Molecular and functional changes in neutrophilic granulocytes induced by nicotine: a systematic review and critical evaluation.

Background: Over 1.1 billion people smoke worldwide. The alkaloid nicotine is a prominent and addictive component of tobacco. In addition to tumors and cardiovascular disorders, tobacco consumption is associated with a variety of chronic-inflammatory diseases. Although neutrophilic granulocytes (neutrophils) play a role in the pathogenesis of many of these diseases, the impact of nicotine on neutrophils has not been systematically reviewed so far. Objectives: The aim of this systematic review was to evaluate the direct influence of nicotine on human neutrophil functions, specifically on cell death/damage, apoptosis, chemotaxis, general motility, adhesion molecule expression, eicosanoid synthesis, cytokine/chemokine expression, formation of neutrophil extracellular traps (NETs), phagocytosis, generation of reactive oxygen species (ROS), net antimicrobial activity, and enzyme release. Material and methods: This review was conducted according to the PRISMA guidelines. A literature search was performed in the databases NCBI Pubmed® and Web of Science™ in February 2023. Inclusion criteria comprised English written research articles, showing in vitro studies on the direct impact of nicotine on specified human neutrophil functions. Results: Of the 532 originally identified articles, data from 34 articles were finally compiled after several evaluation steps. The considered studies highly varied in methodological aspects. While at high concentrations (>3 mmol/l) nicotine started to be cytotoxic to neutrophils, concentrations typically achieved in blood of smokers (in the nmol/l range) applied for long exposure times (24-72h) supported the survival of neutrophils. Smoking-relevant nicotine concentrations also increased the chemotaxis of neutrophils towards several chemoattractants, elevated their production of elastase, lipocalin-2, CXCL8, leukotriene B4 and prostaglandin E2, and reduced their integrin expression. Moreover, while nicotine impaired the neutrophil phagocytotic and anti-microbial activity, a range of studies demonstrated increased NET formation. However, conflicting effects were found on ROS generation, selectin expression and release of ß-glucuronidase and myeloperoxidase. Conclusion: Nicotine seems to support the presence in the tissue and the inflammatory and selected tissue-damaging activity of neutrophils and reduces their antimicrobial functions, suggesting a direct contribution of nicotine to the pathogenesis of chronic-inflammatory diseases via influencing the neutrophil biology.

Extracellular Matrix Oxidised by the Granulocyte Oxidants Hypochlorous and Hypobromous Acid Reduces Lung Fibroblast Adhesion and Proliferation In Vitro.

Chronic airway inflammation and oxidative stress play crucial roles in the pathogenesis of chronic inflammatory lung diseases, with airway inflammation being a key driving mechanism of oxidative stress in the lungs. Inflammatory responses in the lungs activate neutrophils and/or eosinophils, leading to the generation of hypohalous acids (HOX). These HOX oxidants can damage the extracellular matrix (ECM) structure and may influence cell-ECM interactions. The ECM of the lung provides structural, mechanical, and biochemical support for cells and determines the airway structure. One of the critical cells in chronic respiratory disease is the fibroblast. Thus, we hypothesised that primary human lung fibroblasts (PHLF) exposed to an oxidised cell-derived ECM will result in functional changes to the PHLF. Here, we show that PHLF adhesion, proliferation, and inflammatory cytokine secretion is affected by exposure to HOX-induced oxidisation of the cell-derived ECM. Furthermore, we investigated the impact on fibroblast function from the presence of haloamines in the ECM. Haloamines are chemical by-products of HOX and, like the HOX, haloamines can also modify the ECM. In conclusion, this study revealed that oxidising the cell-derived ECM might contribute to functional changes in PHLF, a key mechanism behind the pathogenesis of inflammatory lung diseases.

Targeting CAMKK2 and SOC Channels as a Novel Therapeutic Approach for Sensitizing Acute Promyelocytic Leukemia Cells to All-Trans Retinoic Acid.

