ORIGINAL ARTICLE: Cell-Surface CD200 May Predict Efficacy of Paternal Mononuclear Leukocyte Immunotherapy in Treatment of Human Recurrent Pregnancy Loss

Screening and identification of key biomarkers associated with endometriosis using bioinformatics and next-generation sequencing data analysis

Background

Endometriosis is a common cause of endometrial-type mucosa outside the uterine cavity with symptoms such as painful periods, chronic pelvic pain, pain with intercourse and infertility. However, the early diagnosis of endometriosis is still restricted. The purpose of this investigation is to identify and validate the key biomarkers of endometriosis.

Methods

Next-generation sequencing dataset GSE243039 was obtained from the Gene Expression Omnibus database, and differentially expressed genes (DEGs) between endometriosis and normal control samples were identified. After screening of DEGs, gene ontology (GO) and REACTOME pathway enrichment analyses were performed. Furthermore, a protein–protein interaction (PPI) network was constructed and modules were analyzed using the Human Integrated Protein–Protein Interaction rEference database and Cytoscape software, and hub genes were identified. Subsequently, a network between miRNAs and hub genes, and network between TFs and hub genes were constructed using the miRNet and NetworkAnalyst tool, and possible key miRNAs and TFs were predicted. Finally, receiver operating characteristic curve analysis was used to validate the hub genes.

Results

A total of 958 DEGs, including 479 upregulated genes and 479 downregulated genes, were screened between endometriosis and normal control samples. GO and REACTOME pathway enrichment analyses of the 958 DEGs showed that they were mainly involved in multicellular organismal process, developmental process, signaling by GPCR and muscle contraction. Further analysis of the PPI network and modules identified 10 hub genes, including vcam1, snca, prkcb, adrb2, foxq1, mdfi, actbl2, prkd1, dapk1 and actc1. Possible target miRNAs, including hsa-mir-3143 and hsa-mir-2110, and target TFs, including tcf3 (transcription factor 3) and clock (clock circadian regulator), were predicted by constructing a miRNA-hub gene regulatory network and TF-hub gene regulatory network.

Conclusions

This investigation used bioinformatics techniques to explore the potential and novel biomarkers. These biomarkers might provide new ideas and methods for the early diagnosis, treatment and monitoring of endometriosis.

Role of lymphocyte immunization therapy (LIT) in repeated miscarriages - A review

Recurrent Miscarriages are seen in 2%-5% of women and 50% of these are labelled as unexplained as no underlying cause is found in them. Various studies have explained possible alloimmune basis in these couples. Lymphocyte Immunization Therapy (LIT) was the earliest immunomodulatory method suggested in these cases. The efficacy of LIT was questioned by REMIS study in 1999 and subsequent Cochrane reviews. However, recent meta-analyses have shown that LIT is not only effective in the treatment of repeated miscarriages but it is also safe. Review of the odds ratio for live birth of various meta-analyses of studies in recurrent miscarriages has also shown that newer meta-analyses have shown higher odds ratios. The purpose of this paper is to put forward the current perspective of LIT in reproductive failure and bring forth the recent evidence. In addition, we share our experience with the use of LIT in women with recurrent pregnancy losses. However, large multicentric RCTs are required to further prove efficacy of LIT.

Efficacy of Lymphocyte Immunotherapy in the Treatment of Recurrent Pregnancy Loss from Alloimmunity: A Systematic Review and Meta-Analysis

PROBLEM

The efficacy of lymphocyte immunotherapy (LIT) in the treatment of recurrent pregnancy loss (RPL) from alloimmunity has been debated for years. There is conflicting evidence on the therapeutic role of LIT, since the etiology of most cases of RPL are previously classified as idiopathic.

METHOD OF STUDY

A systematic search of PubMed and Cochrane databases was done for randomized controlled trials that assessed the efficacy of paternal lymphocyte or third donor LIT among patients with primary or secondary RPL. The primary outcome was live birth rate after LIT. Random-effect meta-analysis was conducted using the software RevMan 5.4. Pre-planned subgroup analyses of source of lymphocytes, timing and frequency of administration, and concentration per immunization dose were conducted.

