Activation Of Mononuclear Cells Research Articles

Model to study (Na+, K+)-ATPase activation in human peripheral blood mononuclear cells and MCF-10A mammary cells by the PEG-Melatonin conjugate

Model to study (Na+, K+)-ATPase activation in human peripheral blood mononuclear cells and MCF-10A mammary cells by the PEG-Melatonin conjugate

Role of Nicotinamide in the Pathogenesis of Actinic Keratosis: Implications for NAD+/SIRT1 Pathway

Actinic keratosis (AK) is a precursor to invasive squamous cell carcinoma, making early diagnosis and treatment essential to prevent progression. Among available therapeutic options, nicotinamide (NAM) has shown potential in reducing AK progression. NAM is a precursor of nicotinamide adenine dinucleotide (NAD+), which activates sirtuin (SIRT)1, a protein with anti-cancer properties. Although the role of SIRT1 in AK is still debated, no data currently exist on the systemic modulation of this protein in AK. Therefore, this study aims to evaluate whether NAM, by increasing serum NAD+ levels, may promote SIRT1 activation in peripheral blood mononuclear cells (PBMCs) in AK patients. Thirty patients were enrolled and treated with NAM for 24 months. Hematological, biochemical, and skin condition assessments were conducted, alongside the measurement of SIRT1 and NAD+ levels. A decrease in basophils, monocytes, total cholesterol, and blood glucose levels was observed in the study group, along with a reduction in AK lesions. Notably, NAM treatment significantly enhanced serum NAD+ levels, and nuclear SIRT1 activity in PBMCs. In conclusion, NAM administration significantly reduced AK progression in a NAD+/SIRT1-dependent manner, supporting its role as a chemopreventive agent in AK management.

First-Line Combination of R-CHOP with the PDE4 Inhibitor Roflumilast for High-Risk DLBCL.

Diffuse large B-cell lymphoma (DLBCL) is a common and often fatal malignancy. The standard-of-care immunochemotherapy, R-CHOP, cures only about 60% of DLBCL patients. Improving this cure rate will likely require the effective translation of basic biology knowledge into clinical activities. We previously identified the cyclic-AMP/phosphodiesterase 4 (PDE4) axis as an important modulator of lymphomagenic processes. We also showed that the FDA-approved PDE4 inhibitor roflumilast can suppress B-cell receptor (BCR) signals, phosphoinositide 3-kinase (PI3K) activity and angiogenesis. These data suggested that combining roflumilast with R-CHOP may be beneficial in DLBCL. We conducted a single-center, single-arm, open-label, phase 1 study of roflumilast in combination with the standard of care, R-CHOP (Ro+R-CHOP), in pathologically proven, treatment-naïve, high-risk DLBCL patients. Ro+R-CHOP was safe, and at a median follow-up time of 44 months, 70% of patients were alive and disease free (median OS not reached, PFS 44% (95% CI, 21-92). In this pilot series, we found that the addition of roflumilast suppressed PI3K activity in peripheral blood mononuclear cells, and VEGF-A secretion in the urine. We also encountered preliminary evidence to suggest that the Ro+R-CHOP combination may be particularly beneficial to patients diagnosed with high-risk genetic subtypes of DLBCL, namely MCD and A53. These initial findings suggest that roflumilast may be an alternative agent able to inhibit BCR/PI3K activity and angiogenesis in DLBCL, and that the testing of Ro+R-CHOP in a larger series of genetically characterized tumors is warranted. This study was registered at ClinicalTrials.gov, number NCT03458546.

A Novel Dipterocarpol Derivative That Targets Alpha-Glucosidase and NLRP3 Inflammasome Activity for Treatment of Diabetes Mellitus.