Calcium ions (Ca2+) play important and diverse roles in the regulation of autophagy, cell death and differentiation. Here, we investigated the impact of Ca2+ in regulating acute promyelocytic leukemia (APL) cell fate in response to the anti-cancer agent all-trans retinoic acid (ATRA). We observed that ATRA promotes calcium entry through store-operated calcium (SOC) channels into acute promyelocytic leukemia (APL) cells. This response is associated with changes in the expression profiles of ORAI1 and STIM1, two proteins involved in SOC channels activation, as well as with a significant upregulation of several key proteins associated to calcium signaling. Moreover, ATRA treatment of APL cells led to a significant activation of calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) and its downstream effector AMP-activated protein kinase (AMPK), linking Ca2+ signaling to autophagy. Pharmacological inhibition of SOC channels and CAMKK2 enhanced ATRA-induced cell differentiation and death. Altogether, our results unravel an ATRA-elicited signaling pathway that involves SOC channels/CAMKK2 activation, induction of autophagy, inhibition of cellular differentiation and suppression of cell death. We suggest that SOC channels and CAMKK2 may constitute novel drug targets for potentiating the anti-cancer effect of ATRA in APL patients.

Selective Biological Effects of Selenium-Enriched Polysaccharide (Se-Le-30) Isolated from Lentinula edodes Mycelium on Human Immune Cells.

A common edible mushroom Lentinula edodes, is an important source of numerous biologically active substances, including polysaccharides, with immunomodulatory and antitumor properties. In the present work, the biological activity of the crude, homogenous (Se)-enriched fraction (named Se-Le-30), which has been isolated from L. edodes mycelium by a modified Chihara method towards human peripheral blood mononuclear cells (PBMCs) and peripheral granulocytes, was investigated. The Se-Le-30 fraction, an analog of lentinan, significantly inhibited the proliferation of human PBMCs stimulated with anti-CD3 antibodies or allostimulated, and down-regulated the production of tumor necrosis factor (TNF)-α by CD3+ T cells. Moreover, it was found that Se-Le-30 significantly reduced the cytotoxic activity of human natural killer (NK) cells. The results suggested the selective immunosuppressive activity of this fraction, which is non-typical for mushroom derived polysaccharides.

Immunosuppressive effects and mechanisms of three myeloid-derived suppressor cells subsets including monocytic-myeloid-derived suppressor cells, granulocytic-myeloid-derived suppressor cells, and immature-myeloid-derived suppressor cells.

CONTEXT: Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immune cells of myeloid lineage. Recent reports have suggested that human MDSC are divided into three subsets: monocytic MDSC (M-MDSC), granulocytic MDSC (G-MDSC), and immature MDSC (I-MDSC). However, the characteristics of each human MDSC subset still remain unclear. MATERIALS AND METHODS: To evaluate the immunosuppressive effects and mechanisms, we first performed a T-cell suppression assay using cells obtained from healthy donor peripheral blood samples. The levels of immune inhibitory molecules in the culture supernatant of each MDSC subset were measured to reveal the T-cell suppressive mechanisms. Then, we compared these results with the results from cells obtained from cancer patient blood samples. Finally, we investigated the difference in the frequency of each MDSC subset between the healthy donors and the cancer patients. RESULTS: Although M-MDSC and G-MDSC suppressed T-cell activation, I-MDSC had no T-cell suppressive effect. We found that the culture supernatant of M-MDSC and G-MDSC contained high levels of interleukin-1 receptor antagonist (IL-1RA) and arginase, respectively, in both healthy donors and cancer patients. No inhibitory molecules were detected in the culture supernatant of I-MDSC. The population of functional MDSC (M-MDSC and G-MDSC) in the total MDSC was significantly increased in cancer patients compared with that in healthy donors. CONCLUSIONS: Although M-MDSC and G-MDSC, which released IL-1RA and arginase, respectively, suppressed T-cell activation, I-MDSC did not have an immunosuppressive effect. The population of functional MDSC was increased in cancer patients compared with that in healthy donors.

Inhibition of the PI3K/mTOR Pathway in Breast Cancer to Enhance Response to Immune Checkpoint Inhibitors in Breast Cancer.