RESULTS

Data from eight trials showed a statistically significant benefit of LIT (RR = 1.45, 95% CI 1.05 to 2.01). The overall live birth rate is higher in the treatment group (65.6%) compared to placebo or no treatment (45.2%). Subgroup analysis based on source of lymphocytes revealed a trend towards benefit with paternal LIT but with wide confidence interval (RR = 1.34, 95% CI = 0.84-2.14). Multiple doses of immunotherapy before pregnancy and low dose (5×10⁶ cells) LIT showed significant benefit. Sensitivity analysis involving studies with low risk of bias demonstrated significant benefit of increased live birth rate among patients treated with LIT compared to those who received placebo or no treatment (RR = 1.97, 95% CI = 1.53-2.53).

CONCLUSION

LIT demonstrate benefit in improving pregnancy outcome of patients with RPL from alloimmunity. This article is protected by copyright. All rights reserved.

Adverse drug reactions following lymphocyte immunotherapy for the treatment of infertility: A retrospective study

AIM

Unexplained infertility is a major burden for couples who want to have children. Lymphocyte immunotherapy (LIT) could be a therapeutic help for these couples. Although LIT has been carried out for decades, the data on the success of therapy are still controversial and there is hardly information on possible adverse drug reactions.

METHODS

In this study, we used a questionnaire to determine the frequency of local and systemic adverse drug reactions in our patients who were treated with LIT between 2017 and 2020 (n = 302). In addition, we asked about pregnancies and/or live births after LIT in a 2-year follow-up (n = 140).

RESULTS

Most of the patients reported the occurrence of mild local adverse drug reactions in a period of less than 4 weeks: Over 75% reported moderate erythema, itching or swelling, over 10% erythema, itching or swelling as more pronounced adverse drug reaction. Blistering was specified in 10% of the cases. Serious adverse drug reactions or adverse events were not described. In the follow-up, 69% of our patients stated a pregnancy after LIT, and 50% a life birth.

CONCLUSIONS

Overall, LIT represents a well-tolerated therapy for couples with unexplained infertility, however, more evidence is needed on the benefits.

Allogeneic lymphocytes immunotherapy in female infertility: Lessons learned and the road ahead

The endometrium is an essential tissue in the normal immunologic dialogue between the mother and the conceptus, which is necessary for the proper establishment and maintenance of a successful pregnancy. It's become evident that the maternal immune system plays a key role in the normal pregnancy's initiation, maintenance, and termination. In this perspective, the immune system contributes to regulating all stages of pregnancy, thus immunological dysregulation is thought to be one of the major etiologies of implantation failures. Many researchers believe that immune therapies are useful tactics for improving the live births rate in certain situations. Lymphocyte immunotherapy (LIT) is an active form of immunotherapy that, when used on the relevant subgroups of patients, has been shown in multiple trials to dramatically enhance maternal immunological balance and pregnancy outcome. The primary goal of LIT is to regulate the immune system in order to create a favorable tolerogenic immune milieu and tolerance for embryo implantation. However, there are a plethora of influential factors influencing its therapeutic benefits that merit to be addressed. The objective of our study is to discuss the mechanisms and challenges of allogeneic LIT.

Live Birth Rates after Active Immunization with Partner Lymphocytes

Although many potential causes have been established for recurrent implantation failure (RIF) and recurrent miscarriage (RM), about 50% of these remain idiopathic. Scientific research is focused on immunological risk factors. In the present study, we aim to evaluate live birth rates after immunization with paternal lymphocytes (lymphocyte immunotherapy (LIT)). This retrospective study consisted of 148 couples with a history of RM and/or RIF. The women underwent immunization with lymphocytes of their respective partners from November 2017 to August 2019. Fifty-five patients (43%) had live births. Stratified by indication (RM, RIF, combined), live birth rates in the RM and the combined group were significantly higher than that in the RIF group (53%, 59% and 33%, respectively, p = 0.02). The difference was especially noticeable during the first 90 days after immunization (conception rate leading to live births: 31%, 23% and 8% for RM, the combined group and RIF, respectively; p = 0.005), while there was no difference between groups during the later follow-up. LIT was associated with high live birth rates, especially in women with recurrent miscarriage. In view of the limited data from randomized studies, LIT cannot be recommended as routine therapy. However, it may be considered in individual cases.

