Apoptotic Lymphocytes Research Articles

Evaluation of the effect of yellow laser (DPSS) light on human lymphocytes viability in vitro.

To evaluate the lymphocyte apoptotic impact of yellow laser light in vitro. The experimental study was conducted from November 2021 to April 2022 at the Postgraduate Medical Physics Laboratory, Mustansiriyah University, Baghdad, Iraq, and comprised blood samples from healthy volunteers. The samples were subjected to 1:1 dilution in isotonic phosphate buffered saline, and each sample was divided into two equal aliquots; one for irradiation, and other as control.The percentage of apoptotic lymphocyte was estimated before and after radiation exposure with low-level laser 589nm at 30J/cm², 50J/cm² and 70J/cm² energy intensities. Post-exposure evaluation was done immediately, and 1 and 2 hours after radiation on the viability of normal human cells. The vitality of the cells was determined using the trypan blue exclusion test. Data was analysed using SPSS 24. There were 26 healthy volunteers (16 male, 10 females) with an age range of (20-40) years. After the exposure, the percentage of lymphocytes that apoptose increased significantly when cells were irradiated at 70J/cm2 immediately compared to the controls (p≤ 0.05), but there was no significant differences with the 30J/cm² dose. After 1 and 2 hours, a significant reduction in the proportion of apoptotic lymphocytes was observed (p<0.05). Yellow low-level laser showed a noticeable protective effect on lymphocytes by decreasing the percentage of dead cells.

Enhanced autophagy and phagocytosis of apoptotic lymphocytes in splenic macrophages of acute ethanol-treated rats: Light and electron microscopic studies.

Autophagy is a prosurvival mechanism for the clearance of damaged cellular components, specifically upon exposure to various stressors. In lymphoid organs, excessive ethanol consumption increases lymphocyte apoptosis, resulting in immunosuppression. However, ethanol-induced autophagy and related phagocytosis of apoptotic lymphocytes in the spleen have not been studied yet. Adult male Wistar rats were injected intraperitoneally either with 5 g/kg ethanol or phosphate-buffered saline (as a control group) and then sacrificed 0, 3, 6, and 24 hours after injection. Light and transmission electron microscopy (TEM) findings indicated enhanced T cell apoptosis in the white pulps of ethanol-treated rats (ETRs) compared with the control group, which peaked at 6 h and was associated with the accumulation of tingible body macrophages (TBMs). These macrophages exhibited an upregulated autophagic response, as evidenced by enhanced LC3-II (a specific marker of autophagosomes) expression, which peaked at 24h. In addition, double labeling immunofluorescence of LC3-II with lysosomal markers revealed the enhanced formation of autolysosomes in TBMs of ETRs, which was associated with suppression of p62 immunostaining, indicating the enhanced autophagic flux. Interestingly, this elevated autophagic response in ETR TBMs was accompanied by evidence of LC3-associated phagocytosis (LAP) of apoptotic splenocytes. This is based on TUNEL/LC3-II double labeling and TEM observations of phagosomes containing apoptotic bodies, enclosed within phagosomal membranes adjacent to the autophagic vacuoles. It can be concluded that enhanced prosurvival autophagy in splenic TBMs of ETRs and clearing of apoptotic lymphocytes via LAP may contribute to preventing secondary necrosis and autoimmune diseases.

Modulation of Ionizing Radiation-Induced Apoptosis by Taurine in Human Peripheral Blood Lymphocytes: Flow Cytometry-based Quantification.

Radiotherapy, a highly effective method of radiation-based treating cancers, can reduce the size of tumors and affect healthy tissues. Radiation-induced lymphopenia as a side effect of radiation therapy can reduce the effectiveness of the treatment. This study aimed to examine how taurine can protect peripheral blood lymphocytes from radiation-based apoptosis. In this experimental study, the effects of the taurine on lymphocytes were studied, and blood samples were divided into three groups: a negative control group that was not treated, a positive control group that was treated with cysteine (100 μg/ml), and a group that was treated with taurine (100 µg. mL-1) in three different doses (4, 8 & 12 Gy) before irradiation. The percentage of apoptotic and necrotic lymphocytes was measured using flow cytometry 48 and 72 hours after the irradiation, respectively. According to the groups treated with taurine, the number of lymphocytes undergoing apoptosis was lower and higher compared to the negative and positive control groups, respectively. The decrease in this value was more pronounced 48 hours after radiation compared to 72 hours. Furthermore, there was a slight increase in the number of apoptotic lymphocytes with increasing radiation dose. Taurine effectively protects human peripheral blood lymphocytes from radiation-based apoptosis.