OBJECTIVES: Inhibition of the PI3K/mTOR pathway suppresses breast cancer (BC) growth, enhances anti-tumor immune responses, and works synergistically with immune checkpoint inhibitors (ICI). The objective here was to identify a subclass of PI3K inhibitors that, when combined with paclitaxel, is effective in enhancing response to ICI. METHODS: C57BL/6 mice were orthotopically implanted with syngeneic luminal/triple-negative-like PyMT cells exhibiting high endogenous PI3K activity. Tumor growth in response to treatment with anti-PD-1 + anti-CTLA-4 (ICI), paclitaxel (PTX), and either the PI3Kα-specific inhibitor alpelisib, the pan-PI3K inhibitor copanlisib, or the broad spectrum PI3K/mTOR inhibitor gedatolisib was evaluated in reference to monotherapy or combinations of these therapies. Effects of these therapeutics on intratumoral immune populations were determined by multicolor FACS. RESULTS: Treatment with alpelisib + PTX inhibited PyMT tumor growth and increased tumor-infiltrating granulocytes but did not significantly affect the number of tumor-infiltrating CD8+ T cells and did not synergize with ICI. Copanlisib + PTX + ICI significantly inhibited PyMT growth and increased activation of intratumoral CD8+ T cells as compared to ICI alone, yet did not inhibit tumor growth more than ICI alone. In contrast, gedatolisib + ICI resulted in significantly greater inhibition of tumor growth compared to ICI alone and induced durable dendritic-cell, CD8+ T-cell, and NK-cell responses. Adding PTX to this regimen yielded complete regression in 60% of tumors. CONCLUSION: PI3K/mTOR inhibition plus PTX heightens response to ICI and may provide a viable therapeutic approach for treatment of metastatic BC.

Thymol regulates the functions of immune cells in the rat peritoneal cavity after l-arginine-induced pancreatitis.

AIMS: The present study aimed to evaluate the protective action of thymol towards l-arginine-induced acute pancreatitis (AP) by studying the function of rat peritoneal immune cells. MAIN METHODS: Rat peritoneal exudate cells (PECs), obtained 24 h after the injection of l-arginine (350 mg/100 g of b.w.), were evaluated for mitochondrial activity (MTT assay), adherence capacity (methylene-blue assay), and phagocyte enzyme activity (myeloperoxidase, MPO, assay). The activity of α-amylase and free MPO, as well as the concentration of reactive oxygen species (ROS, i.e. O2-), were determined in the peritoneal exudate fluid. Also, serum α-amylase activity determination and pancreatic tissue pathohistological analysis were performed. KEY FINDING: The administered thymol (50 and 100 mg/kg, per os) caused a significant decrease in the PEC mitochondrial activity and adherence capacity when compared with these functions of PECs isolated from rats with AP. A decrease in cellular MPO activity, as well as in the levels of ROS, α-amylase, and free MPO in peritoneal exudates was found in animals treated with thymol compared to the control animals with AP. Additionally, thymol administration prevented an increase in serum α-amylase activity, accompanied by the decrease in pancreatic tissue damage that follows l-arginine application. SIGNIFICANCE: The present results showed that thymol exerts significant immunomodulatory properties and a potential to silence PEC functions in inflammatory conditions such as the AP induced by l-arginine.

The dynamicity of acute ozone-induced systemic leukocyte trafficking and adrenal-derived stress hormones.