Evaluation of paternal lymphocyte immunotherapy and potential biomarker mixed lymphocyte reaction-blocking factor in an Argentinian cohort of women with unexplained recurrent spontaneous abortion and unexplained infertility

PROBLEM

Analyze the effect of paternal immunotherapy treatment (PIT) in primary and secondary unexplained recurrent spontaneous abortion (URSA) and unexplained infertility (UI).

METHODS OF STUDY

A retrospective study analyzed a two-year follow-up between the generation of MLR-Bfs after PIT treatment (or controls first consultation) and a live birth. Recruited patients included primary URSA with two or more miscarriages at <12 weeks gestation, secondary URSA with previous live birth before two or more miscarriages, and UI with inability to conceive after 2 years of regular unprotected intercourse or in vitro fertilizations (IVF). PIT treated were compared with untreated controls.

RESULTS

Primary URSA: live birth was 241/416 (58%) versus 64/282 (23%) controls (p < .0001). Up to age 35, success was 158/217 (73%) and 37/144 (26%) controls (p < .0001). With 3 or more previous URSA, success was 90/135 (67%) versus 17/79 (22%) controls (p < .0001). Between ages 36 and 40, success was 69/147(47%) versus 22/98 (22%) controls (p < .0003), with 3 or more previous URSA live birth was 45/95 (47%) versus 6/46 (13%) controls (p < .0001). In UI, live birth was 99/298 (33%) versus 54/263 (21%) in controls (p < .0009) that increased under age 35 to 53/116 (46%) in treated versus 26/101 (26%) controls (p < .0056). In PIT treated, IVF success required a median of 1 (1.37 ± 0.67) versus a median of 3 IVF procedures (2.75 ± 0.84) in controls.

CONCLUSION

PIT is a successful treatment for primary and secondary URSA, and UI. PIT reduced the number of IVF required for achieving pregnancy.

Lymphocyte immunotherapy in recurrent miscarriage and recurrent implantation failure

PROBLEM

Lymphocyte immunotherapy (LIT) emerged in the early 1980s as a new therapeutic proposal for couples with a history of recurrent miscarriages (RM). However, in the early 2000s, the effectiveness of LIT was questioned. Recently, meta-analyses have observed the effectiveness and safety of LIT in treating couples with RM. Some studies evaluated the use of LIT in recurrent implantation failure (RIF) in in vitro fertilization cycles.

METHODS

This systematic and narrative review evaluated the data available in the literature regarding the efficacy and safety of the use of LIT. Searches in PubMed/Medline, Embase, and Cochrane Library databases were conducted, using the following keywords: "recurrent miscarriage," "lymphocyte immunotherapy," and "recurrent implantation failure".

RESULTS

This review describes the historical aspects of LIT and discusses its protocols, mechanisms of action, side effects, complications, and current evidence of the effectiveness in cases of reproductive failure. It also discusses the use of LIT during the COVID-19 pandemic and new immunological therapies.

CONCLUSION

In the vast majority of studies, the use of LIT for RM couples has shown an improvement in pregnancy outcomes. The most of the current studies that support the evidence are quasi-experimental, with few randomized, double-blind studies (Level of evidence III). However, the current evidence are not convincing for the use of LIT in RIF patients.

Association of CD200 expression in paternal lymphocytes with female Th1/Th2 balance and pregnancy establishment at immunotherapy of recurrent spontaneous abortion

PROBLEM

We hypothesized that expression of transmembrane glycoprotein CD200 on paternal lymphocytes used for pre-gestational lymphocyte immunotherapy (LIT) of recurrent spontaneous abortion (RSA) can suppress the pro-inflammatory Th1-type immunity required for successful implantation. To reveal the association between CD200 expression, female immune background after LIT, and pregnancy establishment, we have performed this work.

