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We report the development of an optimized 50‐color spectral flow cytometry panel designed for the in‐depth analysis of the immune system in human blood and tissues, with the goal of maximizing the amount of information that can be collected using currently available flow cytometry platforms. We established and tested this panel using peripheral blood mononuclear cells (PBMCs), but included CD45 to enable its future use for the analysis of human tissue samples. The panel contains lineage markers for all major immune cell subsets, and an extensive set of phenotyping markers focused on the activation and differentiation status of the T cell and dendritic cell (DC) compartment. We outline the biological insight that can be gained from the simultaneous measurement of such a large number of proteins and propose that this approach provides a unique opportunity for the comprehensive exploration of the immune status in human samples with a limited number of cells. Of note, we tested the panel to be compatible with cell sorting for further downstream applications. Furthermore, to facilitate the wide‐spread implementation of such a panel across different cohorts and samples, we established a trimmed‐down 45‐color version which can be used with different spectral cytometry platforms. Finally, to generate this panel, we utilized not only existing panel design guidelines, but also developed new metrics to systematically identify the optimal combination of 50 fluorochromes and evaluate fluorochrome‐specific resolution in the context of a 50‐color unmixing matrix. [ABSTRACT FROM AUTHOR]

Intracellular lipid droplets (LDs) can accumulate in response to inflammation, metabolic stresses, and other physiological/pathological processes. Herein, we investigated whether spike proteins of SARS-CoV-2 induce LDs in human peripheral blood mononuclear cells (PBMCs) and in pulmonary microvascular endothelial cells (HPMECs). PBMCs or HPMECs were incubated alone or with endotoxin-free recombinant variants of trimeric spike glycoproteins (Alpha, Beta, Delta, and Omicron, 12 µg/mL). Afterward, cells were stained with Oil Red O for LDs, cytokine release was determined through ELISA, and the gene expression was analyzed through real-time PCR using TaqMan assays. Our data show that spikes induce LDs in PBMCs but not in HPMECs. In line with this, in PBMCs, spike proteins lower the expression of genes involving lipid metabolism and LD formation, such as SREBF1, HMGCS1, LDLR, and CD36. On the other hand, PBMCs exposed to spikes for 6 or 18 h did not increase in IL-1β, IL-6, IL-8, MCP-1, and TNFα release or expression as compared to non-treated controls. Thus, spike-induced LD formation in PBMCs seems to not be related to cell inflammatory activation. Further detailed studies are warranted to investigate in which specific immune cells spikes induce LDs, and what are the pathophysiological mechanisms and consequences of this induction in vivo. [ABSTRACT FROM AUTHOR]

Intracellular lipid droplets (LDs) can accumulate in response to inflammation, metabolic stresses, and other physiological/pathological processes. Herein, we investigated whether spike proteins of SARS-CoV-2 induce LDs in human peripheral blood mononuclear cells (PBMCs) and in pulmonary microvascular endothelial cells (HPMECs). PBMCs or HPMECs were incubated alone or with endotoxin-free recombinant variants of trimeric spike glycoproteins (Alpha, Beta, Delta, and Omicron, 12 µg/mL). Afterward, cells were stained with Oil Red O for LDs, cytokine release was determined through ELISA, and the gene expression was analyzed through real-time PCR using TaqMan assays. Our data show that spikes induce LDs in PBMCs but not in HPMECs. In line with this, in PBMCs, spike proteins lower the expression of genes involving lipid metabolism and LD formation, such as SREBF1, HMGCS1, LDLR, and CD36. On the other hand, PBMCs exposed to spikes for 6 or 18 h did not increase in IL-1β, IL-6, IL-8, MCP-1, and TNFα release or expression as compared to non-treated controls. Thus, spike-induced LD formation in PBMCs seems to not be related to cell inflammatory activation. Further detailed studies are warranted to investigate in which specific immune cells spikes induce LDs, and what are the pathophysiological mechanisms and consequences of this induction in vivo.

Using full spectrum flow cytometry, we designed a 28‐color panel for the analysis of markers known to be associated with the γδ T cell immune response. This panel allows the classification of γδ T cell subsets via specific V gene usage (Vγ9, Vδ1, Vδ2, and Vδ3) of their T cell receptor (TCR) and according to their functional differentiation. Phenotypical surface receptors to distinguish different stages of cell maturation included CD45RA, CD27, CD28, CD127, CD57, and CD16; chemokine receptors CXCR6, CCR5, CCR6, and CX3CR1; NK‐associated markers NKG2A, NKG2D, CD56, and CD161, checkpoint‐inhibitor PD‐1, and activating receptors CD38 and CD25. T cell lineage markers for the analysis of αβ T cells (CD4 and CD8) and MAIT cells (Vα7.2) were also included. This optimized multicolor panel allows a comprehensive immune‐profiling of all main human γδ T cell subsets and is suitable for longitudinal or exploratory analysis of γδ T cell development and γδ T cell dynamics in clinical cohorts. [ABSTRACT FROM AUTHOR]

Summary: Myeloid lineage cells use TLRs to recognize and respond to diverse microbial ligands. Although unique transcription factors dictate the outcome of specific TLR signaling, whether lineage-specific differences exist to further modulate the quality of TLR-induced inflammation remains unclear. Comprehensive analysis of global gene transcription in human monocytes, monocyte-derived macrophages, and monocyte-derived dendritic cells stimulated with various TLR ligands identifies multiple lineage-specific, TLR-responsive gene programs. Monocytes are hyperresponsive to TLR7/8 stimulation that correlates with the higher expression of the receptors. While macrophages and monocytes express similar levels of TLR4, macrophages, but not monocytes, upregulate interferon-stimulated genes (ISGs) in response to TLR4 stimulation. We find that TLR4 signaling in macrophages uniquely engages transcription factor IRF1, which facilitates the opening of ISG loci for transcription. This study provides a critical mechanistic basis for lineage-specific TLR responses and uncovers IRF1 as a master regulator for the ISG transcriptional program in human macrophages.