Hyperthermia-induced changes in leukocyte survival and phagocytosis: a comparative study in bovine and buffalo leukocytes.

Heat stress negatively affects health, welfare, and livestock productivity by impairing immune function, increasing disease incidence. In recent years, there has been increasing interest in understanding the immune system of water buffalo due to the growing economic impact of this species for the high quality and nutritional value of buffalo milk. While there are common responses across bovine and buffalo species, there are also some species-specific variations in the physiological responses to heat stress, mainly attributed to differences in metabolism and heat dissipation efficiency. At cellular level, the exposure to thermal stress induces several anomalies in cell functions. However, there is limited knowledge about the differential response of bovine and buffalo leucocytes to early and late exposure to different degrees of thermal exposure. The aim of this study was to compare the in vitro effect of hyperthermia on apoptosis and phagocytosis in leukocytes from bovine and buffalo species. For this, whole blood samples of six bovines and nine buffaloes were incubated at 39°C (mimicking normothermia condition) or 41°C (mimicking heat stress condition) for 1, 2, and 4 h. Two flow cytometric assays were then performed to evaluate apoptosis and determine functional capacity of phagocytic cells (neutrophils and monocytes). The results showed that the viability of bovine and buffalo leukocytes was differently affected by temperature and time of in vitro exposure. A higher percentage of apoptotic leukocytes was observed in bovines than in buffaloes at 39°C (3.19 vs. 1.51, p < 0.05) and 41°C (4.01 vs. 1.69, p < 0.05) and for all incubation time points (p < 0.05). In contrast, no difference was observed in the fraction of necrotic leukocytes between the two species. In both species, lymphocytes showed the highest sensitivity to hyperthermia, showing an increased apoptosis rates along with increased incubation time. In bovine, apoptotic lymphocytes increased from 5.79 to 12.7% at 39°C (p < 0.05), in buffalo, this population increased from 1.50 to 3.57% at 39°C and from 2.90 to 4.99% at 41°C (p < 0.05). Although no significant differences were found between the two species regarding the percentage of phagocytic neutrophils, lower phagocytosis capacity values (MFI, mean fluorescence intensity) were found in bovines compared with buffaloes at 41°C (27960.72 vs. 53676.45, p > 0.05). However, for monocytes, the differences between species were significant for both phagocytosis activity and capacity with lower percentages of bovine phagocytic monocytes after 2 h at 39°C and after 1 h at 41°C. The bovine monocytes showed lower MFI values for all temperature and time variations than buffaloes (37538.91 vs. 90445.47 at 39°C and 33752.91 vs. 70278.79 at 41°C, p < 0.05). In conclusion, the current study represents the first report on the comparative analysis of the effect of in vitro heat stress on bovine and buffalo leukocyte populations, highlighting that the leukocytes of buffalo exhibit relatively higher thermal adaptation than bovine cells.

Lymphocyte apoptosis and its association with the inflammatory markers and disease severity in juvenile-onset systemic lupus erythematosus patients

