Circulating Innate Lymphoid Cells Exhibit Distinctive Distribution During Normal Pregnancy

Over the past decades, the investigation of innate lymphoid cells (ILCs) has revealed their significance in successful pregnancy. Sex hormones, such as estradiol and progesterone, show specific changes during pregnancy and modulate both adaptive and innate immune systems. ILC subset distribution in peripheral blood of pregnant women and its potential association with sex hormone levels have not been well revealed. Peripheral blood was obtained from healthy non-pregnant, early-pregnant, and late-pregnant women. Radioimmunoassay was performed to measure plasma estradiol and progesterone levels. The levels of type 1 ILCs (ILC1s), type 2 ILCs (ILC2s), type 3 ILCs (ILC3s), and total ILCs as well as estrogen and progesterone receptors of ILC2s in peripheral blood were analyzed using flow cytometry. The proportion of total ILCs and distribution of ILC subsets in peripheral blood changed dynamically during pregnancy. Compared to non-pregnant women, late-pregnant women displayed significantly higher proportion of circulating ILCs, among which ILC2s accounted for the majority in late-pregnant women while a smaller part in others, and ILC3s displayed the opposite. Plasma estradiol and progesterone levels elevated while pregnancy proceeded and the expression of their receptors in ILC2s increased consisted with the proportion of circulating ILC2s. Our work first observed the existence of progesterone receptors in human circulating ILC2s and revealed the distribution pattern of circulating ILC subsets and their interrelation with plasma sex hormone levels during pregnancy. Our results suggested that the estradiol and progesterone levels might partly influence the distribution of circulating ILC subsets and implied the interplay between circulating ILCs and pregnancy.

239 Increased Preovulatory Estradiol Improves Pregnancy Success of Embryo Transfer in Beef Cows

Preovulatory estradiol concentrations and expression of estrus have been associated with greater pregnancy rates in beef cattle following AI, thus an experiment was designed to determine if supplemental estradiol (E2) at GnRH-induced ovulation would improve pregnancy retention in postpartum beef cows after embryo transfer. Cows were synchronized with the 7-d CO-Synch + CIDR® protocol. On d0 (48h post-prostaglandin) cows were grouped by estrual status (Estrual; n=198, nonestrual; n=406). Nonestrual cows were administered GnRH and randomly assigned to either no treatment (Control; n=204) or administration of 0.1 mg (IM) estradiol 17-β (Estradiol; n=202). In a preliminary study, 0.1 mg (IM) estradiol 17-β increased plasma estradiol (17.11±3.4 pg/mL; P < 0.01) and remained elevated above baseline for approximately 8h compared to control (1.70±0.58 pg/mL). All cows received an in vivo produced embryo on d7. Embryos were matched by grade, stage, and flush across treatments. Pregnancy was classified on d30 by either plasma pregnancy-associated glycoproteins analysis (Year 1) or ultrasonography (Year 2). Plasma estradiol concentrations (d-2, d0h0, d0h2) were analyzed by PROC MIXED as repeated measures in SAS(9.4), while GLIMMIX procedures were used to analyze differences in pregnancy rates with treatment, group, year, and their interactions as fixed effects. There was a treatment by time interaction (P < 0.001) in E2 concentration. There was no difference in plasma E2 concentrations on d0h0 (P >0.30) between treatments. At d0h2, Estradiol cows (15.7±0.25 pg/mL) had greater plasma E2 compared to Estrual (4.0±0.13 pg/mL) or Control (3.4±0.25 pg/mL) cows (P < 0.001), and Estrual cows had greater plasma E2 than Control cows (P = 0.02). Control cows had decreased (26%) pregnancy rates compared to both Estradiol (37%; P = 0.03) and Estrual (40%; P = 0.01) cows. Pregnancy rates did not differ (P = 0.51) between the Estrual and Estradiol cows. In conclusion, elevated preovulatory concentrations of estradiol are critical for improved pregnancy retention following embryo transfer.