Purpose and appropriate samples: This 27‐color panel has been validated and optimized to comprehensively profile natural killer (NK) cells isolated from human tumors using a collagenase Type II‐based digestion protocol. We confirmed that detection of protein expression by antibodies used in our final panel was not affected during tissue digestion. During this evaluation process, we found that detection of CD56, a biomarker typically used to identify NK cells, was affected substantially by collagenase‐based digestion. Thus, our panel is centered around expression of NKp46, which is sufficient to identify NK cells and not affected by the tissue collagenase digestion step. Our panel further includes biomarkers used to extrapolate NK‐cell maturation, differentiation, migration, homing potential, and functional state. Our panel is intended to provide in‐depth characterization of human NK cells isolated from tissues, which we specifically tested using oral squamous cell carcinomas tissues, but it is compatible with other tissues that can be dissociated with a collagenase Type II‐based protocol. © 2020 The Authors. Cytometry Part A published by Wiley Periodicals LLC on behalf of International Society for Advancement of Cytometry. [ABSTRACT FROM AUTHOR]

Purpose: The effect of Actovegin® was investigated on PMA- and LPS-induced human peripheral blood mononuclear cells (PBMCs).Methods: PBMCs (1 × 106 cells/ml) from five blood donors (2 f, 3 m; 45-55 years) were grown in medium and exposed to Actovegin® in the presence or absence of PMA or LPS. Supernatants were collected to assess the concentration of cytokines (TNF-α, IL-1beta, IL-6 and IL-10). The reactive oxygen species (ROS) were assessed by a ROS-GloTM H2O2 assay.Results: Stimulation of cells by PMA or LPS (without Actovegin®) significantly increased the secretion of IL-1beta, IL-6, IL-10 and TNF-α from PBMCs, compared to controls. Pre-treatment of cells with Actovegin® (1, 5, 25, 125 µg/ml) plus PMA significantly decreased the secretion of IL-1beta from PBMCs, compared to controls (PMA without Actovegin®). In contrast, addition of Actovegin® (1, 5, 25, 125 and 250 µg/ml) plus LPS did not alter the IL-1beta production, compared to controls (LPS without Actovegin®). TNF-α, IL-6 and IL-10 do not contribute to the reduction of inflammatory reactions with Actovegin®.Conclusions: Actovegin® can reduce the PMA-induced IL-1beta release and the ROS production from PBMCs. These findings may help to explain the clinically known positive effects of Actovegin® on athletic injuries with inflammatory responses (e.g., muscle injuries, tendinopathies). [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles (NPs) by green route approaches has advantages over conventional methods. In green synthesis, we use eco-friendly plant extracts contain secondary metabolites and bioactive components, proteins that act as both reducing and capping agents, form stable and shape-controlled green silver nanoparticles. The current study deals with the synthesis of silver nanoparticles using the aqueous latex extract of Allmanda cathartica. The green silver nanoparticles are characterized by using different spectroscopic methods like ultra violet-visible spectroscopy (UV-Vis), Fourier transform-infrared spectroscopy (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD). Results indicated that the crystalline natured particles were spherical shaped with an average of 35 nm in size, and that the stability of silver nanoparticles was due to its high negative zeta potential of –27.6 mV. The current study also revealed that green silver nanoparticles had very good genotoxic and cytotoxic activity in peripheral blood mononuclear cells (PBMCs). Leukemia leads to the development of high numbers of white blood cells, which is one of the major types of cancers that affect children. Many of the chemicals used for the treatment produce remarkable side effects. To overcome this problem, we made an attempt to see the efficacy of latex green silver nanoparticle on peripheral blood mononuclear cells and deoxyribonucleic acid fragmentation, which leads to the development of future therapeutic drugs.

Abstract Background Glossogyne tenuifolia (GT) (Hsiang-ju) is a Chinese herbal medicine previously exhibited an anti-inflammatory activity. This study aimed to investigate the effect of GT ethanol extract (GTE) on T cell-mediated adaptive immunity. Methods Human peripheral blood mononuclear cells (PBMCs) and Jurkat T cells were activated by phytohemagglutinin in the presence of various doses (3.13–50 μg/mL) of GTE. The effect of GTE on T cell activation was examined by a proliferation assay of activated PBMCs and the level of the activation marker CD69 on the surface of activated Jurkat T cells. Apoptosis was determined by propidium iodide staining in hypotonic solution. Signaling pathway molecules were assessed by western blotting. Results Glossogyne tenuifolia ethanol extract was demonstrated to inhibit T cell activation, not only in the proliferation of human PBMCs at the concentrations of 12.5, 25 and 50 μg/mL (P = 0.0118, 0.0030 and 0.0021) but also in the CD69 expression in Jurkat cells, which was not due to the cytotoxicity of GTE. The presence of GTE did not change the activity of nuclear factor kappa-light-chain-enhancer of activated B cells or extracellular signal-regulated kinase upon T cell activation. In addition, GTE significantly reduced activation of c-Jun N-terminal kinase (JNK) (P = 0.0167) and p38 (P = 0.0278). Furthermore, decreased JNK activation mediated the preventive effect of GTE on T cell activation-induced cell death (AICD). Conclusion Glossogyne tenuifolia ethanol extract inhibited T cell activation of Jurkat cells and freshly prepared human PBMCs due to suppression of JNK activity. Furthermore, GTE inhibited AICD by blocking prolonged JNK phosphorylation in activated T cells. Taken together, the anti-inflammatory effects exerted by GTE were mediated via suppression of JNK phosphorylation in T cell activation.

Development of a suitable vaccine against visceral leishmaniasis (VL), a fatal parasitic disease, is considered to be vital for maintaining the success of kala-azar control programs. The fact that Leishmania-infected individuals generate life-long immunity offers a viable proposition in this direction. Our prior studies demonstrated that T-helper1 (Th1) type of cellular response was generated by six potential recombinant proteins viz. elongation factor-2 (elF-2), enolase, aldolase, triose phosphate isomerase (TPI), protein disulfide isomerase (PDI) and p45, derived from a soluble antigenic fraction (89.9–97.1 kDa) of Leishmania (Leishmania) donovani promastigote, in treated Leishmania patients and golden hamsters and showed significant prophylactic potential against experimental VL. Moreover, since, it is well-known that our immune system, in general, triggers production of specific protective immunity in response to a small number of amino acids (peptide), this led to the identification of antigenic epitopes of the above-stated proteins utilizing immunoinformatics. Out of thirty-six, three peptides-P-10 (enolase), P-14, and P-15 (TPI) elicited common significant lymphoproliferative as well as Th1-biased cytokine responses both in golden hamsters and human subjects. Further, immunization with these peptides plus BCG offered 75% prophylactic efficacy with boosted cellular immune response in golden hamsters against Leishmania challenge which is indicative of their candidature as potential vaccine candidates.

