Peripheral Cells Research Articles

Differential decline of SARS-CoV-2-specific antibody levels, innate and adaptive immune cells, and shift of Th1/inflammatory to Th2 serum cytokine levels long after first COVID-19.

SARS-CoV-2 has triggered a pandemic and contributes to long-lasting morbidity. Several studies have investigated immediate cellular and humoral immune responses during acute infection. However, little is known about long-term effects of COVID-19 on the immune system. We performed a longitudinal investigation of cellular and humoral immune parameters in 106 non-vaccinated subjects ten weeks (10 w) and ten months (10 m) after their first SARS-CoV-2 infection. Peripheral blood immune cells were analyzed by multiparametric flow cytometry, serum cytokines were examined by multiplex technology. Antibodies specific for the Spike protein (S), the receptor-binding domain (RBD) and the nucleocapsid protein (NC) were determined. All parameters measured 10 w and 10 m after infection were compared with those of a matched, noninfected control group (n = 98). Whole blood flow cytometric analyses revealed that 10 m after COVID-19, convalescent patients compared to controls had reduced absolute granulocyte, monocyte, and lymphocyte counts, involving T, B, and NK cells, in particular CD3+CD45RA+CD62L+CD31+ recent thymic emigrant T cells and non-class-switched CD19+IgD+CD27+ memory B cells. Cellular changes were associated with a reversal from Th1- to Th2-dominated serum cytokine patterns. Strong declines of NC- and S-specific antibody levels were associated with younger age (by 10.3 years, p < .01) and fewer CD3-CD56+ NK and CD19+CD27+ B memory cells. Changes of T-cell subsets at 10 m such as normalization of effector and Treg numbers, decline of RTE, and increase of central memory T cell numbers were independent of antibody decline pattern. COVID-19 causes long-term reduction of innate and adaptive immune cells which is associated with a Th2 serum cytokine profile. This may provide an immunological mechanism for long-term sequelae after COVID-19.

LRRK2 kinase activity restricts NRF2-dependent mitochondrial protection in microglia.

Mounting evidence supports a critical role for central nervous system (CNS) glial cells in neuroinflammation and neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's Disease (PD), Multiple Sclerosis (MS), as well as neurovascular ischemic stroke. Previously, we found that loss of the PD-associated gene leucine-rich repeat kinase 2 (Lrrk2) in macrophages, peripheral innate immune cells, induced mitochondrial stress and elevated basal expression of type I interferon (IFN) stimulated genes (ISGs) due to chronic mitochondrial DNA engagement with the cGAS/STING DNA sensing pathway. Here, we report that loss of LRRK2 results in a paradoxical response in microglial cells, a CNS-specific macrophage population. In primary murine microglia and microglial cell lines, loss of Lrrk2 reduces tonic IFN signaling leading to a reduction in ISG expression. Consistent with reduced type I IFN, mitochondria from Lrrk2 KO microglia are protected from stress and have elevated metabolism. These protective phenotypes involve upregulation of NRF2, an important transcription factor in the response to oxidative stress and are restricted by LRRK2 kinase activity. Collectively, these findings illustrate a dichotomous role for LRRK2 within different immune cell populations and give insight into the fundamental differences between immune regulation in the CNS and the periphery.

Ultrastructure and Spectral Characteristics of the Compound Eye of Asiophrida xanthospilota (Baly, 1881) (Coleoptera, Chrysomelidae).

In this study, the morphology and ultrastructure of the compound eye of Asi. xanthospilota were examined by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), micro-computed tomography (μCT), and 3D reconstruction. Spectral sensitivity was investigated by electroretinogram (ERG) tests and phototropism experiments. The compound eye of Asi. xanthospilota is of the apposition type, consisting of 611.00 ± 17.53 ommatidia in males and 634.8 0 ± 24.73 ommatidia in females. Each ommatidium is composed of a subplano-convex cornea, an acone consisting of four cone cells, eight retinular cells along with the rhabdom, two primary pigment cells, and about 23 secondary pigment cells. The open type of rhabdom in Asi. xanthospilota consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells (R1~R6) and two distally attached rhabdomeric segments generated solely by R7, while R8 do not contribute to the rhabdom. The orientation of microvilli indicates that Asi. xanthospilota is unlikely to be a polarization-sensitive species. ERG testing showed that both males and females reacted to stimuli from red, yellow, green, blue, and ultraviolet light. Both males and females exhibited strong responses to blue and green light but weak responses to red light. The phototropism experiments showed that both males and females exhibited positive phototaxis to all five lights, with blue light significantly stronger than the others.