METHOD OF STUDY

Pre-gestational alloimmunizations were given to 37 women using paternal peripheral blood leukocytes, combined with additional alloimmunizations in case of pregnancy. Lymphocyte phenotypes were determined by flow cytometry. Cytokines produced by mitogen-stimulated female peripheral blood cells were estimated by FlowCytomix™ technology.

RESULTS

We have shown that 78.4% (29/37) of women became pregnant within 12 menstrual cycles after pre-gestational LIT. Pregnancy establishment depends on the intensity of CD200 expression, which is significantly higher on the CD200⁺ lymphocytes administered to women who later did not achieve pregnancy (P < .05). The expression of CD200 negatively correlates with the ratios of Th1/Th2 cytokines produced by female peripheral blood cells (P < .05) and positively correlates with the frequency of female circulating regulatory T cells after LIT (P < .05). The ROC analysis showed that the intensity of CD200 expression and the Th1/Th2 ratios are the significant predictors of pregnancy establishment after pre-gestational LIT (P < .05 and P < .01, respectively).

CONCLUSION

Elevated CD200 expression on allogeneic lymphocytes most likely suppresses the pro-inflammatory Th1-type immunity needed for successful embryo implantation. Therefore, a personalized approach of LIT should be applied to avoid negative effects of such immunomodulation on pregnancy establishment.

Decreased expression of CD200 and CD200R1 by human decidual tissues in spontaneous early abortion

Objective: To examine the cellular distribution and the expression of CD200 and its receptor 1 (CD200R1) in human deciduas in first-trimester pregnant women with spontaneous early abortion (SEA) and normal pregnancy, and to explore their role in the etiology of SEA.Subjects and methods: Thirty-five women at 6-10-week gestation with SA and 30 women of similar gestational age with a healthy pregnancy were recruited. Expression of CD200 and CD200R1 in the deciduas was determined using immunohistochemistry, confocal laser scanning microscope, Western blot, and real-time PCR (RT-PCR).Results: The decidual stromal cells, glandular epithelial cells, and vessel endothelial cells during the first trimester of pregnancy express both CD200 and CD200R1 proteins. During this period, the expression of CD200 in glandular epithelial cells and vessel endothelial cells is significantly higher in normal pregnancy than that in women with SEA (0.3079 ± 0.0674 versus 0.2735 ± 0.0515; 0.4077 ± 0.1366 versus 0.3249 ± 0.0993); the expression of CD200R1 in stromal cells, decidual stromal cells, glandular epithelial cells is significantly higher during normal pregnancy than SEA (0.2574 ± 0.0588 versus 0.2292 ± 0.0415; 0.3617 ± 0.1046 versus 0.2804 ± 0.0640). Western blot analysis showed an approximately 44% decrease in CD200R1expression in decidua in the SEA versus the controls. Finally, in decidua, the expression of both CD200 protein and CD200R1 transcript are significantly higher in healthy first-trimester pregnancy than in SEA (CD200: 2.2089 ± 1.2754 versus 0.7241 ± 0.2143; CD200R1: 15.7843 ± 10.7085 versus 7.3381 ± 5.8529).Conclusions: Women with SEA have a lower level of CD200 and CD200R1 expression in deciduas compared with normal pregnant women suggesting that under physiological conditions, CD200 and CD200R1 expression by deciduas is important to prevent fetal loss ensure a successful pregnancy.