Development of a suitable vaccine against visceral leishmaniasis (VL), a fatal parasitic disease, is considered to be vital for maintaining the success of kala-azar control programs. The fact that Leishmania -infected individuals generate life-long immunity offers a viable proposition in this direction. Our prior studies demonstrated that T-helper1 (Th1) type of cellular response was generated by six potential recombinant proteins viz. elongation factor-2 (elF-2), enolase, aldolase, triose phosphate isomerase (TPI), protein disulfide isomerase (PDI) and p45, derived from a soluble antigenic fraction (89.9–97.1 kDa) of Leishmania (Leishmania) donovani promastigote, in treated Leishmania patients and golden hamsters and showed significant prophylactic potential against experimental VL. Moreover, since, it is well-known that our immune system, in general, triggers production of specific protective immunity in response to a small number of amino acids (peptide), this led to the identification of antigenic epitopes of the above-stated proteins utilizing immunoinformatics. Out of thirty-six, three peptides-P-10 (enolase), P-14, and P-15 (TPI) elicited common significant lymphoproliferative as well as Th1-biased cytokine responses both in golden hamsters and human subjects. Further, immunization with these peptides plus BCG offered 75% prophylactic efficacy with boosted cellular immune response in golden hamsters against Leishmania challenge which is indicative of their candidature as potential vaccine candidates. [ABSTRACT FROM AUTHOR]

Inflammatory mediator prostaglandin E2 (PGE2) contributes to bone resorption in several inflammatory conditions including periodontitis. The terminal enzyme, microsomal prostaglandin E synthase‐1 (mPGES‐1) regulating PGE2 synthesis is a promising therapeutic target to reduce inflammatory bone loss. The aim of this study was to investigate effects of mPGES‐1 inhibitors, aminothiazoles TH‐848 and TH‐644, on PGE2 production and osteoclastogenesis in co‐cultures of periodontal ligament (PDL) and osteoclast progenitor cells RAW 264.7, stimulated by lipopolysaccharide (LPS), and bone resorption in RANKL‐mediated peripheral blood mononuclear cells (PBMCs). PDL and RAW 264.7 cells were cultured separately or co‐cultured and treated with LPS alone or in combination with aminothiazoles. Multinucleated cells stained positively for tartrate‐resistant acid phosphatase (TRAP) were scored as osteoclast‐like cells. Levels of PGE2, osteoprotegerin (OPG) and interleukin‐6, as well as mRNA expression of mPGES‐1, OPG and RANKL were analysed in PDL cells. PBMCs were treated with RANKL alone or in combination with aminothiazoles. TRAP‐positive multinucleated cells were analysed and bone resorption was measured by the CTX‐I assay. Aminothiazoles reduced LPS‐stimulated osteoclast‐like cell formation both in co‐cultures and in RAW 264.7 cells. Additionally, aminothiazoles inhibited PGE2 production in LPS‐stimulated cultures, but did not affect LPS‐induced mPGES‐1, OPG or RANKLmRNA expression in PDL cells. In PBMCs, inhibitors decreased both osteoclast differentiation and bone resorption. In conclusion, aminothiazoles reduced the formation of osteoclast‐like cells and decreased the production of PGE2 in co‐cultures as well as single‐cell cultures. Furthermore, these compounds inhibited RANKL‐induced bone resorption and differentiation of PBMCs, suggesting these inhibitors for future treatment of inflammatory bone loss such as periodontitis. [ABSTRACT FROM AUTHOR]

Cross-talk between coding RNAs and regulatory non-coding microRNAs, within human genome, has provided compelling evidence for the existence of flexible checkpoint control of T-Cell activation. The present study attempts to demonstrate that the interplay between miR-2909 and its effector KLF4 gene has the inherent capacity to regulate genes coding for CTLA4, CD28, CD40, CD134, PDL1, CD80, CD86, IL-6 and IL-10 within normal human peripheral blood mononuclear cells (PBMCs). Based upon these findings, we propose a pathway that links miR-2909 RNomics with the genes coding for immune checkpoint regulators required for the maintenance of immune homeostasis. [ABSTRACT FROM AUTHOR]

Abstract: Reducing the activities of the pro‐inflammatory cytokine IL‐17 is an effective treatment strategy for several chronic autoimmune disorders. Rho‐associated coiled‐coil containing kinase 2 (ROCK2) is a member of the serine‐threonine protein kinase family that regulates IL‐17 secretion in T cells via signal transducer and activator of transcription 3 (STAT3)‐dependent mechanism. We reported here that the selective ROCK2 inhibitor KD025 significantly reduced in vitro production of IL‐17 in unfractionated human peripheral blood mononuclear cells (PBMCs) stimulated with the dectin‐1 agonist Candida albicans. C. albicans induced IL‐17 was reduced by 70% (p < 0.0001); a similar reduction (80%) was observed in PBMC stimulated with the Toll‐like receptor 2 agonist Staphylococcus epidermidis (p < 0.0001). Treatment of PBMC with KD025 was not associated with a reduction in IL‐1β, IL‐6 or IL‐1α levels; in contrast, a 1.5 fold increase in the level of IL‐1 receptor antagonist (IL‐1Ra) was observed (p < 0.001). KD025 down‐regulated C. albicans‐induced Myosin Light Chain and STAT3, whereas STAT5 phosphorylation increased. Using anti‐CD3/CD28 activation of the TCR, KD025 similarly suppressed IL‐17 independent of a reduction in IL‐1β. Thus, ROCK2 directly regulates IL‐17 secretion independent of endogenous IL‐1 and IL‐6 supporting development of selective ROCK2 inhibitors for treatment of IL‐17‐driven inflammatory diseases. [ABSTRACT FROM AUTHOR]