BackgroundThe defective clearance of apoptotic bodies in juvenile-onset systemic lupus erythematosus (jSLE) potentially leads to the persistence of autoreactive lymphocytes and the perpetuation of the autoimmune response. These factors contribute to the disturbance in lymphocyte apoptosis and show potential as key determinants in the clinical course and severity of jSLE. This study evaluates the role of peripheral blood (PB) lymphocyte apoptosis in prognosis of jSLE and as a predictor for disease activity.MethodsThe study involved 100 jSLE patients and 50 healthy controls. Flow cytometry was used to analyze percentages of lymphocyte apoptosis in PB of all study participants. Plasma levels of pro-inflammatory cytokines were determined using ELISA.ResultsOur results showed that percentages of lymphocyte apoptosis in PB of jSLE patients are significantly higher than those of healthy controls. These percentages are significantly positively associated with disease activity of patients (SLEDAI-2 K). Furthermore, plasma cytokine levels (IL-17, IFN-γ and TNF-α) are significantly elevated in jSLE patients compared to their levels in healthy controls. Also, there are weak significant positive correlations between percentages of PB lymphocyte apoptosis and each of IL-17 and IFN-γ plasma levels in jSLE patients. Moreover, PB lymphocyte apoptosis percentages among jSLE patients are higher in the presence of some clinical and laboratory features than those in their absence.ConclusionPeripheral apoptotic lymphocytes could contribute to the prognosis of jSLE and could be used as a predictor for disease activity in jSLE patients.

Apoptotic abnormal lymphocytes as a possible early indicator of clinical response in patients with ATL.

Apoptotic abnormal lymphocytes as a possible early indicator of clinical response in patients with ATL.

Prospective Analysis of B Lymphocyte Subtypes, before and after Initiation of Dialysis, in Patients with End-Stage Renal Disease.

CD5, CD27, BAFF, IgM and annexin were evaluated by flow cytometry on CD19+ cells in ESRD patients (n = 40), at time of initiating HD or CAPD (T0) and 6 months later (T6). A significant reduction in ESRD-T0 compared to controls was noticed for CD19+, 70.8 (46.5) vs. 171 (249), p < 0.0001, CD19+CD5-, 68.6 (43) vs. 168.9 (106), p < 0.0001, CD19+CD27-, 31.2 (22.1) vs. 59.7 (88.4), p < 0.0001, CD19+CD27+, 42.1 (63.6) vs. 84.3 (78.1), p = 0.002, CD19+BAFF+, 59.7 (37.8) vs. 127.9 (123.7), p < 0.0001 and CD19+IgM+ cells, 48.9 (42.8) vs. 112.5 (81.7) (K/μL), p < 0.0001. The ratio of early/late apoptotic B lymphocytes was reduced (16.8 (10.9) vs. 110 (25.4), p = 0.03). CD19+CD5+ cells were the only cell type with an increased proportion in ESRD-T0 patients (2.7 (3.7) vs. 0.6 (1.1), p < 0.0001). After 6 months on CAPD or HD, CD19+CD27-(%) and early apoptotic lymphocytes were reduced further. The HD patients also showed a significant increase in late apoptotic lymphocytes, from 1.2 (5.7) to 4.2 (7.2) K/mL, p = 0.02. B cells and most of their subtypes were significantly reduced in ESRD-T0 patients compared to controls, the only exception being CD19+CD5+ cells. Apoptotic changes were prominent in ESRD-T0 patients and were exacerbated by HD.

In vitro Assessment of Efferocytic Capacity of Human Macrophages Using Flow Cytometry.

Clearance of dying cells, named efferocytosis, is a pivotal function of professional phagocytes that impedes the accumulation of cell debris. Efferocytosis can be experimentally assessed by differentially tagging the target cells and professional phagocytes and analyzing by cell imaging or flow cytometry. Here, we describe an assay to evaluate the uptake of apoptotic cells (ACs) by human macrophages in vitro by labeling the different cells with commercially available dyes and analysis by flow cytometry. We detail the methods to prepare and label human macrophages and apoptotic lymphocytes and the in vitro approach to determine AC uptake. This protocol is based on previously published literature and allows for in vitro modeling of the efficiency of AC engulfment during continual efferocytosis process. Also, it can be modified to evaluate the clearance of different cell types by diverse professional phagocytes.