Priming lymphocyte responsiveness and differential T cell signaling in pediatric IBD patients with Cannabis use.

The prevalence of inflammatory bowel disease (IBD) has increased dramatically in recent years, particularly in pediatric populations. Successful remission with current therapies is limited and often transient, leading patients to seek alternative therapies for symptom relief, including the use of medical marijuana (Cannabis sativa). However, chronic cannabis use among IBD patients is associated with increased risk for surgical interventions. Therefore, determining the direct impact of cannabis use on immune modulation in IBD patients is of critical importance. Peripheral blood mononuclear cells of cannabis using and non-using pediatric IBD patients were phenotyped by flow cytometry and functionally assessed for their cytokine production profile. A phospho-kinase array was also performed to better understand changes in immune responses. Results were then compared with serum phytocannabinoid profiles of each patient to identify cannabinoid-correlated changes in immune responses. Results demonstrated elevated levels of a myriad of pro-inflammatory cytokines in users versus non-users. Differences in signaling cascades of activated T cells between users and non-users were also observed. A number of anti-inflammatory cytokines were inversely correlated with serum phytocannabinoids. These results suggest that cannabis exposure, which can desensitize cannabinoid receptors, may prime pro-inflammatory pathways in pediatric IBD patients.

Turner Syndrome: An Update Review

Turner syndrome was first described by Oklahoman physician Henri Turner in 1938. This syndrome can occur in females who have an absent X chromosome, either completely or partially. The two primary forms of TS are mosaic and classical. Data from newborn genetic screening and epidemiology in the US, Europe, and Japan suggest that it affects 1% to 3% of live female infants. Webbed neck, swollen hands and feet, shield-shaped chest, low hairline, droopy eyelids, high- arched palate, and elevated elbow carrying angle are among the physical traits associated with TS. Standard karyotyping, which looks at the chromosomes of 30 peripheral cells, can confirm the presence of Turner syndrome. Cardiovascular irregularity, hypogonadotropic hypogonadism, infertility, skeletal abnormalities, and autoimmune illnesses are among the complications associated with TS. The main treatment for TS is growth hormone therapy, with different approaches based on the organ involved.

Single-Cell RNA Sequencing Reveals Immunomodulatory Effects of Stem Cell Factor and Granulocyte Colony-Stimulating Factor Treatment in the Brains of Aged APP/PS1 Mice.

Alzheimer's disease (AD) leads to progressive neurodegeneration and dementia. AD primarily affects older adults with neuropathological changes including amyloid-beta (Aβ) deposition, neuroinflammation, and neurodegeneration. We have previously demonstrated that systemic treatment with combined stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) (SCF+G-CSF) reduces the Aβ load, increases Aβ uptake by activated microglia and macrophages, reduces neuroinflammation, and restores dendrites and synapses in the brains of aged APPswe/PS1dE9 (APP/PS1) mice. However, the mechanisms underlying SCF+G-CSF-enhanced brain repair in aged APP/PS1 mice remain unclear. This study used a transcriptomic approach to identify the potential mechanisms by which SCF+G-CSF treatment modulates microglia and peripheral myeloid cells to mitigate AD pathology in the aged brain. After injections of SCF+G-CSF for 5 consecutive days, single-cell RNA sequencing was performed on CD11b+ cells isolated from the brains of 28-month-old APP/PS1 mice. The vast majority of cell clusters aligned with transcriptional profiles of microglia in various activation states. However, SCF+G-CSF treatment dramatically increased a cell population showing upregulation of marker genes related to peripheral myeloid cells. Flow cytometry data also revealed an SCF+G-CSF-induced increase of cerebral CD45high/CD11b+ active phagocytes. SCF+G-CSF treatment robustly increased the transcription of genes implicated in immune cell activation, including gene sets that regulate inflammatory processes and cell migration. The expression of S100a8 and S100a9 was robustly enhanced following SCF+G-CSF treatment in all CD11b+ cell clusters. Moreover, the topmost genes differentially expressed with SCF+G-CSF treatment were largely upregulated in S100a8/9-positive cells, suggesting a well-conserved transcriptional profile related to SCF+G-CSF treatment in resident and peripherally derived CD11b+ immune cells. This S100a8/9-associated transcriptional profile contained notable genes related to pro-inflammatory and anti-inflammatory responses, neuroprotection, and Aβ plaque inhibition or clearance. Altogether, this study reveals the immunomodulatory effects of SCF+G-CSF treatment in the aged brain with AD pathology, which will guide future studies to further uncover the therapeutic mechanisms.