The selective modulation of immunity is an emerging concept driven by the vast advances in our understanding of this crucial host defense system. Invertebrates have raised researchers’ interest as potential sources of new bioactive molecules owing to their antibacterial, anticancer and immunomodulatory activities. A LipoPolySaccharide (LPS) challenge in the ascidian Ciona intestinalis generates the transcript, Ci 8 short, with cis -regulatory elements in the 3′ UTR region that are essential for shaping innate immune responses. The derived amino acidic sequence in silico analysis showed specific binding to human Major Histocompatibility Complex (MHC) Class I and Class II alleles. The role of Ci 8 short peptide was investigated in a more evolved immune system using human Peripheral Blood Mononuclear Cells (PBMCs) as in vitro model. The biological activities of this molecule include the activation of 70 kDa TCR ζ chain Associated Protein kinase (ZAP-70) and T Cell Receptor (TCR) Vβ oligo clonal selection on CD4 + T lymphocytes as well as increased proliferation and IFN-γ secretion. Furthermore Ci 8 short affects CD4 + /CD25 high induced regulatory T cells (iTreg) subset selection which co-expressed the functional markers TGF-β1/Latency Associated Protein (LAP) and CD39/CD73. This paper describes a new molecule that modulates important responses of the human adaptive immune system. [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles (NPs) by green route approaches has advantages over conventional methods. In green synthesis, we use eco-friendly plant extracts contain secondary metabolites and bioactive components, proteins that act as both reducing and capping agents, form stable and shape-controlled green silver nanoparticles. The current study deals with the synthesis of silver nanoparticles using the aqueous latex extract of Allamanda cathartica. The green silver nanoparticles are characterized by using different spectroscopic methods like ultra violet-visible spectroscopy (UV-Vis), Fourier transform-infrared spectroscopy (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD). Results indicated that the crystalline natured particles were spherical shaped with an average of 35 nm in size and that the stability of silver nanoparticles was due to its high negative zeta potential of -27.6 mV. The current study also revealed that green silver nanoparticles had very good genotoxic and cytotoxic activity in peripheral blood mononuclear cells (PBMCs). Leukemia leads to the development of high numbers of white blood cells, which is one of the major types of cancers that affect children. Many of the chemicals used for the treatment produce remarkable side effects. To overcome this problem, we made an attempt to see the efficacy of latex green silver nanoparticle on peripheral blood mononuclear cells and deoxyribonucleic acid fragmentation, which leads to the development of future therapeutic drugs. [ABSTRACT FROM AUTHOR]

Candida parapsilosis is one of the most prevalent Candida species; however, the inflammation response induced by C. parapsilosis and related mechanism received few studies. In this study, we analyzed the pro-inflammatory cytokine responses evoked by C. parapsilosis in human peripheral blood mononuclear cells (PBMCs) and THP-1 cells, determined the signal pathways related to the inflammation response and investigated the expression of dectin-1 modified with C. parapsilosis. Exposure of PBMCs and THP-1 cells to C. parapsilosis led to the increased gene expression and production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). C. parapsilosis induced TNF-α and IL-6 release in a time- and dose-dependent manner. Western blotting was used to analyze p38, ERK1/2 mitogen-activated protein kinases (MAPKs) and IκB-α phosphorylation and degradation. Nuclear translocation of NF-κB was detected by confocal microscopy. THP-1 cells challenged by C. parapsilosis resulted in the activation of NF-κB and phosphorylation of p38 and ERK1/2 MAPKs. The expression of dectin-1 was up-regulated after the stimulation of C. parapsilosis. Our results suggest that C. parapsilosis could stimulate the inflammatory response, increase the expression of dectin-1 and activate NF-κB and MAPKs signaling pathways in macrophages. [ABSTRACT FROM AUTHOR]

Polysaccharides were extracted from seven plants endemic to Gabon to study their potential immunological activities. Peripheral blood mononuclear cell (PBMC) (5 × 105 cells/mL) proliferation, cytokine and immunoglobulin G (IgG) assays were performed after stimulation with different concentrations of polysaccharide fractions compared with lipopolysaccharides (LPS) and concanavalin A (ConA) from healthy volunteers. The culture supernatants were used for cytokine and IgG detection by enzyme-linked immunosorbent assay (ELISA). The results show that pectin and hemicellulose extracts from Uvaria klainei, Petersianthus macrocarpus, Trichoscypha addonii, Aphanocalyx microphyllus, Librevillea klaineana, Neochevalierodendron stephanii and Scorodophloeus zenkeri induced production levels that were variable from one individual to another for IL-12 (3–40 pg/mL), IL-10 (6–443 pg/mL), IL-6 (7–370 pg/mL), GM-CSF (3–170 pg/mL) and IFN-γ (5–80 pg/mL). Only hemicelluloses from Aphanocalyx microphyllus produce a small amount of IgG (OD = 0.034), while the proliferation of cells stimulated with these polysaccharides increased up to 318% above the proliferation of unstimulated cells. However, this proliferation of PBMCs was abolished when the pectin of some of these plants was treated with endopolygalacturonase (p < 0.05), but the trend of cytokine synthesis remained the same, both before and after enzymatic treatment or saponification. This study suggests that these polysaccharides stimulate cells in a structure-dependent manner. The rhamnogalacturonan-I (RGI) fragment alone was not able to induce the proliferation of PBMC.

While the role of Toll-like receptors (TLRs) has been investigated in murine models of tegumentary leishmaniasis caused by Leishmania (Viannia) braziliensis , the interaction between TLRs and Leishmania sp. has not been investigated in human cells. The aim of this study was to evaluate the involvement of TLR4 in cytokine production of human peripheral blood mononuclear cells (PBMCs) induced by L. braziliensis , and whether the parasite alters the expression of TLR4 on monocytes/macrophages . Amastigote forms were obtained from mice lesions and PBMCs were isolated from healthy donors. PBMCs were cultured in absence or presence of IFNγ, TLR4 neutralizing antibodies, natural antagonist of TLR4 ( Bartonella LPS), TLR4 agonist ( E. coli LPS), and amastigote forms. The concentrations of tumor necrosis factor (TNFα) and interleukin 10 (IL-10) were assayed by ELISA and TLR4 expression by flow cytometry. Amastigotes forms of L. braziliensis induced TNFα and IL-10 production only in IFNγ-primed PBMCs. The TNFα and IL-10 production was inhibited by TLR4 neutralization, both with anti-TLR4 antibodies and Bartonella LPS. Interestingly, addition of E. coli LPS further increased TNFα but not IL-10 production induced by L. braziliensis amastigotes. Amastigotes of L. braziliensis strongly reduced membrane TLR4 expression on monocytes/macrophages, apparently by internalization after the infection. The present study reveals that TLR4 drives the production of TNFα and IL-10 induced by L. braziliensis amastigotes and that the parasites decrease TLR4 expression on monocyte surface. [ABSTRACT FROM AUTHOR]

