Innate and adaptive immune dysregulation in women with recurrent implantation failure.

Recurrent implantation failure (RIF) is a condition where a woman fails to obtain pregnancy after multiple embryo transfer cycles, even with superior-quality blastocysts. There are various factors that can contribute to RIF, including immunologic disturbances. The immune system is extremely important during pregnancy. Immune cells such as T cells, B cells, natural killer (NK) cells, and macrophages (MQ) are present in the female reproductive tract and are accountable for regulating the immune response to invading pathogens and maintaining tissue homeostasis. Dysregulation of these immune cells can lead to inflammation, which can impair fertility. One of the most common immunological disturbances observed in RIF is an altered Th1/Th2 ratio, along with changes in NK cell and macrophage numbers. In addition, the presence of some antibodies, such as anti-ovarian antibodies, can also contribute to RIF. Interleukins have been implicated in the development of an inflammatory response that can interfere with successful embryo implantation. As a result, a comprehensive understanding of immunological compartments in RIF women could assist us in determining the immunological origins of this disease. We will discuss immunological factors that might contribute to RIF etiology, including cellular and molecular components.

Cytokine and chemokine profiles in women with endometriosis, polycystic ovary syndrome, and unexplained infertility.

Numerous factors (including immunological, congenital, hormonal, and morphological disorders) can lead to infertility. In this regard, 3 specific diseases associated with infertility are discussed in this review study (i.e., polycystic ovary syndrome [PCOS], endometriosis [EMS], and unexplained infertility [UI]). PCOS is a common endocrine disorder characterized by chronic low-grade inflammation, and EMS is a benign disease characterized by the presence of ectopic endometrial tissue. UI refers to couples who are unable to conceive for no known reason. Conception and pregnancy are significantly affected by the immune system; in this regard, chemokines and cytokines play important roles in the regulation of immune responses. Patients with PCOS, EMS, and UI have altered cytokine and chemokine profiles, suggesting that dysregulation of these molecules may contribute to infertility in these conditions. Accordingly, the issue of infertility is addressed in this review study, a condition that affects approximately 16% of couples worldwide.

Increased frequency of CD39+CD73+ regulatory T cells and Deltex-1 gene expression level in kidney transplant recipients with excellent long-term graft function.

BACKGROUND: The ability of regulatory T cells (Tregs) to limit inflammatory responses has been demonstrated. However, different subpopulations of this cell have varying abilities to suppress alloreactive immune responses. The primary goal of this study was to assess the frequency of CD4+FOXP3+CD39+CD73+ Tregs and Deltex-1 gene expression on long-term renal transplant function. METHODS: A total of 49 subjects were divided into 3 groups: (i) the excellent long-term graft function (ELTGF) group, (ii) the chronic graft dysfunction (CGD) group, and (iii) the healthy control (HC) group. Following sample collection, peripheral blood mononuclear cells (PBMCs) were isolated, and the Deltex-1 gene expression level and the frequency of CD4+FOXP3+CD39+CD73+ Tregs were evaluated. RESULTS: The ELTGF group had more CD4+FOXP3+ Tregs than the CGD group, but the difference was not statistically significant (P = 0.07). However, the frequency of CD4+FOXP3+CD39+CD73+ Tregs and the ratio of these cells to total CD4+ lymphocytes significantly increased in the ELTGF group than in the CGD group (P = 0.04 and P = 0.02 respectively). In addition, the expression level of the Deltex-1 gene was significantly lower in the CGD group than in the other 2 groups (P = 0.01 and P = 0.04 respectively). CONCLUSIONS: Given the increased frequency of CD4+FOXP3+CD39+CD73+ Tregs and the expression level of the Deltex-1 gene in the ELTGF group, it appears that these factors probably improved function and long-term survival of the transplanted organ through the suppression of alloreactive responses and reduction of inflammation. In other words, one of the immunological mechanisms involved in the CGD group may be a deficiency in Tregs.

