Reduction of c-Fos via Overexpression of miR-34a Results in Enhancement of TNF- Production by LPS in Neutrophils from Myelodysplastic Syndrome Patients

Although increased TNF-α has been considered to cause ineffective hematopoiesis in myelodysplastic syndromes (MDS), the mechanisms of TNF-α elevation are not known. We recently found that c-Fos mRNA stabilization under translation-inhibiting stimuli was impaired in MDS-derived neutrophilic granulocytes. In the current study, we identified overexpression of c-Fos-targeting miR-34a and miR-155 as the cause of impairment. Expression levels of miR-34a but not miR-155 inversely correlated with ratios of c-Fos-positive cells in MDS-derived CD16⁺ neutrophils (r = -0.618, P<0.05), which were analyzed by flow cytometry. Among the seventeen patients, c-Fos was detectable in less than 60% of CD16⁺ cells in eight patients (Group A), while five (Group B) expressed c-Fos in more than 80% of CD16⁺ cells, which was consistent with the controls (88.6 ± 7.8%). Group A-derived granulocytes secreted more TNF-α in response to 1 μM LPS for 3 hours (735.4 ± 237.5 pg/mL) than Group B (143.5 ± 65.7 pg/mL, P<0.05) and healthy controls (150.8 ± 91.5 pg/mL, P<0.05). Knockdown of c-Fos in neutrophil-like differentiated HL60 increased the binding of NF-κB p65 to the promoter region of TNF-α DNA. Thus, c-Fos reduction via overexpression of miR-34a contributes to TNF-α overproduction under inflammatory stimuli in MDS.

Alterations in nuclear structure promote lupus autoimmunity in a mouse model

Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by the development of autoantibodies that recognize components of the cell nucleus. The vast majority of lupus research has focused on either the contributions of immune cell dysfunction or the genetics of the disease. Because granulocytes isolated from human SLE patients had alterations in neutrophil nuclear morphology that resembled the Pelger-Huet anomaly, and had prominent mis-splicing of mRNA encoding the nuclear membrane protein lamin B receptor (LBR), consistent with their Pelger-Huet-like nuclear morphology, we used a novel mouse model system to test the hypothesis that a disruption in the structure of the nucleus itself also contributes to the development of lupus autoimmunity. The lupus-prone mouse strain New Zealand White (NZW) was crossed with c57Bl/6 mice harboring a heterozygous autosomal dominant mutation in Lbr (B6.Lbr(ic/+)), and the (NZW×B6.Lbr(ic))F1 offspring were evaluated for induction of lupus autoimmunity. Only female (NZW×B6.Lbr(ic))F1 mice developed lupus autoimmunity, which included splenomegaly, kidney damage and autoantibodies. Kidney damage was accompanied by immune complex deposition, and perivascular and tubule infiltration of mononuclear cells. The titers of anti-chromatin antibodies exceeded those of aged female MRL-Fas(lpr) mice, and were predominantly of the IgG2 subclasses. The anti-nuclear antibody staining profile of female (NZW×B6.Lbr(ic))F1 sera was complex, and consisted of an anti-nuclear membrane reactivity that colocalized with the A-type lamina, in combination with a homogeneous pattern that was related to the recognition of histones with covalent modifications that are associated with gene activation. An anti-neutrophil IgM recognizing calreticulin, but not myeloperoxidase (MPO) or proteinase 3 (PR3), was also identified. Thus, alterations in nuclear structure contribute to lupus autoimmunity when expressed in the context of a lupus-prone genetic background, suggesting a mechanism for the development of lupus autoimmunity in genetically predisposed individuals that is induced by the disruption of nuclear architecture.

[The dynamics of paroxysmal nocturnal hemoglobinuria clone in patients with aplastic anemia in process of immune suppressive therapy]

The implementation of principles of highly sensitive flow cytometry into diagnostic of paroxysmal nocturnal hemoglobinuria increased rate of detection of paroxysmal nocturnal hemoglobinuria clone in patients with aplastic anemia already at early stages of diagnosis establishment (up to 79%). However, detection of paroxysmal nocturnal hemoglobinuria clone attracts interest not only from point of view of progression in % of patients with aplastic anemia). The occurrence of paroxysmal nocturnal hemoglobinuria clone in patients with aplastic anemia can be accompanied by hidden disorders of haemopoesis with increasing risk in conditions of proliferative stress. Hence, it is necessary to monitor the given clone during all period of observation. The study is a prospective investigation analyzing dynamics of paroxysmal nocturnal hemoglobinuria clone in process of immune suppressive therapy applied to 44 patients with aplastic anemia. The mentioned clone was initially detected in 59.6% of patients. The median of observation amounted to 27 (9-48) months. Depending on size of granulocytic paroxysmal nocturnal hemoglobinuria clone patients were allocated in four conditional groups: group I - from 0.01% to 0.99% (n=11); group II - from 1% to 9.99% (n=8); group III - from10% to 49.9% (n=4); group IV - from 50% and more (n=5). In the course of study the differently directed dynamics of paroxysmal nocturnal hemoglobinuria clone was revealed. In 3 out of 11 patients from group I median of paroxysmal nocturnal hemoglobinuria clone increased from minor values (less than 1%) to 3.55%; at that in one patient occurred total elimination of paroxysmal nocturnal hemoglobinuria clone to 12th month of observation. The noticeable unidirectional dynamics was established in patients of group III: already to 3d month of observation, simultaneously with becoming of remission, median of size of paroxysmal nocturnal hemoglobinuria clone in group diminished from 22.9% (18.39%-24.77%) to 5.6% (1.5%-6.7%). Among patients of groups II and IV paroxysmal nocturnal hemoglobinuria clone remained stable. The development of hemolytic form of paroxysmal nocturnal hemoglobinuria was observed in all patients of group IV i.e. in 18% of patients with aplastic anemia with primarily detected paroxysmal nocturnal hemoglobinuria clone. In the process of observation, in 37% of patients with aplastic anemia without primarily detected paroxysmal nocturnal hemoglobinuria clone its occurrence and persistence (median - 0.34% (0.1%-6.2%)) was noticed. According to the results of study, alteration of sizes of paroxysmal nocturnal hemoglobinuria clone or its occurrence develop in case of response to ISP and, most probably, depend on advantage of growth in the process of repair of normal (GPI positive) or clonal (GPI negative) hemopoiesis. To acquire more reliable conclusions will be possible through development of techniques of molecular diagnostic simultaneously with dynamic observation of course of disease in the given patients.

