Long-Term Effects of Low-Dose Naltrexone on Immunomodulatory Properties of Human Adipose-Derived Mesenchymal Stem Cells.

Background: Low-dose naltrexone (LDN) is involved in the treatment of inflammatory and immune system diseases and can affect immune cells. Mesenchymal stem cells (MSCs) are known for their immunomodulatory effects and the potential for the treatment of certain types of autoimmune diseases. Objective: To investigate the long-term effects of LDN on human adipose-derived mesenchymal stem cells (ASCs) to see how their immunomodulatory properties are affected and also how LDN-treated ASCs interact with other immune cells present in peripheral blood mononuclear cells (PBMCs). Methods: After 14 days of treatment, the ability of LDN-treated ASCs to modulate PBMC proliferation in a two-way mixed lymphocyte reaction (MLR) model was assessed using XTT. The relative expression of IDO, PD-L1, COX-2, HGF genes, and the level of IL-6 and TGF-ß cytokines were measured in IFN-γ stimulated and unstimulated ASCs (treated and not treated cells) using real-time PCR and ELISA respectively. Results: Unstimulated ASCs treated with 10-8 M Naltrexone (10-8 M NTX) showed higher levels of TGF-ß, compared with the controls (P<0.05). Stimulated ASCs treated with 10-6 M NTX showed elevated expression of IDO, PD-L1 genes, and IL-6 level (P<0.05). Conclusion: Our results demonstrated that various LDN concentrations have dissimilar effects on ASCs' immunomodulatory properties. A higher LDN concentration induced an alteration in the immunomodulatory features of ASCs.

Alteration in IFN-γ and CCL2 serum levels at first trimester of pregnancy contribute to development of preeclampsia and fetal growth restriction.

OBJECTIVE: Pregnancy is a unique challenge for the immune system. Any disturbance in the immune system in the first trimester could result in further pregnancy complications. In this regard, the current study aimed to investigate the association between serum levels of a group of cytokines in the first trimester of pregnancy with the onset of preeclampsia (PE) and fetal growth restriction (FGR). MATERIALS AND METHODS: Serum samples were collected from 550 pregnant women at their 11th - 13th weeks of pregnancy and followed up to delivery. Out of all cases, 15 women complicated with preeclampsia and 15 ones diagnosed with FGR were included in the study. The serum levels of IFN-γ, CCL2, IL-10, IL-35 and IL-27 were checked in the collected sera of mentioned patients and compared to 60 women with normal pregnancy outcomes. RESULTS: In the preeclampsia group, the mean level of IFN-γ was significantly higher (p < 0.001) while the CCL2 serum level was significantly lower (p < 0.003) as compared to control group. There was no significant difference between the preeclampsia group and controls regarding other cytokines. In the FGR group, the mean serum level of IFN-γ was significantly higher compared to the healthy pregnancy group (p < 0.001) but other cytokines showed no significant differences. In the FGR group, a significant positive correlation was found between IL-10 level and neonates' weight (p < 0.05). CONCLUSION: Based on the results of the present study, an elevated level of IFN-γ and a reduced level of CCL2 at the first trimester of pregnancy could lead to complications such as PE and/or FGR.

In vitro-Generated MDSCs Reduce the Pregnancy Complications in an Abortion-Prone Murine Model.

Recurrent spontaneous abortion (RSA) is one of the major pregnancy-related complications. The roles of different immune cells have been studied in pregnancy complications. The current study aimed to investigate myeloid-derived suppressor cells (MDSCs) in a murine abortion model and introduce a therapeutic approach by using in vitro-generated MDSCs in this model. CBA/J × DBA/2 (abortion prone) and CBA/J × Balb/C (normal pregnancy) mice were used. The frequency of granulocytic MDSCs, monocytic MDSCs, and Tregs was checked in the bone marrow and uteroplacental tissue of mice on three gestational days (gd9.5, gd13.5, and gd17.5) using the flow cytometry approach. MDSCs were generated in vitro from bone marrow-isolated cells using GM-CSF and IL-6 cytokines. Abortion-prone mice were injected intravenously with in vitro-generated MDSCs at gd0.5, and pregnancy outcomes were recorded in treated mice. The frequency of G-MDSCs and M-MDSCs in the bone marrow of abortion-prone mice was decreased at gd9.5 (p = 0.026 and p = 0.05, respectively). In uteroplacental tissue, the frequency of G-MDSCs was significantly lower at gd9.5 and gd13.5 (p = 0.001, p = 0.029, respectively), while M-MDSCs only showed decreased number at gd9.5 (p = 0.05) in abortion-prone mice. Injection of in vitro-generated MDSCs resulted in the increased fetus and placenta weights (p = 0.049 and p = 0.012, respectively) but showed no effect on the number of live fetuses and abortion rate. The reduced frequency of both G-MDSCs and M-MDSCs in the bone marrow and at the feto-maternal interface is associated with pregnancy complications. In vitro-generated MDSCs could be considered as a potential approach to reduce these complications.