Type 2 diabetes mellitus is a chronic metabolic disorder characterized by persistent hyperglycemia, chronic inflammation, impaired insulin secretion, and/or peripheral insulin resistance. Current α-glucosidase inhibitors approved for clinical use exhibit limited efficacy compared to other glucose-lowering agents. In this study, a series of mono- and bis-benzylidene derivatives were synthesized via aldol condensation of 3-oxo-dammarane triterpenoids with terephthalic aldehyde. The target mono- and bis-benzylidene derivatives, based on the dammarane triterpenoids hollongdione 1, (20S)-23,24-epoxy-25,26,27-trinordammar-3,24-dione 2, and 24(R,S)-20(S)-epoxy-25-hydroxy-dammar-3-one 3, were successfully synthesized. Several of these inhibitors demonstrated significantly greater efficacy than the reference drug acarbose. Notably, compound 4 inhibited S. cerevisiae α-glucosidase with an IC50 of 2.67 μM. Furthermore, the target compounds effectively inhibited NLRP3 inflammasome activation, reducing IL-1β production in LPS+ATP-stimulated murine peritoneal macrophages without detectable cytotoxicity. Compound 8, which exhibited dual activity, was further characterized as an inhibitor of NLRP3 activation in peripheral blood mononuclear cells, leading to the prevention of pyroptosis and IL-1β release. Additionally, compound 8 was shown to promote neuronal survival in LPS+ATP-treated rat hippocampal slices, highlighting its potential as a promising antidiabetic agent that targets both postprandial hyperglycemia and metaflammation.

An in-silico approach to the dynamics of proliferation potential in stem cells and the study of different therapies in cases of ovarian dysfunction

A discrete mathematical model based on ordinary differential equations and the associated continuous model formed by a partial differential equation, which simulate the generational and temporal evolution of a stem cell population, are proposed. The model parameters are the maximum proliferation potential and the rates of mitosis, death events and telomerase activity. The mean proliferation potential at each point in time is suggested as an indicator of population aging. The model is applied on hematopoietic stem cells (HSCs), with different telomerase activity rates, in a range of variation of maximum proliferation potential in healthy individuals, to study the temporal evolution of aging. HSCs express telomerase, however not at levels that are sufficient for maintaining constant telomere length with aging [1,2]. Women with primary ovarian insufficiency (POI) are known to have low telomerase activity in granulosa cells and peripheral blood mononuclear cells [3]. Extrapolating this to hematopoietic stem cells, the mathematical model shows the differences in proliferation potential of the cell populations when telomerase expression is activated using sexual steroids, though the endogenous promoter or with gene therapy using exogenous, stronger promoters within the adeno-associated virus. In the first case, proliferation potential of cells from POI condition increases, but when adeno-associated viruses are used, the proliferation potential reaches the levels of healthy cell populations.

Pentagalloylglucose alleviates acetaminophen-induced acute liver injury by modulating inflammation via cGAS-STING pathway

BackgroundThe cGAS-STING pathway is an important component of the innate immune system and plays significant role in acetaminophen-induced liver injury (AILI). Pentagalloylglucose (PGG) is a natural polyphenolic compound with various beneficial effects, including anti-cancer, antioxidant, anti-inflammatory, and liver-protective properties; however, whether it can be used for the treatment of AILI and the specific mechanism remain unclear.Materials and methodsA cell culture model was created to study the effect of PGG on cGAS-STING pathway activation using various techniques including western blotting (WB), real-time quantitative polymerase chain reaction (RT-qPCR), immunofluorescence (IF), and immunoprecipitation (IP). The effect of PGG was investigated in vivo by establishing a dimethylxanthenone acetic acid (DMXAA)-mediated activation model. An AILI model was used to evaluate the hepatoprotective and therapeutic effects of PGG by detecting liver function indicators, liver histopathology, and cGAS-STING pathway-related indicators in mice with AILI.ResultsPGG blocked cGAS-STING pathway activation in bone marrow-derived macrophages (BMDMs), THP-1 cells, and peripheral blood mononuclear cells (PBMCs) in vitro. Furthermore, PGG inhibited the generation of type I interferons (IFN-I) and the secretion of inflammatory factors in DMXAA-induced in vivo experiments. In addition, PGG also reduced serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP), improved liver tissue damage and apoptosis, and inhibited the cGAS-STING pathway activation caused by acetaminophen. In terms of the mechanism, PGG disrupted the connection between STING and TBK1.ConclusionsPGG exerts a protective effect against AILI by blocking the cGAS-STING pathway, offering a promising treatment strategy.

Increased expression of ER stress, inflammasome activation, and mitochondrial biogenesis-related genes in peripheral blood mononuclear cells in major depressive disorder.

