Granulocyte-Colony Stimulating Factor Related Pathways Tested on an Endometrial Ex-Vivo Model

Abstract

IntroductionRecombinant human Granulocyte-Colony Stimulating Factor (rhG-CSF) supplementation seems to be a promising innovative therapy in reproductive medicine, used in case of recurrent miscarriage, embryo implantation failure or thin endometrium, although its mechanisms of action remain unknown. Our aim was to identify possible endometrial pathways influenced by rhG-CSF.Materials and MethodsHypothetical molecular interactions regulated by G-CSF were designed through a previous large scale endometrial microarray study. The variation of endometrial expression of selected target genes was confirmed in control and infertile patients. G-CSF supplementation influence on these targets was tested on an endometrial ex-vivo culture. Middle luteal phase endometrial biopsies were cultured on collagen sponge with or without rhG-CSF supplementation during 3 consecutive days. Variations of endometrial mRNA expression for the selected targets were studied by RT-PCR.ResultsAt the highest dose of rhG-CSF stimulation, the mRNA expression of these selected target genes was significantly increased if compared with their expression without addition of rhG-CSF. The selected targets were G-CSF Receptor (G-CSFR), Integrin alpha-V/beta-3 (ITGB3) implicated in cell migration and embryo implantation, Plasminogen Activator Urokinase Receptor (PLAUR) described as interacting with integrins and implicated in cell migration, Thymidine Phosphorylase (TYMP) implicated in local angiogenesis, CD40 and its ligand CD40L involved in cell proliferation control.ConclusionRhG-CSF seems able to influence endometrial expressions crucial for implantation process involving endometrial vascular remodelling, local immune modulation and cellular adhesion pathways. These variations observed in an ex-vivo model should be tested in-vivo. The strict indications or counter indication of rhG-CSF supplementation in reproductive field are not yet established, while the safety of its administration in early pregnancy on early embryogenesis still needs to be demonstrated. Nevertheless, rhG-CSF appears as a promising therapy in some difficult and unsolved cases of reproductive failure. Indications of pre-conceptual rhG-CSF supplementation may derive from a diagnosed lack of endometrial expression of some target genes.

Granulocyte colony-stimulating factor in repeated IVF failure, a randomized trial

“…The authors concluded that this cytokine could have an important function in achieving or maintaining pregnancy (Salmassi et al 2005). In another study, Rahmati and coworkers demonstrated significantly lower levels of GCSF receptors at the maternal-fetal interface in infertile women with implantation failure, and interestingly, stimulation with high-dose GCSF was able to increase the expression of GCSF receptors in these patients (Rahmati et al 2014). GCSF might affect reproduction, implantation, and pregnancy through several possible mechanisms; GCSF has been shown to induce the trophoblast proliferation, invasion, and maintenance during pregnancy (Miyama et al 1998, McCracken et al 1999.…”

“…Many couples still remain unsuccessful after several IVF attempts causing deep effect on quality of life and a heavy financial burden (Zeyneloglu & Onalan 2014). With the recent advances in understanding the important role of granulocyte colony-stimulating factor (GCSF) in reproduction, and the detection of GCSF receptors in placental cytotrophoblasts, syncytiotrophoblasts, decidual stromal cells, endometrial gland cells, and follicular cells (Saito et al 1994, Miyama et al 1998, McCracken et al 1999, Salmassi et al 2005, Ledee et al 2008, Rahmati et al 2014, GCSF started to attract attentions in gynecology, especially in patients with recurrent abortions and/or infertility.…”

The role of G-CSF in recurrent implantation failure – a randomized double blind placebo control trial

“…In a randomized trial endometrial injury resulted to a significant improvement (nearly development) in the implantation and clinical pregnancy and live birth rate (27.7%, 66.7% and 48.9% respectively) compared with control subjects who did not have endometrial biopsies (28,29). G-CSF administration appears to be associated with an increase in regulatory T cells and dendritic cells and appears to influence endometrial expression of genes which have cardinal role in implantation process (30)(31)(32)(33).…”

Immunogenetic contributions to recurrent pregnancy loss

“…They also proliferate in response to granulocyte colony stimulating factor (G-CSF). Some have postulated that this action of G-CSF may reduce the incidence of miscarriage as they can recognize HLA-C on extravillous cytotrophoblasts [68][69][70]87].…”

“…This diagram gives a general overview. Estrogen, βHCG, and G-CSF are all known to induce expression of Treg cells and migration to the endometrium [68][69][70][71]. There they express IL-10, TGFβ, and TNFα [10].…”