Decreased frequency of regulatory T cells and level of helios gene expression in secondary progressive multiple sclerosis patients: Evidence about the development of multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is an aggressive disease characterized by central nervous system (CNS) inflammatory and demyelinating lesions. Tolerance failure is implicated in the development of several autoimmune disorders, including MS. Due to their involvement in maintaining environmental tolerance, regulatory T cells (Tregs) are regarded as efficient immune cells. We examined the frequency of Tregs in this study using CD4/CD25/forkhead box protein P3 (FOXP3)/Helios markers. METHODS: Fifty participants, including 25 patients with secondary progressive MS (SPMS) and 25 healthy controls (HCs), were enrolled in this study, and their demographic characteristics were recorded. Peripheral blood samples ranging from 5 to 6 mL were obtained, and the Ficoll technique was used to extract peripheral blood mononuclear cells (PBMCs). Then, the percentage of CD4+CD25+FOXP3+Helios+ regulatory T lymphocytes was examined by flow cytometry in the study groups. Real-time polymerase chain reaction (PCR) was also used to assess the Helios gene expression level. RESULTS: This study showed that the percentage of Tregs with CD4 and CD25 markers did not reveal a significant difference compared with HCs despite the decrease in SPMS patients (P = 0.6). However, lymphocytes with CD4/CD25/FOXP3/Helios markers were significantly reduced in the patients (P = 0.01). Additionally, SPMS patients had statistically significantly lower Helios gene expression levels (P = 0.002). CONCLUSION: In SPMS patients, a decrease in the frequency of the CD4+CD25+FOXP3+Helios+ Treg population can result in an imbalanced immune system. In other words, one of the immunological mechanisms involved in this disease may be a deficiency in Tregs. Helios gene expression was also decreased in these patients, which may exacerbate functional defects in Tregs.

Pronounce expression of Tim-3 and CD39 but not PD1 defines CD8 T cells in critical Covid-19 patients.

BACKGROUND: During viral infection, inhibitory receptors play a key role in regulating CD8 T-cell activity. The objective of this research was to investigate programmed cell death protein 1 (PD-1), T-cell immunoglobulin and mucin domain-containing protein-3 (TIM-3), and CD39 exhaustion markers in CD8 T cells of new coronavirus disease-2019 (COVID-19) patients. METHODS: A total of 44 patients with COVID-19 (17 subjects in a critical group and 27 patients in a non-critical group) and 14 healthy controls, who were admitted to Hospitals in Babol, were recruited to the study. In subjects' peripheral blood mononuclear cells (PBMCs), we compared the phenotype of CD8 T lymphocytes, expressing PD-1, TIM-3, or CD39, both alone and in various combinations. RESULTS: The findings showed that the percentage of CD8+ cells was significantly lower in patients. Critical and non-critical patients were more likely than healthy controls to have an escalated frequency of CD8+ TIM-3+, CD8+ CD39+, and CD8+ TIM-3+ CD39+ cells. No significant differences were observed between all groups in the CD8+ PD-1+ cell counts. There was also no difference between three groups regarding the counts of CD8+ TIM-3+ PD-1+, CD8+ PD-1+ CD39+, and CD8+ TIM-3+ PD-1+ CD39+ cells. The counts of non-exhausted cells were significantly lower in critical and non-critical individuals compared to the healthy individuals' value. CONCLUSION: Patients, infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), altered exhausted CD8 T lymphocytes with CD39 and TIM-3 exhaustion markers, which may account the dysregulated immune response found in COVID-19.

Decreased Frequency of CD8+HLA-G+ T Cell in the Peripheral Blood of Primary Unexplained Infertile Females.