Glycogenolysis-Induced Astrocytic Serping1 Expression Regulates Neuroinflammatory Effects on Hippocampal neuron.

The bacterial pathogen, lipopolysaccharide (LPS), elicits microglial response and induces cytokine secretion that subsequently activates astrocytes. Recent findings have indicated that LPS-induced activation of postnatal glial cells has led to alterations in synapse formation in hippocampal and cortical neurons, thereby resulting in a prolonged increased risk for seizure or depression. Nevertheless, its mechanisms remain to be fully elucidated. Cellular metabolism has recently gained recognition as a critical regulatory mechanism for the activation of peripheral immune cells, as it supplies the requisite energy and metabolite for their activation. In the present study, we report that LPS did not change the expression of reported astrocyte-derived synaptogenic genes in the postnatal hippocampus; however, it induced upregulation of astrocytic complement component regulator Serping1 within the postnatal hippocampus. As a regulatory mechanism, activation of glycogen degradation (glycogenolysis) governs the expression of a subset of inflammatory-responsive genes including Serping1 through reactive oxygen species (ROS)-NF-κB axis. Our study further demonstrated that glycogenolysis is implicated in neurotoxic phenotypes of astrocytes, such as impaired neuronal synaptogenesis or cellular toxicity. These findings suggested that activation of glycogenolysis in postnatal astrocytes is an essential metabolic pathway for inducing responses in inflammatory astrocytes.

Predictive role of platelets to lymphocytes ratio and neutrophil to lymphocytes ratio in COPD exacerbation

BackgroundThe hallmark of COPD is the progressive destruction of the lung parenchyma, which is frequently brought on by the body's inflammatory reaction to external stimuli (such as smoking cigarettes or pollution). According to reports, the peripheral blood's essential immune-related cell populations' absolute counts and ratios can accurately represent chronic inflammatory diseases. Complex interactions between immune-related cells, such as lymphocytes and neutrophils, are involved in inflammation, which can cause irreversible damage and loss of respiratory tissue. The neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR), two hematological indicators of inflammation, have been studied in a variety of disease states, including solid tumors, systemic lupus erythematosus, coronary artery disease, retinal artery occlusion, chronic kidney disease, and stable COPD.AimCorrelation between NLR and PLR and outcome of COPD exacerbation.Materials and methodsThis cross-sectional study included 80 patients with COPD exacerbation who visited the outpatient clinic or were admitted to the Chest Department. CRP and calculation of NLR and PLR within 24 h from admission and 1 month after discharge were obtained to identify the prognostic value of NLR and PLR for the exacerbation, hospitalization, mechanical ventilation, and mortality in patients with COPD.ResultsDuring COPD exacerbation PLR, NLR showed a statistically significant correlation with the need for hospitalization with a p value < 0.001. As regards correlation with mortality NLR was statistically significant with a p value of 0.006 while PLR showed a non-significant p value of 0.077. PLR and NLR were correlated with CRP as an inflammatory marker and both were statistically significant with p value 0.004 and < 0.001 respectively. During exacerbation, PLR and NLR were correlated with the need for mechanical ventilation and the results were statistically significant with p value < 0.001. PLR and NLR showed a significant increase during exacerbation compared to stable COPD patients 1 month after discharge with p value of < 0.001.ConclusionPLR and NLR are simple tests that could be used to predict the severity of COPD exacerbation and the need for hospitalization, MV, and mortality prediction.

Expression of MMP2, MMP9, TIMP2 and TIMP3 genes in aortic dissection.

