PD-1/PD-L1 Interaction Regulates BCL2, KI67, BAX, and CASP3, Altering Proliferation, Survival, and Apoptosis in Acute Myeloid Leukemia.

Programmed death ligand­1 (PD­L1) is a pivotal inhibitory checkpoint ligand known to induce T-cell exhaustion via interaction with the programmed death­1 (PD­1) receptor. Beyond this, PD-L1's intrinsic signaling pathways within cancer cells warrant further exploration. This study aims to elucidate the effect of PD-L1 stimulation on the proliferation, survival, and apoptosis of acute myeloid leukemia (AML) cell lines. Two human AML cell lines, HL-60 and THP-1 were cultured and treated with phorbol 12-myristate 13-acetate (PMA) to induce PD-L1overexpression. Post-treatment PD-L1 expression was confirmed via flow cytometry. Subsequently, cell surface PD-L1 was stimulated using a recombinant PD-1, 24 hours post-PMA treatment. The expression alterations in pivotal genes including BCL2, MKI67, BAX, and CASP3 were monitored using quantitative real-time polymerase chain reaction 24 and 48 hours post-treatment. Additionally, annexin-V through flow cytometry. Findings reveal that PD-L1 stimulation augments AML cell proliferation and survival by enhancing MKI67 and BCL2 expressions while concurrently inhibiting cell apoptosis due to decreased BAX and CASP3 expression following PD-L1 stimulation. Notably, stimulated cells expressed exhibited reduced annexin-V compared to control cells. This study underscores that PD-L1 stimulation fosters AML cell proliferation and survival while impeding cell apoptosis. The results hold potential implications for targeting PD-L1 in AML treatment strategies.

A Study of Autoantibodies against Some Central Nervous System Antigens and the IL-35 Serum Level in Schizophrenia.

Schizophrenia (SCZ) is a debilitating mental disorder with various causes involving complex interactions between genetic factors and environmental agents. The immune system plays a vital role in the pathology and function of the nervous system. Interleukin 35 (IL-35) is a regulatory and anti-inflammatory cytokine that can prevent autoimmune and inflammatory diseases. This study aimed to investigate the role of autoantibodies against some central nervous system (CNS) antigens and IL-35 serum levels in patients with Schizophrenia. This case-control study involved 80 participants. The serum levels of IL-35 were measured by enzyme-linked immunosorbent assay and the autoantibodies in the CNS by indirect immunofluorescence assay (IFA). The serum levels of IL-35 were decreased in patient groups compared to healthy subjects. Autoantibodies against N-methyl-D-aspartate receptor (NMDAR) and myelin-associated glycoprotein (MAG) were positive in 15% (6/40) and 7.5% (3/40), respectively; however, no antibodies against myelin, aquaporin-4 (AQP4), myelin oligodendrocyte glycoprotein (MOG), voltage-gated potassium channel (VGKC), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAR), γ-butyric acid receptor type B1 γ-butyric acid receptor type B1 (GABABR), antidipeptidyl peptidase-like protein-6 (DPPX), immunoglobulin-like cell adhesion molecule 5 (IgLON5), Glycine receptor (R) and acetylcholine receptor (Ach R) were detected (No statistics were computed).  We found that decreased serum IL-35 levels and the existence autoantibodies against NMDAR antigen may contribute to the pathogenesis of SCZ.

Autoantibodies against Central Nervous System Antigens and the Serum Levels of IL-32 in Patients with Schizophrenia.

