Numbers of natural killers lymphocytes do not determine their cytotoxicity

Natural killer’s cytotoxicity test accepted as a “gold standard“ for measuring natural killer’s function. However it is methodologically difficult for introduction in routine diagnos­tic practice. In our previous study, we showed a prognostic clinical significance of immune parameters when they are out of a optimal range (accentuated). In contrast, balan­ced “not accentuated” immune parameters associated with favorable clinical outcome. In this study, we attempted to explain the disparity of the accentuated but immunologically normal natural killer’s parameters that might serve as negative clinical prognostical biomar­kers indicative of failed pregnancies. We have analyzed number natural killers %, their cytotoxicity, and their reciprocal correlation in 8,664 patients with reproductive failures. We found an elevated natural killer’s cytotoxicity in a significant part of infertility population. An elevated natural killer’s cytotoxicity was significantly more often registered in patient with multiple reproductive failures (41.6 %) detected in patients with uncomplicated infertility (18.7 %). In the entire clinical population, % of natural killers correlates with their cytotoxicity. Interestingly, we found this correlation was strongly dependent on status of natural killer’s levels. Natural killer’s % – natural killer’s cytotoxicity correlation was strongest (r = 0.2021, p 17.5 %). Patients with amount of natural killers % between 15–17.5 % manifested lo­wer but significant correlation of natural killer’s % – natural killer’s cytotoxicity (r = 0.1213, p = 0.0155). Additionally, a significant correlation (r = 0.2689, p < < 0.0001) between natural killer’s % and natural killer’s cytotoxicity was observed in patients group with natural killer’s levels of < 7 % (1.7–7.3 %). While, patient groups with natural killer’s % (7.3–15 %) did not demonstrate correlation of natural killer’s % – natural killer’s cytotoxicity. Consistent with our hypothesis, the “balanced zone” of natural killer’s % is tightly controlled and, thus, does not correlate directly with cytotoxicity. In contrast, the “accentuated zones” of natural killer’s % escape this control and directly affected cytotoxicity

Beyond Uterine Natural Killer Cell Numbers in Unexplained Recurrent Pregnancy Loss: Combined Analysis of CD45, CD56, CD16, CD57, and CD138

Changes in the number and cytotoxic potential of uterine Natural Killer (uNK) cells have been associated with reduced fertility. To provide a better characterization of immunophenotypes in the endometrium of women with uRPL (unexplained recurrent pregnancy loss), we examined the applicability of a set of five immune cell markers. The concentration (cells/mm2) of CD45+ leukocytes, CD56+ uNK cells, and CD138+ plasma cells as well as of CD16+ and CD57+ cells, which indicate high cytotoxic uNK cells, were assessed by immunohistochemistry in endometrial biopsies from 61 uRPL patients and 10 controls. Control fertile endometria presented 90&ndash;300 CD56+ uNK cells/mm2. uRPL cases were classified in subgroups of low (uRPL-CD56low &lt; 90 cells/mm2), normal (uRPL-CD56normal 90&ndash;300 cells/mm2), and high uNK cell counts (uRPL-CD56high &gt; 300 cells/mm2). Some cases from the uRPL-CD56low and uRPL-CD56normal subgroups showed elevated proportions of cytotoxic CD16+ and CD57+ cells in relation to CD56+ cells. In the uRPL-CD56high subgroup, the CD57/CD56 ratio was reduced in most samples and the CD16/CD56 ratio was unaltered. Analysis of CD138 excluded the influence of chronic endometritis on these observations. Our results reinforce a link between uRPL and a dysfunctional endometrial environment associated with distinct immune cell profiles

Intrauterine insemination of cultured peripheral blood mononuclear cells prior to embryo transfer improves clinical outcome for patients with repeated implantation failures

International audienceImplantation failure is a major limiting factor in assisted reproduction improvement. Dysfunction of embryo-maternal immuno-tolerance pathways may be responsible for repeated implantation failures. This fact is supported by immunotropic theory stipulating that maternal immune cells, essentially uterine CD56(+) natural killer cells, are determinants of implantation success. In order to test this hypothesis, we applied endometrium immuno-modulation prior to fresh embryo transfer for patients with repeated implantation failures. Peripheral blood mononuclear cells were isolated from repeated implantation failure patients undergoing assisted reproductive technology cycles. On the day of ovulation induction, cells were isolated and then cultured for 3 days and transferred into the endometrium cavity prior to fresh embryo transfer. This immunotherapy was performed on 27 patients with repeated implantation failures and compared with another 27 patients who served as controls. Implantation and clinical pregnancy were increased significantly in the peripheral blood mononuclear cell test versus control (21.54, 44.44 vs. 8.62, 14.81%). This finding suggests a clear role for endometrium immuno-modulation and the inflammation process in implantation success. Our study showed the feasibility of intrauterine administration of autologous peripheral blood mononuclear cells as an effective therapy to improve clinical outcomes for patients with repeated implantation failures and who are undergoing in vitro fertilization cycles

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). ET with donors&rsquo; embryos (n = 101) were analyzed separately. NKc-to-K562 was measured in PBMC (peripheral blood mononuclear cells) by flow cytometry before ET. The patients did not obtain any additional treatments. Results Patients with eNKc, in addition to having reduced clinical pregnancy rates (OR1.59, p &lt; 0.0001), had increased levels of subsequent pregnancy failures (OR2.545, p &lt; 0.0001) when compared to nNKc patients. As a result, patients with eNKc had almost half the LBR than patients with nNKc (OR2.2, p &lt; 0.0001). In patients with rNKc, LBR was also lowered. eNKc was equally unfavorable for implantation and delivery in cryo- or fresh cycles. Markedly, eNKc was much more unfavorable for reproduction than slightly elevated NKc. The donor&rsquo;s embryos were implanted irrespective of the recipient&rsquo;s NKc levels, but the later stages of pregnancy were worse in patients with eNKc. Conclusions Our findings highlighted the negative impact of high levels of NK cytotoxicity on pregnancy outcomes