Ozone exposure induces neuroendocrine stress response, which causes lymphopenia. It was hypothesized that ozone-induced increases in stress hormones will temporally follow changes in circulating granulocytes, monocytes- and lymphocyte subpopulations. The goal of this study was to chronicle the changes in circulating stress hormones, cytokines, and leukocyte trafficking during 4 h exposure to ozone. Male Wistar Kyoto rats were exposed to air or ozone (0.4 or 0.8 ppm) for 0.5, 1, 2, or 4 h. After each time point, circulating stress hormones, cytokines, and lung gene expression were assessed along with live and apoptotic granulocytes, monocytes (classical and non-classical), and lymphocytes (B, Th, and Tc) in blood, thymus, and spleen using flow cytometry. Circulating stress hormones began to increase at 1 h of ozone exposure. Lung expression of inflammatory cytokines (Cxcl2, Il6, and Hmox1) and glucocorticoid-responsive genes (Nr3c1, Fkbp5 and Tsc22d3) increased in both a time- and ozone concentration-dependent manner. Circulating granulocytes increased at 0.5 h of ozone exposure but tended to decrease at 2 and 4 h, suggesting a rapid egress and then margination to the lung. Classical monocytes decreased over 4 h of exposure periods (∼80 % at 0.8 ppm). B and Tc lymphocytes significantly decreased after ozone exposure at 2 and 4 h. Despite dynamic shifts in circulating immune cell populations, few differences were measured in serum cytokines. Ozone neither increased apoptotic cells nor altered thymus and spleen lymphocytes. The data show that ozone-induced increases in adrenal-derived stress hormones precede the dynamic migration of circulating immune cells, likely to the lung to mediate inflammation.

Ze-Qi-Tang Formula Induces Granulocytic Myeloid-Derived Suppressor Cell Apoptosis via STAT3/S100A9/Bcl-2/Caspase-3 Signaling to Prolong the Survival of Mice with Orthotopic Lung Cancer.

Non-small-cell lung cancer (NSCLC) remains the most common malignancy with the highest morbidity and mortality worldwide. In our previous study, we found that a classic traditional Chinese medicine (TCM) formula Ze-Qi-Tang (ZQT), which has been used in the treatment of respiratory diseases for thousands of years, could directly inhibit the growth of human NSCLC cells via the p53 signaling pathway. In this study, we explored the immunomodulatory functions of ZQT. We found that ZQT significantly prolonged the survival of orthotopic lung cancer model mice by modulating the tumor microenvironment (TME). ZQT remarkably reduced the number of MDSCs (especially G-MDSCs) and inhibited their immunosuppressive activity by inducing apoptosis in these cells via the STAT3/S100A9/Bcl-2/caspase-3 signaling pathway. When G-MDSCs were depleted, the survival promotion effect of ZQT and its inhibitory effect on lung luminescence signal disappeared in tumor-bearing mice. This is the first study to illustrate the immunomodulatory effect of ZQT in NSCLC and the underlying molecular mechanism.

Hematopoietic stem progenitor cells lacking HLA differ from those lacking GPI-anchored proteins in the hierarchical stage and sensitivity to immune attack in patients with acquired aplastic anemia.

To characterize glycosylphosphatidylinositol-anchored protein-deficient (GPI[-]) and HLA-class I allele-lacking (HLA[-]) hematopoietic stem progenitor cells (HSPCs) in acquired aplastic anemia (AA), we studied the peripheral blood (PB) of 56 AA patients in remission who possessed both (n = 13, Group A) or either GPI(-) (n = 34, Group B) and HLA(-) (n = 9, Group C) cell populations. Seventy-seven percent (10/13) of Group A had HLA(-) cells in all lineages of PB cells, including platelets, while only 23% (3/13) had GPI(-) cells in all lineages, and the median percentage of HLA(-) granulocytes in the total granulocytes (21.2%) was significantly higher than that of GPI(-) granulocytes (0.28%, P < 0.05). The greater lineage diversity in HLA(-) cells than in GPI(-) cells was also seen when Group B and Group C were compared. Longitudinal studies of seven patients in Group A showed a gradual decrease in the percentage of HLA(-) granulocytes, with a reciprocal increase in the GPI(-) granulocytes in four patients responding to cyclosporine (CsA) and an increase in the HLA(-) granulocytes with a stable or declining GPI(-) granulocytes in three patients in sustained remission off CsA therapy. These findings suggest that HLA(-) HSPCs differ from GPI(-) HSPCs in the hierarchical stage and sensitivity to immune attack in AA.

Calcium activity in response to nAChR ligands in murine bone marrow granulocytes with different Gr-1 expression.