Mesenchymal Stem Cells (MSC) Regulate Activation of Granulocyte-Like Myeloid Derived Suppressor Cells (G-MDSC) in Chronic Myeloid Leukemia Patients

It is well known that mesenchymal stem cells (MSC) have a role in promotion of tumor growth, survival and drug-resistance in chronic myeloid leukemia (CML). Recent reports indicated that a subpopulation of myeloid cells, defined as granulocyte-like myeloid-derived suppressor cells (G-MDSC) is increased in these patients. So far, the role of MSC in MDSC expansion and activation into the BM microenvironment remains unexplored. To address this question, here we use a specific experimental model in vitro, co-culturing MSC with peripheral blood mononucleated cells (PBMC) from normal individuals, in order to generate MSC-educated G-MDSC. Although MSC of healthy donors (HD) and CML patients were able to generate the same amount of MDSC, only CML-MSC-educated G-MDSC exhibited suppressive ability on autologous T lymphocytes. In addition, compared with HD-MSC, CML-MSC over-expressed some immunomodulatory factors including TGFβ, IL6 and IL10, that could be involved in MDSC activation. CML-MSC-educated G-MDSC expressed higher levels of ARG1, TNFα, IL1β, COX2 and IL6 than G-MDSC isolated from co-culture with HD-MSC. Our data provide evidence that CML-MSC may play a critical role in tumor microenvironment by orchestrating G-MDSC activation and regulating T lymphocytes-mediated leukemia surveillance, thus contributing to CML immune escape.

Hepatic Alveolar Echinococcosis in Cynomolgus Monkeys (Macaca fascicularis)

Alveolar echinococcosis was diagnosed in 12 cynomolgus monkeys ( Macaca fascicularis) at postmortem examination within a period of 6 years. Besides consistent involvement of the liver, parasitic lesions were also present in mesenteric lymph nodes, pancreas, lung, and kidney. In the liver, various patterns of host's responses to parasitic tissue could be distinguished. Infiltration of macrophages, often multinucleated, around usually intact metacestodes was the main feature of one pattern. A second pattern was characterized by the presence of abundant, normally degenerate granulocytes in addition to macrophages surrounding collapsed laminated structures. Finally and as a third pattern, some cysts were surrounded by marked collagen deposition, which was usually not a significant feature of the other foci. Parasitic cysts with protoscolices were observed in foci with the first and third pattern but not in the second one. The simultaneous occurrence of all three patterns was observed in most animals. Type AA amyloid was identified either in the space of Dissé, macro-phages or blood vessel walls in nine animals using immunohistochemistry. Identity of parasitic structures such as metacestodes of Echinococcus multilocularis was confirmed immunohistochemically. All animals that could be tested serologically (7/12) had detectable antibodies against the E. multilocularis-specific Em2 antigen. Liver lesions of six animals were additionally analyzed by polymerase chain reaction, yielding the amplification of a specific E. multilocularis DNA fragment in each case.

Low-Density Granulocytes Are Elevated in Mycobacterial Infection and Associated with the Severity of Tuberculosis

Tuberculosis remains a global health problem caused by infection with Mycobacterium tuberculosis. Numerous studies have established a close correlation between the development of tuberculosis and the roles of neutrophils. Recently, a distinct population of CD15+ granulocytes was found to be present in the peripheral blood mononuclear cell (PBMC) fraction in humans. This population of granulocytes, termed low-density granulocytes (LDGs), was reported to be elevated and associated with disease activity or severity in a number of different conditions including SLE, asthma and HIV infection. However, both the frequency and clinical significance of LDGs associated with tuberculosis are unclear. Here we determined LDG levels and made comparisons between subjects with active pulmonary tuberculosis (PTB) and healthy controls, between PTB patients with mild-to-moderate disease and patients with advanced disease, and among PTB patients following anti-tuberculous therapy of varying durations. The direct correlation between M. tuberculosis infection and LDG levels was confirmed by in vitro infection of whole peripheral blood and isolated granulocytes with mycobacteria. Our results demonstrated that PBMCs in PTB patients contained significantly elevated percentages of LDGs compared with control subjects. LDGs in tuberculosis expressed higher levels of activation markers compared to normal-density granulocytes (NDGs). M. tuberculosis induced the generation of LDGs in both whole blood and isolated NDGs from control subjects, which suggests that LDGs associated with M. tuberculosis infection are likely to originate from in situ activation. Furthermore, our results revealed that the frequency of LDGs is associated with the severity of tuberculosis.

Integration of Immature Granulocytes Quantification With the Version 2.0 UniCel DxH 800 in the HematoFlow Strategy

OBJECTIVES

Our aim was to define whether the early granulocyte cell marker (EGC%_DxH) parameter might replace immature granulocytes counts obtained by HematoFlow (IG%_HF) and/or manual differential count (IG%_manual).

METHODS

We conducted a study over a 10-day period in February 2014 whereby 402 samples were analyzed for the IG flag. We correlated the EGC%_DxH vs IG%_HF and IG%_manual, identified any discrepant results and finally looked at the impact on our workflow by incorporation of the EGC% into our WBC differential algorithm.

RESULTS

On an initial training set, a receiver operating characteristic (ROC) curve analysis showed a threshold of 0.9% for EGC%_DxH (sensitivity of 91.7%, specificity of 93.5% and an area under the curve of 0.965). Further analysis of the dataset (259 samples) found a correlation of the EGC%_DxH to all our IG% counting methods (r = 0.963). Incorporation of the EGC%_DxH into the WBC HematoFlow differential resulted in a 36% reduction of samples requiring HematoFlow and/or slide review.

CONCLUSIONS

The EGC% generated by the DxH 800 can be easily incorporated into existing HematoFlow and slide review algorithms.

[Tumor-associated eosinophilia]

The review provides information on current literature on structural and functional features of eosinophilic granulocytes and their role in the pathogenesis of cancer. There are examined data of clinical and experimental studies about an influence of hemic and tissue eosinophilia on the course and prognosis of malignant tumors. Molecular mechanisms of action of eosinophils in tumor pathology are discussed.

[EPIDEMIOLOGIC ASPECTS OF HUMAN GRANULOCYTIC ANAPLASMOSIS IN THE WESTERN REGION OF UKRAINE]

This article presents data of complex study of human granulocytic anaplasmosis the human granulocytic anaplasmosis (HGA) in the western region of Ukraine. Natural HGA foci were identified, where the prevalence of A. phagocytophilum in the main vector (I. ricinus) amount to (12.0 +/- 0.7) %, and seroprevalence of HGA among the healthy population--(28.6 +/- 1.6) %. It's shown that A. phagocytophilum is the etiologic agent of (33.7 +/- 4.9) % of undiagnosed cases of seasonal febrile diseases. Principal characteristics of HGA epidemiology: spring-summer scasonality, the prevalence of disease in the age structure of people of active age (45.30 +/- 1.95 years), a significant level combination with (60.4 +/- 2.2) % Lyme-horreliosis and other tick-borne infections (mixed infections), the different level of activity of HGA epidemic process in forest and steppe geographical landscape zones--were revealed.