A subset of major depressive disorder (MDD) is characterized by immune system dysfunction, but the intracellular origin of these immune changes remains unclear. Here we tested the hypothesis that abnormalities in endoplasmic reticulum (ER) stress, inflammasome activity and mitochondrial biogenesis contribute to the development of systemic inflammation in MDD. RT-qPCR was used to measure mRNA expression of key organellar genes from peripheral blood mononuclear cells (PBMCs) isolated from 186 MDD and 67 healthy control (HC) subjects. The comparative CT (2-ΔΔCT) method was applied to quantify mRNA expression using GAPDH as the reference gene. After controlling for age, sex, BMI, and medication status using linear regression models, expression of the inflammasome (NLRC4 and NLRP3) and the ER stress (XBP1u, XBP1s, and ATF4) genes was found to be significantly increased in the MDD versus the HC group. Sensitivity analyses excluding covariates yielded similar results. After excluding outliers, expression of the inflammasome genes was no longer statistically significant but expression of the ER stress genes (XBP1u, XBP1s, and ATF4) remained significant and the mitochondrial biogenesis gene, MFN2, was significantly increased in the MDD group. NLRC4 and MFN2 were positively correlated with serum C-reactive protein concentrations, while ASC trended significant. The altered expression of inflammasome activation, ER stress, and mitochondrial biogenesis pathway components suggest that dysfunction of these organelles may play a role in the pathogenesis of MDD.

Targeting toll-like receptor 7 as a therapeutic development strategy for systemic lupus erythematosus

Endosomal TLRs (TLR3/7/8/9) are highly analogous innate immunity sensors for various viral or bacterial RNA/DNA molecular patterns. Among them, TLR7, in particular, has been suggested to be a target for various inflammatory disorders and autoimmune diseases including systemic lupus erythematosus (SLE); but few small-molecule inhibitors with elaborated mechanism have been reported in literature. Here, we reported a well-characterized human TLR7-specific small-molecule inhibitor, TH-407b, with promising potency and negligible cytotoxicity through a novel binding mechanism. Notably, TH-407b not only effectively inhibited TLR7-mediated pro-inflammatory signaling in a variety of cultured cell lines but also demonstrated potent inflammation suppressing activities in primary peripheral blood mononuclear cells (PBMCs) derived from SLE patients. Furthermore, TH-407b showed prominent efficacy in vivo, improved survival rate and ameliorated symptoms of SLE model mice. To obtain molecular insights into the TH-407b derivatives’ inhibition mechanism, we performed the structural analysis of TLR7/TH-407b complex using cryogenic electron microscopy (cryo-EM) method. As an atomistic resolution cryo-EM structure of the TLR family, it not only of value to facilitate structure-based drug design, but also shed light to methodology development of small proteins using EM. Significantly, TH-407b has unveiled an inhibition strategy for TLR7 via stabilizing its resting/inactivated state. Such a resting state could be generally applicable to all TLRs, rendering a useful method for targeting this group of important immunological receptors.

Bighorn Sheep (Ovis canadensis) with Higher Whole Blood Selenium Levels Have Improved Survival and Altered Immune Responses.

Bighorn sheep (Ovis canadensis) are herbivorous ungulates that live in forage-poor areas of the American west. The trace minerals that herbivores derive from forage are important for immune function. Therefore, identifying trace minerals that affect immune function in bighorn sheep could provide important insights into disease susceptibility and population health in threatened populations. We sought to determine whether trace mineral composition in blood or plasma correlates to survival and determine whether immunologic parameters correlate with any trace minerals that affect survival. We used data collected from 2016 to 2018 as part of a large study on bighorn sheep in southeastern Oregon and northern Nevada, US. We measured the survival of 135 bighorn sheep during the 8-mo monitoring period, including general metrics of immune function and trace mineral levels. We found that animals with higher selenium had improved survival over the monitoring period, with higher peripheral blood mononuclear cell activity (lymphocytes and monocytes) and lower bacterial killing ability in an in vitro assay. This suggests that bighorn sheep may have altered immune function when selenium levels are low, making them more likely to die during the 8-mo monitoring period. Future work should consider whether habitat management strategies that increase selenium intake might improve disease resistance and survival in bighorn sheep in selenium-poor areas.

Acute exercise activates the AHR in peripheral blood mononuclear cells in an intensity-dependent manner.