Polymorphonuclear neutrophilic granulocytes (PMNs) are the largest proportion of leukocytes in adult human blood that perform numerous functions, including phagocytosis, degranulation, generation of reactive oxygen species, and NETosis. Excessive neutrophil activity associates with hyperinflammation and tissue damage during pathologies such as inflammatory bowel disease, diabetes mellitus, tuberculosis, and coronavirus disease 2019. Nicotinic acetylcholine receptors (nAChRs) can modulate immune cells, including neutrophils, functions, therefore, nAChR ligands are considered as the potent agents for therapy of inflammation. Earlier it was shown, that about 30% of PMNs from the acute inflammatory site responded to nicotine by calcium spikes. In this study, we studied the generation of calcium spikes in murine granulocytes with different maturity level (evaluated by Gr-1 expression) isolated from bone marrow in response to ligands of nAChRs in control and under chronic nicotine consumption. It was found that nearly 20%-25% cells in the granulocyte population responded to nicotine or selective antagonists of different type of nAChRs (α-cobratoxin, GIC, and Vc1.1). We demonstrated that in the control group Ca2+ -mobilizing activity was regulated through α7 and α9α10 nAChRs in immature granulocytes (Gr-1int ), whereas in mature granulocytes (Gr-1hi ) it was regulated through α7, α3ß2, and α9-contained nAChRs. Sensitivity of PMNs to nicotine depended on their maturity level after chronic nicotine consumption. Gr-1int cells responded to nicotine through α7 and α9-contained nAChRs, while Gr-1hi did not respond to nicotine. Thus, calcium response to nAChR ligands in bone marrow PMNs depends on their maturity level.

Effect of Perfluorooctanesulfonic acid (PFOS) on immune cell development and function in mice.

Perfluoroctanesulfonate (PFOS) belongs to a larger family of compounds known as Per- and polyfluoroalkyl substances (PFAS). The strength of the carbon-fluorine bond makes PFOS extremely resistant to environmental degradation. Due to its persistent nature, research has been directed to elucidating possible health effects of PFOS on humans and laboratory animals. Here we have explored the effects of PFOS exposure on immune development and function in mice. We exposed adult mice to 3 and 1.5 µg/kg/day of PFOS for 2 and 4 weeks, respectively, and examined the effects of PFOS exposure on populations of T cells, B cells, and granulocytes. These doses of PFOS resulted in serum levels of approximately 100 ng/mL with no weight loss during exposure. We find that PFOS does not affect T-cell development during this time. However, while PFOS exposure reduced immune cell populations in some organs, it also led to an increase in the numbers of cells in others, suggesting possible relocalization of cells. We also examined the effect of PFOS on the response to influenza virus infection. We find that exposure to PFOS at 1.5 µg/kg/day of PFOS for 4 weeks does not affect weight loss or survival, nor is viral clearance affected. Analysis of antibody and T cell specific antiviral responses indicate that at this concentration, PFOS does not suppress the immune cell development or antigen specific immune response.

Pig-a gene mutations in bone marrow granulocytes of procarbazine-treated F344 rats.

It was previously demonstrated that procarbazine (PCZ) is positive in the rat erythrocyte Pig-a gene mutation assay. However, since mammalian erythrocytes lack genomic DNA, it was necessary to analyze nucleated bone-marrow erythroid precursor cells to confirm that PCZ induces mutations in the Pig-a gene (Revollo et al., Environ Mol Mutagen, 2020). In this study, the association between Pig-a mutation and loss of GPI anchors was further strengthened and the genesis of Pig-a mutation in PCZ-dosed rats was evaluated by analyzing bone-marrow granulocytes. Erythrocytes and granulocytes both originate from myeloid progenitor cells, but granulocytes contain DNA throughout their developmental stages. F344 rats were treated with three doses of 150 mg/kg PCZ; 2 weeks later, CD48-deficient mutant phenotype bone-marrow granulocytes (BMGs [CD11b+ ]) were isolated by flow-cytometric sorting. Sequencing data showed that the CD48-deficient mutant phenotype BMGs contained mutations in the Pig-a gene while wild-type BMGs did not. PCZ-induced mutations included missense, nonsense and splice site variants; the majority of mutations were A > T, A > C, and A > G, with the mutated A on the nontranscribed DNA strand. The PCZ-induced mutational analysis in BMGs supports the association between the phenotype measured in the Pig-a assay and mutation in the Pig-a gene. Also, PCZ mutation spectra were similar in bone-marrow erythroids and BMGs, but none of the mutations detected in BMGs were the same as the erythroid precursor cell mutations from the same rats. Thus, mutations induced in the Pig-a assay appear to be induced after commitment of myeloid progenitor cells to either the granulocyte or erythroid pathway.