BACKGROUND: Schizophrenia is a disease of the nervous system, and immune system disorders can affect its pathogenesis. Activation of microglia, proinflammatory cytokines, disruption of the blood-brain barrier due to inflammation, activation of autoreactive B cells, and consequently the production of autoantibodies against system antigens are among the immune processes involved in neurological diseases. Interleukin-32 (IL-32) is a proinflammatory cytokine that is essential in activating innate and adaptive immune responses. This study aimed to measure the serum level of IL-32 as well as the frequency of autoantibody positivity against several nervous system antigens in patients with schizophrenia. MATERIAL AND METHODS: This study was conducted on 40 patients with schizophrenia and 40 healthy individuals in the control group. Serum IL-32 levels were measured by ELISA. The frequency of autoantibodies against Hu, Ri, Yo, Tr, CV2, amphiphysin, SOX1, Zic4, ITPR1, CARP, glutamic acid decarboxylase GAD, recoverin, titin, and ganglioside antigens was measured by the indirect immunofluorescence method. RESULTS: Serum IL-32 levels in patients with schizophrenia were significantly higher compared to the control group. The frequency of autoantibodies against GAD and RI antigens in patients with schizophrenia was significantly higher than in the control group. Autoantibodies were positive in 8 patients for GAD antigen and 5 patients for RI antigen. Autoantibodies were also positive in 2 patients for CV2, 1 patient for Hu, and 1 patient for CARP. Negative results were reported for other antigens. CONCLUSION: Our findings suggest that elevated the serum IL-32 level and autoantibodies against GAD and RI antigens may be a reflection of immune system dysregulation in patients with schizophrenia.

Platelet spreading on fibrinogen matrix, a reliable and sensitive marker of platelet functional activity during storage.

Upon platelet activation, inside-out signals synergistically induced by a variety of agonists and adhesion molecules can enhance the affinity of platelet main integrin, αIIbß3 to its ligands. Integrin ligation with fibrinogen induces potent signals which develop platelet function including aggregation, release and spreading of which platelet spreading is considered as a major early consequence of αIIbß3 outside-in signaling. Study presented here evaluated platelet spreading on fibrinogen matrix as a marker of platelet activation during storage. PRP-platelet concentrates were subjected to flowcytometry analysis and the expression levels of P-selectin, CD61, GPIbα and active conformation of the αIIbß3 (PAC-1 binding) were examined on day 0, 1, 3 and 5 post-storage. Concurrently platelet adhesion and spreading on fibrinogen matrix, glucose concentration and LDH activity were also determined at the same intervals. Results showed significant decreases in platelet spreading on fibrinogen matrix during storage. Spreading was dominant pattern of adhesion till the first day of storage. In 3 day-stored platelets, filopodial or lamellipodial formation was dominant event whereas 5 day-stored platelets simply adhered to fibrinogen with less protrusion formation and partially failed to spread. Compared to simple adhesion, reduction of platelet spreading was also more significantly correlated with the usual markers of platelet storage lesion including P-selectin (r = - 0.88; p < 0.0001) and GPIbα expression (r = 0.76; p = 0.0001), PAC-1 binding (r = 0.66; p = 0.001), glucose concentration and LDH activity. Taken together, we introduced platelet spreading on fibrinogen matrix as a reliable and sensitive marker of platelets functional activity during storage. As a valid marker which is directly and obviously relevant to the platelet functional capacities, the rapid reduction of platelet spreading during storage overshadows other markers of platelet storage lesion while raising serious question about the quality of 5 day-stored platelets.

Correlation of interleukin 6 and transforming growth factor ß1 with peripheral blood regulatory T cells in rheumatoid arthritis patients: a potential biomarker.

INTRODUCTION: Proinflammatory cytokines and regulatory T cells (Tregs) are considered as important factors involved in autoimmunity development especially in rheumatoid arthritis (RA). AIM OF THE STUDY: To investigate the frequency of peripheral blood Tregs and related cytokines in RA patients and to determine the possible correlation between Treg percentage and interleukin 6 (IL-6) and transforming growth factor ß1 (TGF-ß1) as indicators in assessment of Treg function and mechanisms preceding autoimmunity in RA. MATERIAL AND METHODS: Thirty-seven Iranian RA patients with a moderate (3.2-5.1) disease activity score (DAS) and the same number of healthy age- and sex-matched individuals were enrolled. Frequency of peripheral blood Tregs (CD4+FoxP3+CD25high) was determined by flow cytometry. Serum levels of IL-6 and TGF-ß1 and their expression levels in peripheral blood mononuclear cells (PBMCs) were evaluated by ELISA and Q-PCR, respectively. RESULTS: Rheumatoid arthritis patients showed significantly lower peripheral blood Treg frequencies compared to healthy individuals. Additionally, Treg (%) showed a significant inverse correlation between serum concentrations of IL-6 and mRNA expression of PBMCs, whereas there was no significant correlation between Treg (%) and TGF-ß1 levels. CONCLUSIONS: The current study revealed that Treg numbers were reduced in peripheral blood of RA patients. This reduction inversely correlated with IL-6 levels, which may lead to persistent autoimmune and inflammatory conditions in RA patients.