Thoracic aortic dissection (TAD) is a highly lethal disease occurring inside the aortic wall and is characterized by matrix degradation. Matrix metalloproteinases (MMPs) are members of a large endopeptidase family that function in the degradation of the extracellular matrix (ECM) proteins, the maintenance of the ECM, and the regulation of signaling in the aorta. MMPs are found in tissue with their natural inhibitors. Tissue inhibitors of metalloproteinases (TIMPs) are actively involved in both the activation and inhibition of MMPs. The present study was designed to determine the mRNA level gene expression differences of MMP2, MMP9, TIMP2 and TIMP3, which are considered to have an essential role in TAD, in aortic tissue and circulating monocyte cells. For the purpose of the present study, aortic vascular tissue and peripheral blood-derived monocyte cells were obtained from 10 patients with TAD and 10 control individuals. The gene expression levels of targeted genes (MMP2, MMP9, TIMP2 and TIMP3) were examined by droplet digital PCR. In research results, decreased expression of MMP9, TIMP2 and TIMP3 genes (P=0.043, P=0.009 and P=0.028, respectively) and increased ratio of MMP2/TIMP3 (P=0.012) were obtained in the aortic tissue. No changes were observed in terms of gene expression in monocyte cells. When the results obtained were evaluated within the framework of TAD pathogenesis, it was concluded that expression changes in MMP9, TIMP2 and TIMP3 genes may provide a sensitive environment in aortic tissue and may be associated with TAD formation. In addition, since the expression ratios of MMPs and TIMPs may reflect disease development, it was considered that the evaluation of MMPs along with TIMPs may be an appropriate and informative approach for future studies.

Orchestrating Stress Responses in Multiple Sclerosis: A Role for Astrocytic IFNγ Signaling.

Multiple sclerosis (MS) is an inflammatory and neurodegenerative disease that is characterized by the infiltration of peripheral immune cells into the central nervous system (CNS), secretion of inflammatory factors, demyelination, and axonal degeneration. Inflammatory mediators such as cytokines alter cellular function and activate resident CNS cells, including astrocytes. Notably, interferon (IFN)γ is a prominent pleiotropic cytokine involved in MS that contributes to disease pathogenesis. Astrocytes are dynamic cells that respond to changes in the cellular microenvironment and are highly responsive to many cytokines, including IFNγ. Throughout the course of MS, intrinsic cell stress is initiated in response to inflammation, which can impact the pathology. It is known that cell stress is pronounced during MS; however, the specific mechanisms relating IFNγ signaling to cell stress responses in astrocytes are still under investigation. This review will highlight the current literature regarding the impact of IFNγ signaling alone and in combination with other immune mediators on astrocyte synthesis of free oxygen radicals and cell death, and cover what is understood regarding astrocytic mitochondrial dysfunction and endoplasmic reticulum stress.

In-Vitro Proliferation and Enrichment of CD34+ Autologous Haematopoietic Stem Cells, Obtained from Patients with End-Stage Left Ventricular Failure

With a rising global prevalence of end-stage heart failure and a limited availability of cardiac transplantation programmes or left ventricular assist devices in many parts of the world, there is a renewed interest in potential alternative treatment options.Along with other groups, we have previously demonstrated the beneficial effect of intracoronary autologous bone marrow derived peripheral haemopoietic stem cell transplantation, to improve myocardial contractility in end-stage heart failure.We now assess the ability of these cells to expand in numbers in-vitro, to achieve enrichment of stem cell counts, using standard cell culture methods and flow- cytometric analysis.We demonstrate that with in-vitro culturing (within 3 passages post-harvest), the CD34+ stem cell fraction increases in standard culture media, across multiple samples. However, optimal culture conditions to achieve near pure stem cell populations with rapid cell proliferation, still needs to be defined.

Th17 pathway‐related immune signatures in the pathobiology of myasthenia gravis: Integrating the roles of regulatory/effector cytokines and transcription factors

AbstractObjectivesMyasthenia gravis (MG) is an autoimmune disorder mediated by antibodies against the acetylcholine receptor (AChR), muscle specific kinase (MuSK), and other antigens in the neuromuscular junction. Antibody production is influenced by T lymphocytes. The T helper 17 (Th17) subset, an inflammatory lineage of Th cells, is associated with several autoimmune diseases. Functional interactions between T lymphocytes and pathogenic antibody responses including aberrant Th17 cell responses have been reported in MG. However, the precise mechanism(s) underlying the activation and/or pathogenic transformation of Th17 cells are not clearly known. The current study aimed at simultaneously exploring the roles of the inducers, master regulator transcription factors, and effectors of Th17 cells in patients with MG.MethodsIn this cross‐sectional study, quantification of gene expression of IL6, IL17A, STAT3, and RORC in the peripheral mononuclear cells by quantitative polymerase chain reaction (qPCR) as well as estimation of plasma levels of IL‐1β, IL‐6, and IL‐17A cytokines by multiplex suspension assay were carried out in 59 patients with MG and 61 healthy controls.ResultsGene expression levels of IL17A were significantly upregulated in patients as compared to healthy controls. The plasma levels of IL‐1β, IL‐6, and IL‐17A were significantly elevated in patients compared to healthy controls. IL17A as well as RORC gene expressions correlated with the clinical features. IL17A gene expression levels were higher in AChR‐MG patients.ConclusionThe present study supports the crucial role of the Th17 pathway in the pathobiology of MG, including its potential influence on disease severity.