HDN-1 induces cell differentiation toward apoptosis in promyelocytic leukemia cells depending on its selective effect on client proteins of Hsp90.

Heat Shock Protein 90 (Hsp90) is frequently upregulated in many cancers, and its inhibition simultaneously blocks multiple signaling pathways, resulting in cell differentiation or apoptosis. However, the complexity of Hsp90 in differentiation and its relation with apoptosis have remained unsettled. In this study, we demonstrated that HDN-1, a C-terminal inhibitor of Hsp90, induced the differentiation of HL-60 cells toward apoptosis. HDN-1 induced the differentiation of cells containing mutant AML1-ETO into mature granulocytes, which was related to its selective effect on client proteins of Hsp90. HDN-1 destabilized AML1-ETO and preserved C/EBPß at the same time, thereby induced a total increase in C/EBPß levels because of AML1-ETO negative regulation to C/EBPß expression. Neither HDN-1 nor 17-AAG (an N-terminal inhibitor of Hsp90) led to the differentiation of NB4 cells because mutant PML-RARα was not affected as a client protein of Hsp90; thus, no additional expression of C/EBPß was induced. 17-AAG did not affect the differentiation of HL-60 cells due to decreased AML1-ETO and C/EBPß levels. These results indicate that HDN-1 drives cell differentiation toward apoptosis depending on its selective influence on client proteins of Hsp90, establishing the relationship between differentiation and apoptosis and uncovering the mechanism of HDN-1 in promyelocytic leukemia cell differentiation. Moreover, HDN-1 is very promising for the development of anticancer agents with the induction of differentiation.

Frequency and perturbations of various peripheral blood cell populations before and after eculizumab treatment in paroxysmal nocturnal hemoglobinuria.

While red blood cells (RBCs) and granulocytes have been more studied, platelets and reticulocytes are not commonly used in paroxysmal nocturnal hemoglobinuria (PNH) flow-cytometry and less is known about susceptibility to complement-mediated destruction and effects of anti-complement therapy on these populations. We performed flow-cytometry of RBCs and granulocytes in 90 PNH patients and of platelets and reticulocytes in a subgroup (N = 36), to unveil perturbations of these populations during PNH disease course before and after anti-complement treatment. We found that platelets and reticulocytes were less sensitive to complement-mediated lysis than RBCs but not as resistant as granulocytes, as shown by mean sensitive fraction (difference in a given PNH population vs. PNH granulocyte clone size). In treated patients, reticulocytes, platelets, RBCs (with differences between type II and III) and granulocytes significantly increased post-treatment, confirming the role of PNH hematopoiesis within the context of anti-complement therapy. Moreover, we found that PNH platelet clone size reflects PNH granulocyte clone size. Finally, we established correlations between sensitive fraction of PNH cell-types and thrombosis. In sum, we applied a flow-cytometry panel for investigation of PNH peripheral blood populations' perturbations before and after eculizumab treatment to explore complement-sensitivity and kinetics of these cells during the disease course.

Diacetoxyscirpenol-induced heterophil extracellular traps contribute to the immune toxicity of liver injury in chickens.