Are genetic variations in IL-1ß and IL-6 cytokines associated with the risk of pre-eclampsia? Evidence from a systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis study was performed to assess the potential association between interleukin-1 beta (IL-1ß) single nucleotide polymorphisms (SNPs) (rs1143634 and rs16944) and interleukin-6 (IL-6) SNP (rs1800795) and pre-eclampsia (PE). METHODS: A comprehensive literature search was conducted in the international search engines and databases, including MEDLINE (via PubMed), Scopus, and Web of Science (ISI) up to 9 March 2021. After retrieving relevant articles, data extraction was performed by four authors independently. Pooled ORs and corresponding 95% CIs were used to evaluate the association between IL-1ß and IL-6 polymorphisms and PE risk. Cochran's Q test was used to check heterogeneity, and the I2 index was calculated for measuring the heterogeneity between the estimations of included studies. RESULTS: After reviewing fully published studies, 21 studies were included in this study based on the eligibility criteria. Our results showed that rs16944 and rs1143634 of IL-1ß were significantly associated with the risk of PE. Regarding rs16944, the minor C allele significantly decreased the risk of PE (C vs. T: OR = 0.79, 95% CI = 0.69-0.90). In contrast, the minor T allele of rs1143634 significantly increased the risk of PE (T vs. C: OR = 1. 28, 95% CI = 1.04-1.58). There was no significant association between IL-6 rs1800795 (C vs. G: OR = 1.04, 95% CI = 0.93-1.16) polymorphism and PE risk. CONCLUSIONS: In conclusion, this meta-analysis suggests rs1143634 and rs16944 polymorphisms of IL-1ß are related to the risk of PE.

Evaluation of Transforming Growth Factor-ß1 and Interleukin-35 Serum Levels in Patients with Placenta Accreta.

OBJECTIVE: Placenta accreta is a pregnancy-related disorder with extreme trophoblast invasion and the adherence of the placenta to the uterine wall. This study aimed to investigate the serum level of transforming growth factor-beta 1 (TGF-ß1) and interleukin (IL)-35 in patients with placenta accreta. METHODS: Thirty-one women with placenta accreta and 57 healthy pregnant women were enrolled. The serum levels of TGF-ß1 and IL-35 were measured using the enzyme-linked immunosorbent assay method. RESULTS: The serum levels of both TGF-ß and IL-35 were significantly higher in the placenta accreta group compared with the group of healthy women (1082.48 pg/mL vs 497.33 pg/mL and 4541.14 pg/mL vs 1306.04 pg/mL; P <.001, respectively). Moreover, the level of TGF-ß1 positively correlated with the IL-35 level but other factors such as age, gestations, live births, and abortions did not correlate with IL-35 and TGF-ß1 levels. CONCLUSION: The serum levels of IL-35 and TGF-ß1 may contribute to the pathogenesis of placenta accreta and could be considered as potential targets in clinical and diagnostic approaches.

Analysis of the frequency of type 2 innate lymphoid cells and regulatory T cells in abortion-prone mice.

Recurrent spontaneous abortion (RSA) is the most common pregnancy related complication, affecting 1-5 % of pregnancies. Despite hormonal, genetic and anatomical factors that result in abortion, impairment of immune response at the feto-maternal interface during the first trimester of pregnancy is also one of the main causes of RSA. In the present study, we evaluated the frequency of blood and uterine group 2 innate lymphoid cells (ILC2s), their subsets and regulatory T cells (Tregs) in CBA/J × DBA/2 J as an abortion-prone model compared to normal pregnant (NP) mice using immunophenotyping. Results indicated that the percentages of ILC2s were significantly decreased in the AP group compared to the NP group at mid-gestation (P ≤ 0.01). Moreover, the percentages of both blood and uterine nILC2s were increased in NP mice at mid-gestation (P ≤ 0.01, and P ≤ 0.05, respectively), while iILC2s significantly increased in AP mice at mid-gestation (P ≤ 0.01, and P ≤ 0.05, respectively). Tregs were reduced in AP mice at both early and mid-gestation stages (P ≤ 0.01). Overall, our findings suggest that the changes in blood and uterine ILC2s might be associated with abortion in mice.

MDSCs in pregnancy: Critical players for a balanced immune system at the feto-maternal interface.

Myeloid-derived suppressor cells (MDSCs) have emerged as a new immune regulator at the feto-maternal interface. Although the phenotypes and functions of these cells were primarily studied in pathological conditions such as cancers and infections, new evidence has underscored their beneficial roles in homeostasis and physiological circumstances such as normal pregnancy. In this regard, studies have shown an increased number of MDSCs, particularly granulocytic MDSCs, at the feto-maternal interface. These cells participate in maintaining immunological tolerance between mother and semi-allograft fetus through various mechanisms. They further seem to play critical roles in placentation and fetus growth process. The absence or dysregulation of MDSCs during pregnancy have been reported in several pregnancy complications. These cells are also abundant in the cord blood of neonates so as to balance the immune responses and prevent aggressive inflammatory responses. The current review summarizes and organizes detailed data on MDSCs and their roles during pregnancy.