Inhibition of mast cell degranulation by novel small molecule MRGPRX2 antagonists

BackgroundMas-related G-protein coupled receptor X2 (MRGPRX2) is a promiscuous receptor on mast cells that mediates IgE-independent degranulation and has been implicated in multiple mast cell-mediated disorders, including chronic urticaria, atopic dermatitis, and pain disorders. Although it is a promising therapeutic target, few potent, selective, small molecule antagonists have been identified, and functional effects of human MRGPRX2 inhibition have not been evaluated in vivo. ObjectiveWe identified and characterized novel, potent, and selective orally active small molecule MRGPRX2 antagonists for potential treatment of mast cell-mediated disease. MethodsAntagonists were identified using multiple functional assays in cell lines overexpressing human MRGPRX2, LAD2 mast cells, human peripheral stem cell-derived mast cells, and isolated skin mast cells. Skin mast cell degranulation was evaluated in Mrgprb2em(-/-) knockout (KO) and Mrgprb2em(MRGPRX2) transgenic human MRGPRX2 knock-in (KI) mice by assessment of agonist-induced skin vascular permeability. Ex vivo skin mast cell degranulation and associated histamine release was evaluated by microdialysis of human skin tissue samples. ResultsMRGPRX2 antagonists potently inhibited agonist-induced MRGPRX2 activation and mast cell degranulation in all mast cell types tested, in an IgE-independent manner. Orally administered MRGPRX2 antagonists also inhibited agonist-induced degranulation and resulting vascular permeability in MRGPRX2 KI mice. In addition, antagonist treatment dose dependently inhibited agonist-induced degranulation in ex vivo human skin. ConclusionMRGPRX2 small molecule antagonists potently inhibited agonist-induced mast cell degranulation in vitro and in vivo as well as ex vivo in human skin, supporting potential therapeutic utility as a novel treatment for multiple human diseases involving clinically relevant mast cell activation.

The cytoplasmic tail of myelin protein zero induces morphological changes in lipid membranes

The major myelin protein expressed by the peripheral nervous system Schwann cells is protein zero (P0), which represents 50% of the total protein content in myelin. This 30-kDa integral membrane protein consists of an immunoglobulin (Ig)-like domain, a transmembrane helix, and a 69-residue C-terminal cytoplasmic tail (P0ct). The basic residues in P0ct contribute to the tight packing of myelin lipid bilayers, and alterations in the tail affect how P0 functions as an adhesion molecule necessary for the stability of compact myelin. Several neurodegenerative neuropathies are related to P0, including the more common Charcot-Marie-Tooth disease (CMT) and Dejerine-Sottas syndrome (DSS) as well as rare cases of motor and sensory polyneuropathy. We found that high P0ct concentrations affected the membrane properties of bicelles and induced a lamellar-to-inverted hexagonal phase transition, which caused bicelles to fuse into long, protein-containing filament-like structures. These structures likely reflect the formation of semicrystalline lipid domains with potential relevance for myelination. Not only is P0ct important for stacking lipid membranes, but time-lapse fluorescence microscopy also shows that it might affect membrane properties during myelination. We further describe recombinant production and low-resolution structural characterization of full-length human P0. Our findings shed light on P0ct effects on membrane properties, and with the successful purification of full-length P0, we have new tools to study the role of P0 in myelin formation and maintenance in vitro.