Diacetoxyscirpenol (DAS) is one kind of type A trichothecene mycotoxin which produced by Fusarium species which contaminates agricultural crops and food. DAS attracts particular attention because of the strong toxicity. Heterophil extracellular traps (HETs) is a defense mechanism in the chicken innate immune. In this study, we firstly examine the effects and molecular mechanisms of DAS on HETs release, and then investigate the immune toxicity of DAS-induced HETs on chicken liver. HETs structures were observed by immunofluorescence staining and mechanisms were investigated by fluorescence microplate and Western blot. The results showed DAS triggered HETs formation which consists of chromatin decorated with citrullinated histone 3 (citH3) and elastase. Glycolysis was confirmed to be involved in this process and the inhibitors of NADPH oxidase, ERK1/2, p38 MAPK-signaling pathways and glycolysis significantly decreased HETs formation. Moreover, investigation in vivo showed DAS significantly increased HETs formation in serum and DNase I (a standard degradative agent of HETs) significantly decreased the ALT and AST levels and ameliorated DAS-caused inflammatory cell infiltration of liver. In conclusion, this study proves that DAS-induced HETs formation plays an immune toxicity role in chicken liver injury and these results provide a new therapeutic target for DAS-induced liver injury in chickens.

Pre-clinical evaluation of an innovative oral nano-formulation of baicalein for modulation of radiation responses.

There is an unmet medical need for non-toxic and effective radiation countermeasures for prevention of radiation toxicity during planned exposures. We have earlier shown that intraperitoneal administration of baicalein (BCL) offers significant survival benefit in animal model. Safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of baicalein has been reported in pre-clinical model systems and also in healthy human volunteers. However, clinical translation of baicalein is hindered owing to poor bioavailability due to lipophilicity. In view of this, we fabricated and characterized in-situ solid lipid nanoparticles of baicalein (SLNB) with effective drug entrapment and release kinetics. SLNB offered significant protection to murine splenic lymphocytes against 4 Gy ionizing radiation (IR) induced apoptosis. Oral administration of SLNB exhibited ~70% protection to mice against whole body irradiation (WBI 7.5 Gy) induced mortality. Oral relative bioavailability of BCL was enhanced by over ~300% after entrapment in the SLNB as compared to BCL. Oral dosing of SLNB resulted in transient increase in neutrophil abundance in peripheral blood. Interestingly, we observed that treatment of human lung cancer cells (A549) with radioprotective dose of SLNB exhibited radio-sensitization as evinced by decrease in survival and clonogenic potential. Contrary to antioxidant nature of baicalein in normal cells, SLNB treatment induced significant increase in cellular ROS levels in A549 cells probably due to higher uptake and inhibition of TrxR. Thus, a pharmaceutically acceptable SLNB exhibited improved bioavailability, better radioprotection to normal cells and sensitized cancer cells to radiation induced killing as compared to BCL suggesting its possible utility as an adjuvant during cancer radiotherapy.

EFFICIENCY OF BONE MARROW PRECURSOR CELL COLONY-FORMING AS A PREDICTOR OF DISEASE COURSE IN PLASMA CELL MYELOMA PATIENTS WITH A HISTORY OF RADIATION EXPOSURE. / EFEKTYVNIST' KOLONIIeUTVORENNIa KLITYN-POPEREDNYKIV KISTKOVOGO MOZKU, IaK PROGNOSTYChNYI FAKTOR PEREBIGU PLAZMOKLITYNNOÏ MIIeLOMY U OSIB Z RADIATsIINYM ANAMNEZOM.