Koncentracija citokina (IL-4, IL-12 i IFNg) u plazmi i njena povezanost sa apoptozom limfocita pacijenata obolelih od hronične limfocitne leukemije

Introduction: Chronic lymphocytic leukemia (CLL) is a malignant disease of hematopoietic tissue and is the most common leukemia in adults. For years, the dominant view was that in the pathogenesis of chronic lymphocytic leukemia, the basic mechanism of the origin and progression of the disease is disruption in apoptosis and prolonged survival of malignant lymphocytes. Aim: The aim of our study is to determine the association between the percentage of apoptotic lymphocytes in the peripheral blood of patients suffering from chronic lymphocytic leukemia and the concentration of antiapoptotic cytokines (IL-4, IL-12, IFNg) in the patients' blood plasma. Materials and methods: The study included 29 patients suffering from chronic lymphocytic leukemia (21 men and 8 women) who had not been on a chemotherapy regimen in the preceding 6 months. Clinical parameters (clinical stage of disease, presence of lymphadenopathy, splenomegaly), biochemical parameters (LDH), and the type and percentage of bone marrow infiltration were determined in all patients. The percentage of apoptotic lymphocytes and the concentration of cytokines (IL-4, IL-12, IFNg) in the patients' plasma were determined from the patients' peripheral blood. Results: In the studied group of patients, plasma concentration values of IL-4 = 121.42 pg/ml (62.44 - 180.40), IL-12 = 7.62 pg/ml (4.36 - 10.87), IFNg = 31.45 pg/ml (18.35 - 44.56) were detected. In the cell population, less than 1% of apoptotic cells were detected, ranging from 0.03% to a maximum of 0.84%. The results show no correlation between the concentration of cytokines and the percentage of apoptotic lymphocytes in the patients' peripheral blood, however, they show that Il-12 concentration positively correlates with the stage of the disease, as well as with the percentage of bone marrow infiltration by malignant lymphocytes (p &lt; 0.001 or p = 0.028). Conclusion: Plasma concentrations of IL-4, IL-12, IFNg are not correlated with the percentage of apoptotic lymphocytes in the peripheral blood of patients with chronic lymphocytic leukemia. Interleukin-12 nevertheless shows a positive correlation in advanced disease.

Axl receptor induces efferocytosis, dampens M1 macrophage responses and promotes heart pathology in Trypanosoma cruzi infection

Adaptive immunity controls Trypanosoma cruzi infection, but the protozoan parasite persists and causes Chagas disease. T cells undergo apoptosis, and the efferocytosis of apoptotic cells might suppress macrophages and exacerbate parasite infection. Nonetheless, the receptors involved in the efferocytosis of apoptotic lymphocytes during infection remain unknow. Macrophages phagocytose apoptotic cells by using the TAM (Tyro3, Axl, Mer) family of receptors. To address how the efferocytosis of apoptotic cells affects macrophage-mediated immunity, we employ here Axl receptor- and Mer receptor-deficient mouse strains. In bone marrow-derived macrophages (BMDMs), both Axl and Mer receptors play a role in the efferocytosis of proapoptotic T cells from T. cruzi-infected mice. Moreover, treatment with a TAM receptor inhibitor blocks efferocytosis and upregulates M1 hallmarks induced by immune T cells from infected mice. Remarkably, the use of Axl−/− but not Mer−/− macrophages increases T-cell-induced M1 responses, such as nitric oxide production and control of parasite infection. Furthermore, infected Axl−/− mice show reduced peak parasitemia, defective efferocytosis, improved M1 responses, and ameliorated cardiac inflammation and fibrosis. Therefore, Axl induces efferocytosis, disrupts M1 responses, and promotes parasite infection and pathology in experimental Chagas disease. Axl stands as a potential host-direct target for switching macrophage phenotypes in infectious diseases.

The effects of medical linear accelerator X-rays on human peripheral blood lymphocytes in the presence of glucosamine.

