Menstrual Cycle Dependent Fluctuations in NK and T‐Lymphocyte Subsets from Non‐Pregnant Human Endometrium

Abstract

Endometrial lymphocyte fluctuations during the menstrual cycle may reflect hormonal regulation of maternal immunity, thereby promoting tolerance at the time of implantation.

Normal percentage of CD56bright natural killer cells in young patients with a history of repeated unexplained implantation failure after in vitro fertilization cycles

“…We observed no difference in the percentage of endometrial CD56þ CD16-and of CD56bright CD16-cells, or in the percentage of CD3þ cells, or in the proportion of CD4þ and CD8þ, of the patients enrolled in the study when compared with the percentage of the same lymphocyte subpopulations reported in literature regarding normal human endometrium (13). Our results are comparable with the ones presented in literature, because the difference is not statistically significant either for CD3 (P¼.257) and for CD56þ/CD16À (P¼.616).…”

“…Flynn et al (13) demonstrated that in the LS phase, the proportion of NK cells CD56þ CD16-, expressed as a percentage of CD45þ, was about 83.2%, from 26.4% in the late proliferative (LP) phase, whereas the percentage of T lymphocytes in the LS phase was found to be 6.7% from 55% in the LP (15). The increase of the endometrial NK population and the decrease of the CD3þ lymphocyte proportion in the LS phase are likely to be of fundamental importance to the success of implantation.…”

“…To exclude any bias on lymphocyte populations' recovery deriving from the specific sample-processing protocol in two cases, we also tested in parallel (using fractions of the same sample) a different cell isolation procedure (13).…”

Roles of Mifepristone on the Regulation of Cytotoxic Lymphocytes and Regulatory T Cells

“…The results showed 536 that mifepristone could increase activated CLs rather than Tregs, which leads to the hypothesis that mifepristone serves as a drug for pregnancy termination due to the destruction of the endometrial immune microenvironment. A study found that T cells decrease from 55 to 6.7% between the late proliferative and the late secretory phages in the menopause cycle, and uNK cells rapidly increase up to 70% of uterine leukocytes in the late secretory phase and early pregnancy [13]. CLs can secret various cytokines and growth factors such as tumor necrosis factor-α, interleukin-10, GM-CSF, interleukin-1β, transforming growth factor-β1, CSF-1, LIF, and interferon-γ [14].…”

Trafficking of peripheral blood CD56bright cells to the decidualizing uterus—new tricks for old dogmas?

“…In-depth studies of direct endocrinological involvement in maternal immune regulation have often given apparently conflicting results. Effects of hormones, especially E 2 , on NK cell numbers, subsets and activity have been extensively reported in relation to the menstrual cycle (Hunt et al, 2000;Flynn et al, 2000;Bouman et al, 2001;Yovel et al, 2001;Sulke et al, 1985;Souza et al, 2001;Jones et al, 1997), pregnancy (Veenstra et al, 2002;Watanabe et al, 1997), reproductive pathologies (Provinciali et al, 1995;Somigliana et al, 1999;Searle et al, 1999), contraceptive use (Auerbach et al, 2002;Scanlan et al, 1995) and metatastic disease (Baral et al, 1995;Roszkowski et al, 1997) but there are no reports of an influence of sex hormones on NK cell trafficking in the human.…”