The kynurenine pathway (KP) of tryptophan degradation generates several metabolites such as kynurenine (KYN) or kynurenic acid (KA) that serve as endogenous ligands of the aryl hydrocarbon receptor (AHR). Due to its distinct biological roles particularly modulating the immune system, the AHR is a current therapeutic target across different inflammation-related diseases. Here, we show an acute exercise-induced increase in AHR ligand availability on a systemic level and a kynurenine pathway activation in peripheral blood mononuclear cells (PBMCs). Concurrently, the AHR is activated in PBMCs following acute exercise. Exercise effects on both, kynurenic acid and AHR activation in PBMCs were greater in response to high-intensity interval exercise (HIIE) (50 min, six 3-min intervals at 90% V̇o2peak, and 3-min intervals at 50% V̇o2peak in between) compared with workload-matched moderate-intensity continuous exercise (MICE) (50 min). In conclusion, these data indicate a novel mechanistic link in how exercise modulates the immune system through the kynurenine pathway-AHR axis, potentially underlying exercise-induced benefits in various chronic diseases.NEW & NOTEWORTHY The findings of this study show that acute endurance exercise activates a receptor that has been described to integrate metabolic signals into the immune system. We uncover a potential mechanistic link on how exercise modulates the immune system through the kynurenine pathway-AHR axis, potentially underlying exercise-induced benefits in various chronic diseases and of relevance for other cell types.

Baseline DSB repair prediction of chronic rare Grade ≥ 3 toxicities induced by radiotherapy using classification algorithms.

Small fractions of patients suffer from radiotherapy late severe adverse events (AEs Grade ≥ 3), which are usually irreversible and badly affect their quality of life. A novel functional DNA repair assay characterizing several steps of double-strand break (DSB) repair mechanisms was used. DNA repair activities of peripheral blood mononuclear cells were monitored for 1 week using NEXT-SPOT assay in 177 breast and prostate cancer patients. Only seven patients had Grade ≥ 3 AEs, 6months after radiotherapy initiation. The machine learning method established the importance of variables among demographic, clinical and DNA repair data. The most relevant ones, all related to DNA repair, were employed to build a predictor. Predictors constructed with random forest and minimum bounding sphere predicted late Grade ≥ 3 AEs with a sensitivity of 100% and specificity of 77.17 and 86.22%, respectively. This multiplex functional approach strongly supports a dominant role for DSB repair in the development of chronic AEs. It also showed that affected patients share specific features related to functional aspects of DSB repair. This strategy may be suitable for routine clinical analysis and paves the way for modelling DSB repair associated with severe AEs induced by radiotherapy.

Immune profiling of age and adjuvant-specific activation of human blood mononuclear cells in vitro

Vaccination reduces morbidity and mortality due to infections, but efficacy may be limited due to distinct immunogenicity at the extremes of age. This raises the possibility of employing adjuvants to enhance immunogenicity and protection. Early IFNγ production is a hallmark of effective vaccine immunogenicity in adults serving as a biomarker that may predict effective adjuvanticity. We utilized mass cytometry (CyTOF) to dissect the source of adjuvant-induced cytokine production in human blood mononuclear cells (BMCs) from newborns (~39-week-gestation), adults (~18-63 years old) and elders (>65 years of age) after stimulation with pattern recognition receptors agonist (PRRa) adjuvants. Dimensionality reduction analysis of CyTOF data mapped the BMC compartment, elucidated age-specific immune responses and profiled PRR-mediated activation of monocytes and DCs upon adjuvant stimulation. Furthermore, we demonstrated PRRa adjuvants mediated innate IFNγ induction and mapped NK cells as the key source of TLR7/8 agonist (TLR7/8a) specific innate IFNγ responses. Hierarchical clustering analysis revealed age and TLR7/8a-specific accumulation of innate IFNγ producing γδ T cells. Our study demonstrates the application of mass cytometry and cutting-edge computational approaches to characterize immune responses across immunologically distinct age groups and may inform identification of the bespoke adjuvantation systems tailored to enhance immunity in distinct vulnerable populations.