Glucosamine is widely prescribed as a dietary supplement used to treat arthritis. In this study, the radioprotective ability of glucosamine was evaluated against radiation-induced genotoxicity and cytotoxicity in human peripheral blood lymphocytes. Blood samples were collected from five healthy male donors and were divided into four groups. Isolated lymphocytes and blood samples were treated with 10µM of glucosamine for 2h before exposure to 2Gy radiation. The radioprotective potential of glucosamine was assessed by micronucleus assay, reactive oxygen species (ROS) level analysis, and flow cytometry. Irradiation significantly increased the micronuclei frequency as compared to the control group. Contrary to that pretreatment with glucosamine before irradiation significantly reduced the frequency of micronuclei. Furthermore, pretreatment with glucosamine significantly prevented the percentage of apoptotic lymphocytes. Also, glucosamine pretreatment significantly reduced the production of ROS in irradiated lymphocytes. This study shows glucosamine to be a potent radioprotector against radiation that induces DNA damage and apoptosis in human lymphocytes. Several additional in vivo and in vitro studies are needed before glucosamine can be considered as a radioprotective candidate in patients undergoing radiation therapy.

Ameliorative Effects of Oyster Protein Hydrolysates on Cadmium-Induced Hepatic Injury in Mice.

Cadmium (Cd) is a widespread environmental toxicant that can cause severe hepatic injury. Oyster protein hydrolysates (OPs) have potential effects on preventing liver disease. In this study, thirty mice were randomly divided into five groups: the control, Cd, Cd + ethylenediaminetetraacetic acid (EDTA, 100 mg/kg), and low/high dose of OPs-treatment groups (100 mg/kg or 300 mg/kg). After continuous administration for 7 days, the ameliorative effect of OPs on Cd-induced acute hepatic injury in Cd-exposed mice was assessed. The results showed that OPs significantly improved the liver function profiles (serum ALT, AST, LDH, and ALP) in Cd-exposed mice. Histopathological analysis showed that OPs decreased apoptotic bodies, hemorrhage, lymphocyte accumulation, and inflammatory cell infiltration around central veins. OPs significantly retained the activities of SOD, CAT, and GSH-Px, and decreased the elevated hepatic MDA content in Cd-exposed mice. In addition, OPs exhibited a reductive effect on the inflammatory responses (IL-1β, IL-6, and TNF-α) and inhibitory effects on the expression of inflammation-related proteins (MIP-2 and COX-2) and the ERK/NF-κB signaling pathway. OPs suppressed the development of hepatocyte apoptosis (Bax, caspase-3, and Blc-2) and the activation of the PI3K/AKT signaling pathway in Cd-exposed mice. In conclusion, OPs ameliorated the Cd-induced hepatic injury by inhibiting oxidative damage and inflammatory responses, as well as the development of hepatocyte apoptosis via regulating the ERK/NF-κB and PI3K/AKT-related signaling pathways.

NEW EXPERIMENTAL APPROACH IN BIODOSIMETRY: EX VIVO APOPTOSIS DETECTION.

This study establishes a new experimental approach for retrospective biodosimetric assessment by apoptosis detection ex vivo. For this purpose, we used mononuclear blood leukocytes isolated from the peripheral blood of irradiated Wistar rats and cultured them ex vivo for posterior analysis. Using flow cytometry, we distinguished apoptotic lymphocyte subsets individual biodosimetric potential at different time periods after exposure: B-lymphocytes 6-8h (0-7Gy), natural killer cells 24h (0-7Gy) and T-lymphocytes 24h (0-1Gy). This novel experimental design innovates through the need of a single blood sample from irradiated individuals for a complete biodosimetric assessment.