Active Immunisation with Partner Lymphocytes in Female Patients Who Want to Become Pregnant - Current Status

Around 1 – 3% of all couples who try to have a child are affected by recurrent miscarriage. According to the WHO, recurrent miscarriage is defined as the occurrence of three or more consecutive miscarriages up to the 20th week of pregnancy. There are various causes of recurrent miscarriage; in many cases, the causes remain unclear, with the result that immunological factors are one of the possible causes discussed. For the motherʼs immune system, the embryo represents a semi-allogeneic transplant, as half of the embryoʼs genes are of paternal origin. In place of a conventional immune response, the embryo induces a secondary protection mechanism, which contributes to the successful implantation. When performing immunisation with partner lymphocytes, the patient receives an intradermal injection of her partnerʼs prepared lymphocytes into the volar side of the forearm in order to induce immunomodulation with a consequently increased rate of pregnancy and live birth. A prerequisite for this procedure is that all other possible causes of sterility have been ruled out in advance. Due to the highly heterogeneous nature of the data, a significant benefit as a result of the immunisation cannot yet be clearly proven. However, there are signs that the therapy may be effective when using lymphocytes that have been extracted as short a time beforehand as possible. Overall, the treatment represents a safe, low-risk procedure. Following a detailed informative discussion with the couple regarding the chances of success and following a detailed review of the indication and contraindications, immunisation with partner lymphocytes can be discussed with the couple on a case-by-case basis – provided that all other possible causes of sterility have been ruled out in advance.

Lymphocyte immunotherapy in the treatment of recurrent miscarriage: systematic review and meta-analysis

PURPOSE

Recurrent miscarriage (RM) affects up to 2-3% of couples of reproductive age. There are several causes for this condition, including immunologic. The embryo is considered an allograft, subject to the rejection mechanisms of the maternal immune system. Immunotherapy involving immunization with lymphocytes is considered in cases of idiopathic RM. However, there is still no consensus regarding the efficacy and safety of this therapy.

METHODS

This systematic review and meta-analysis evaluated the data available in the literature regarding the efficacy and safety of the use of immunotherapy with lymphocytes in couples with history of RM. Searches in PubMed/Medline, SCOPUS, and Cochrane Library databases were conducted, using the following keywords: "recurrent miscarriage," "lymphocyte immunotherapy," and "meta-analysis." Statistical analyses were performed using Review Manager 5.3 (RevMan), version 5.3.

RESULTS

Six published meta-analysis were retrieved; two found no improvements in the rate of live births after the use of immunization with lymphocytes in the treatment of RM, and four found a beneficial effect of the use of immunotherapy with lymphocytes in cases of RM, with significant improvements in the rate of live births.

CONCLUSION

Data available in the literature supports the efficacy and safety of immunotherapy with lymphocytes in cases of RM without an identified cause.

Microchimerism in recurrent miscarriage

Maternal-fetal cell exchange during pregnancy results in acquisition of microchimerism, which can durably persist in both recipients. Naturally acquired microchimerism may impact maternal-fetal interaction in pregnancy. We conducted studies to ask whether microchimerism that a woman acquired from her own mother is detectable before or during pregnancy in women with recurrent miscarriage. Fetal microchimerism was also assayed. Women with primary idiopathic recurrent miscarriage (n=23) and controls (n=31) were studied. Genotyping was conducted for probands, their mothers and the fetus, a non-shared polymorphism identified and quantitative polymerase chain reaction performed to measure microchimerismin peripheral blood mononuclear cells. Preconception comparisons were made between recurrent miscarriage subjects and controls, using logistic regression and Wilcoxon rank sum. Longitudinal microchimerism in subsequent pregnancies of recurrent miscarriage subjects was described. There was a trend toward lower preconception detection of microchimerism in recurrent miscarriage versus controls, 6% vs. 19% (1/16 vs. 6/31, P=0.2). During pregnancy, 3/11 (27%) of recurrent miscarriage subjects who went on to have a birth had detection of microchimerism from their own mother, whereas neither of two subjects who went on to miscarry had detection (0/2). This initial data suggest that microchimerism from a woman's own mother, while detectable in women with recurrent miscarriage, may differ from controls and according to subsequent pregnancy outcome. Further studies are needed to determine the cell types, quantities and any potential functional role of microchimerism in recurrent miscarriage.

Reduced CD200 and CD200R1 expression in human chorionic villi contributes to early spontaneous abortion

OBJECTIVE

To examine the expression of CD200 and its receptor (CD200R) in human chorionic villi during the first trimester of normal pregnancy and early spontaneous abortion (ESA).