Most of the findings have focused on the importance of CD4+HLA-G+ and CD8+HLA-G+ regulatory T cells (Treg) during pregnancy. It has been demonstrated that these HLA-G+ T cell subsets could induce maternal immune tolerance against semi-allogenic conceptus during pregnancy. There are only a few experiments regarding the Treg cells in the context of unexplained infertility (UI). Thirty-five participants including 18 primary unexplained infertile and 17 fertile females were enrolled in this study. A total of 3-5 ml blood samples were taken, and peripheral blood mononuclear cells (PBMCs) were separated by using Ficoll. Using a flow cytometer, the frequency of CD4+HLA-G+ and CD8+ HLA-G+ T cells was assessed in the peripheral blood samples of primary unexplained infertile and fertile females. Our results showed that the frequency of CD8+HLA-G+ Treg cells was significantly lower in primary unexplained infertile females than fertile females (P = 0.048). Although the frequency of CD4+HLA-G+ Treg cells in the primary unexplained infertile females was lower than fertile females, the difference was not statistically significant (P = 0.25). Regarding the important role of CD8+HLA-G+ Treg cells during pregnancy and its decrease in females with primary UI, it seems that reduced CD8+ HLA-G+ Treg cells could be a leading immunological factor in the context of infertility. Nevertheless, more researches are needed in this field.

Under-expression of microRNA-146a and 21 and their association with Crohn's disease.

MicroRNAs (miRNAs) can post-transcriptionally regulate gene expression and are involved in the immune response. Excessive immune response to the gut microbiota plays a major role in the pathogenesis of Crohn's disease (CD). Regarding the role of miRNAs in immune response, this study aimed to investigate the contribution of miRNAs in the pathogenesis of CD. A total of 53 participants, including 23 CD patients and 30 healthy controls (HCs) were enrolled in this study. miRNAs, including miR-21, miR-29a, miR-29b, miR-31, miR-146a, miR-155, miR-181a, and miR-181c were evaluated via TaqMan MicroRNA Assays. Among the eight miRNAs, the amounts of miR-146a and miR-21 were significantly decreased in the CD patients relative to HC subjects. Moreover, we showed that there was a negative correlation between miR-146a and Harvey-Bradshaw index (HBI), as well as a positive correlation of miR-21 and miR-29b with HBI. Under-expression of miR-146a and miR-21, which are critical for the regulatory function of regulatory T cells (Tregs), is remarkably associated with CD.

Soluble CD30, the Immune Response, and Acute Rejection in Human Kidney Transplantation: A Systematic Review and Meta-Analysis.

Soluble CD30 (sCD30) is considered to be a marker for the activated immune system in which T cells can damage the allograft. Some studies reported that post-transplant sCD30 can predict early acute rejection and can thereby be used as a biomarker to detect acute rejection. However, several other studies found no relation between post-transplant sCD30 and acute rejection. This meta-analysis study aims to answer this main question of whether sCD30 can help clinicians to monitor transplant recipients. The electronic databases, including PubMed, Web of Science, ProQuest, Embase, Scopus, Google Scholar, the gray literature, and the key journals, were searched for observational studies from 1 January 1990 up to 30 April 2018. Eighteen studies, with a total of 1,453 patients, were included in this paper. With regard to the different measurement times, post-transplant sCD30 was separately analyzed and divided into five groups (i.e., 1, 2, 3, 4 week, and 1 month post-transplant sCD30). All groups indicated a strong association between sCD30 and the acute rejection. The standardized mean difference (SMD) is 1.22 in 1 week, 0.77 in 2 week, 1.11 in 3 week, 1.27 in 4 week, and 0.71 in 1 month groups. The association between sCD30 and acute rejection was consistent across all the subgroup analyses. We found that post-transplant sCD30 had a strong association with acute kidney rejection. We also found that the deceased donors had more association with the high amount of sCD30 than living donors in patients with acute rejection. Finally, we realized that donor type was an important factor leading to the heterogeneous results in the primary studies.

The exosome as a novel predictive/diagnostic biomarker of rejection in the field of transplantation.

Finding a non-invasive biomarker to monitor allograft status after transplantation could contribute to better control of the post-transplant status of transplant recipients and, if possible, could be used instead of invasive biopsy for proving rejection. On the other hand, reducing the dosage of immunosuppression or stopping lifelong use of them because of their severe side effects is an important goal in order to dispose of their severe side effects. The ability of exosomes as a biomarker of rejection and as a therapeutic strategy was investigated in the human kidney, heart, and lung transplantation or in transplantation models with interesting results. Moreover, the ability of exosome was assessed as antigen-presenting vesicles (APVs), in which exosomes can either participate in immune stimulation (semi-direct recognition) or immune suppression thereby, influence on the transplantation outcome. In this paper, authors try to provide comprehensive information about triple role of exosomes in the transplantation medicine.