Evaluation of IL-17 and IL-35 Serum Levels in Patients with Preeclampsia.

BACKGROUND: Pre-eclampsia (PE) is the most common pregnancy complication affecting 2-8% of all pregnancies. PE could lead to maternal and prenatal morbidity. Imbalanced cytokine network and altered levels of several inflammatory and anti-inflammatory cytokines have been reported in PE. Because of scare information regarding the roles of IL-17 and IL-35 in PE, the current study aimed to investigate the serum level of these cytokines in a group of Iranian women suffering from PE. METHODS: Serum samples were collected from 100 pre-eclamptic and 100 healthy pregnant women. Patients and controls were matched for age, ethnicity and body mass index. The level of IL-35 and IL-17 were evaluated by ELISA technique. T test and one-way ANOVA with Tukey Post-Hoc test were used for analysis and p<0.05 were assumed significant. RESULTS: The serum level of IL-35 was increased in pre-eclamptic subjects as compared with healthy pregnant women (p<0.001). There was no significant difference in the serum level of IL-17 between pre-eclamptic and healthy pregnant women (p=0.73). Moreover, the results of the present study also showed that the pregnant women with severe pre-eclampsia had higher level of IL-35 in their sera when compared to those with mild form of the disease (p<0.001). In addition, the serum level of IL-35 was significantly elevated in women with higher proteinuria (p<0.001). CONCLUSION: Based on the our results, it seems that elevated levels of IL-35 in sera of pre-eclamptic women might work as a marker to evaluate the severity of the preeclampsia.

Immunization with HER2 extracellular subdomain proteins induces cellular response and tumor growth inhibition in mice.

AIM: We investigated cellular and protective immune responses in mice vaccinated with recombinant HER2 extracellular subdomains. MATERIALS & METHODS: Balb/C mice were immunized with recombinant full HER2 extracellular domain and subdomain proteins. Humoral and cellular immune response and antitumor effect was evaluated using a syngeneic mice tumor model. RESULTS: All recombinant proteins induced secretion of IL-4 and particularly IFN-γ and IL-17 cytokines. Challenging of immunized mice with stable 4T1-HER2 transfected cells resulted in partial but significant tumor growth inhibition in all groups of mice particularly those immunized with fHER2-ECD together with CPG. CONCLUSION: Our results suggest that the recombinant HER2-ECD subdomains induce mainly Th1 and Th17 responses, which seem to contribute to tumor growth inhibition in syngeneic mice.

Antibody Response to Human Extracellular HER2 Subdomain Proteins in Mice.

BACKGROUND: In addition to passive immunotherapy using anti-HER2 monoclonal antibodies, active immunotherapy via HER2 targeting is an interesting approach to inducing specific anti-tumor immune responses. We have recently reported the immunogenicity of HER2 subdomains following DNA immunization and HER2 protein boosting. In the present study, we evaluated the immunogenicity of different HER2 extracellular subdomains for the induction of anti-HER2 antibody response in BALB/c mice. OBJECTIVE: To investigate and characterize antibody responses to human recombinant proteins of HER2 extracellular subdomains in immunized mice. METHODS: Four subdomains of HER2 extracellular domain were expressed in E.coli; subsequently, purified recombinant proteins were intraperitoneally injected in BALB/c mice with Freund's adjuvant. The anti-HER2 antibody response was detected by ELISA, immunoblotting and flow cytometry. RESULTS: All the four HER2 subdomains along with the full extracellular domain (fECD) were able to induce specific anti-HER2 antibodies. Although anti-HER2 subdomains antibodies could not react with eukaryotic recombinant fECD protein by ELISA, they were able to recognize this protein by immunoblotting under both reduced and non-reduced conditions. Furthermore, only the sera of mice immunized with fECD protein could recognize native HER2 on HER2 overexpressing tumor cells (>99%) by flow cytometry. Moreover, fECD immunized mice sera inhibited the proliferation of tumor cells by XTT assay. CONCLUSION: The prokaryotic recombinant proteins of HER2 extracellular subdomains are immunogenic, yet the induced specific antibodies do not react with the native HER2 protein due to the paucity of post-translation modifications and /or distortion of the native conformation of isolated HER2 extracellular subdomains which might be potentially effective for induction of cell mediated immune response against HER2.

Autoimmunity in Primary Antibody Deficiencies.

Primary antibody deficiencies (PADs) are the most common inherited primary immunodeficiencies in humans, characterized by hypogammaglobulinemia, an inability to produce specific antibodies, and recurrent infections mainly caused by encapsulated bacteria. However, it has been shown that inflammatory disorders, granulomatous lesions, lymphoproliferative diseases, cancer, and autoimmunity are associated with the various types of PAD. Both systemic and organ-specific autoimmune diseases could be attributed to B-cell defects in PAD patients. Immune thrombocytopenic purpura and autoimmune hemolytic anemia are the most common autoimmune disorders in this group of patients. The aim of this review is to describe the proposed mechanisms for autoimmunity and to review the literature with respect to the reported autoimmune disorders in each type of PAD.