DESIGN

Prospective study.

METHODS

Expression of CD200 and CD200R in the chorionic villi was determined using streptavidin-peroxidase immunohistochemistry, confocal laser scanning microscopy and real-time polymerase chain reaction.

POPULATION

Thirty-five women diagnosed with ESA and 30 women experiencing a healthy pregnancy in a medical university hospital in China were enrolled in this study between 2011 and 2013.

MAIN OUTCOME MEASURES

CD200 and CD200R expression.

RESULTS

The expression of CD200 in syncytiotrophoblast cells was significantly higher during normal pregnancy than in ESA (0.51 ± 0.05 vs. 0.35 ± 0.05). In contrast, expression of CD200 in cytotrophoblast cells and CD200R in stromal cells was significantly lower during normal pregnancy when compared with ESA (CD200: 0.16 ± 0.02 vs. 0.32 ± 0.03; CD200R: 0.19 ± 0.03 vs. 0.22 ± 0.02). In villi, the expression of both CD200 protein and CD200R transcripts were significantly higher in healthy first-trimester pregnancy than in ESA (CD200: 156.89 ± 105.65 vs. 37.51 ± 17.62).

CONCLUSIONS

There is an increase in inhibitory properties of human chorionic villi during normal pregnancy. The mechanism underlying ESA might be associated with enhanced expression of CD200 and CD200R in the trophoblast, leading to an upregulation of the immune response during the first trimester of pregnancy.

The CD200-tolerance signaling molecule associated with pregnancy success is present in patients with early-stage breast cancer but does not favor nodal metastasis

PROBLEM

The CD200-tolerance signaling molecule prevents pregnancy failure and is also expressed by a wide variety of malignant tumors. The effect of CD200 mRNA expression on progression of human tumors has been variable.

METHOD OF STUDY

A cross-sectional study was performed to examine the correlation between CD200 protein expression in the primary tumors from postoperative Stage I-IIIA human breast cancer and the likelihood of regional lymph node metastasis.

RESULTS

Fifty-eight percentage of patients had strong CD200(+) tumor staining (71% of Stage I and 53% Stage II-IIIA). Strong staining was associated with large T2-3 primary tumors compared to T1 tumors (64 versus 50%) and T2-3 N(+) versus T1 N(-) tumors (70 versus 63%), but this was not statistically significant. Nodal metastases were not more frequent in patients with strong CD200(+) staining (57% compared to 58% for weak/negative staining cases), and the metastatic tumor cells in regional lymph nodes were often CD200(-) when the primary tumor was CD200(+).

CONCLUSION

CD200 expression by early-stage human breast cancer cells in primary tumors did not correlate with increased regional lymph node metastasis.

Progesterone-mediated immunomodulation in pregnancy: its relevance to leukocyte immunotherapy of recurrent miscarriage

Progesterone is crucial for the establishment and maintenance of pregnancy. Progesterone-regulated genes in the pregnant uterus control the development of endometrial receptivity as well as recruitment and differentiation of decidual NK cells, which in turn act on angiogenesis and trophoblast invasion. The link between progesterone and the immune system is established by lymphocyte progesterone receptors expressed in peripheral blood gammadelta T cells of pregnant women and in peripheral NK cells. Regulation of lymphocyte progesterone receptors is activation related, thus efficient recognition of fetal antigens is a requirement for the initiation of progesterone-dependent immunoregulatory mechanisms. Several immunological effects of progesterone are mediated by progesterone-induced blocking factor--the product of a progesterone-induced gene in lymphocytes. One part of unexplained recurrent miscarriages might have an immunological etiology. Immunization of the mothers with paternal or third-party leukocytes aims to correct the misregulated antifetal immune response. There are, however, serious concerns about this treatment, including the lack of information about the mode of action and possible adverse effects of the treatment, the failure to detect a significant effect of immunotherapy and the lack of a reliable generally accepted marker for patient selection. These concerns will be discussed in this review.