Elaboration and pilot study of 3D vaccines for oncotherapy

The purpose of the study was to study the possibility of using intracorporeal constructs in vivo with healthy or autologous dead tumor cells on porous extracellular matrix of titanium nickelide (PEMTN).We aimed to determine the advantage of the effect of this method on the change in the immunological status of cancer patients in comparison with patients receiving traditional treatment.The study used CBA and AKR JY mice and studied 10 patients with solid stage IV tumors of various localization (pancreas, intestines, lungs, ovary, head and neck) and 3 oncohematological patients (lymphoblastic lymphosarcoma, chronic myeloid leukemia (CML)).PEMTN was seeded with a suspension with bone marrow cells from CBA mice and cultured for 8 weeks in a long-term Dexter culture. It was shown that after 6 weeks of incubation of bone marrow cells on PEMNT in vitro, the proportion of bone marrow cells produced from the pores of the matrix into the liquid medium varied within 58–82%, which corresponded to the figures of the 1st week of incubation.After implantation of PEMTN with fetal liver cells in AKR/JY mice with spontaneous lympholeukemia, the implant successfully engrafted and after 30 days, no noticeable fluctuations in the leukocyte count were observed. After 3–4 weeks implantation, a 3-fold increase in the level of erythrocytes with fetal hemoglobin, which is not normally found in adult AKR/JY mice, was observed. There was also an increase (by 274%, p &lt; 0.05) in the number of blood reticulocytes and a 26% decrease in the activity of the tumor process.In cancer patients with solid tumors, the level of SH-groups erythrocytes of blood increased 1.5–2.3 times 2 months after the implantation of hybrid oncotherapy implants carrying autologous apoptized tumor cells, treated in vitro. This implants, already 3–4 weeks after implantation in oncopatients, restored the blood system parameters.The most active (2–3 times) increased individual indicators of cellular immunity, in particular the number of NK cells, active (CD25+) and apoptotic lymphocytes (CD95+ marker). From the 3rd month of the study, the level of humoral immunity increased (immunoglobulins, circulating immune complexes). Clinically, the activation of immunity was accompanied by the stabilization of the process or a decrease in the volume and fragmentation of the primary nodes of solid tumors.In oncohematological patients, an increase in the CD95 marker in the peripheral cells of blood was observed.Therefore, in a patient with CML, the implantation, which followed therapy with low doses of cytostatics (myelosan, hydroxyurea) and the immune effect of the implantation, led to a 6-month hematological remission with normal values of the total number of leukocytes and leukocyte blood count. It has been shown that healthy cells in this matrix retain their viability and it allows them to multiply both in the in vitro system and in the in vivo system. The possibility of clinical use of PEMNT carrying autologous dead tumor cells treated in vitro with the aim of improving antitumor immunity, accelerating the recovery of blood counts in cancer patients and achieving partial remission has been shown.

MO876: B Lymphocyte Subpopulations in End-Stage Renal Disease Patients Undergoing Renal Replacement Therapy: Does the Method Affect the Phenotype?

Abstract BACKGROUND AND AIMS End-stage renal disease (ESRD) patients are considered as immunocompromised, and infections contribute greatly to their morbidity and mortality. This study focuses on the changes of B lymphocyte subpopulations in pre- and post- renal replacement therapy ESRD patients and the potential differences between haemodialysis and peritoneal dialysis. METHOD Using flow cytometry, B cells (CD19+) and their subsets B1a (CD19 + CD5+), naive (CD19 + CD27−), memory (CD19 + CD27+), (CD19 + BAFF-R+) and (CD19 + IgM+), were quantified in the peripheral blood of 40 pre-dialysis patients. IgG, IgA and IgM serum levels and apoptotic lymphocytes and b lymphocytes were also measured, and the measurements were repeated 6 months after the initiation of renal replacement therapy. The patients were allocated to haemodialysis (22patients, M/F 10/12, age 64,1 ± 9,8) and peritoneal dialysis (18 patients, M/F 11/11, age 56,4 ± 15,6). Exclusion criteria were age &amp;lt; 18 or &amp;gt;75 years, active autoimmune or chronic inflammatory disease, medical history of malignancy, corticosteroids or immunosuppresive treatment for the last 12 months. RESULTS There were no statistically significant difference between the two groups concerning the aforementioned variants pre dialysis. Collectively, ESRD patients showed no statistically significant alterations after the initiation of dialysis concerning the B cells phenotype, lymphocyte apoptosis and Immunoglobin serum levels, with the notable exception of B1a cells, which presented a decrease (3.6 ± 4.9 μ/L versus 1.6 ± 2.5 μ/L, P = 0.022). There seem to be no particular differences between the two methods either, with the exception of WBC count (6574 ± 1519 μ/L versus 8325 ± 2541 μ/L, P = 0.014) and apoptotic B lymphocytes (2 ± 2.4 μ/L versus 4.5 ± 3.9 μ/L, P = 0.02), which were lower in the peritoneal dialysis patients. Lastly there seemed to be no differentiation between the two methods concerning the percentage change of B lymphocytes subpopulations, lymphocyte apoptosis and IgG, IgM and IgA serum levels. CONCLUSION The changes that the uremic milieu causes in ESRD patients concerning their humoral Immunity do not reverse with the initiation of renal replacement therapy. Furthermore, with the exception of B cells apoptosis and WBC count, there is no significant difference between haemodialysis and peritoneal dialysis.