Reverse correlations of collagen-dependent platelet aggregation and adhesion with GPVI shedding during storage.

Platelet receptor GPVI plays an important role in platelet firm adhesion to site of vascular injury. Receptor ligation with collagen, in company with other agonist/receptor interactions, augments inside out signaling pathways leading to platelet aggregation and thrombus formation. As GPVI expression is significantly modulated by ectodomain shedding, this study aimed to examine whether GPVI shedding functionally affects collagen-mediated platelet activation during storage. 6 PRP-platelet concentrates were subjected to adhesion analysis on collagen matrix under mild stirring condition as well as collagen-induced aggregation on day 1, 3 and 5 post-storage. Concurrently, platelet supernatants of same samples were fractionated by ultra-centrifugation and obtained micro-particle-free samples were subjected to western blot analysis for the evaluation of GPVI shedding. We showed a direct correlation between collagen-dependent platelet aggregation and adhesion (r = 0.8, p = 0.0001). The increasing levels of GPVI shedding during storage were in reverse correlation with collagen-induced platelet aggregation (r = - 0.82, p = 0.0004) which was significantly reducing during storage. Platelet adhesion to collagen matrix significantly decreased post-storage while it was also reversely correlated with the levels of GPVI shedding during 5 days storage of platelets (r = - 0.69, p = 0.002). Data presented here demonstrated that progressive shedding of surface adhesion receptor GPVI can affect its functional activities in stored platelets. Thereby considering the crucial role of GPVI in platelet adhesion to the site of injury, whether the therapeutic efficacy of banked platelet products could be influenced by storage-dependent shedding of this receptor, remains to be answered in future studies.

The Inhibitory Effect of Epigallocatechin Gallate on the Viability of T Lymphoblastic Leukemia Cells is Associated with Increase of Caspase-3 Level and Fas Expression.

Acute lymphoblastic leukemia is the most prevalent cancer in children. Novel components to help struggle aggressive malignancies and overcome some side effects of conventional treatments could be a promising strategy. Epigallocatechingallate (EGCG), have attracted the attention of scientists for prevention or treatment of some cancers. Jurkat cells were incubated with the different concentrations of EGCG (30-100 µm) for 24, 48, and 72 h and cell viability was investigated using MTS test. Apoptosis and the level of caspase 3 alterations were evaluated using flowcytometry and expression of Fas by Real Time PCR. EGCG decreased viability of cells with an inhibition concentration (IC50) of 82.8 ± 3.1, 68.8 ± 4 and 59.7 ± 4.8 µM in 24,48 and 72 h. 50, 70 and 100 µM concentrations of EGCG induced apoptosis in about 31, 40 and 71% of the cells, respectively. The mean value of caspase 3 positive cells in the presence of 50, 70 and 100 µm concentrations of EGCG was 19.3 ± 2.9, 29.5 ± 3.1 and 61.2 ± 3.4 respectively compared to 7.8 ± 1.1 in control with a significant difference at 100 µm concentration. Treatment with EGCG for 48 h enhanced the expression of Fas reaching to a significant level at 100 µM concentration. EGCG is effective in decrease cell viability, apoptosis induction and enhancement of caspase 3 and Fas expression level in jurkat cells. A comprehensive understanding of molecular events and pharmacokinetics of the component and experiments in animal models are required for dose determination and its interaction with other components of combination chemotherapy.

