A blinded multicenter investigation: Accentuated NK lymphocyte CD335 (NKp46) expression predicts reproductive failures after IVF.

The peripheral blood NK cell diversity is highly complex. Recent studies have described more than a thousand phenotypes sharing NK cell receptors (NKRs), across the leukocyte lineages. Previously, we have found that accentuated NK p46 phenotype has prognostic value for NK cytotoxicity status, and is characteristic for patients with recurrent implantation failure (RIF).

Accentuated Peripheral Blood NK Cytotoxicity Forms an Unfavorable Background for Embryo Implantation and Gestation.

Problem Many studies have demonstrated the negative impact of high rates of NK cytotoxicity (NKc) on reproductive processes, but there is no agreement as to the appropriateness and feasibility of using the NKc for routine diagnostic in IVF patients. This study conducted a retrospective analysis of embryo transfer (ET) success rates and live birth rates (LBR) in patients with different NKc values. Method of study 1854 cycles of ET were selected and divided into three groups according to NKc levels, and randomized by anamnesis and age: normal (nNKc, n = 871), elevated (eNKc, n = 759), and reduced NKc (rNKc, n = 123).

Natural killer frequency determines natural killer cytotoxicity directly in accentuated zones and indirectly in "moderate-to-normal frequency" segment.

Natural killer (NK) frequency and NK cytotoxicity (NKc) are key determining factors of a clinical outcome. In our previous study, we showed the prognostic clinical significance of immune parameters when they are beyond the optimal range (accentuated). In this study, we attempted to explain the disparity of accentuated but physiologically and immunologically normal NK parameters that might serve as negative clinical prognostics indications of failed pregnancies.

Expression of natural cytotoxicity receptor NKp46 on peripheral blood natural killer cells in women with a history of recurrent implantation failures.

Aim: The peripheral blood natural killer (NK) cells diversity is highly complex; recent studies described more than a thousand phenotypes sharing NK cell receptors, across the leukocyte lineages. In this study, we investigated the expression of NKp46 in peripheral blood NK cells in women with a history of recurrent implantation failures (RIF) with euploid embryos with pre-implantation genetic diagnosis (PGD) and control group (donors of oocytes and surrogate mothers).

Methods: The expression of NKp46 in peripheral blood lymphocytes and NK cells from women with RIF (n = 57) and control group (n = 50) was analyzed with three-color flow cytometry.

Enumeration of peripheral blood NKp46 positive NK lymphocytes reflects NK cytotoxic activity in vitro.

Natural killer (NK) cells are the predominant innate lymphocyte subsets that mediate anti-tumor and anti-viral responses. The monitoring of NK cells function is important in various physiological and pathological conditions. Different approaches have been used to directly or indirectly evaluate NK cells activities.