The Alleviating Effect of Herniarin Against Ionizing Radiation-Induced Genotoxicity and Cytotoxicity in Human Peripheral Blood Lymphocytes.

Herniarin is a simple coumarin that is found naturally in some plant species. In this study, we aimed to evaluate the protective effect of herniarin against ionizing radiation-induced genotoxicity and cytotoxicity in human peripheral blood lymphocytes. Herniarin was added to human lymphocytes before irradiation with a dose of 2 Gy of Xrays. The antagonistic potential of herniarin against radiation was measured by MTT [3-(4,5- dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide] assay, micronucleus assay, flow cytometry, and reactive oxygen species (ROS) level analysis. The maximum survival of lymphocytes against radiation was observed at a concentration of 50 μM of herniarin and a treatment time of 1 h. Pretreatment with 50 μM herniarin significantly decreased the micronuclei frequency, the percentage of apoptotic lymphocytes, and the ROS level in irradiated human lymphocytes. Moreover, 50 μM herniarin significantly increased the cytokinesis blocked proliferation index in irradiated lymphocytes. Herniarin could reduce radiation-induced cytotoxicity and genotoxicity in human lymphocytes. To complete the results of this study, it is suggested that in the future, more preclinical studies with larger samples or animal models be performed on herniarin.

Novel prognostic determinants of COVID-19-related mortality: A pilot study on severely-ill patients in Russia.

COVID-19 pandemic has posed a severe healthcare challenge calling for an integrated approach in determining the clues for early non-invasive diagnostics of the potentially severe cases and efficient patient stratification. Here we analyze the clinical, laboratory and CT scan characteristics associated with high risk of COVID-19-related death outcome in the cohort of severely-ill patients in Russia. The data obtained reveal that elevated dead lymphocyte counts, decreased early apoptotic lymphocytes, decreased CD14+/HLA-Dr+ monocytes, increased expression of JNK in PBMCs, elevated IL-17 and decreased PAI-1 serum levels are associated with a high risk of COVID-19-related mortality thus suggesting them to be new prognostic factors. This set of determinants could be used as early predictors of potentially severe course of COVID-19 for trials of prevention or timely treatment.

Effect of Streptococcus uberis on Gamma Delta T Cell Phenotype in Bovine Mammary Gland.

Simple SummaryBovine mastitis (inflammation of the mammary gland) is still an important problem for dairy farmers. This disease causes great financial losses across the world. The common method of treating mastitis is through the use of antibiotics. Antibiotic treatment should be minimized because of increasing antibiotic resistance. Streptococcus uberis (S. uberis) is one of the most important pathogens that causes bovine mastitis. This bacterium is able to hide and survive inside of epithelial cells. In this situation, antibiotic treatment is not efficient. Therefore, it is necessary to study the pathogenesis of mastitis that is caused by S. uberis to better understand how to treat this disease. In this study, we investigated a special type of lymphocytes—γδ T cells. The results of our study show that those cells may play a role in terminating inflammation in the mammary glands of cattle.In this study, we focused analyzing γδ T cells during bovine mammary gland inflammation induced by Streptococcus uberis. A mammary gland cell suspension was obtained using lavage 24, 48, 72, and 168 h after intramammary-induced infection. The proportion of lymphocytes increased during the entire week in which inflammation was present. The γδ T cells were also elevated during inflammation, reaching their peak at 72 h following induced inflammation. The percentage of apoptotic lymphocytes continually increased, with the highest proportion occurring 168 h after S. uberis infection. The results show that γδ T cells may be involved in the resolution of inflammation in bovine mammary glands, with the apoptosis of those cells potentially playing an important role.