OBJECTIVE: Assessment of role of the bone marrow colony-forming efficiency in plasma cell myeloma patients at different stages of treatment as a prognostic criterion for the disease course. MATERIALS AND METHODS: The colony forming efficiency (CFE) was assayed in stage I-II plasma cell myeloma (PCM)patients (n = 37) aged 42-73, namely in patients survived after the Chornobyl NPP accident (n = 21) and persons notexposed to ionizing radiation (n = 16). There were 11 males exposed to ionizing radiation and having got stage I PCM,9 males and 3 females exposed and having got stage II PCM, 3 males and 3 females not exposed and having got stageI PCM, 6 males and 2 females not exposed and having got stage II PCM. Healthy persons (n = 20) were included in thecontrol group. RESULTS: Number of the bone marrow (BM) granulocyte-macrophage colony-forming units (CFU-GM) in both exposedand not exposed PCM patients depended on a disease stage. CFU-GM was (16.7 ± 1.2) in the stage I PCM patients vs.(11.1 ± 1.1) in the stage II PCM ones both being lower (p < 0.05) compared to control (64.5 ± 2.2). Changes in cluster formation were similar, i.e. (37.7 ± 1.6) and (19.4 ± 1.3) correspondingly in the stage I and stage II PCM patients.Respective values in control were (89.8 ± 3.6). The CFE in stage I and stage II PCM patients at the time of diagnosiswas lower (5.7 ± 1.5 and 2.4 ± 1.1 respectively) vs. control (39.5 ± 1.51, p < 0.05), but has increased in remission upto (29. 6 ± 1.8) and (13.8 ± 1.2) respectively. There was no difference at that between the irradiated and non-irradiated patients. Number of the fibroblast colony-forming units (CFU-F) in the stage I and stage II PCM patients duringdiagnosis, namely (43.9 ± 5.4) and (22.5 ± 3.7), was lower (p < 0.05) vs. control (110.5 ± 4.9). Upon reaching remission the CFU-F value increased significantly (p < 0.05), reaching (87.4 ± 4.2) and (55.6 ± 2.7) correspondingly in thestage I and stage II PCM patients. CONCLUSION: Dependence of the BM cell CFE on the stage of PCM and presence or absence of remission was established. Prognostic value of the CFE of BM CFU-GM in terms of life span of patients was shown (Ro Spearm = 0.39,p < 0.02), namely in case of CFE > 20 before the polychemotherapy administration the life span of PCM patients wassignificantly longer vs. cases of CFE < 20.

Inhibitory Effects of Green Asparagus Extract, Especially Phospholipids, on Allergic Responses in Vitro and in Vivo.

Asparagus (Asparagus officinalis L.) is one of the widely consumed vegetables. To investigate the mechanism underlying the anti-allergic responses of asparagus, we extracted different fractions from asparagus and measured their inhibitory effects on ß-hexosaminidase release in RBL-2H3 cells in vitro and an atopic dermatitis NC/Nga mouse model in vivo. The lipid fractions from asparagus were extracted with 50% ethanol, separated using chloroform by liquid-liquid phase separation, and fractionated by solid-phase extraction. Among them, acetone fraction (rich in glycolipid) and MeOH fraction (rich in phospholipid) markedly inhibited ß-hexosaminidase release from RBL-2H3 cells. In NC/Nga mice treated with picryl chloride, atopic dermatitis was alleviated following exposure to the 50% EtOH extract, acetone fraction, and methanol fraction. The inhibitory effects of asparagus fractions in vivo were supported by the significant decrease in serum immunoglobulin E (IgE) levels. The phospholipid fractions showed significantly better inhibitory effects, and phosphatidic acid from this fraction showed the best inhibitory effect on ß-hexosaminidase release. In mice challenged with ovalbumin (OVA), oral administration of asparagus extract and its fractions decreased the OVA-specific IgE level and total IgE, indicating that these effects may be partly mediated through the downregulation of antigen-specific IgE production. Taken together, the present study shows for the first time that asparagus extract and its lipid fractions could potentially mitigate allergic reactions by decreasing degranulation in granulocytes. Our study provides useful information to develop nutraceuticals and functional foods fortified with asparagus.

Design of novel granulopoietic proteins by topological rescaffolding.

Computational protein design is rapidly becoming more powerful, and improving the accuracy of computational methods would greatly streamline protein engineering by eliminating the need for empirical optimization in the laboratory. In this work, we set out to design novel granulopoietic agents using a rescaffolding strategy with the goal of achieving simpler and more stable proteins. All of the 4 experimentally tested designs were folded, monomeric, and stable, while the 2 determined structures agreed with the design models within less than 2.5 Å. Despite the lack of significant topological or sequence similarity to their natural granulopoietic counterpart, 2 designs bound to the granulocyte colony-stimulating factor (G-CSF) receptor and exhibited potent, but delayed, in vitro proliferative activity in a G-CSF-dependent cell line. Interestingly, the designs also induced proliferation and differentiation of primary human hematopoietic stem cells into mature granulocytes, highlighting the utility of our approach to develop highly active therapeutic leads purely based on computational design.