Immunomodulation profile of the biosimilar trastuzumab MYL-1401O in a bioequivalence phase I study

The initial Phase-I single centre, single dose, randomized, double-blind, cross-over study was planned to assess the pharmacokinetic and pharmacodynamic bioequivalence of the trastuzumab biosimilar (MYL-1401O) compared to the reference Herceptin®. Their respective immunomodulation profile presented in this paper involved healthy males receiving a single infusion of both monoclonals, separated by a washout period. Sixty parameters were assessed in total, including serum cytokines, peripheral mononuclear cell (PBMC) subsets, cell activation and response to recall antigens and mitogen, pre- and post- infusion, as well as a cytokine release assay (CRA) at baseline. Trastuzumab infusion induced a transient and weak peak of serum IL-6 at 6 h, and a modulation of mononuclear cell subset profile and activation level, notably CD16 + cells. Except for CD8 + T cells, there were no significant differences between Herceptin® and MYL-1401O. In CRA, PBMC stimulated with MYL-1401O or Herceptin® similarly secreted IL-6, TNF-α, IL-1β, GM-CSF, IFN-γ, and IL-10, but no or low level of IL-2. Interestingly, some observed adverse events correlated with IL-2 and IFN-γ in CRA. MYL-1401O exhibited a very similar immunomodulation profile to Herceptin®, strongly supporting its bioequivalence. This approach may thus be included in a proof-of-concept study. CRA may be used as a predictive assay for the evaluation of clinical monoclonals.

Altered Histone Deacetylase Versus Histone Acetyltransferase Activity in Peripheral Blood Mononuclear Cells from Apparently Healthy Young Adults with Prior Exposure to Adverse Childhood Experiences

Introduction: Adverse childhood experiences (ACEs) are severe psychosocial stressors which occur in early developmental periods and promote later life cardiometabolic disease in a dose-dependent manner. ACE-related risk may be mediated in part by epigenetic alterations, particularly in myeloid lineage immune cells. Histone acetylation is a dynamic epigenetic process that regulates gene expression via modification of chromatin structure and is dictated by the opposed actions of histone acetyltransferases (HATs) and histone deacetylases (HDACs). An appropriate balance between HDAC and HAT activity is critical for maintaining cellular function, and an imbalance has been implicated in the premature development of human diseases including cardiometabolic disease. Glucocorticoids (e.g., cortisol) are well-described regulators of immune function and can influence histone acetylation through glucocorticoid receptors. Thus, we hypothesized that HDAC:HAT activity would be altered in young adults with prior ACE exposure, and that HDAC:HAT activity would be associated with salivary cortisol concentrations. Purpose: We examined HDAC:HAT activity in peripheral blood mononuclear cells (PBMCs) in apparently healthy young adults with versus without prior exposure to ACEs and explored whether circulating cortisol was associated with HDAC:HAT activity. Methods: PBMCs were isolated from whole blood collected within 1 hour of wakening from 27 young adult women who reported high (≥ 4 ACEs) ACE exposure (ACE4+; mean ± SD; age = 21 ± 3 y, BMI = 25.7 ± 4.5 kg/m2) and from 14 young adult women who reported no ACE exposure (CON; age = 21 ± 3 y, BMI = 26.1 ± 6 kg/m2). Salivary cortisol was also collected within 1 hour of wakening and 8 hours later. Nuclear proteins were isolated from PBMCs and HDAC and HAT activities were quantified by commercially available assay kits. Salivary cortisol was quantified via ELISA. Independent samples t-tests were used to examine differences in HDAC:HAT, HDAC, and HAT activity. Pearson correlation coeffcients were used to examine the relation of HDAC:HAT activity with morning and afternoon cortisol concentrations, and the diurnal cortisol slope in the complete sample. Results: HDAC:HAT activity was reduced in ACE4+ versus CON (140.4 ± 52 vs. 189.6 ± 42 arbitrary units, p = 0.004). This difference was primarily driven by reduced HDAC activity (13,706 ± 4,696 vs. 18,060 ± 3,641 ng/h/mg, p = 0.004) in ACE4+ versus CON, whereas HAT activity was not different (99.7 ± 11 vs. 96.1 ± 9 ng/h/mg, p = 0.30). HDAC:HAT activity was not associated with morning (r=0.27, p = 0.07) or afternoon (r=-0.23, p = 0.16) cortisol, but was associated with the diurnal cortisol slope (r=-0.37, p = 0.02). Discussion: Young adults with prior ACE exposure have an altered balance between HDAC and HAT activity in PBMCs that appears to be driven by lower HDAC activity, and which is negatively related to diurnal cortisol slope. These findings warrant further exploration, particularly regarding the specific HDACs implicated, their role in reduced cellular function as it relates to disease risk, and whether these can be modulated to improve function among those with ACE exposure. Further, our data support future examination of the role of glucocorticoid signaling in regulating histone acetylation in this population. This study was supported by the Center for Integrative Research on Childhood Adversity (Grant #P20GM109097), through the National Institute of General Medical Sciences (to NDMJ and TKT). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Immunomonitoring via ELISPOT Assay Reveals Attenuated T-Cell Immunity to CMV in Immunocompromised Liver-Transplant Patients.

