1. Background: In women, unexplained infertility has been associated with a range of cellular and molecular defects in the endometrium, adverse immune responses and immunological factors. Natural killer (NK) cells are included as they constitute the most abundant leukocyte population in the decidua. While decidua NK cells were extensively investigated, the study of endometrial eNK cells still lacks comprehensive researches. The reduction in eNK frequency has been associated with infertility status, in particular in the presence of a concomitant herpesvirus viremia. Since herpesviruses use as immune-escape HLA-G and HLA-E molecules, that are immune-inhibitory and important for a correct placentation, they could represent infertility co-factors. 2. Aims: Since lack of an accurate diagnosis in reproductive medicine leads to treatment failure, this proposal focuses on eNK cell characterization as a diagnostic factor for unexplained women infertility. We will evaluate also co-factors, taking into consideration herpesvirus infection and HLA-G and HLA-E expression. 3. Methods: Peripheral blood and endometrial NK cells will be immune-phenotyped and cell count and activation status (CD107a, IL-6, IL-10, IL-17) will be correlated with infertility condition. The implication of herpesvirus will be evaluated by DNA from peripheral blood and endometrial flushing samples analysis by HSV-1, HSV-2, EBV, CMV, HHV-6, HHV-7, VZV and HHV-8 specific primers an PCR technique. HLA-G and HLA-E expression will be analyzed in peripheral blood and endometrial environment by flow cytometry and ELISA tests and correlated by NK cell expression of their receptors (KIRs, LILRB1/2, NKG2A). 4. Expected results: On the basis of our preliminary results, we expect to identify NK cells as prognostic marker for primary unexplained infertility, with herpesvirus infection and HLA-G and HLA-E expression as co-factors. These data will be of importance in the management of infertile women.

NCT03581617

Conditions

1. Infertility, Female

Interventions

1. Diagnostic Test: NK cell analysis
2. Diagnostic Test: Herpesvirus detection
3. Diagnostic Test: sHLA-G analysis
4. Diagnostic Test: HLA-G 14bp INS/DEL typing
5. Diagnostic Test: sHLA-E analysis

MeSH:Infertility Infertility, Female

HPO:Female infertility Infertility

HLA-G expression is controlled by a polymorphism of insertion/deletion (ins/del) of 14 base pairs (rs66554220), where the deletion of 14bp stabilizes the mRNA producing higher levels of HLA-G (15).

We will genotype the women for rs66554220 polymorphism, to evaluate the implication in HLA-G levels of expression in infertile condition.