O-031 Tacrolimus treatment significantly improved IVF outcomes with euploid embryo transfer in women with repeated implantation failures (RIF) and elevated T helper (Th)1/Th2 cell ratios

Abstract Study question Dose tacrolimus improve implantation rate for RIF women showing elevated T helper (Th)1/Th2 cell ratios, particularly those undergoing IVF/ET with euploid blastocysts? Summary answer Tacrolimus improved the implantation rate in RIF women with elevated Th1/Th2 cell ratios undergoing IVF/ET using euploid blastocysts. What is known already The peripheral blood Th1 and Th2 cells determine immune inflammatory responses at the maternal-fetal interface. Previously, we reported that about 40% of women with RIF (≥4) had elevated Th1/Th2 cell ratios (≥10.3). The pregnancy rate was significantly improved when they were treated with tacrolimus, an immunosuppressive agent [AJRI 2015]. However, genetic embryonic concerns of RIF could not be ruled out since not all transferred embryos were genetically screened. Recently, we reported an adjusted cut-off value of the Th1/Th2 cell ratios (≥11.8) [AJRI 2021] for women with RIF based on the retrospective analysis. However, the prospective study has not been performed. Study design, size, duration A prospective cohort study was performed, including 569 infertile women with more than 4 times of RIF. The study participants received ET with euploid blastocysts from September 2020 to November 2021. All transferred blastocysts were confirmed as euploid or low-frequency mosaic by preimplantation genetic testing for aneuploidy, and the endometrial preparation for ET was made by using either hormone replacement cycle or natural ovulatory cycle. Participants/materials, setting, methods Before ET, all participants were measured for their peripheral blood Th1/Th2 (CD4+IFN-γ+/ CD4+IL-4+) cell ratios in the secretory phase. Women who had elevated Th1/Th2 cell ratios (≥10.3) received tacrolimus (2-4 mg daily). Tacrolimus was started 2 days before ET, and the hCG and gestational sac (GS) rates were calculated in women with or without tacrolimus. Main results and the role of chance Of 569 participants, 174 (30.6%) women showed elevated Th/Th2 cell ratios (≥10.3), whereas the remaining 395 women served as control (Control group). Among 174 women, 148 women received tacrolimus (Tac group), while 26 did not receive tacrolimus (no-Tac group). The hCG and GS rates of the Tac group were 73.0% and 64.2%, respectively, similar to the no-Tac group (69.2% and 57.7%, respectively, P=NS). Meanwhile the hCG and GS rates of the control group were 70.6% and 60.0%, respectively (P=NS). When the Th1/Th2 cell ratio cut-off value was set to ≥ 11.8, 123 women of the 569 participants (21.6%) had elevated Th1/Th2 cell ratios (≥11.8). Among them, 112 received tacrolimus (Tac2 group), and 11 did not tacrolimus (no-Tac2 group). The remaining 410 women were as a control group (Control2 group). The GS rate of the Tac2 group was 67.0%, which was significantly higher than that of the no-Tac group (36.3%, p &amp;lt; 0.05), while the GS rate of the Control2 group was 60.5% (P=NS, vs Control2 group). Tacrolimus dosing data was as follows; 11.8 or more but less than 15.8 of Th1/Th2 cell ratios were needed for 2 mg of tacrolimus daily, and 15.8 pr more was needed for 3 mg of tacrolimus. Limitations, reasons for caution The study was a controlled trial with a limited number of study population. Additionally, the endometrial changes or peripheral immune responses after tacrolimus were not evaluated thoroughly. Further study is needed for the tacrolimus effect on systematic immune responses and local endometrial immune milieu. Wider implications of the findings Before ET, screening for increased Th1/Th2 ratios (Cut-off value ≥11.8) may significantly improve IVF outcomes by selecting proper candidates for tacrolimus treatment and detecting the proper tacrolimus doses. Notably, a significant proportion of women with RIF have additional implantation failures, even with euploid embryos, when immune-inflammatory conditions were not controlled. Trial registration number not applicable

P-389 Miscarriage in recurrent pregnancy loss (RPL) patients is associated with decreased peripheral T follicular helper cells and double-positive T cells