Superior integrin activating capacity and higher adhesion to fibrinogen matrix in buffy coat-derived platelet concentrates (PCs) compared to PRP-PCs.

BACKGROUND: Regardless of different sources, methods or devices which are applied for preparation of therapeutic platelets, these products are generally isolated from whole blood by the sedimentation techniques which are based on PRP or buffy coat (BC) separation. As a general fact, platelet preparation and storage are also associated with some deleterious changes that known as platelet storage lesion (PSL). Although these alternations in platelet functional activity are aggravated during storage, whether technical issues within preparation can affect integrin activation and platelet adhesion to fibrinogen were investigated in this study. METHODS: PRP- and BC-platelet concentrates (PCs) were subjected to flowcytometry analysis to examine the expression of platelet activation marker, P-selectin as well as active confirmation of the GPIIb/IIIa (αIIbß3) on day 0, 1, 3 and 5 post-storage. Platelet adhesion to fibrinogen matrix was evaluated by fluorescence microscopy. Glucose concentration and LDH activity were also measured by colorimetric methods. RESULTS: The increasing P-selectin expression during storage was in a reverse correlation with PAC-1 binding (r = -0.67; p = .001). PRP-PCs showed the higher level of P-selectin expression than BC-PCs, whereas the levels of PAC-1 binding and platelet adhesion to fibrinogen matrix were significantly lower in PRP-PCs. Higher levels of active confirmation of the GPIIb/IIIa in BC-PCs were also associated with greater concentration of glucose in these products. CONCLUSION: We demonstrated the superior capacities of integrin activation and adhesion to fibrinogen for BC-PCs compared to those of PRP-PCs. These findings may provide more advantages for BC method of platelet preparation.

Biological Effects of Hesperetin on Interleukin-6/Phosphorylated Signal Transducer and Activator of Transcription 3 Pathway Signaling in Prostate Cancer PC3 Cells.

BACKGROUND: Interleukin-6 (IL-6) is a multifunctional glycoprotein that regulates the growth of some tumors, including prostate carcinomas due to signal transducer and activator of transcription 3 (STAT3), extracellular signal-regulated kinases 1/2 (ERK1/2), and AKT signaling pathways. Hesperetin, as a flavanone, has several biological properties such as antitumor and anti-inflammatory. OBJECTIVE: This study was carried out to evaluate the biological effects of hesperetin on the IL-6 gene expression and phosphorylated STAT3, AKT, and ERK1/2 signaling pathways in PC3 prostate cancer (PC) cells. MATERIALS AND METHODS: In this study, we used real-time quantitative polymerase chain reaction (RT-qPCR) and ELISA to evaluate IL-6 gene expression and IL-6 protein secretion, respectively, in the treated PC3 cells with 0, 400, 450, and 500 µM of hesperetin. Cell survival studies were done by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay after 48 h treatment with hesperetin, and cell apoptosis was determined by flow cytometry. The protein levels of activated signaling molecules (pSTAT3, pAKT, and pERK1/2) analyzed by immunoprecipitation technique. RESULTS: Hesperetin-treated PC3 cells resulted in reduction of cell viability. Hesperetin led to the elevation of phosphorylated STAT3, ERK1/2, and AKT signaling proteins after 48 h in a dose-dependent manner as compared to the control cells. IL-6 gene expression, as well as protein level, significantly increased (P < 0.05) in a dose-dependent pattern in treated PC3 with hesperetin compared to the control cells. Further, hesperetin exposure resulted in the induction of cell cycle arrest at G0/G1 phase. CONCLUSION: Hesperetin in PC3 cells led to elevation IL-6 gene expression, IL-6 protein secretion, pSTAT3, pERK1/2 and pAKT intracellular signaling proteins. Our results indicate that hesperetin treatment leads to the inhibition of cell proliferation and the induction of cell cycle arrest at the G1 phase. Hesperetin can be considered a potent agent which synchronizes and stops cell cycle at G0/G1 phase to apply suitable chemotherapeutic agents and radiotherapy in PC cells. SUMMARY: This study evaluates biological effects of hesperetin on the cell cycle, interleukin-6 gene expression and some phosphorylated signaling pathways in PC3 prostate cancer cells. Hesperetin resulted in the inhibition of cell proliferation via inducing G0/G1 phase arrest in spite of the elevation of interleukin-6 gene expression and phosphorylated AKT, STAT3, and ERK1/2 intracellular signaling proteins. Therefore, hesperetin can be considered a potent agent which synchronizes and stop cell cycle at G0/G1 phase so that suitable chemotherapeutic agents can be applied in PC3 prostate cancer cells. Abbreviations Used: PC: Prostate cancer, IL-6: Interleukin-6, STAT3: Signal transducer activator of transcription 3, ERK1/2: Extracellular signal-regulated kinases 1/2, IC50: Inhibitory concentration of 50%.

