Comprehensive Analysis of Peripheral Blood Lymphocytes in 76 Women with Recurrent Miscarriage before and after Lymphocyte Immunotherapy

Impact of body mass index on peripheral and uterine immune status in the window of implantation in patients with recurrent reproductive failure

This study aimed to investigate whether maternal obesity affects the immune status of peripheral blood and endometrium in patients with recurrent reproductive failure classified according to their body mass index (BMI). A total of 228 repeated implantation failure (RIF) and 266 recurrent miscarriage (RM) patients were enrolled in the study and further subdivided into three groups according to their BMI: (i) normal weight (18.5≤ BMI <23); (ii) overweight (23≤ BMI <25); and (iii) obese (BMI ≥25). Peripheral blood and endometrium samples were collected in the mid-luteal phase before IVF treatment or natural pregnancy. Peripheral immunocytes were analyzed by flow cytometry, while uterine immune cells were subjected to immunohistochemistry. In RM patients, significantly increased peripheral helper T cells and decreased cytotoxic T cells, NK cells were observed in the obese group compared with the normal-weight group. Meanwhile, in the endometrium, the percentage of NK cell, macrophage cell, M2 macrophage cell, and Treg cell significantly reduced with increased BMI in RIF patients, and the percentage of NK cell and M2 macrophage cell significantly decreased with increased BMI in RM patients. In conclusion, obesity may cause endometrial immune disorder in recurrent reproductive failure women, but was only associated with the peripheral immune change in RM patients.

The effect of lymphocyte immunotherapy (LIT) in modulating immune responses in patients with recurrent pregnancy loss (RPL)

In order to prevent miscarriage in RPL patients, the goal of this study was to determine how well lymphocyte immunotherapy (LIT) works in modifying immunological responses produced by cells, cytokines, transcription factors, and microRNAs. 200 RPL patients and 200 healthy controls were included in the study. Using flow cytometry, it was possible to compare the frequency of cells before and after lymphocyte treatment. Real-time PCR was used to assess the gene expression levels of transcription factors, cytokines, and microRNAs. ELISA method was used to evaluate the level of secretion of cytokines in the serum. Primary evaluation of the immune profile between healthy controls and RPL cases showed a higher frequency of Th17, NK, B cells and a lower frequency of Treg cells in RPL cases. Also, pro-inflammatory cytokines showed increased expression at mRNA and protein levels in the RPL group in comparison with the control group. Whereas, anti-inflammatory cytokines showed decreased expression in RPL patients. Decreased and increased frequency of Th17 and Treg lymphocytes observed in RPL cases following LIT, respectively. The same results obtained for RORγt and FoxP3 mRNA expression as transcription factor of Th17 and Treg cells, respectively. NK cell cytotoxicity decreased after LIT in RPL patients. miR-326a and miR-155 expression after LIT reduced, but miR-146a and miR-10a expression increased in RPL instances. LIT in RPL cases causes to elevation and modulation of anti-inflammatory and pro-inflammatory cytokines. Our data showed that lymphocyte therapy can be proposed as an effective therapeutic agent in RPL patients with immunological background by a modulating inflammatory condition.

Peripheral blood natural killer cell cytotoxicity in recurrent miscarriage: a systematic review and meta-analysis

Dysregulated natural killer (NK) cells have been associated with recurrent miscarriages (RM). Studies have suggested that high peripheral blood NK cell cytotoxicities (pNKCs) are associated with an increased risk of RM. The aim of this systematic review (SR) and meta-analysis (MAs) is to investigate the difference in pNKC between nonpregnant and pregnant women with RM and controls and determine whether pNKC is reduced by immunotherapy. We searched the PubMed/Medline, Embase, and Web of Science databases. The MAs were conducted to compare pNKCs between women with and without RM before and during pregnancy as well as pre- and post-immunotherapy. Risk of bias in nonrandomized studies was assessed by the Newcastle-Ottawa Scale. Statistical analysis was performed using the Review Manager software. A total of 19 studies were included in the SR and 14 studies in the MAs. The MAs revealed higher pNKCs among nonpregnant women with RM compared to controls (MD, 7.99 95 %CI 6.40-9.58; p < 0.00001). pNKCs were also higher in pregnant women with RM than in pregnant controls (MD, 8.21 95 %CI 6.08-10.34; p < 0.00001). Women with RM showed significantly decreased pNKCs after the immunotherapy compared to before (MD, -8.20 95 %CI -10.20 - -6.19; p < 0, 00001). Additionally, there is an association between high pNKCs and the risk of pregnancy loss in women with RM. However, included studies showed substantial heterogeneities regarding the inclusion criteria of patients, techniques measuring pNKC, and types of immunotherapies. More studies are needed to evaluate the clinical efficiency of pNKCs in managing RM.