Assessing immune responses to cytomegalovirus (CMV) after liver transplant in patients on immunosuppressive therapy remains challenging. In this study, employing ELISPOT assays, 52 liver-transplant recipients were evaluated for antiviral T-cell activity in peripheral blood mononuclear cells (PBMCs), measuring interferon-γ (IFN-γ) secretion upon stimulation with CMV-specific peptides (CMV peptide pool, CMV IE-1, and pp65 antigens). Parameters such as stimulation index, mean spot size, and mean spot count were measured. The study found that heightened immunosuppression, especially with prednisolone in triple therapy, significantly dampened CMV-specific immune responses. This was demonstrated by decreased IFN-γ production by CMV-specific T-cells (CMV peptide pool: p = 0.036; OR = 0.065 [95% CI: 0.005-0.840], pp65 antigen: p = 0.026; OR = 0.048 [95% CI: 0.003-0.699]). Increased immunosuppression correlated with reduced IFN-γ secretion per cell, reflected in smaller mean spot sizes for the CMV peptide pool (p = 0.019). Notably, shorter post-transplant intervals correlated with diminished antiviral T-cell IFN-γ release at two years (CMV peptide pool: p = 0.019; IE antigen: p = 0.010) and five years (CMV peptide pool: p = 0.0001; IE antigen: p = 0.002; pp65 antigen: p = 0.047), as did advancing age (pp65 antigen: p = 0.016, OR = 0.932, 95% CI: 0.881-0.987). Patients with undetectable CMV antigens had a notably higher risk of CMV reactivation within six months from blood collection, closely linked with triple immunosuppression and prednisolone use. These findings highlight the intricate interplay between immunosuppression, immune response dynamics, and CMV reactivation risk, emphasizing the necessity for tailored immunosuppressive strategies to mitigate CMV reactivation in liver-transplant recipients. It can be concluded that, particularly in the early months post-transplantation, the use of prednisolone as a third immunosuppressant should be critically reconsidered. Additionally, the use of prophylactic antiviral therapy effective against CMV in this context holds significant importance.

Comparative toxicological-hygienic assessment, structural-morphological, physicochemical characteristics, and virucidal properties of new nanopowder materials TiO2 and TiO2@Ag

In order to address safety concerns related to the acquisition and utilization of TiO2 and TiO2@Ag nanomaterials, as well as to investigate their disinfectant and biological effects, the structural-morphological, morpho­metry, toxicological, cytotoxic, and virucidal properties of these specified nanomaterials have been studied through experiments conducted on laboratory animals and in vitro. It has been demonstrated that the TiO2@Ag nanocomposite exhibited distinct physicochemical characteristics: it consisted of TiO2 nanoparticles ranging in size from 13 nm to 20 nm and Ag nanoparticles ranging from 35 nm to 40 nm with 4.0 wt% of silver localized on the surface of titanium dioxide. The purity of the modification of synthesized nano-TiO2 and nano-TiO2@Ag has been confirmed. Acute intraperitoneal administration of nanopowders revealed LD50 values of 4783.30 mg/kg for nano-TiO2 and 724.44 mg/kg for nano-TiO2@Ag. A slight accumulation was observed upon repeated (28-fold) intragastric administration of nano-TiO2. The cumulative dose administered, which equated to 15.9 multiples of the LD50 (76040 mg/kg), did not result in animal mortality but led to retardation in body weight gain. TiO2 and TiO2@Ag nanopowders do not irritate the skin, induce mild conjunctival irritation, and may exhibit a weak sensitizing effect. Nano-TiO2 and nano-TiO2@Ag powders accumulate in the tissues of internal organs and cause damage to the liver, kidneys, and lungs of laboratory animals upon intraperitoneal administration. The most characteristic morphological signs of the toxic effect of nano-TiO2 on liver tissue were observed at a level of 67.7% (cytoplasmic vacuolization in hepatocytes), while in the case of nano-TiO2@Ag initial necrotic changes were at a level of 70.0% (hepatocytes with pyknotic nuclei). Immunoassay analysis has demonstrated that TiO2@Ag and TiO2 nanomaterials at concentrations of 30 µg/ml can enhance the functional activity of peripheral blood mononuclear cells in vitro by increasing the production of cytokines IL-1, IL-6, TNF-α, and IL-4 in donors (p<0.05). This indicates the potential for chronic inflammation and allergic reactions among synthesis operators. In the study of the impact of nanomaterials on murine germ cells, it has been established that they affect the activity of mitochondrial enzymes and exert a damaging effect on mitochondrial membranes and overall cell integrity. Estimated approximate safe exposure levels in the workplace air are 0.3 mg/m3 for nano-TiO2 and 0.2 mg/m3 for nano-TiO2@Ag. Nano-TiO2@Ag and nano-TiO2 at a concentration of 100 µg/ml exhibit pronounced extracellular virucidal activity against human adenovirus serotype 2. The TiO2@Ag nanocomposite has a less damaging effect on Нер-2 cells compared to nano-TiO2.