TIM-3 as a marker of exhaustion in CD8+ T cells of active chronic hepatitis B patients.

BACKGROUND: Chronic HBV infection presents weak or no virus-specific T-cell responses, implying to an exhausted phenotype, characterized by overexpression of several inhibitory receptors. In the present study, it was aimed to characterize the panel of inhibitory molecules on the CD8+ T cells in patients with active chronic HBV infection. METHODS: In this study, 31 active and 32 inactive individuals with chronic HBV infection were recruited. Peripheral blood mononuclear cells were isolated and a multicolor flow cytometry was applied to evaluate the surface inhibitory molecules of TIM3, PD-1, and CD39. RESULTS: CD8+ T cells expressing TIM3 were significantly higher in cases with active chronic HBV infection compared to inactive chronic HBV group (8.43 ±â€¯1.4 vs. 5.15 ±â€¯1.43; P < 0.0001). CD8+TIM3+PD-1+ T cells were significantly higher in active chronic HBV cases in comparison to the inactive chronic HBV subjects (4.26 ±â€¯1.04 vs. 3.41 ±â€¯0.74; P < 0.001). Different subpopulations of the CD8+ T cells were correlated with the duration of infection and HBV DNA load in the cases with active chronic HBV infection. CONCLUSION: It appears that CD8+ TIM3+ T cells are the major exhausted phenotype of T cells during the active state of HBV infection.

T cell exhaustion implications during transplantation.

Exhaustion of lymphocyte function, particularly T cell exhaustion, due to prolonged exposure to a high load of foreign antigen is commonly seen during chronic viral infection as well as antitumor immune responses. This phenomenon has been associated with a determined molecular mechanism and phenotypic manifestations on the cell surface. In spite of investigation of exhaustion, mostly about CD8 responses toward viral infections, recent studies have reported that chronic exposure to antigen may develop exhaustion in CD4 + T cells, B cells, and NK cells. Little is known with respect to lymphocyte exhaustion during transplantation and its effect on aberrant anti-graft responses. Through a same mechanobiology observed during chronic exposure of foreign viral antigens, alloantigen persistence mediated by allograft could develop a favorable circumstance for exhaustion of T cells responding to allograft. However, to achieve better manipulation approaches of this event to reduce the complications during transplantation, we need to be armed with a bulk of knowledge with regard to quality and quantity of T cell exhaustion occurring in various allografts, the kinetics of exhaustion development, the impression of immunosuppressive agents on the exhaustion, and the influence of exhaustion on graft survival and immune tolerance.

Immunological comparison of DNA vaccination using two delivery systems against canine leishmaniasis.

Visceral leishmaniasis (VL) is a fatal disease caused by the intracellular protozoan parasite Leishmania infantum. Dogs are the primary reservoirs of this parasite, and vaccination of dogs could be an effective method to reduce its transfer to humans. In order to develop a vaccine against VL (apart from the choice of immunogenic candidate antigens), it is necessary to use an appropriate delivery system to promote a proper antigen-specific immune response. In this study, we compared two vaccine delivery systems, namely electroporation and cationic solid-lipid nanoparticle (cSLN) formulation, to administer a DNA vaccine containing the Leishmania donovani A2 antigen, and L. infantum cysteine proteinases of type I (CPA) and II (CPB) without its unusual C-terminal extension. The protective potencies of these two vaccine delivery systems were evaluated against L. infantum challenge in outbred dogs. Our results show that the administration of pcDNA-A2-CPA-CPB(-CTE)GFP vaccine as a prime-boost by either electroporation or cSLN formulation protects the dogs against L. infantum infection. Partial protection in vaccinated dogs is associated with significantly (p<0.05) higher levels of IgG2, IFN-γ, and TNF-α and with low levels of IgG1 and IL-10 as compared to the control group. Protection was also correlated with a low parasite burden and a strong delayed-type hypersensitivity (DTH) response. This study demonstrates that both electroporation and cSLN formulation can be used as efficient vaccine delivery systems against visceral leishmaniasis.