Contradictory Effect of Lymphocyte Therapy and Prednisolone Therapy on CD3+CD8+CD56+ Natural Killer T Population in Women with Recurrent Spontaneous Abortion

Background

Natural killer T (NKT) cells are influential immune cells in pregnancy failures, including recurrent spontaneous abortion (RSA). Different approaches are used for these disorders due to their effects on maternal immunomodulation.

Aims

In the present study, we compared the effects of two typical immunotherapies (lymphocyte immunotherapy [LIT] and low-dose prednisolone) on CD3+CD56+CD16+ and CD3+CD56+CD8+ cells as two distinct subsets of NKT cells in Women with RSA.

Settings and Design

This study was a comparative cohort study conducted from 2021 to 2022. One hundred and five women with RSA were distributed into three treatment groups randomly.

Materials and Methods

Fifty women in the group of low-dose prednisolone therapy, fifty women in the LIT group and five women without any treatment as the control group were included in the study. NK and NKT cell subsets were assessed using flow cytometry. Furthermore, the concentration of interferon-gamma (IFN-γ), transforming growth factor-beta (TGF-β) and interleukin-10 (IL-10) was measured quantitatively using the enzyme-linked immunosorbent assay technique.

Statistical Analysis Used

Normality and comparisons between study groups were performed by non-parametric unpaired Mann-Whitney, Kruskal-Wallis rank sum test, and one-way ANOVA.

Results

The percentage of CD56dim NK cells was increased after prednisolone therapy, while this population significantly decreased in the LIT group. In contrast to the LIT group, the administration of prednisolone increased CD3+CD8+CD56+ NKT cells (P < 0.0001), which is helpful for pregnancy. The effect of the investigated treatment approaches on the population of peripheral CD3+CD56+CD16+ NKT cells of women with RSA was not adequately significant. The same situation was also observed regarding the serum level of IFN-γ. However, a significant decrease in serum levels of IL-10 and TGF-β was observed after prednisolone therapy.

Conclusion

The lower capability of LIT in changing the population of NKT cells compared to prednisolone therapy may be due to its mechanism of action, which is related to the production of blocking antibodies. These treatment approaches had different effects on NKT cells, indicating that NKT cell population and function can be affected using LIT and prednisolone therapy distinctly. In addition, prednisolone therapy and LIT in women with normal serum levels of IFN-γ have no harmful effects in changing the production of this critical cytokine.

Blood CD4+CD25+ T regulatory cells constitute a potential predictive marker of subsequent miscarriage in unexplained recurrent pregnancy loss

The aim of this study was to investigate the relationship between pre-pregnancy blood immune status and unexplained recurrent pregnancy loss (URPL), and to evaluate the predictive value of pre-pregnancy blood Treg levels for subsequent miscarriage in patients with URPL. We retrospectively analyzed 76 women who had experienced two or more miscarriages before 24 weeks of gestation for no obvious reason, and 74 women who had achieved live births as controls. Flow-cytometric analysis of peripheral blood CD4 + T cells, CD8 + T cells, NK cells, NKT cells, B cells, NK cell subpopulations (including CD56^bright NK cells, CD56^dim NK cells, CD56^dimCD16⁺ NK cells, and CD56^brightCD16^- NK cells) was executed in the luteal phase of women in the URPL and control groups. When we reviewed and analyzed reproductive outcomes in URPL patients, we found that blood Tregs were significantly lower in the URPL group than in the controls (1.89% ± 0.61% vs. 2.15% ± 0.58%, P < 0.01) during the luteal phase pre-pregnancy. However, we discerned no differences among blood CD4⁺T cells, CD8⁺T cells, B cells, NKT cells, or NK cells, NK subpopulations (CD56^bright NKs, CD56^dim NKs, CD56^dimCD16⁺ NKs, or CD56^brightCD16^- NKs) between the two groups. By implementing receiver operating characteristic (ROC) curve analysis to determine whether Treg levels predicted subsequent miscarriages, we found that the area under the ROC curves was 0.714, and that the cutoff value was 1.35, with a sensitivity of 0.556 and specificity of 0.923. Based on the cutoff value, we divided pregnant URPL patients into two groups, demonstrating that the subsequent miscarriage rates in the low-Treg level group (<1.35%) were significantly higher than those in the normal-Treg level group (>1.35%) (71.43% vs. 14.29%, P < 0.01). CONCLUSION: The pre-pregnancy blood Treg level was a potential marker that predicted subsequent miscarriage in women with URPL.