Frequencies, Laboratory Features, and Granulocyte Activation in Chinese Patients with CALR-Mutated Myeloproliferative Neoplasms

Somatic mutations in the CALR gene have been recently identified as acquired alterations in myeloproliferative neoplasms (MPNs). In this study, we evaluated mutation frequencies, laboratory features, and granulocyte activation in Chinese patients with MPNs. A combination of qualitative allele-specific polymerase chain reaction and Sanger sequencing was used to detect three driver mutations (i.e., CALR, JAK2V617F, and MPL). CALR mutations were identified in 8.4% of cases with essential thrombocythemia (ET) and 5.3% of cases with primary myelofibrosis (PMF). Moreover, 25% of polycythemia vera, 29.5% of ET, and 48.1% of PMF were negative for all three mutations (JAK2V617F, MPL, and CALR). Compared with those patients with JAK2V617F mutation, CALR-mutated ET patients displayed unique hematological phenotypes, including higher platelet counts, and lower leukocyte counts and hemoglobin levels. Significant differences were not found between Chinese PMF patients with mutants CALR and JAK2V617F in terms of laboratory features. Interestingly, patients with CALR mutations showed markedly decreased levels of leukocyte alkaline phosphatase (LAP) expression, whereas those with JAK2V617F mutation presented with elevated levels. Overall, a lower mutant rate of CALR gene and a higher triple-negative rate were identified in the cohort of Chinese patients with MPNs. This result indicates that an undiscovered mutant gene may have a significant role in these patients. Moreover, these pathological features further imply that the disease biology varies considerably between mutants CALR and JAK2V617F.

Induction of autophagy is a key component of all-trans-retinoic acid-induced differentiation in leukemia cells and a potential target for pharmacologic modulation

Acute myeloid leukemia (AML) is characterized by the accumulation of immature blood cell precursors in the bone marrow. Pharmacologically overcoming the differentiation block in this condition is an attractive therapeutic avenue, which has achieved success only in a subtype of AML, acute promyelocytic leukemia (APL). Attempts to emulate this success in other AML subtypes have thus far been unsuccessful. Autophagy is a conserved protein degradation pathway with important roles in mammalian cell differentiation, particularly within the hematopoietic system. In the study described here, we investigated the functional importance of autophagy in APL cell differentiation. We found that autophagy is increased during all-trans-retinoic acid (ATRA)-induced granulocytic differentiation of the APL cell line NB4 and that this is associated with increased expression of LC3II and GATE-16 proteins involved in autophagosome formation. Autophagy inhibition, using either drugs (chloroquine/3-methyladenine) or short-hairpin RNA targeting the essential autophagy gene ATG7, attenuates myeloid differentiation. Importantly, we found that enhancing autophagy promotes ATRA-induced granulocytic differentiation of an ATRA-resistant derivative of the non-APL AML HL60 cell line (HL60-Diff-R). These data support the development of strategies to stimulate autophagy as a novel approach to promote differentiation in AML.

RORC1 Regulates Tumor-Promoting "Emergency" Granulo-Monocytopoiesis

Cancer-driven granulo-monocytopoiesis stimulates expansion of tumor promoting myeloid populations, mostly myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). We identified subsets of MDSCs and TAMs based on the expression of retinoic-acid-related orphan receptor (RORC1/RORγ) in human and mouse tumor bearers. RORC1 orchestrates myelopoiesis by suppressing negative (Socs3 and Bcl3) and promoting positive (C/EBPβ) regulators of granulopoiesis, as well as the key transcriptional mediators of myeloid progenitor commitment and differentiation to the monocytic/macrophage lineage (IRF8 and PU.1). RORC1 supported tumor-promoting innate immunity by protecting MDSCs from apoptosis, mediating TAM differentiation and M2 polarization, and limiting tumor infiltration by mature neutrophils. Accordingly, ablation of RORC1 in the hematopoietic compartment prevented cancer-driven myelopoiesis, resulting in inhibition of tumor growth and metastasis.

Interferon at the crossroads of allergy and viral infections

IFN-α/β was first described as a potent inhibitor of viral replication, but it is now appreciated that IFN signaling plays a pleiotropic role in regulating peripheral T cell functions. Recently, IFN-α/β was shown to block human Th2 development by suppressing the transcription factor GATA3. This effect is consistent with the role for IFN-α/β in suppressing allergic inflammatory processes by blocking granulocyte activation and IL-4-mediated B cell isotype switching to IgE. With the consideration of recent studies demonstrating a defect in IFN-α/β secretion in DCs and epithelial cells from individuals with severe atopic diseases, there is an apparent reciprocal negative regulatory loop in atopic individuals, whereby the lack of IFN-α/β secretion by innate cells contributes to the development of allergic Th2 cells. Is it possible to overcome these events by treating with IFN-α/β or by inducing its secretion in vivo? In support of this approach, case studies have documented the therapeutic potential of IFN-α/β in treating steroid-resistant allergic asthma and other atopic diseases. Additionally, individuals with asthma who are infected with HCV and respond to IFN therapy showed a reduction in symptoms and severity of asthma attacks. These findings support a model, whereby allergic and antiviral responses are able to cross-regulate each other, as IgER cross-linking of pDCs prevents IFN-α/β production in response to viral infection. The clinical importance of upper-respiratory viruses in the context of allergic asthma supports the need to understand how these pathways intersect and to identify potential therapeutic targets.

Live imaging of transgenic mice expressing FRET biosensors

In recent years, fluorescence imaging has received particular attention, due to increasing availabilities of fluorescent proteins and dyes, which had driven the development of novel biosensors. Genetically-encoded biosensors based on the principle of Förster resonance energy transfer (FRET) have been widely used in biology to visualize the spatiotemporal dynamics of signaling molecules. Despite the increasing multitude of these biosensors, their application has been mostly limited to cultured cells with transient biosensor expression, due to difficulties in stable expression of FRET biosensors. In this study, we report efficient generation of transgenic mouse lines expressing heritable and functional biosensors for ERK and PKA. These transgenic mice were generated by the cytoplasmic co-injection of Tol2 transposase mRNA and a circular plasmid harboring Tol2 recombination sites. Observation of these transgenic mice by two-photon excitation microscopy yielded real-time activity maps of ERK and PKA in various tissues, with greatly improved signal-to-background ratios. Our transgenic mice may be bred into diverse genetic backgrounds; moreover, the protocol we have developed paves the way for the generation of transgenic mice that express other FRET biosensors, with important applications in the characterization of physiological and pathological signal transduction events in addition to drug development and screening.

Human TM9SF4 Is a New Gene Down-Regulated by Hypoxia and Involved in Cell Adhesion of Leukemic Cells

Background

The transmembrane 9 superfamily protein member 4, TM9SF4, belongs to the TM9SF family of proteins highly conserved through evolution. TM9SF4 homologs, previously identified in many different species, were mainly involved in cellular adhesion, innate immunity and phagocytosis. In human, the function and biological significance of TM9SF4 are currently under investigation. However, TM9SF4 was found overexpressed in human metastatic melanoma and in a small subset of acute myeloid leukemia (AMLs) and myelodysplastic syndromes, consistent with an oncogenic function of this gene.