Abstract α1-Antitrypsin (AAT) is a member of the serine proteinase inhibitor family that impedes the enzymatic activity of serine proteinases, including human neutrophil elastase, cathepsin G and neutrophil proteinase 3. Here, we expressed recombinant AAT by fusing the intact AAT gene to the constant region of IgG1 to generate soluble recombinant AAT-Fc protein. The recombinant AAT-Fc protein was produced in Chinese hamster ovary (CHO) cells and purified using mini-protein A affinity chromatography. Recombinant AAT-Fc protein was tested for antiinflammatory function and AAT-Fc sufficiently suppressed tumor necrosis factor (TNF)-α-induced interleukin (IL)-6 in human peripheral blood mononuclear cells (PBMCs) and inhibited cytokine-induced TNFα by different cytokines in mouse macrophage Raw 264.7 cells. However, AAT-Fc failed to suppress lipopolysaccharide-induced cytokine production in both PBMCs and macrophages. In addition, our data showed that AAT-Fc blocks the development of hyperglycemia in a streptozotocin-induced mouse model of diabetes. Interestingly, we also found that plasma-derived AAT specifically inhibited the enzymatic activity of elastase but that AAT-Fc had no inhibitory effect on elastase activity.

There exists a general recognition of the fact that post translational modification of CYLD protein through proteolytic cleavage by MALT-1 results in sustained cellular NF-kB activity which is conspicuously found to be associated with cancer in general and hematological malignancies in particular. The present study was directed to understand the contribution of MALT-1 and deubiquitinase CYLD to the initiation of T-cell acute lymphoblastic leukemia (T-ALL). Such a study revealed for the first time that the 35 kDa CYLD cleaved factor generated by MALT-1 mediated proteolytic cleavage was conspicuously present in human T- ALL subjects of pediatric age group. Further, over-expression of this 35 kDa CYLD factor within normal human peripheral blood mononuclear cells had the inherent capacity to program the genome of these cells resulting in T-cell lineage ALL. Based upon these results, we propose that MALT1 inhibitors may be of crucial importance in the treatment of T-ALL subjects of pediatric age group. [ABSTRACT FROM AUTHOR]

Polysaccharides were extracted from seven plants endemic to Gabon to study their potential immunological activities. Peripheral blood mononuclear cell (PBMC) (5 × 105 cells/mL) proliferation, cytokine and immunoglobulin G (IgG) assays were performed after stimulation with different concentrations of polysaccharide fractions compared with lipopolysaccharides (LPS) and concanavalin A (ConA) from healthy volunteers. The culture supernatants were used for cytokine and IgG detection by enzyme-linked immunosorbent assay (ELISA). The results show that pectin and hemicellulose extracts from Uvaria klainei, Petersianthus macrocarpus, Trichoscypha addonii, Aphanocalyx microphyllus, Librevillea klaineana, Neochevalierodendron stephanii and Scorodophloeus zenkeri induced production levels that were variable from one individual to another for IL-12 (3-40 pg/mL), IL-10 (6-443 pg/mL), IL-6 (7-370 pg/mL), GM-CSF (3-170 pg/mL) and IFN-γ (5-80 pg/mL). Only hemicelluloses from Aphanocalyx microphyllus produce a small amount of IgG (OD = 0.034), while the proliferation of cells stimulated with these polysaccharides increased up to 318% above the proliferation of unstimulated cells. However, this proliferation of PBMCs was abolished when the pectin of some of these plants was treated with endopolygalacturonase (p < 0.05), but the trend of cytokine synthesis remained the same, both before and after enzymatic treatment or saponification. This study suggests that these polysaccharides stimulate cells in a structure-dependent manner. The rhamnogalacturonan-I (RGI) fragment alone was not able to induce the proliferation of PBMC. [ABSTRACT FROM AUTHOR]

Royal jelly (RJ) fatty acids have recently been shown to possess various pharmacological and biological activities. In this work, we studied the immunomodulatory effects of 10-hydroxy- trans-2-decenoic acid (10-HDA) and 3,10-dihydroxy-decanoic acid (3,10-DDA), isolated from RJ, using a model of phytohaemagglutinin-activated human peripheral blood mononuclear cells (PBMCs). We showed that higher concentrations (500 μM) of both fatty acids inhibited the proliferation of PBMCs, and the process was followed by a decrease in the production of interleukin-2 (IL-2). 10-HDA at the concentration of 500 μM inhibited the production of IL-1β and tumor necrosis factor-α by stimulated PBMCs, whereas the same dose of 3,10-DDA had no effect on the levels of these cytokines. Regarding T helper (Th) cytokine profile, higher concentration of 10-HDA, in contrast to the lower one (50 μM), inhibited both Th1 and Th2 response, whereas Th17 response was not significantly modulated, as judged by the levels of interferon-γ, IL-5 and IL-17A in culture supernatants, respectively. Lower concentration of 3,10-DDA stimulated Th1 and Th17 responses and inhibited IL-10 production, whereas the higher dose augmented the Th2 response. In conclusion, our results showed a significant, dose-dependent, immunomodulatory effect of RJ fatty acids in vitro, which was also associated with their structure. [ABSTRACT FROM AUTHOR]

Abstract: The effect of polyhydroxylated fullerene (fullerenol), C60(OH)36, on human peripheral blood mononuclear cells (PBMCs) exposed to X-rays was studied. PBMCs untreated and treated for 1h with C60(OH)36 at the concentrations 75 and 150mg/l were exposed to high doses of ionizing radiation (10, 30 and 50Gy). After 24 and 48h of post-irradiation incubation the viability and granularity of lymphocytes were determined applying the flow cytometry (FC) method. Moreover, after 24h of incubation the membrane fluidity was investigated by measuring the fluorescence anisotropy of a 1,6-diphenyl-1,3,5-hexatriene (DPH) probe. Additionally, DNA damage of PBMCs after exposure to X-rays at the doses 0, 5, 10 and 15Gy in the absence and presence of fullerenol (75mg/l) was determined using the comet assay under alkaline conditions. Results show that the effects of fullerenol C60(OH)36 on X-irradiated human PBMCs are very small or inexistent. It was suggested that this action of C60(OH)36 may be related to its interactions with the surface of plasma membrane but not inside PBMCs. [Copyright &y& Elsevier]