The Impact of New Immunological Therapeutic Strategies on Recurrent Miscarriage and Recurrent Implantation Failure

Maternal-fetal immune dysregulation is one of the risk factors that increases the probability of embryo rejection and reproductive failure. The stimulation of immunological tolerance and suppression of immunological rejection are prerequisites for protecting embryos and preventing immunological attacks. Hence, it appears that immunomodulatory and immunosuppressive therapies can manage reproductive failures by controlling immune cells. The current medical literature has shown that immunotherapy approaches and cell therapy have promising results in improving pregnancy outcomes and live birth rates. These outcomes are obtained by regulating maternal immune responses, and exerting positive effects on human reproductive processes.

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.

Functional significance of lymphocytes in pregnancy and lymphocyte immunotherapy in infertility: A comprehensive review and update

During pregnancy, the fetal-maternal interface underlies several dynamic alterations to permit the fetus to be cultivated and developed in the uterus, in spite of being identifies by the maternal immune system. A large variety of decidual leukocyte populations, including natural killer cells, NKT cells, innate lymphoid cells, dendritic cells, B cells, T cells, subpopulations of helper T cells play a vital role in controlling the trophoblast invasion, angiogenesis as well as vascular remodeling. In contrast, several regulatory immunosuppressive mechanisms, including regulatory T cells, regulatory B cells, several cytokines and mediators are involved in maintain the homeostasis of immune system in the fetal-maternal interface. Nonetheless, aberrant alterations in the balance of immune inflammatory or immunosuppressive arms have been associated with various pregnancy losses and infertilities. As a result, numerous strategies have been developed to revers dysregulated balance of immune players to increase the chance of successful pregnancy. Lymphocyte immunotherapy has been developed through utilization of peripheral white blood cells of the husband or others and administered into the mother to confer an immune tolerance for embryo's antigens. However, the results have not always been promising, implying to further investigations to improve the approach. This review attempts to clarify the involvement of lymphocytes in contributing to the pregnancy outcome and the potential of lymphocyte immunotherapy in treatment of infertilities with dysregulated immune system basis.

Low-dose lymphocyte immunotherapy rebalances the peripheral blood Th1/Th2/Treg paradigm in patients with unexplained recurrent miscarriage

BACKGROUND

The published results regarding lymphocytes immunotherapy for unexplained recurrent miscarriage (uRM) patients are conflicting due to different screening criteria and therapeutic protocols. The objective of the present study is to evaluate the effectiveness of immunotherapy using low-dose lymphocytes in patients with uRM and Th1/Th2/Treg paradigm disorders.

METHODS

Sixty-four uRM patients who received low-dose lymphocytes immunotherapy served as the immunotherapy group, while the other 35 women who did not receive the treatment served as the control group. The proportions of peripheral blood Th1 cells, Th2 cells and Treg cells; and the concentration of TGF-β1 in serum were detected by flow cytometry and enzyme-linked immunosorbent assay (ELISA), respectively, before and after the immunotherapy.

RESULTS

The proportion of Th1 cells was significantly decreased while the proportions of Th2 cells and Treg cells were significantly increased in immunotherapy group patients after treatment. In addition, the concentration of TGF-β1 in serum was significantly higher after immunotherapy than before. Forty-three uRM patients achieved pregnancy after receiving immunotherapy and 5 patients underwent miscarriages in the immunotherapy group (11.6%, 5/43), while 8 of the 23 pregnant patients experienced a miscarriage in the control group (34.8%, 8/23; p < 0.05).

CONCLUSIONS

Low-dose lymphocyte immunotherapy is beneficial for restoring balance in the Th1/Th2/Treg paradigm and improving pregnancy outcome in uRM patients.

TRIAL REGISTRATION

NCT03081325 . ClinicalTrials.gov . Retrospectively registered July 2015.

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.

What is the impact of SOCS3, IL-35 and IL17 in immune pathogenesis of recurrent pregnancy loss?