Abstract Study question Is there a relation between certain T cell subpopulations in the peripheral blood and the reproductive outcome in patients with recurrent pregnancy loss (RPL)? Summary answer We found that miscarriage in RPL patients is associated with low quantities of peripheral T follicular helper cells (TFH) and double-positive T cells (DPT). What is known already Previous studies showed that, the quantity of certain types of immune cells, such as natural killer cells and B cells has been associated with recurrent miscarriages. It is also well known that the first trimester is characterized by inflammation profile, required for successful implantation and specific Th1/Th2-type immune microenvironment. Follicular T helper cells and rare T-cells populations such as double-positive and double-negative T cells also have an important effect on the post-implantation processes. However, the effect of these specific immune cell types and their relative quantities in relation to the reproduction outcome is not fully understood. Study design, size, duration This observational study was performed from November 2022 to September 2023. Blood samples were collected from 65 pregnant RPL women (≥2 gestational losses) aged 28-49 years during the first trimester, at 8-10 weeks of pregnancy. Patients were followed up and divided into two groups according to their reproductive outcome: live birth or miscarriage. The exclusion criteria were history of recent inflammatory, autoimmune or oncological diseases, recent antibiotic treatment, and endometrial pathologies. Participants/materials, setting, methods The percentage of eight peripheral T cell subpopulations were measured by flow cytometry: T helpers (CD3+CD4+CD8-), T killers (CD3+CD4-CD8+), double-positive T cells (DPT) (CD3+CD4+CD8+), double-negative T cells (CD3+CD4-CD8-), T follicular helper cells (TFH) (CD3+CD4+CD8-CD185+), T helper type 1 (TH1) (CD4+CD183+CD196-CD194-), type 2 (TH2) (CD4+CD183-CD194+CD196-), and type 17 (TH17) (CD4+CD183-CD194+CD196+) cells. Study groups were compared by Student’s t-test using SPSS v.21 (IBM Corp., Armonk, NY, USA). Main results and the role of chance Among the studied RPL patients, 41 women gave live birth and 24 patients had a miscarriage after the blood sample. The mean percentage and standard deviation in the of the studied T cell subpopulations was: T helpers (49.86%±14.07%), T killers (39.49%±11.50%), DPT (2.96%±1.12%), DNT (5.61%±4.76%), TFH (8.09%±3.03%), TH1 (20.86%±8.81%), TH2 (6.22%±3.68%), and TH17 (3.93%±2.37%).The performed Student’s t-test revealed significant difference only in the percentage of TFH and DPT cells between the two studied patient groups. The percentages of TFH cells and DPT cells were significantly lower in patient group with miscarriage compared to the patient group with live birth (8.07% vs. 13.35%, p = 0.04, and 1.07% vs. 2.44%, p = 0.02, respectively). Limitations, reasons for caution The study was limited in sample size. It would be beneficial future studies to include more subsets of T cells, such as TH9, TH22, and T reg. Wider implications of the findings Low percentage of peripheral TFH and DPT cells in RPL patients could be considered as an indication for potential risk of miscarriage. Routine measurement of these immune biomarkers from the peripheral blood might be beneficial for an adequate assessment and treatment of patients with previous pregnancy losses. Trial registration number not applicable

A unified metric of human immune health.

Immunological health has been challenging to characterize but could be defined as the absence of immune pathology. While shared features of some immune diseases and the concept of immunologic resilience based on age-independent adaptation to antigenic stimulation have been developed, general metrics of immune health and its utility for assessing clinically healthy individuals remain ill defined. Here we integrated transcriptomics, serum protein, peripheral immune cell frequency and clinical data from 228 patients with 22 monogenic conditions impacting key immunological pathways together with 42 age- and sex-matched healthy controls. Despite the high penetrance of monogenic lesions, differences between individuals in diverse immune parameters tended to dominate over those attributable to disease conditions or medication use. Unsupervised or supervised machine learning independently identified a score that distinguished healthy participants from patients with monogenic diseases, thus suggesting a quantitative immune health metric (IHM). In ten independent datasets, the IHM discriminated healthy from polygenic autoimmune and inflammatory disease states, marked aging in clinically healthy individuals, tracked disease activities and treatment responses in both immunological and nonimmunological diseases, and predicted age-dependent antibody responses to immunizations with different vaccines. This discriminatory power goes beyond that of the classical inflammatory biomarkers C-reactive protein and interleukin-6. Thus, deviations from health in diverse conditions, including aging, have shared systemic immune consequences, and we provide a web platform for calculating the IHM for other datasets, which could empower precision medicine.