Purpose and Results

In this study, we first analyzed the expression and regulation of TM9SF4 in normal and leukemic cells and identified TM9SF4 as a gene highly expressed in human quiescent CD34⁺ hematopoietic progenitor cells (HPCs), regulated during monocytic and granulocytic differentiation of HPCs, both lineages giving rise to mature myeloid cells involved in adhesion, phagocytosis and immunity. Then, we found that TM9SF4 is markedly overexpressed in leukemic cells and in AMLs, particularly in M2, M3 and M4 AMLs (i.e., in AMLs characterized by the presence of a more or less differentiated granulocytic progeny), as compared to normal CD34⁺ HPCs. Proliferation and differentiation of HPCs occurs in hypoxia, a physiological condition in bone marrow, but also a crucial component of cancer microenvironment. Here, we investigated the impact of hypoxia on TM9SF4 expression in leukemic cells and identified TM9SF4 as a direct target of HIF-1α, downregulated in these cells by hypoxia. Then, we found that the hypoxia-mediated downregulation of TM9SF4 expression is associated with a decrease of cell adhesion of leukemic cells to fibronectin, thus demonstrating that human TM9SF4 is a new molecule involved in leukemic cell adhesion.

Conclusions

Altogether, our study reports for the first time the expression of TM9SF4 at the level of normal and leukemic hematopoietic cells and its marked expression at the level of AMLs displaying granulocytic differentiation.

Growth and responsiveness of human granulocytic leukemic cells in vitro

Cells from patients with acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) can be grown and their properties analyzed in agar gel cultures. Levels of the glycoprotein regulator colony stimulating factor (CSF) were found to be elevated in 19-66% of plasmas tested from patients with various types of granulocytic leukemia, and the growth of AML and CML cells in vitro was observed to be dependent on, and responsive to, stimulation by CSF-containing material. In both diseases, the leukemic cells appear to be in a responsive state with respect to normal growth regulators, and potentially alterations in regulator levels may therefore be able to achieve sustained arrest of the growth of leukemic populations.

Granulocytic myeloid derived suppressor cells expansion during active pulmonary tuberculosis is associated with high nitric oxide plasma level

Tuberculosis (TB) is still the principal cause of death caused by a single infectious agent, and the balance between the bacillus and host defense mechanisms reflects the different manifestations of the pathology. The aim of this work was to study the role of myeloid-derived suppressor cells (MDSCs) during active pulmonary tuberculosis at the site of infection. We observed an expansion of MDSCs in the lung and blood of patients with active TB, which are correlated with an enhanced amount of nitric oxide in the plasma. We also found that these cells have the remarkable ability to suppress T-cell response, suggesting an important role in the modulation of the immune response against TB. Interestingly, a trend in the diminution of MDSCs was found after an efficacious anti-TB therapy, suggesting that these cells may be used as a potential biomarker for monitoring anti-TB therapy efficacy.

[REARRANGEMENT OF THE LYMPH TISSUE IN THE MICE SPLEEN AND JEJUNUM WALL DURING THE GROUND-BASED REPRODUCTION OF THE CONDITIONS OF ANIMAL MAINTENANCE IN THE BIOSATTELITE BION-M1 MISSION]

Purpose of the investigation was microscopic examination of changes in cyto architectonics of the spleen and jejunum lymph (immune) tissue in 19-20-week C57BL/6N male mice exposed to some conditions their counterparts had lived in during the 30-d Bion-M1 mission (ground experiment). Local deviations in reactions of the morphofunctional zones of these organs were found. In the spleen, reaction in the centers of lymph nodules generation or the B-lymphocytes maturation zone grows strong. Changes in the cell composition of periarterial lymph sheaths that constitute the morphological site of T-lymphocytes accumulation suggest inhibition of its functional activity. Cell composition of the jejunum wall structure implies a decline of the jejunal immune activity. Our investigation of the organs taken from the ground control mice maintained in the flight BIOS-MLZh module evidences that unceasing noise, hypokinesia, isolation, and paste-like feed weaken general immunity of laboratory animals.

[Mesenchymal stem cells influence on leukocytes allergen-specific reactions in case of atopic hypersencitivity]

Buffy coat samples containing lymphocytes, monocytes and granulocytes, were obtained from the peripheral blood of 16 donors who had clinical manifestations of atopic hypersensitivity in their medical background. After ex vivo incubation with donor-specific allergens, the percentage of B- and T-lymphocytes and natural killers (NK) remained unchanged. Buffy coat incubation with allergens induced production of IgE and IL-4 in all studied samples. In 13 out of 16 cases the reaction to contact with an allergen was also evident in the increasing of T-activated lymphocytes (CD3+, HLA-DR+) subpopulation. Co-cultivation with MSC from bone marrow, adipose tissue and umbilical cord resulted in blocking of allergen-induced IgE and IL4 secretion and HLA-DR+ T-lymphocytes subpopulation increase. There were no significant differences in the effect of MSCs, isolated from three different sources, on allergen-specific responses of leukocytes. Co-culturing of leukocytes with MSCs from all three sources led to an increase in the content of regulatory T-lymphocytes by an average of 30%. Thus, the immunomodulatory activity of MSCs in vitro results in blocking of the effector part of allergic reactions.

[STRUCTURAL-FUNCTIONAL STATUS OF THE LYMPH TISSUE OF MICE LYMPHATIC NODES FOLLOWING THE 30-DAY FLIGHT ONBOARD SPACECRAFT BION-M1]

The article reports the results of studying the lymph tissue of mesenteric and cervical lymphatic nodes in C57BL/6N mice after the 30-day orbital flight onboard biosatellite Bion-M1. Histological and morphometric investigations revealed changes in the ratio of the nodes structural-functional zones and microstructure. Reductions in reticular cells, plasmocytes, macrophages and blasts in the nodes point to degradation of both humoral and cellular immunity.