OBJECTIVE

To investigate the plasma levels of interleukin-4 (IL-4), IL-6, IL-10, tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), transforming growth factor-beta (TGF-beta), IL-17, IL-35 and suppressor of cytokine signaling 3 (SOCS3) in the women with history of idiopathic recurrent pregnancy loss (RPL) and in the fertile controls.

METHODS

This study was conducted with 60 idiopathic RPL cases and 40 age-matched fertile controls. Mid-follicular plasma levels of IL-17, IFN-gamma, TNF-alpha, TGF-beta, IL-6, IL-4, IL-10, SOCS3 and IL-35 were assayed by an enzyme linked immunosorbent assay.

RESULTS

The mean age of RPL and control cases were 31.6 ± 0.6 and 32.1 ± 0.7 years, respectively. While plasma IL-35 and SOCS3 levels of RPL group were significantly lower than that of the control group; IFN-gamma, TNF-alpha, IL-4, IL-6, IL-10, IL-17 and TGF-beta levels of RPL group were significantly higher than that of the control group. The comparison of cytokine ratios between RPL and control groups indicated significantly high TNF-alpha/IL-10, TNF-alpha/IL-4, IFN-gamma/IL-10, IFN-gamma/IL-6 and IFN-gamma/IL-4 ratios in the RPL group. IL-35/IL-17 ratio was significantly low in the RPL group compared to that in the control group. Overstimulation of TNF-alpha presented moderate influence on recurrent miscarriage risk.

CONCLUSION

Decreased SOCS3 and IL-35 plasma levels and increased Th1/Th2 cytokine ratios in RPL cases pointed out the supression of anti-inflammatory process and this supression might play an important role in the pathogenesis of idiopathic RPL.

Correlation between serum zinc levels and successful immunotherapy in recurrent spontaneous abortion patients

BACKGROUND:

Immunotherapy with paternal lymphocytes plays an important role in preventing recurrent spontaneous abortion (RSA) and is an effective treatment for it. This kind of treatment is performed as an immunotherapy method in several centers in the world. It attributes to the production of anti-paternal cytotoxic antibodies (APCAs) in women with RSA. Production of APCA after lymphocyte immunotherapy (LIT) in RSA patients gives them a better chance for successful pregnancy. Regarding the important effect of trace elements on the function of the immune system, we tried to investigate the correlation between serum zinc level and the success of LIT in RSA.

MATERIALS AND METHODS:

Serum zinc concentration was determined in two groups of RSA patients using atomic absorption spectrophotometer systems. Group (a) that responded to the paternal lymphocytes and their cross-match test was positive, and group (b) that had no response to the paternal lymphocytes immunizations and their cross-match test was negative.

RESULTS:

Serum zinc levels in group (a) patients were 74.98 ± 11.88 μg/dl, which was significantly higher than those in group (b) with the zinc concentration of 64.22 ± 9.22 μg/dl.

CONCLUSIONS:

Zinc deficiency may be one of the substantial causes of negative results for LIT in RSA patients. Therefore, compensation of zinc defect before LIT can be a promising approach to improve the immune response in patients.

Increased maternal cytokine production and congenital heart defects

Congenital heart defects (CHDs) are a major cause of infant mortality. Most CHDs are thought to result from genetic, lifestyle, and environmental factors that include maternal obesity, diabetes, toxicant exposure, and alterations in anti-oxidant capacity. Since these well-documented risk factors are also associated with immune dysregulation, we sought to compare the maternal immune response in mothers carrying a fetus with a CHD with those mothers whose pregnancies were not affected by any birth defect. We conducted a case-control study to examine the maternal cytokine profile using multiplex technology in pregnant mothers (subject mean=26 weeks' gestation). This investigation revealed that whole blood cultures derived from case mothers produced higher levels of certain cytokines and chemokines compared with cultures from control subjects when activated with mitogen. Cultures from case subjects produced higher levels of IL-10, IL-13, IL-4, IL-5, IL-17, and IL-6, when stimulated with mitogen compared with control subjects. Plasma levels of chemokine MIP-1α were higher in cases compared with controls. In contrast, C-reactive protein levels were not statistically different. These results demonstrate the need to further examine the maternal cytokine signature in CHD-affected pregnancies. This information could pave the way toward maternal immunotherapeutic intervention to prevent CHDs, and novel biomarker discovery to improve pre-natal diagnosis.