Dose-Dependent Alterations of Lysosomal Activity and Alpha-Synuclein in Peripheral Blood Monocyte-Derived Macrophages and SH-SY5Y Neuroblastoma Cell Line by upon Inhibition of MTOR Protein Kinase – Assessment of the Prospects of Parkinson’s Disease Therapy

To date, the molecular mechanisms of the common neurodegenerative disorder Parkinson’s disease (PD) are unknown and, as a result, there is no neuroprotective therapy that may stop or slow down the process of neuronal cell death. The aim of the current study was to evaluate the prospects of using the mTOR molecule as a potential target for PD therapy due to the dose-dependent effect of mTOR kinase activity inhibition on cellular parameters associated with, PD pathogenesis. The study used peripheral blood monocyte-derived macrophages and SH-SY5Y neuroblastoma cell line. As a result, we have for the first time showed that inhibition of mTOR by Torin1 only at a concentration of 100 nM affects the level of the lysosomal enzyme glucocerebrosidase (GCase), encoded by the GBA1 gene. Mutations in GBA1 are considered a high-risk factor for PD development. This concentration led a decrease in pathological phosphorylated alpha-synuclein (Ser129), an increase in its stable tetrameric form with no changes in the lysosomal enzyme activities and concentrations of lysosphingolipids. Our findings suggest that inhibition of the mTOR protein kinase could be a promising approach for developing therapies for PD, particularly for GBA1-associated PD.

Telomerase activity, telomere length, and the euploidy rate of human embryos

Background Telomeres maintain chromosome stability, while telomerase counteracts their progressive shortening. Telomere length varies between cell types, with leukocyte telomere length (LTL) decreasing with age. Reduced telomerase activity has been linked to reproductive issues in females, such as low pregnancy rates and premature ovarian failure, with recent studies indicating correlations between telomere length in granulosa cells and IVF outcomes. Objectives The study aims to explore the relationship between telomere length, telomerase activity, and euploid blastocyst rate in infertile women undergoing IVF/ICSI PGT-A cycles. Methods This prospective study involves 108 patients undergoing controlled ovarian stimulation and PGT-A. Telomere length and telomerase activity were measured in peripheral mononuclear cells and granulosa cells (GC), respectively. Results The telomere repeat copy number to single gene copy number ratio (T/S) results respectively 0.6 ± 0.8 in leukocytes and 0.7 ± 0.9 in GC. An inverse relationship was found between LTL and the patient’s age (p < .01). A higher aneuploid rate was noticed in patients with short LTL, with no differences in ovarian reserve markers (p = .15), number of oocytes retrieved (p = .33), and number of MII (p = 0.42). No significant association was noticed between telomere length in GC and patients’ age (p = 0.95), in ovarian reserve markers (p = 0.32), number of oocytes retrieved (p = .58), number of MII (p = .74) and aneuploidy rate (p = .65). Conclusion LTL shows a significant inverse correlation with patient age and higher aneuploidy rates. Telomere length in GCs does not correlate with patient age or reproductive outcomes, indicating differential telomere dynamics between leukocytes and granulosa cells.

Causality of immune cells on primary sclerosing cholangitis: a bidirectional two-sample Mendelian randomization study.

Observational studies have indicated that immune dysregulation in primary sclerosing cholangitis (PSC) primarily involves intestinal-derived immune cells. However, the causal relationship between peripheral blood immune cells and PSC remains insufficiently understood. A bidirectional two-sample Mendelian randomization (MR) analysis was implemented to determine the causal effect between PBC and 731 immune cells. All datasets were extracted from a publicly available genetic database. The standard inverse variance weighted (IVW) method was selected as the main method for the causality analysis. Cochran's Q statistics and MR-Egger intercept were performed to evaluate heterogeneity and pleiotropy. In forward MR analysis, the expression ratios of CD11c on CD62L+ myeloid DC (OR = 1.136, 95% CI = 1.032-1.250, p = 0.009) and CD62L-myeloid DC AC (OR = 1.267, 95% CI = 1.086-1.477, p = 0.003) were correlated with a higher risk of PSC. Each one standard deviation increase of CD28 on resting regulatory T cells (Treg) (OR = 0.724, 95% CI = 0.630-0.833, p < 0.001) and CD3 on secreting Treg (OR = 0.893, 95% CI = 0.823-0.969, p = 0.007) negatively associated with the risk of PSC. In reverse MR analysis, PSC was identified with a genetic causal effect on EM CD8+ T cell AC, CD8+ T cell AC, CD28- CD127- CD25++ CD8+ T cell AC, CD28- CD25++ CD8+ T cell AC, CD28- CD8+ T cell/CD8+ T cell, CD28- CD8+ T cell AC, and CD45 RA- CD28- CD8+ T cell AC. Our study indicated the evidence of causal effects between PSC and immune cells, which may provide a potential foundation for future diagnosis and treatment of PSC.