Abstract: In vitro antigen stimulation of peripheral blood mononuclear cells (PBMCs) does not induce immunoglobulin (Ig) production. However, pretreatment of PBMCs with l-leucyl-l-leucine methyl ester (LLME) prior to in vitro stimulation removes the suppression of Ig production. In the present study, we attempted to identify the target cells of LLME and determine the mechanisms by which Ig production in PBMCs is suppressed. We found that CD14+ monocytes are involved in the suppression of Ig production in PBMCs. Furthermore, we confirmed that heavy-chain ferritin derived from CD14+ monocytes suppresses Ig production in PBMCs, possibly through iron sequestration. [Copyright &y& Elsevier]

Fasciola hepatica is a trematode worm that causes fascioliasis, a neglected tropical disease in humans and livestock. To gain insight into the host-parasite interactions that facilitate infection, we have investigated the immunomodulatory properties of the parasite's tegumental coat (FhTeg), a major antigen source that is sloughed off and renewed every 2–3 h as the worm migrates through host tissue. Using mouse models of infection, we have previously shown that FhTeg induces a novel phenotype of dendritic cells that induce anergic CD4+ T-cells. We proposed that this induced state of hyporesponsiveness characterised by suppression of cell proliferation and cytokine secretion was one mechanism by which F. hepatica prevented host protective immunity to support the parasite survival. To determine if the same mechanisms are utilised during human infections, we have now examined the interaction of FhTeg with human PBMCs. FhTeg binds to and modulates cytokine production in human PBMCs, in particular targeting the CD4+ population resulting in reduced levels of TNF, IL-2 and IFNγ and increased markers of anergy. Furthermore, the adoptive transfer of FhTeg stimulated PBMCs to a humanised model of acute graft versus host disease (GvHD) attenuated disease progression by increasing survival and reducing pathological scores. These mice also displayed a significant decrease in the total number of human CD4+ cells expressing TNF, IL-2 and IFNγ in the spleen, liver and lung. This study therefore concurs with evidence from ruminant and murine models of infection suggesting that anergic CD4+ T cells are associated with successful Fasciola hepatica infection and highlights an important role for FhTeg in contributing to the overall immunosuppressive effects of this parasite. [Display omitted] [ABSTRACT FROM AUTHOR]

Analysis of phosphorylated histone protein H2AX (γH2AX) foci is currently the most sensitive method to detect DNA double-strand breaks (DSB). This protein modification has the potential to become an individual biomarker of cellular stress, especially in the diagnosis and monitoring of neoplastic diseases. To make γH2AX foci analysis available as a routine screening method, different software approaches for automated immunofluorescence pattern evaluation have recently been developed. In this study, we used novel pattern recognition algorithms on the AKLIDES® platform to automatically analyze immunofluorescence images of γH2AX foci and compared the results with visual assessments. Dose- and time-dependent γH2AX foci formation was investigated in human peripheral blood mononuclear cells (PBMCs) treated with the chemotherapeutic drug etoposide (ETP). Moreover, the AKLIDES system was used to analyze the impact of different immunomodulatory reagents on γH2AX foci formation in PBMCs. Apart from γH2AX foci counting the use of novel pattern recognition algorithms allowed the measurement of their fluorescence intensity and size, as well as the analysis of overlapping γH2AX foci. The comparison of automated and manual foci quantification showed overall a good correlation. After ETP exposure, a clear dose-dependent increase of γH2AX foci formation was evident using the AKLIDES as well as Western blot analysis. Kinetic experiments on PBMCs incubated with 5 μM ETP demonstrated a peak in γH2AX foci formation after 4 to 8 h, while a removal of ETP resulted in a strong reduction of γH2AX foci after 1 to 4 h. In summary, this study demonstrated that the AKLIDES system can be used as an efficient automatic screening tool for γH2AX foci analysis by providing new evaluation features and facilitating the identification of drugs which induce or modulate DNA damage. © 2013 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Kynurenine monooxygenase (KMO) catalyzes the conversion of kynurenine to 3-hydroxykynurenine. Modulation of KMO activity has been implicated in several neurodegenerative diseases, including Huntington disease. Our goal is to develop potent and selective small-molecule KMO inhibitors with suitable pharmacokinetic characteristics for in vivo proof-of-concept studies and subsequent clinical development. We developed a comprehensive panel of biochemical and cell-based assays that use liquid chromatography/tandem mass spectrometry to quantify unlabeled kynurenine and 3-hydroxykynurenine. We describe assays to measure KMO inhibition in cell and tissue extracts, as well as cellular assays including heterologous cell lines and primary rat microglia and human peripheral blood mononuclear cells. [ABSTRACT FROM PUBLISHER]

Context: Aflatoxins (AFs) are highly hazardous carcinogenic mycotoxins originated from very common fungi present in the environment. Their effect on key immune-surveillance molecules is unclear. Objective: We aimed to examine the effect of mixed AFs on immunologically relevant molecules and on viability in human peripheral blood mononuclear cells (PBMCs), in conditions similar to those occurring naturally, i.e. using a mixture of environmentally relevant levels of AFB1, AFB2, AFG1 and AFG2. Materials and methods: We evaluated the mRNA expression of MyD88, toll-like receptor (TLR)-2, TLR4 and CD14, in human PBMCs treated with a mixture of AFB1, AFB2, AFG1 and AFG2 at different doses for 2, 12 and 24 h. We used qRT-PCR to assess changes in transcripts of MyD88, TLR2, TLR4 and CD14 in PBMCs. We also evaluated the viability of PBMCs exposed to AFs. Results: Biologically relevant levels of mixed AFs elicited early immune modulation in human PBMCs. qRT-PCR results showed several folds increase of MyD88, TLR2, TLR4 and CD14 transcripts in PBMCs as early as 2 h post-exposure to mixed AFs. Kinetics and dose-response of the up-regulation differed for mentioned gene transcripts. Further, prolonged exposure to mixed AFs decreased PBMCs viability. Conclusion: Immunotoxicity of AFs on PBMCs may be mediated by up-regulation of key immune-surveillance molecule transcripts. The description of these effects induced by AFs on PBMCs are novel and should be taken into account when considering AF-related infectious and noninfectious diseases in areas highly exposed to AFs. [ABSTRACT FROM AUTHOR]

