Association between endometrial and peripheral blood immune profiles and reproductive outcome in patients with

recurrent pregnancy loss, repeated implantation failure and infertility MD Salazar

1, A Skariah

1, Y Hussein

1, H Elazzamy

2, S Dambaeva

2, K Beaman

2, A Gilman-Sachs

2, J Kwak-Kim

1,2

1Reproductive Medicine and Immunology, Department of Obstetrics and Gynecology,

2Department of Microbiology and Immunology, Chicago Medical School at Rosalind Franklin University of Medicine and Science, N. Chicago, USA

PROBLEM Implantation can only take place in a receptive uterus. In humans, the uterus becomes receptive during the mid-secretory phase

of the menstrual cycle, commonly known as the window of implantation. Several efforts have been made to find the best way to

evaluate the endometrial receptivity and improve the outcome of assisted reproductive technology. The endometrial immune

profile focuses on the IL-15 and Il-18 environment during the window of implantation. In the mid-luteal phase, stromal and endo-

thelial endometrial cells secrete IL-15, Fn-14, IL-18, and TWEAK at specific levels. Increased IL-15 allows the recruitment and

maturation of uNK cells. IL-18 and mature uNK cells stimulate Th2 cytokine production and lead to a predominantly Th2 balance.

This equilibrium promotes immunotrophism and angiogenesis, while inhibiting inflammatory and cytotoxic pathways. According to

a previous study the endometrial immune profile is established by a step-by-step procedure first considering the IL-18/TWEAK

mRNA ratio (reflecting local angiogenesis and possibly a Th1 deviation), then the CD56+ cell count (reflecting uNK cell mobiliza-

tion), and finally the IL-15/Fn-14 mRNA ratio (indicative of uNK cell maturation and uNK cytotoxic activation). This study reported

that the Endometrial immune profile was dysregulated in 81.7% of the RIF patients compared to controls; over activation was di-

agnosed in 56.6% and low activation in 25%. We previously reported that an abnormal increase in peripheral blood NK levels,

NK cytotoxicity and Th/Th2 cells ratio are associated with RPL, RIF and infertility. Therefore, we aimed to investigate if the endo-

metrial immune profile is associated with the peripheral blood immune profile and reproductive outcome in women with infertility,

RPL and RIF.

CONCLUSIONS

Figure 2. Endometrial immune profile among the groups

Figure 3. Association between endometrial immune profile and peripheral blood immune profile MATERIAL AND METHODS Design: Prospective cohort study

Study population: A total of 218 women (age 36.7±5.0) were enrolled in the Reproductive Medicine and Immunology at

RFUMS and Clinica las Condes, Santiago de Chile from November 2015 to August 2017. Women were divided into 4 groups

according to their reproductive history and included: controls (n=10, fertile women with at least one full term pregnancy), infertile

(n=61, failure to achieve a successful pregnancy after 12 months or more of appropriate, timed unprotected intercourse or ther-

apeutic donor insemination), RPL (n= 83, ≥ 2 spontaneous abortions) and RIF (n=64, ≥ 3 unsuccessful IVF/FET cycles). From

the 218 women that were enrolled, 32 women lost follow up, 78 women have pending conception cycles and 10 controls had no

conception cycles. Then, we followed up 98 women that went through a conception cycle ≤6 months after endometrial biopsy.

Patient treatment was individualized based on their peripheral blood immune profile, presence of thrombophilias, autoantibodies

status and hormonal needs and briefly consisted in the use of: luteal support with high dose of progesterone and estradiol, low

molecular weight heparin, low dose aspirin, vitamin E and anti-inflammatory medication or immune modulators (Prednisone,

IVIG, Tacrolimus, Plaquenil).

Laboratory: Endometrial biopsy was performed in mid-luteal cycle to determine their endometrial immune profile. The collected

endometrial tissue was investigated for routine pathology evaluation and endometrial dating, and molecular analysis. mRNA

was extracted from the endometrial tissue and converted into cDNA. IL-18, IL-15, fibroblast growth factor-inducible 14 (Fn14)

and TNF weak inducer of apoptosis (TWEAK) were analyzed by quantitative RT-PCR. In addition, peripheral blood immuno-

phenotype, NK cytotoxicity, and intracellular cytokine expression were analyzed by flow cytometry.

Statistical analysis: Differences between the groups were estimated using one-way ANOVA for continuous variables and Chi-

square for categorical variables. Statistical significance was set at P˂0.05.

RESULTS

Figure 4. Conception cycle outcome

Dysregulated endometrial immune profile is associated with infertility, RPL and RIF.

The endometrial gene expression is not correlated with the peripheral blood immune profile therefore we speculate the endome-

trial gene expression study may detect local dysregulated endometrial immune responses.

Lower peripheral blood NK cytotoxicity levels are associated with successful conception cycles.

The pregnancy rate after the personalized immune treatment of over active endometrial immune profile is similar to that of wom-

en with normal endometrial immune profile.

Further study is needed for the therapeutic modality of women with low endometrial immune profile.

No dysregulation

IL-18/TWEAK= 0.03-0.12

IL-15/Fn-14= 0.3-3

Over Immune activation

IL-18/TWEAK >0.12

±IL-15/Fn-14>3

Low Immune activation

IL-15/Fn-14 <0.3

±IL-18/TWEAK < 0.02

Figure 1. Endometrial Immune profile

Figure 9. Association between endometrial immune

profile and conception cycle outcome

Figure 5. Association between reproductive failure and

conception cycle outcome

Figure 6. Association between cycle type and

conception cycle outcome

Figure 7. Association between over-immune endometrial

activation and conception cycle outcome

Figure 8. Association between low-immune endometrial

activation and conception cycle outcome

Figure 10. Association between peripheral blood

immune profile and conception cycle outcome