Granulocytes impose a tight bottleneck upon the gut luminal pathogen population during Salmonella typhimurium colitis

Topological, chemical and immunological barriers are thought to limit infection by enteropathogenic bacteria. However, in many cases these barriers and their consequences for the infection process remain incompletely understood. Here, we employed a mouse model for Salmonella colitis and a mixed inoculum approach to identify barriers limiting the gut luminal pathogen population. Mice were infected via the oral route with wild type S. Typhimurium (S. Tm) and/or mixtures of phenotypically identical but differentially tagged S. Tm strains ("WITS", wild-type isogenic tagged strains), which can be individually tracked by quantitative real-time PCR. WITS dilution experiments identified a substantial loss in tag/genetic diversity within the gut luminal S. Tm population by days 2-4 post infection. The diversity-loss was not attributable to overgrowth by S. Tm mutants, but required inflammation, Gr-1+ cells (mainly neutrophilic granulocytes) and most likely NADPH-oxidase-mediated defense, but not iNOS. Mathematical modelling indicated that inflammation inflicts a bottleneck transiently restricting the gut luminal S. Tm population to approximately 6000 cells and plating experiments verified a transient, inflammation- and Gr-1+ cell-dependent dip in the gut luminal S. Tm population at day 2 post infection. We conclude that granulocytes, an important clinical hallmark of S. Tm-induced inflammation, impose a drastic bottleneck upon the pathogen population. This extends the current view of inflammation-fuelled gut-luminal Salmonella growth by establishing the host response in the intestinal lumen as a double-edged sword, fostering and diminishing colonization in a dynamic equilibrium. Our work identifies a potent immune defense against gut infection and reveals a potential Achilles' heel of the infection process which might be targeted for therapy.

Human organic cation transporter 1 protein levels of granulocytes can optimize imatinib therapy in patients with chronic myeloid leukemia

The human organic cation transporter 1 (hOCT1) is the major active influx protein responsible for the transport of imatinib mesylate (IM) into cells. Previous studies have used (14)C-labeled IM to demonstrate a link between chronic myeloid leukemia (CML) molecular response and hOCT1 activity. However, this method is not convenient in routine clinical practice. Hence, we detected hOCT1 protein expression levels (Choct1) of peripheral blood in CML patients and evaluated the relationship between Choct1 and IM response. A total of 83 patients who were diagnosed with Philadelphia chromosome (Ph)-positive CML with IM therapy and 31 heathy donors were collected. Choct1 were detected by indirect immunofluorescent flow cytometry. The study showed that Choct1 expression was higher in healthy donors than in CML patients (n = 31, 9.11 ± 6.04; n = 35, 5.60 ± 3.74; p = 0.005). Both Choct1 and plasma IM trough concentration (Cmin, n = 83) were significantly higher in patients with major molecular response (MMR) than those without (p = 0.011; p = 0.001, respectively), and patients with Choct1 ≥4.745 and Cmin ≥1,385 ng/ml were more likely to achieve MMR. hOCT1 expression levels measured using flow cytometry is a convenient and clinically available technique. The hOCT1 expression level can be an important predictor in CML patients treated with IM.

Giardia duodenalis infection reduces granulocyte infiltration in an in vivo model of bacterial toxin-induced colitis and attenuates inflammation in human intestinal tissue

Giardia duodenalis (syn. G. intestinalis, G. lamblia) is a predominant cause of waterborne diarrheal disease that may lead to post-infectious functional gastrointestinal disorders. Although Giardia-infected individuals could carry as much as 10⁶ trophozoites per centimetre of gut, their intestinal mucosa is devoid of overt signs of inflammation. Recent studies have shown that in endemic countries where bacterial infectious diseases are common, Giardia infections can protect against the development of diarrheal disease and fever. Conversely, separate observations have indicated Giardia infections may enhance the severity of diarrheal disease from a co-infecting pathogen. Polymorphonuclear leukocytes or neutrophils (PMNs) are granulocytic, innate immune cells characteristic of acute intestinal inflammatory responses against bacterial pathogens that contribute to the development of diarrheal disease following recruitment into intestinal tissues. Giardia cathepsin B cysteine proteases have been shown to attenuate PMN chemotaxis towards IL-8/CXCL8, suggesting Giardia targets PMN accumulation. However, the ability of Giardia infections to attenuate PMN accumulation in vivo and how in turn this effect may alter the host inflammatory response in the intestine has yet to be demonstrated. Herein, we report that Giardia infection attenuates granulocyte tissue infiltration induced by intra-rectal instillation of Clostridium difficile toxin A and B in an isolate-dependent manner. This attenuation of granulocyte infiltration into colonic tissues paralled decreased expression of several cytokines associated with the recruitment of PMNs. Giardia trophozoite isolates that attenuated granulocyte infiltration in vivo also decreased protein expression of cytokines released from inflamed mucosal biopsy tissues collected from patients with active Crohn’s disease, including several cytokines associated with PMN recruitment. These results demonstrate for the first time that certain Giardia infections may attenuate PMN accumulation by decreasing the expression of the mediators responsible for their recruitment.

Alterations in neutrophil production and function at an early stage in the high-fructose rat model of metabolic syndrome

BACKGROUND

Although neutrophils are crucially involved in inflammation, they have received only little attention in metabolic syndrome (MetS). We hypothesized that neutrophil infiltration into adipose tissue (AT) may occur at an early stage of MetS, in association with modulation of major functions of neutrophils and of their bone marrow production.

METHODS

Fifty-six male Sprague-Dawley rats were fed regular (control rats (CRs)) or high-fructose (60%; fructose-fed rats (FFRs)) diets. After 6 weeks, metabolic parameters were measured. Distribution of neutrophils into AT was investigated by immunohistochemistry. Function of circulating neutrophils (activation, reactive oxygen species production, phagocytosis, and apoptosis) was determined by flow cytometry. Granulopoiesis was evaluated by measuring the number and survival characteristics of neutrophil progenitors using bone marrow culture assays and flow cytometry.

RESULTS

Compared with the CR group, the FFR group developed MetS (i.e., arterial hypertension, hypertriglyceridemia, fasting hyperglycemia, and greater intra-abdominal AT volume) and presented higher neutrophil infiltration into AT. At resting state, no significant difference for circulating neutrophil functions was observed between the 2 groups. In contrast, circulating neutrophils from the FFR group exhibited higher responses to phorbol-12-myristate-13-acetate for all studied functions, compared with the CR group, suggesting that early MetS induces neutrophil priming. In parallel, a diminished clonal capacity and an increased apoptosis in bone marrow-derived granulocyte progenitors and neutrophil precursors were observed in the FFR group compared with the CR group.

CONCLUSIONS

These results provide evidence of an increased infiltration into intra-abdominal AT and modified production, function, and phenotype of neutrophils at an early stage of high-fructose diet-induced MetS.

Cellular changes in blood indicate severe respiratory disease during influenza infections in mice

Influenza A infection is a serious threat to human and animal health. Many of the biological mechanisms of the host-pathogen-interactions are still not well understood and reliable biomarkers indicating the course of the disease are missing. The mouse is a valuable model system enabling us to study the local inflammatory host response and the influence on blood parameters under controlled circumstances. Here, we compared the lung and peripheral changes after PR8 (H1N1) influenza A virus infection in C57BL/6J and DBA/2J mice using virus variants of different pathogenicity resulting in non-lethal and lethal disease. We monitored hematological and immunological parameters revealing that the granulocyte to lymphocyte ratio in the blood represents an early indicator of severe disease progression already two days after influenza A infection in mice. These findings might be relevant to optimize early diagnostic options of severe influenza disease and to monitor successful therapeutic treatment in humans.

