastocyst hatching. They have implications in our understanding of early embryonic loss and infertility in mammals, including humans.
authors.affiliation: Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, Karnataka, India.
authors.forename: Polani B
authors.initials: PB
authors.lastname: Seshagiri
authors.affiliation: Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, Karnataka, India.
authors.forename: Venkatappa
authors.initials: V
authors.lastname: Vani
authors.affiliation: Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, Karnataka, India.
authors.forename: Pathak
authors.initials: P
authors.lastname: Madhulika
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000276:immunology*; D016207:Cytokines / Q000276:immunology*; D010064:Embryo Implantation / Q000276:immunology*; D004717:Endometrium / Q000166:cytology / Q000276:immunology*; D005260:Female; D006801:Humans; D011247:Pregnancy / Q000276:immunology*; D014327:Trophoblasts / Q000166:cytology / Q000276:immunology*
chemical_list: D016207:Cytokines
keywords: Anti-inflammatory; female infertility; hatching failure; pro-inflammatory; proteases; zona lysis