Induction of Immune Tolerance in Islet Transplantation Using Apoptotic Donor Leukocytes.

Allogeneic islet transplantation has become an effective treatment option for severe Type 1 diabetes with intractable impaired awareness due to hypoglycemic events. Although current immunosuppressive protocols effectively prevent the acute rejection associated with initial T cell activation in recipients, chronic rejection has remained an obstacle for achieving long-term allogeneic islet engraftment. The development of donor-specific immune tolerance to the allograft is the ultimate goal given its potential ability to overcome chronic rejection and disregard the need for maintenance immunosuppression, which may be toxic to islet grafts. Recently, a breakthrough in tolerance induction during allogeneic islet transplantation using apoptotic donor lymphocytes (ADLs) in a non-human primate model had been reported. Several studies have suggested that the clonal depletion, anergy, and expansion of the antigen-specific regulatory immune network are the mechanisms for donor-specific tolerance with ADLs, which act synergistically to induce robust transplant tolerance. This achievement represents a huge step forward toward the clinical application of immune tolerance induction. We herein summarize the reported operational induction therapies in islet transplantation using the ADLs. Moreover, a few obstacles for the engraftment of transplanted islets, such as islet immunogenicity and instant blood-mediated response, which need to be resolved in the future, are also discussed.

ASSOCIATIONS BETWEEN BLOOD CONCENTRATIONS OF CYTOTOXIC CD8+ CELLS AND LYMPHOCYTE APOPTOSIS IN HEALTHY HUMANS

Introduction: Cytotoxic T-lymphocytes play an important role in a specific immune response via a lytic effect in relation to abnormal cells. The number of these cells greatly increases sin pathological states. In addition, an increased cytotoxic activity is a characteristic of the immune response of people living in the Far NorthTherefore, it is important to understand what function cytotoxic T-lymphocytes predominantly perform in healthy people in the North - cytolytic or suppressor? Aim: To assess associations between CD8+ concentration and immune response and apoptotic deaths of the lymphocytes in healthy individuals. Methods: Ninety-three healthy adult residents of the Russian North comprised the sample. Apoptotic lymphocyte death was studied by flow cytometry. FITC-annexine-V and propidium iodide labelled cells were detected. Concentrations of cytokines and apoptosis mediators were assessed by a solid-phase enzyme immunoassay. Neutrophiles, monocytes and phagocytic activity of neutrophils were studied in blood smears stained by Romanowsky's - Giemsa. The level of phenotypic activity of lymphocytes was assessed by double peroxidase labeling using monoclonal antibodies. The data were presented using means, standard deviations, medians, the 1st and the 3rd quartiles. All study participants were divided into two groups: with normal- (0.2-0,4 х109 kl/l) and elevated (more 0,6 х109 kl/l) blood cytotoxic lymphocyte levels. The groups were similar in terms of by age- and gender distribution. Continuous variables were analyzed using Mann-Whitney tests. Results: In individuals with an increased level of cytotoxic CD8+ lymphocytes in peripheral venous blood had greater concentrations of leukocytes (7.4 ± 0.49 х109 cells/l vs. 5.5 ± 0.23 х109, p = 0.003), lymphocytes (2.8 ± 0.17 х109 cells/l vs.1.8 ± 0.07 х109 cells/t p = 0.005), and mature neutrophils (4.1 ± 0.19 х109 cells/l vs. 3.4 ± 0.49 х109 cells/l, p = 0.013). No associations between the level of apoptosis of lymphocytes (AnV+/PI-) and concentrations of sFasL, TRAIL, TNFa, and cytochrome C were observed. Conclusions: Lymphocytes CD8+ in healthy residents of the Russian North perform mainly cytotoxic function, which is not related to apoptotic cellular death.