Early detection and staging of spontaneous embryo resorption by ultrasound biomicroscopy in murine pregnancy

BACKGROUND

Embryo resorption is a major problem in human medicine, agricultural animal production and in conservation breeding programs. Underlying mechanisms have been investigated in the well characterised mouse model. However, post mortem studies are limited by the rapid disintegration of embryonic structures. A method to reliably identify embryo resorption in alive animals has not been established yet. In our study we aim to detect embryos undergoing resorption in vivo at the earliest possible stage by ultra-high frequency ultrasound.

METHODS

In a longitudinal study, we monitored 30 pregnancies of wild type C57BI/6 mice using ultra-high frequency ultrasound (30-70 MHz), so called ultrasound biomicroscopy (UBM). We compared the sonoembryology of mouse conceptuses under spontaneous resorption and neighbouring healthy conceptuses and correlated the live ultrasound data with the respective histology.

RESULTS

The process of embryo resorption comprised of four stages: first, the conceptus exhibited growth retardation, second, bradycardia and pericardial edema were observed, third, further development ceased and the embryo died, and finally embryo remnants were resorbed by maternal immune cells. In early gestation (day 7 and 8), growth retardation was characterized by a small embryonic cavity. The embryo and its membranes were ill defined or did not develop at all. The echodensity of the embryonic fluid increased and within one to two days, the embryo and its cavity disappeared and was transformed into echodense tissue surrounded by fluid filled caverns. In corresponding histologic preparations, fibrinoid material interspersed with maternal granulocytes and lacunae filled with maternal blood were observed. In later stages (day 9-11) resorption prone embryos were one day behind in their development compared to their normal siblings. The space between Reichert's membrane and inner yolk sac membrane was enlarged The growth retarded embryos exhibited bradycardia and ultimately cessation of heart beat. Corresponding histology showed apoptotic cells in the embryo while the placenta was still intact. In the subsequent resorption process first the embryo and then its membranes disappeared.

CONCLUSIONS

Our results provide a temporal time course of embryo resorption. With this method, animals exhibiting embryo resorption can be targeted, enabling the investigation of underlying mechanisms before the onset of total embryo disintegration.

Assessment of low-dose cisplatin as a model of nausea and emesis in beagle dogs, potential for repeated administration

Cisplatin is a highly emetogenic cancer chemotherapy agent, which is often used to induce nausea and emesis in animal models. The cytotoxic properties of cisplatin also cause adverse events that negatively impact on animal welfare preventing repeated administration of cisplatin. In this study, we assessed whether a low (subclinical) dose of cisplatin could be utilized as a model of nausea and emesis in the dog while decreasing the severity of adverse events to allow repeated administration. The emetic, nausea-like behavior and potential biomarker response to both the clinical dose (70 mg/m²) and low dose (15 mg/m²) of cisplatin was assessed. Plasma creatinine concentrations and granulocyte counts were used to assess adverse effects on the kidneys and bone marrow, respectively. Nausea-like behavior and emesis was induced by both doses of cisplatin, but the latency to onset was greater in the low-dose group. No significant change in plasma creatinine was detected for either dose groups. Granulocytes were significantly reduced compared with baseline (P = 0.000) following the clinical, but not the low-dose cisplatin group. Tolerability of repeated administration was assessed with 4 administrations of an 18 mg/m² dose cisplatin. Plasma creatinine did not change significantly. Cumulative effects on the granulocytes occurred, they were significantly decreased (P = 0.03) from baseline at 3 weeks following cisplatin for the 4th administration only. Our results suggest that subclinical doses (15 and 18 mg/m²) of cisplatin induce nausea-like behavior and emesis but have reduced adverse effects compared with the clinical dose allowing for repeated administration in crossover studies.

A phase 2 study of ruxolitinib, an oral JAK1 and JAK2 Inhibitor, in patients with advanced polycythemia vera who are refractory or intolerant to hydroxyurea

BACKGROUND

Polycythemia vera (PV) is a myeloproliferative neoplasm associated with somatic gain-of-function mutations of Januskinase-2 (JAK2). Therapeutic options are limited in patients with advanced disease. Ruxolitinib, an oral JAK1/JAK2 inhibitor, is active in preclinical models of PV. The long-term efficacy and safety of ruxolitinib in patients with advanced PV who are refractory or intolerant to hydroxyurea were studied in a phase 2 trial.

METHODS

Response was assessed using modified European LeukemiaNet criteria, which included a reduction in hematocrit to < 45% without phlebotomy, resolution of palpable splenomegaly, normalization of white blood cell and platelet counts, and reduction in PV-associated symptoms.

RESULTS

Thirty-four patients received ruxolitinib for a median of 152 weeks (range, 31 weeks-177 weeks) or 35.0 months (range, 7.1 months-40.7 months). Hematocrit < 45% without phlebotomy was achieved in 97% of patients by week 24. Only 1 patient required a phlebotomy after week 4. Among patients with palpable splenomegaly at baseline, 44% and 63%, respectively, achieved nonpalpable spleen measurements at weeks 24 and 144. Clinically meaningful improvements in pruritus, night sweats, and bone pain were observed within 4 weeks of the initiation of therapy and maintained with continued treatment. Ruxolitinib treatment also reduced elevated levels of inflammatory cytokines and granulocyte activation. Thrombocytopenia and anemia were the most common adverse events. Thrombocytopenia of ≥ grade 3 or anemia of ≥ grade 3 (according to National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0) occurred in 3 patients each (9%) (1 patient had both) and were managed with dose modification.

CONCLUSIONS

Ruxolitinib was generally well tolerated and provided rapid and durable clinical benefits in patients with advanced PV who were refractory or intolerant to hydroxyurea. Cancer 2014;120:513–20. © 2013 The Authors published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

In the current study, patients with polycythemia vera who were refractory or intolerant to hydroxyurea achieved clinically meaningful and durable benefit from treatment with ruxolitinib with respect to reductions in hematocrit, platelet and white blood cell counts, splenomegaly, and symptoms. Given the limited therapeutic options for patients with advanced polycythemia vera, these results suggest that ruxolitinib has the potential to address an important unmet medical need in this patient population.