Synthetic C-reactive protein (CRP) rescues mice from lethal endotoxin shock or bacterial infection by suppressing tumor necrosis factor (TNF-α), but in turn, enhances Kupffer cell phagocytic activity. We herein assessed the influence of CRP in human peripheral blood mononuclear cells (PBMCs). When human PBMCs were stimulated in vitro with penicillin-treated Streptococcus pyogenes, bacterial DNA motifs and lipopolysaccharide with or without synthetic CRP, CRP suppressed the production of TNF-α and IL-12, but not that of IFN-γ. This was also the case for the in vitro Shwartzman reaction induced in PBMCs. CRP also decreased high-mobility group box 1 production from macrophages, which is crucial in the later phase of endotoxin/septic shock. However, CRP upregulated the perforin expression by CD56 NK cells and increased their antitumor cytotoxicity. CRP may thus be a potent immunomodulatory factor in the human immune system, suggesting its therapeutic potential for use against human septic shock. [ABSTRACT FROM AUTHOR]

Abstract: Arsenic through its ability to regulate genes that link cell cycle control with apoptosis has been widely recognized to play a crucial role in oncogenomics. However, the molecular event by which arsenic affects such genes is far from clear. Here we provide reasonably good evidence to support the view that arsenic exposure to human PBMCs (peripheral blood mononuclear cells) at low concentrations results in the over-expression of miR-2909 within these cells. This over-expressed miR-2909 was found to regulate CCND1 (Cyclin D1) gene expression, within these cells by inducing splice-switching of tumor suppresser CYLD (Cylindromatosis) gene as well as modulation of SP1 (Specificity Protein 1) activity through the repression of KLF4 (Kruppel-like factor4) expression at the translational level. Arsenic dependent regulation of AATF (Apoptosis Antagonizing Transcription factor) and BCL3 (B-cell Lymphoma 3) were also found to be modulated through its capacity to induce miR-2909 expression. Based upon these observations, a novel epigenomic pathway was proposed which may not only be useful in understanding the paradoxical role of arsenic in oncogenomics but also may even be useful in devising various strategies for the treatment/prevention of tumors induced by arsenic. [Copyright &y& Elsevier]

Summary: In spite of reports on cytokines induction by the Brucella DNA in murine model, there is no comparison between pathogenic and appropriate vaccine strains in human. We investigated the cytokines profile of human peripheral blood mononuclear cells (PBMCs) induced by DNA extracted from pathogenic isolates of Brucella melitensis and B. abortus as well as Rev1 and S19; the appropriate vaccine strains. It was observed that despite differential induction of Interleukin(IL)-12 and IL-10 production, identical IL-12/IL-10 concentration ratio was obtained by all Brucella strains DNAs that was 2 after 24h and 4 after 5 days of incubation. In addition, IL-2 and Interferon(IFN)-γ production were profoundly increased compared to the medium at day 3 and 5 respectively but IFN-α was not induced. Therefore, Brucella strains DNAs are Th1 inducing component with similar pattern in human PBMCs. [Copyright &y& Elsevier]

Glutathione (GSH), the most prevalent intracellular non-protein thiol, plays an important role in the interleukin-2 (IL-2)-induced proliferative activity of normal and tumour cells expressing IL-2 receptor (IL-2R). In the present study, we investigate the effect of IL-2 on proliferation of the human melanoma A375 cell line, and the possible selective cytomodulation effect of this cytokine by l-2-oxothiazolidine-4-carboxylate (OTZ) on these melanoma cells and on human peripheral blood mononuclear cells (PBMCs). We found that recombinant IL-2 (rIL-2) significantly increased the proliferation rate of A375 melanoma cells, which was associated with an increase in GSH levels, the enhancement of IL-2Rα expression and the endogenous production of IL-2 in these tumour cells. In contrast, OTZ decreased GSH content and the proliferation rate of A375 cells, and abrogated the growth-promoting effects of rIL-2. Thus, compared to cells treated with rIL-2, pre-treatment with OTZ reduced IL-2Rα expression, and also decreased the consumption of rIL-2 and the endogenous secretion of IL-2 by these tumour cells. With regard to PBMCs, the combination of OTZ plus rIL-2 resulted in a more rapid and greater increase of IL-2Rα expression than rIL-2 alone, with the proliferation rate being similar in the first 24 h, but with a lower PBMC′ count found thereafter compared to rIL-2 treatment alone. These results suggest that OTZ plays a crucial role in obtaining a selective cytomodulation of rIL-2, enabling it to exert its growth-promoting effect on normal cells, but not on melanoma cells, thereby possibly improving biochemotherapy with rIL-2. [ABSTRACT FROM AUTHOR]

Myeloid lineage cells use TLRs to recognize and respond to diverse microbial ligands. Although unique transcription factors dictate the outcome of specific TLR signaling, whether lineage-specific differences exist to further modulate the quality of TLR-induced inflammation remains unclear. Comprehensive analysis of global gene transcription in human monocytes, monocyte-derived macrophages, and monocyte-derived dendritic cells stimulated with various TLR ligands identifies multiple lineage-specific, TLR-responsive gene programs. Monocytes are hyperresponsive to TLR7/8 stimulation that correlates with the higher expression of the receptors. While macrophages and monocytes express similar levels of TLR4, macrophages, but not monocytes, upregulate interferon-stimulated genes (ISGs) in response to TLR4 stimulation. We find that TLR4 signaling in macrophages uniquely engages transcription factor IRF1, which facilitates the opening of ISG loci for transcription. This study provides a critical mechanistic basis for lineage-specific TLR responses and uncovers IRF1 as a master regulator for the ISG transcriptional program in human macrophages. [Display omitted] • Human myeloid cells show lineage-specific transcriptional responses to TLR activation • Monocytes display an exaggerated pro-inflammatory profile in response to TLR8 ligand • TLR4 engagement elicits robust ISG response in macrophages but not in monocytes • IRF1 governs chromatin accessibility at ISG loci in TLR4-stimulated macrophages Song et al. examine the responses of human myeloid populations to bacterial and viral ligands and discover the lineage-specific induction of pro-inflammatory gene expression. TLR4 signaling in macrophages, but not monocytes, enables nuclear translocation of IRF1, which acts as a pioneer transcription factor to increase the chromatin accessibility of IFNB1 and ISG loci. [ABSTRACT FROM AUTHOR]