HERV-E ƛ 4-1 activation in peripheral blood mononuclear cells of the recurrent depression patients under the influence of human recombinant IL-1β

IntroductionMental disorders represent complex phenotypes and are the leading causes of global disease burden. Human endogenous retroviruses (HERVs) are ancient retroviral DNA sequences established into germline. Their tight regulation is mainly achieved by epigenetic mechanisms, which can be altered by environmental factors - viral infections, inflammation, leading to HERV activation. The aberrant expression of HERVs associates with neurological diseases and mood disorders. We showed earlier that HERV-E ƛ 4-1 activation is associated with the recurrent depression stage of exacerbation and are accompanied by a pronounced increase in the proinflammatory activity of the peripheral blood mononuclear cells (PBMC).ObjectivesThe purpose of the study was to evaluate the activity of HERV-E ƛ 4-1 on PBMCs of patients with recurrent depression in remission, including under the influence of recombinant human IL-1β.MethodsThe study included 30 patients with an established diagnosis of recurrent depression (F 33.0) aged 26–45 years. PBMC were isolated using the Ficoll density gradient method and further cultured in the presence or absence of 1 mkg/ml of recombinant human IL-1β for 24 hours. HERV-E λ 4 – 1 env gene expression was determined by the PCR. Cells proliferative activity was determined by H3-thymidine incorporation. Cytokines content in culture supernatants was assessed by ELISA.ResultsIt was shown that in all samples of PBMC cultured without IL-1β the HERV-E λ 4 – 1 env expression was not determined. After the PBMC cocultivation with recombinant human IL-1β, HERV-E λ 4 – 1 env gene expression was determined in 86,7% of cases. The HERV-E ƛ 4-1 activation in PBMC after IL-1β influence was accompanied by increased cells proliferative activity and production of IL-1β, IL-6.ConclusionsOur data indicate that the HERV-E λ 4 – 1 env expression in PBMC of recurrent depression patients in the stage of remission induced by the influence of proinflammatory cytokines, such as IL-1β. This mechanism may be one of the possible regulators of HERV-E λ 4 – 1 activation in recurrent depression.Disclosure of InterestNone Declared

Comparison of lipopolysaccharide-mediated peripheral blood mononuclear cell activation between Brahman and Brahman × Thai native crossbreed cattle.

Lipopolysaccharide (LPS) is a robust endotoxin known to activate the immune system in cattle. The objective of this study was to investigate the effect of LPS on the morphology, cell viability, malondialdehyde (MDA), nitric oxide (NO), and total antioxidant capacity (TAC) of peripheral blood mononuclear cells (PBMCs) in Brahman and Brahman × Thai native crossbreed cattle. PBMCs were isolated from Brahman and Brahman × Thai native crossbreed cattle and treated with 0, 0.1, 1, and 10 μg/mL Escherichia coli LPS, respectively. Morphological changes in PBMCs were assessed at 24 and 48 h. In addition, we measured PBMC cell viability, MDA, NO, and TAC. LPS stimulation caused cell deformation and partial PBMC area enlargement, but there were no differences between Brahman and Brahman × Thai native crossbreed cattle. Stimulation at all levels did not affect the viability of PBMCs (p > 0.05). MDA and NO levels were significantly higher in Brahman cattle than in Brahman Thai native crossbred cattle (p < 0.05). TAC was significantly higher in Brahman × Thai native crossbred cattle than in Brahman cattle (p < 0.05). Immune cells of crossbreed cattle have a higher activation response to LPS than those of purebred cattle, and native crossbreed beef cattle have a higher antioxidant capacity than purebred beef cattle. This result may explain why hybrid cattle of indigenous breeds are more resistant to disease than purebred cattle.