Granulocyte, monocyte and blast immunophenotype abnormalities in acute myeloid leukemia with myelodysplasia-related changes

Little literature exists regarding granulocyte and monocyte immunophenotype abnormalities in Acute Myeloid Leukemia (AML). We hypothesized that granulocyte and monocyte immunophenotype abnormalities are common in AML, and especially in AML with myelodysplasia-related changes (AMLMRC). Bone marrow or peripheral blood specimens from 48 cases of AML and 22 cases of control specimens were analyzed by flow cytometric immunophenotyping. Granulocyte, monocyte, and blast immunophenotype abnormalities were compared between cases of AML versus controls and AMLMRC versus AML without myelodysplasia. The results revealed that granulocyte, monocyte, and blast abnormalities were more common in AMLMRC than in AML without myelodysplasia or control cases. The difference reached statistical significance for abnormalities of granulocytes and abnormalities in all cells of interest. From the numerous individual abnormalities, only CD25 expression in blasts was significantly more prevalent in AMLMRC in this study. We conclude that detection of granulocyte, monocyte, and blast immunophenotype abnormalities can contribute to the diagnosis of AMLMRC.

[Mutual role of factors of endotoxicosis and intra-abdominal hypertension syndrome in pathogenesis of abdominal sepsis]

The mutual role of the main factors of endotoxicosis and intraabdominal hypertension syndrome (IHS) were studied in pathogenesis of abdominal sepsis, basing on analysis of the treatment results in 156 patients, suffering this disease. The contents of neutrophils, macrophages, interleukins (IL-6, IL-10) were studied in peritoneal exudate as the indices of the source of inflammation in abdominal cavity. There was established the mutual strengthening of the endotoxicosis and IHS factors, what causes the clinical signs of the organ dysfunction, determines the course severity and outcome of pathological process in the organism. Such approach to pathogenesis of abdominal sepsis permits in time and adequately to elaborate the certain program of treatment in the patients.

Staphylococcus aureus recognition by hematopoietic stem and progenitor cells via TLR2/MyD88/PGE2 stimulates granulopoiesis in wounds

During bacterial infection, hematopoietic stem and progenitor cells (HSPCs) differentiate into polymorphonuclear leukocytes (PMNs) in the bone marrow. We reported that HSPCs recruited to Staphylococcus aureus-infected skin wounds in mice undergo granulopoiesis, whereas other authors have demonstrated their differentiation in vitro after Toll-like receptor 2 (TLR2)/MyD88 stimulation. Here, we examined this pathway in HSPC trafficking and granulopoiesis within S aureus-infected wounds. Lineage- HSPCs from TLR2- or MyD88-deficient mice injected into infected wounds of wild-type (WT) mice exhibited impaired granulopoiesis. However, HSPCs from WT mice produced similar numbers of PMNs whether transferred into wounds of TLR2-, MyD88-deficient, or WT mice. Prostaglandin E2 (PGE2), which stimulates HSPC survival and proliferation, was produced by HSPCs after TLR2 stimulation, suggesting that TLR2/MyD88 activation promotes granulopoiesis in part by production and autocrine activity of PGE2. Pretreatment of TLR2- or MyD88-deficient HSPCs with PGE2 rescued granulocytic differentiation in vivo. Finally, we demonstrate that bone marrow-derived lin-/Sca-1+/c-kit+ cells produced PGE2 and underwent granulopoiesis after TLR2 stimulation. lin-/Sca-1+/c-kit+ cells deficient in TLR2 or MyD88 produced PMNs after PGE2 treatment when transferred into uninfected wounds. We conclude that granulopoiesis in S aureus-infected wounds is induced by TLR2/MyD88 activation of HSPCs through a mechanism that involves autocrine production and activity of PGE2.

[Oxidative stress in blood leukocytes, pro/antioxidant status and fatty acids composition of pancreas lipids at experimental acute pancreatitis in rats]

In an experimental model of acute pancreatitis (AP) in rats no alteration in leukocyte's viability was found by flow cytometry as compared to control. After 1 day of AP production of reactive oxygen forms in granulocytes was increased more than 5 times, but after 3 days their level was decreased. Alterations of pro/antioxidant status and specific changes in the fatty acid composition in the pancreas were established. With the development of AP, the processes of lipids peroxidation were intensified while antioxidant system was altered, that was evidenced by inflammation in the pancreas. In these conditions, the increase of phospholipase A2 activity was accompanied by significant changes of fatty acid composition of the total lipids in the pancreas. This increased relative total content of saturated fatty acids, in particular myristic, palmitic and stearic acid increased, while the total content of polyunsaturated essential fatty acids omega-3 (linolenic, eicosapentaenoic, dokozapentayenoic, docosahexaenoic) decreased. The preparation containing omega-3 polyunsaturated fatty acids partially normalized the lipid and fatty acids composition as well as prooxidant-antioxidant system.

[Rational approach of leucocytosis in adults]

Several factors may influence the increased level of white blood cells (physical and/or emotional stimuli, infections, inflammations, drugs, toxins, etc.). The best approach to identify these disorders gets through a physical examination and a precise history. A particular attention should be focused on the onset of lymph nodes and/or splenomegaly. Among severe haematological disorders to take into consideration, we should exclude acute leukemias, chronic leukemias and myeloproliferative disorders.

The impact of Aspergillus fumigatus viability and sensitization to its allergens on the murine allergic asthma phenotype

Aspergillus fumigatus is a ubiquitously present respiratory pathogen. The outcome of a pulmonary disease may vary significantly with fungal viability and host immune status. Our objective in this study was (1) to assess the ability of inhaled irradiation-killed or live A. fumigatus spores to induce allergic pulmonary disease and (2) to assess the extent to which inhaled dead or live A. fumigatus spores influence pulmonary symptoms in a previously established allergic state. Our newly developed fungal delivery apparatus allowed us to recapitulate human exposure through repeated inhalation of dry fungal spores in an animal model. We found that live A. fumigatus spore inhalation led to a significantly increased humoral response, pulmonary inflammation, and airway remodeling in naïve mice and is more likely to induce allergic asthma symptoms than the dead spores. In contrast, in allergic mice, inhalation of dead and live conidia recruited neutrophils and induced goblet cell metaplasia. This data suggests that asthma symptoms might be exacerbated by the inhalation of live or dead spores in individuals with established allergy to fungal antigens, although the extent of symptoms was less with dead spores. These results are likely to be important while considering fungal exposure assessment methods and for making informed therapeutic decisions for mold-associated diseases.

Possible pitfalls investigating cell death responses in genetically engineered mouse models and derived cell lines

Genetically engineered mouse models are frequently used to identify pathophysiological consequences of deregulated cell death. Targeting pro-apoptotic or anti-apoptotic proteins of the extrinsic or intrinsic apoptotic signalling cascade is state of the art since more than two decades. Such animal models have been increasingly made use of over the past years to study loss- or gain-of-function consequences of one or more components of the molecular machinery leading to cell death. These studies have helped to separate redundant from non-redundant functions of apoptosis-related proteins in normal physiology and sometimes unravelled unexpected phenotypes. However, correct interpretation of data derived from knockout mice or derived cells and cell lines is often flawed by the comparison of cells originating from different inbred or mixed genetic backgrounds. Here we want to highlight some basic problems associated with genetic background-based modulation of cell death sensitivity and describe some methods that we use to investigate cell death responses in hematopoietic and non-hematopoietic cells. Thereby, we show that hematopoietic cells derived from wild type mice on a C57BL/6:129/SvJ recombinant mixed genetic background are significantly more resistant to spontaneous cell death or DNA-damage induced apoptosis in vitro than cells derived from inbred C57BL/6 mice. Furthermore, we show as an example that C57BL/6 mice are more susceptible to γ-irradiation induced cell death after whole body irradiation in vivo and subsequent T cell lymphomagenesis.