In the present research, a lipophilic methotrexate (MTX) prodrug was developed by covalent conjugating of MTX to stearic acid (SA) as a lipid moiety via amid bond. The structure of synthesized conjugate, MTX-SA, was confirmed by IR and NMR spectra. To evaluate inflammatory response of MTX-SA conjugate and MTX, human PBMCs were isolated and exposed to 50, 500 and 5000 nM of MTX-SA conjugate and free MTX. The expression of four key genes involved in inflammation and apoptosis including IL-8, IL-1β, IL-10 and Bcl2 depicted that the MTX-SA had controversial behavior in different doses on the inflammatory transcription. Also, MTX-SA statically decreased the number of immune live cells in comparison to MTX. However, MTX-SA did not capture PBMCs cell cycle in G0/G1 phase. Totally, these results showed MTX-SA with long lipid chain has different effect on immune responses and it is irrefutable that detailed studies of its immunotoxicity and immunogenicity ought to be taken into account. [ABSTRACT FROM AUTHOR]

Inflammatory mediator prostaglandin E 2 (PGE 2 ) contributes to bone resorption in several inflammatory conditions including periodontitis. The terminal enzyme, microsomal prostaglandin E synthase-1 (mPGES-1) regulating PGE 2 synthesis is a promising therapeutic target to reduce inflammatory bone loss. The aim of this study was to investigate effects of mPGES-1 inhibitors, aminothiazoles TH-848 and TH-644, on PGE 2 production and osteoclastogenesis in co-cultures of periodontal ligament (PDL) and osteoclast progenitor cells RAW 264.7, stimulated by lipopolysaccharide (LPS), and bone resorption in RANKL-mediated peripheral blood mononuclear cells (PBMCs). PDL and RAW 264.7 cells were cultured separately or co-cultured and treated with LPS alone or in combination with aminothiazoles. Multinucleated cells stained positively for tartrate-resistant acid phosphatase (TRAP) were scored as osteoclast-like cells. Levels of PGE 2 , osteoprotegerin (OPG) and interleukin-6, as well as mRNA expression of mPGES-1, OPG and RANKL were analysed in PDL cells. PBMCs were treated with RANKL alone or in combination with aminothiazoles. TRAP-positive multinucleated cells were analysed and bone resorption was measured by the CTX-I assay. Aminothiazoles reduced LPS-stimulated osteoclast-like cell formation both in co-cultures and in RAW 264.7 cells. Additionally, aminothiazoles inhibited PGE 2 production in LPS-stimulated cultures, but did not affect LPS-induced mPGES-1, OPG or RANKL mRNA expression in PDL cells. In PBMCs, inhibitors decreased both osteoclast differentiation and bone resorption. In conclusion, aminothiazoles reduced the formation of osteoclast-like cells and decreased the production of PGE 2 in co-cultures as well as single-cell cultures. Furthermore, these compounds inhibited RANKL-induced bone resorption and differentiation of PBMCs, suggesting these inhibitors for future treatment of inflammatory bone loss such as periodontitis., (© 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

The prevalence of Candida infection induced by non-albicans Candida (NAC) species is increasing. However, as a common NAC species, C. tropicalis has received much less study in terms of host immunity than C. albicans has. In this study, we evaluated the pro-inflammatory cytokine responses evoked by C. tropicalis and determined whether dectin-1 and downstream NF-κB and mitogen-activated protein kinases (MAPKs) signaling pathways played roles in inflammation in human peripheral blood mononuclear cells (PBMCs) and THP-1 macrophage-like cells. Exposure of PBMCs and THP-1 macrophage-like cells to C. tropicalis led to the enhanced gene expression and secretion of TNF-α and IL-6 in a time- and dose-dependent manner. THP-1 macrophage-like cells being challenged by C. tropicalis resulted in the activation of the NF-κB, p38, and ERK1/2 MAPK signaling pathways. We also found that the expression of dectin-1 was increased with C. tropicalis treatment. These data reveal that dectin-1 may play a role in sensing the inflammation response induced by C. tropicalis and that NF-κB and MAPK are involved in the downstream signaling pathways in macrophages.

While the role of Toll-like receptors (TLRs) has been investigated in murine models of tegumentary leishmaniasis caused by Leishmania (Viannia) braziliensis, the interaction between TLRs and Leishmania sp. has not been investigated in human cells. The aim of this study was to evaluate the involvement of TLR4 in cytokine production of human peripheral blood mononuclear cells (PBMCs) induced by L. braziliensis, and whether the parasite alters the expression of TLR4 on monocytes/macrophages. Amastigote forms were obtained from mice lesions and PBMCs were isolated from healthy donors. PBMCs were cultured in absence or presence of IFNγ, TLR4 neutralizing antibodies, natural antagonist of TLR4 (Bartonella LPS), TLR4 agonist (E. coli LPS), and amastigote forms. The concentrations of tumor necrosis factor (TNFα) and interleukin 10 (IL-10) were assayed by ELISA and TLR4 expression by flow cytometry. Amastigotes forms of L. braziliensis induced TNFα and IL-10 production only in IFNγ-primed PBMCs. The TNFα and IL-10 production was inhibited by TLR4 neutralization, both with anti-TLR4 antibodies and Bartonella LPS. Interestingly, addition of E. coli LPS further increased TNFα but not IL-10 production induced by L. braziliensis amastigotes. Amastigotes of L. braziliensis strongly reduced membrane TLR4 expression on monocytes/macrophages, apparently by internalization after the infection. The present study reveals that TLR4 drives the production of TNFα and IL-10 induced by L. braziliensis amastigotes and that the parasites decrease TLR4 expression on monocyte surface., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The Deubiquitinating enzyme, Cylindromatosis (CYLD), has been established as a crucial regulator of B-cells. The present study was addressed to identify the nature of CYLD-dependent RNomics in patients of pediatric age group with B-ALL. The study revealed the presence of a novel mutant CYLD of 55 kDa in these patients. The mutant CYLD displayed its ability to restrict the cells in G2 phase of cell cycle, down-regulate PLK-1 and block the nuclear translocation of BCL3. Based upon these results, we propose that this mutant CYLD has the capacity to act as a differential marker characteristic of B-cell lymphoblastic leukemia. Pediatr Blood Cancer 2015;62:1066-1069. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)