Evaluation of Live Recombinant Nonpathogenic Leishmania tarentolae Expressing Cysteine Proteinase and A2 Genes as a Candidate Vaccine against Experimental Canine Visceral Leishmaniasis.

Canine Visceral Leishmaniasis (CVL) is a major veterinary and public health problem caused by Leishmania infantum (L. infantum) in many endemic countries. It is a severe chronic disease with generalized parasite spread to the reticuloendothelial system, such as spleen, liver and bone marrow and is often fatal when left untreated. Control of VL in dogs would dramatically decrease infection pressure of L. infantum for humans, since dogs are the main domestic reservoir. In the past decade, various subunits and DNA antigens have been identified as potential vaccine candidates in experimental animal models, but none has been approved for human use so far. In this study, we vaccinated outbreed dogs with a prime-boost regimen based on recombinant L. tarentolae expressing the L. donovani A2 antigen along with cysteine proteinase genes (CPA and CPB without its unusual C-terminal extension (CPB-CTE) and evaluated its immunogenicity and protective immunity against L. infantum infectious challenge. We showed that vaccinated animals produced significantly higher levels of IgG2, but not IgG1, and also IFN-γ and TNF-α, but low IL-10 levels, before and after challenge as compared to control animals. Protection in dogs was also correlated with a strong DTH response and low parasite burden in the vaccinated group. Altogether, immunization with recombinant L. tarentolae A2-CPA-CPB-CTE was proven to be immunogenic and induced partial protection in dogs, hence representing a promising live vaccine candidate against CVL.

Evaluation of thyroglobulin expression in murine reproductive organs during pregnancy.

PROBLEM: In pregnant women with antithyroglobulin antibody, prevalence of abortion is 2-4 fold higher compared to normal controls. Direct effect of such harmful autoantibodies on female reproductive organs may serve a role in pregnancy loss. METHOD OF STUDY: Expression of thyroglobulin in decidua, placenta, and ovary of pregnant Balb/c mice ((Balb/cxBalb/c and Balb/cxC57BL/6) during early, middle, and late stages of pregnancy was evaluated. Expression of thyroglobulin was investigated in these tissues by semi-quantitative RT-PCR. In addition, polyclonal antithyroglobulin antibody was produced, and expression of thyroglobulin protein in aforesaid tissues was evaluated by immunohistochemistry and dot-blot analysis. RESULTS: The results showed that thyroglobulin message is not expressed in placenta, decidua, or ovary in any stages of pregnancy. The same results were obtained at the protein level. CONCLUSION: It is likely that antithyroglobulin antibodies have no direct detrimental effect on such organs in patients with thyroid autoimmunity suffering from recurrent abortion.

Vitamin D3 receptor is expressed in the endometrium of cycling mice throughout the estrous cycle.

OBJECTIVE: To investigate the expression and localization of vitamin D(3) receptor (VDR) in reproductive organs of cycling mice. DESIGN: Experimental animal study. SETTING: Academic research center. ANIMAL(S): Mature (8 to 12 weeks old) cycling female Balb/c mice. INTERVENTION(S): Reproductive tissue, including endometrium, ovary, and fallopian tubes, were collected at each phase of estrous cycle to examine VDR expression. MAIN OUTCOME MEASURE(S): Expression of VDR messenger (mRNA) was determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). The presence and localization of VDR was assessed by immunohistochemistry, and the intensity of VDR expression was quantified with U.S. National Institutes of Health image-analysis software. RESULT(S): The VDR mRNA was expressed in the endometrium throughout the estrous cycle. The relative expression of VDR mRNA at the estrus phase was more prominent compared with the other phases. Immunohistochemical analysis revealed that dendritic cells, macrophages, and luminal and glandular epithelial cells of the endometrium, granulosa, and cumulus oophorus cells of the ovary and fallopian epithelial cells strongly express VDR, particularly during the estrus phase. CONCLUSION(S): Our findings have demonstrated, for the first time, that VDR is present and differentially expressed in murine reproductive organs throughout the estrous cycle. Further studies are required to evaluate the functional immunologic role of VDR.