Relationships Between Reproductive Hormones And Maternal Pregnancy Physiology In Women Conceiving With Or Without In Vitro Fertilization

We evaluated maternal pregnancy adaptations and their relationships with circulating hormones in women who conceived with or without in-vitro fertilization (IVF). Pregnancies were grouped by corpus luteal (CL) number: 1- CL with physiological plasma relaxin concentration (PRLN; spontaneous pregnancies); 0-CL without circulating RLN (programmed cycles); >1-CL with elevated PRLN (ovarian stimulation). Major findings: declines in plasma osmolality (Posm) and sodium concentration (PNa+) were comparable in the 1- and 0-CL cohorts, correlated with plasma estradiol and progesterone concentrations, but not PRLN; gestational declines in plasma uric acid concentration (PUA) were attenuated after IVF especially programmed cycles, partly due to subdued increases of renal UA clearance; PRLN and cardiac output (CO) were inversely correlated when plasma estradiol concentration was below ~2.5ng/ml, but positively correlated above ~2.5ng/ml. Unexpectedly, PRLN and plasma sFLT1 (PsFLT1) were directly correlated. Though PsFLT1 and CO were not significantly associated, CO was positively correlated with plasma PLGF concentration after the first trimester, particularly in women who conceived with 0-CL. Major conclusions: (1) circulating RLN was unnecessary for gestational falls in Posm and PNa+; (2) PRLN and CO were inversely correlated during early gestation suggesting PRLN in the lower range may have contributed to systemic vasodilation, while at higher PRLN, relaxin influence became self-limiting; (3) evidence for cooperativity between RLN and estradiol on gestational changes in CO was observed; (4) after the first trimester in women who conceived without a CL, plasma PLGF concentration was associated with recovery of CO, which was impaired during the first trimester in this cohort.

Estimates of correlation between estrus behavior and estradiol concentrations during estrus

Estrus traits have economic value in dairy production systems and can potentially be incorporated into genomic selection. Three studies were performed to further understand selection responses. Study one and two explored the relationship between rump touches and number of steps during estrus. Holstein-Friesian cows (n = 1197; Study 1) across five pasture-based grazing dairy herds were fitted with a capacitive touch sensing (CTS) device on the rump (FlashMate; Farmshed Labs Limited, Hamilton, NZ). The number of times touched and the sum of the touch duration were used to compare farms and estimate the intra-class correlation (repeatability). For Study 2, postpartum Holstein (n = 85) and Guernsey (n = 5) cows in a confinement-style dairy were used. Cows were fitted with an IceQube accelerometer (IceRobotics Ltd., Edinburgh, UK) to measure steps taken per hour and a CTS device was applied to both rumps. The inter-class correlation for the number of rump touches and number of steps taken during estrus was calculated. Study 1 had an intra-class correlation (repeatability) for rump touches during estrus was approximately 0.2. For Study 2, the number of steps and the number of rump touches during estrus increased in a synchronous manner. The inter-class correlation (r) for rump touches and steps was approximately 0.45. Experiment 3 focused on the association between circulating concentrations of estradiol and overt phenotypes for estrus [greater activity and (or) rump touches (mounts, chinrests, etc.)] that can be easily observed on farm. We also tested the effect of lactation on the estrus traits that we measured. Cows (n = 11 lactating and n = 9 nonlactating) were treated with PGF2[alpha] to synchronize estrus. The jugular vein was cannulated to collect blood every 2 h for plasma estradiol measurement. Plasma LH was measured during the periestrual period to determine the time of the LH surge. Cows were fitted with an IceQube accelerometer to measure activity (steps per h) and a CTS to measure the number of rump touches and total touch time. The correlation between plasma estradiol concentrations and overt signs of estrus ranges from near 0 for a cow coming into estrus to [greater than] 0.5 for a cow going out of estrus. Lactating cows had shorter estrus periods because the interval from the onset of estrus activity to the LH surge was shorter. Selection for a longer estrus period (based on activity) could potentially increase the interval from the onset of activity to the LH surge and provide for a longer estrus. In conclusion, the repeatability for rump touches during estrus was approximately 0.2 and this suggests that the maximum heritability for this estrus trait is 20 [percent]. Selection for the number of rump touches during estrus, therefore, should increase overt signs of estrus that include rump touches in dairy cows. The correlation between rump touches and the number of steps taken during estrus was 0.45. Selecting cows for increased activity should increase the number of rump touches (mounts, chin rests, etc.) because based on the correlation at least 20 [percent] (r[superscript 2]) of the variation in the number of steps was explained by the estrus cow walking in response to other cows interacting with her rump. Likewise, selecting cows for rump touches at estrus using a CTS device (or similar) should increase the number of steps during estrus. These data can be used to support large-scale phenotyping projects of cows with known genotypes to perform genome-wide association studies (GWAS) that can be used to identify genetic makers for estrus expression. These genetic markers for estrus expression can be incorporated into genetic selection indices to improve estrus expression in dairy cows.