Gallic Acid Inhibits Proliferation and Induces Apoptosis in Lymphoblastic Leukemia Cell Line (C121).

Leukemia is known as the world's fifth most prevalent cancer. New cytotoxic drugs have created considerable progress in the treatment, but side effects are still the important cause of mortality. Plant derivatives have been recently considered as important sources for the treatment of various diseases, including cancer. Gallic acid (GA) is a polyhydroxyphenolic compound with a wide range of biological functions. The aim of the present study was to evaluate the effect of GA on proliferation inhibition and apoptosis induction of a lymphoblastic leukemia cell line. Jurkat cell (C121) line was cultured in RPMI 1640 supplemented with 10% heat-inactivated fetal bovine serum (FBS) with different concentrations of GA (10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 µM) for 24, 48 and 72 hours. The effect of GA on cell viability was measured using MTS assay. Induction of apoptosis was evaluated with Annexin V-FITC/PI kit and flow cytometry. Data were analyzed by SPSS version 20 using Kruskal-Wallis and Dunn's multiple comparison tests. Decline of cell viability to less than 50% was observed at 60.3±1.6, 50.9±1.5, and 30.9±2.8 µM concentration after 24, 48, and 72 hours incubation, respectively. All concentrations of GA (10, 30, 50 and 80 µM) enhanced apoptosis compared to the control (P<0.05). The results demonstrate that the polyphenolic compound, GA, is effective in inhibition of proliferation and induction of apoptosis in Jurkat cell line. It is recommended to study the mechanism of apoptosis induction in future investigations.

Alteration of T Cell Subtypes in Beta-Thalassaemia Major: Impact of Ferritin Level.

INTRODUCTION: Oxidative damage and regular antigenic stimulation are main factors in accelerating immunosenescence. The present study was conducted to investigate new concepts of early immunosenescence in thalassaemia patients. MATERIALS AND METHODS: Twenty seven beta-thalassaemia major patients and a group of matched healthy volunteers aged 10-30 years in Shahrekord, Iran were recruited into the study. Ferritin level was determined and CD4 or CD8 T cells were analysed versus phenotyping markers, CD27, CD28, CD57 and CCR7, by flowcytometry. Data were analysed by Mann-Whitney and Spearman's correlation coefficient test in SPSS 11.5. RESULTS: Absolute lymphocytosis and partial decrease in T cells were observed in the patients. CD4+CD57+ and CD4+CCR7- T cells were significantly higher, whereas CD8+CD27+ and CD8+CCR7+ T cells were partially higher in patients. A negative correlation was observed between ferritin level and number of CD8+CD27+ and CD8+CCR7+ T cells, whereas the correlation was positive between ferritin level and number of CD57+ T cells. CONCLUSION: Moderate alteration of T cell repertoire and increase in CCR27-, CCR7-, and CD57+ T cells could reflect antigenic stimulation, decline in naïve T cells, and being closer to terminally differentiated cells. Effect of iron overload is potentially explained by positive correlation of blood transfusion and ferritin level with frequency of CD3+CD27- and that of ferritin with frequency of CD57+ T cells.