Cytotoxicity and anti-inflammatory properties of a GLP-1 receptor agonist in a model of human peripheral blood mononuclear cell culture

&amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Introduction. &amp;lt;/strong&amp;gt;GLP-1R agonists (GLP-1RAs) are a type of anti-hyperglycemic medications used for the management of type 2 diabetes mellitus (T2DM). In addition to glucose-lowering effects, GLP-1R agonists (GLP-1RAs) also provide further advantages by promoting weight loss and controlling blood pressure. Furthermore, GLP-1RAs have been reported for their therapeutic benefits in neurological, cardiovascular, endocrine, and metabolic diseases. Emerging evidence from many clinical and experimental studies, as well as in vitro researches, suggests that GLP-1RA agonists may reduce inflamma tion and modify the immunological response, but the underlying molecu lar mechanisms remain unclear. In this research, we examined the effect of GLP-1RA on the cytotoxicity, proliferative activity, and cytokine production of human peripheral blood mononuclear cells (PBMCs) in vitro.&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt; Methods. &amp;lt;/strong&amp;gt;The peripheral blood mononuclear cells (PBMCs) cultures from healthy volunteers were used. GLP-1RA (DMB), in different concentrations, was added to the cell cultures. A flow cytometry assay was used to assess cell viability, while MTT and CFSE dye dilution assays were used to quantify proliferative activity. Cytokine levels were measured using a sandwich en zyme-linked immunosorbent assay (ELISA).&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Results.&amp;lt;/strong&amp;gt; The cytotoxicity data demonstrated that only the highest DMB concentration (1000 nM) decreased the metabolic activity (viability) of PBMCs (p&amp;amp;lt;0.05) in comparison to untreated cultures, while concentra tions of 200 nM (p&amp;amp;lt;0.05) and 1000 nM (p&amp;amp;lt;0.001) of GLP-1RA increased the proportion of late apoptotic and necrotic cells (p&amp;amp;lt;0.001). The prolif eration of PBMCs was significantly decreased in the presence of GLP-1RA at a 100 nM concentration when compared to the control (p&amp;amp;lt;0.05). The same concentration of GLP-1RA significantly reduced the production of IL-6, IL-1&amp;amp;beta;, and TNF-&amp;amp;alpha;.&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Conclusion.&amp;lt;/strong&amp;gt; Our results suggested that GLP-1RA (DMB), at a non-toxic concentration of 100 nM, inhibited the proliferation and production of pro-inflammatory cytokines by human PBMCs in vitro. These findings open the perspective to study the immune response in detail in future experiments.&amp;lt;/p&amp;gt;

5,6-dimethylxanthenone-4-acetic acid (DMXAA), a partial STING agonist, competes for human STING activation.

5,6-dimethylxanthenone-4-acetic acid (DMXAA) is a mouse-selective stimulator of interferon gene (STING) agonist exerting STING-dependent anti-tumor activity. Although DMXAA cannot fully activate human STING, DMXAA reached phase III in lung cancer clinical trials. How DMXAA is effective against human lung cancer is completely unknown. Here, we show that DMXAA is a partial STING agonist interfering with agonistic STING activation, which may explain its partial anti-tumor effect observed in humans, as STING was reported to be pro-tumorigenic for lung cancer cells with low antigenicity. Furthermore, we developed a DMXAA derivative-3-hydroxy-5-(4-hydroxybenzyl)-4-methyl-9H-xanthen-9-one (HHMX)-that can potently antagonize STING-mediated immune responses both in humans and mice. Notably, HHMX suppressed aberrant responses induced by STING gain-of-function mutations causing STING-associated vasculopathy with onset in infancy (SAVI) in in vitro experiments. Furthermore, HHMX treatment suppressed aberrant STING pathway activity in peripheral blood mononuclear cells from SAVI patients. Lastly, HHMX showed a potent therapeutic effect in SAVI mouse model by mitigating disease progression. Thus, HHMX offers therapeutic potential for STING-associated autoinflammatory diseases.