Genista sessilifolia DC. extracts induce apoptosis across a range of cancer cell lines

OBJECTIVES

Restorative properties of medicinal plants such as Genista sessilifolia DC. have often been suggested to occur, in epidemiological studies. However, full characterization of effective principles responsible for this action has never previously been performed. Here, we have characterized G. sessilifolia's anti-cancer effects and identified the chemical components involved in this anti-tumour action.

MATERIALS AND METHODS

Cell cycle, apoptosis, necrosis, differentiation analyses, high-performance liquid chromatography, western blotting, RNA extraction, real-time PCR and primers have all been observed/used in the study.

RESULTS

We report that G. sessilifolia methanol extract has anti-cancer activity on solid and haematological cancer cells. G. sessilifolia extract's anti-proliferative action is closely bound to induction of apoptosis, whereas differentiation is only weakly modulated. Analysis of G. sessilifolia extract, by high-performance liquid chromatography, identifies fraction 18-22 as the pertinent component for induction of apoptosis, whereas fractions 11-13 and 27-30 both seem to contribute to differentiation. G. sessilifolia extract induces apoptosis mediated by caspase activation and p21, Rb, p53, Bcl2-associated agonist of cell death (BAD), tumour necrosis factor receptor super-family, member 10 (TRAIL) overexpression and death receptor 5 (DR5). Accordingly, fraction 18-22 inducing apoptosis was able to induce TRAIL.

CONCLUSIONS

Our results indicate that G. sessilifolia extract and its fraction 18-22 containing genistin and isoprunetin, were able to induce anti-cancer effects supporting the hypothesis of a pro-apoptotic intrinsic content of this natural medicinal plant.

Identification of CD68(+) neutrophil granulocytes in in vitro model of acute inflammation and inflammatory bowel disease

CD-68 is widely regarded as a selective marker for human monocytes and macrophages and is commonly used in human pathology studies. The purpose of this study was to investigate the expression of CD-68 in human peripheral blood mononuclear cells (PBMCs), neutrophil granulocytes (NGs) and in inflamed intestinal tissue samples for comparison. PBMCs and NGs were isolated from heparinized human blood samples. Intestinal biopsies were obtained during routine endoscopic procedures from patients with inflammatory bowel disease (IBD), e.g. ulcerative colitis and Crohn's disease. Gene and protein expression was analyzed by real-time RT-PCR, Western blot and immunohistochemistry. Both PBMCs and NGs preparations contained cells that were positive for CD-68 and either neutrophil elastase (NE), or myeloperoxidase (MPO). CD-68(+)/NE(-)/MPO(-) cells were regarded as monocytes. CD-68 mRNA expression was detected in PBMCs and NGs preparations. With Western blot and by performing immunoprecipitation of cell lysate, we could clearly detect CD-68 in NGs, U-937, THP-1, Hep-G2, Jurkat cells and PBMCs. Identification of inflammatory cells in acutely inflamed colonic mucosa obtained from patients with IBD revealed a strong accumulation of CD-68(+)/MPO(+) cells compared to normal colonic mucosa. The uptake of the marker by phagocytosis was excluded by performing a double staining with CD-163/NE and CD-163/MPO in PBMCs, NGs cultures and in inflamed colonic mucosa. These results identify CD-68(+) NGs in peripheral blood and inflamed colonic mucosa. CD-68 is not only a marker for the macrophages-monocytes but also for NGs.

The neurovascular unit as a selective barrier to polymorphonuclear granulocyte (PMN) infiltration into the brain after ischemic injury

The migration of polymorphonuclear granulocytes (PMN) into the brain parenchyma and release of their abundant proteases are considered the main causes of neuronal cell death and reperfusion injury following ischemia. Yet, therapies targeting PMN egress have been largely ineffective. To address this discrepancy we investigated the temporo-spatial localization of PMNs early after transient ischemia in a murine transient middle cerebral artery occlusion (tMCAO) model and human stroke specimens. Using specific markers that distinguish PMN (Ly6G) from monocytes/macrophages (Ly6C) and that define the cellular and basement membrane boundaries of the neurovascular unit (NVU), histology and confocal microscopy revealed that virtually no PMNs entered the infarcted CNS parenchyma. Regardless of tMCAO duration, PMNs were mainly restricted to luminal surfaces or perivascular spaces of cerebral vessels. Vascular PMN accumulation showed no spatial correlation with increased vessel permeability, enhanced expression of endothelial cell adhesion molecules, platelet aggregation or release of neutrophil extracellular traps. Live cell imaging studies confirmed that oxygen and glucose deprivation followed by reoxygenation fail to induce PMN migration across a brain endothelial monolayer under flow conditions in vitro. The absence of PMN infiltration in infarcted brain tissues was corroborated in 25 human stroke specimens collected at early time points after infarction. Our observations identify the NVU rather than the brain parenchyma as the site of PMN action after CNS ischemia and suggest reappraisal of targets for therapies to reduce reperfusion injury after stroke.

Inhibition of the NAD-dependent protein deacetylase SIRT2 induces granulocytic differentiation in human leukemia cells

Sirtuins, NAD-dependent protein deacetylases, play important roles in cellular functions such as metabolism and differentiation. Whether sirtuins function in tumorigenesis is still controversial, but sirtuins are aberrantly expressed in tumors, which may keep cancerous cells undifferentiated. Therefore, we investigated whether the inhibition of sirtuin family proteins induces cellular differentiation in leukemic cells. The sirtuin inhibitors tenovin-6 and BML-266 induce granulocytic differentiation in the acute promyelocytic leukemia (APL) cell line NB4. This differentiation is likely caused by an inhibition of SIRT2 deacetylase activity, judging from the accumulation of acetylated α-tubulin, a major SIRT2 substrate. Unlike the clinically used differentiation inducer all-trans retinoic acid, tenovin-6 shows limited effects on promyelocytic leukemia-retinoic acid receptor α (PML-RAR-α) stability and promyelocytic leukemia nuclear body formation in NB4 cells, suggesting that tenovin-6 does not directly target PML-RAR-α activity. In agreement with this, tenovin-6 induces cellular differentiation in the non-APL cell line HL-60, where PML-RAR-α does not exist. Knocking down SIRT2 by shRNA induces granulocytic differentiation in NB4 cells, which demonstrates that the inhibition of SIRT2 activity is sufficient to induce cell differentiation in NB4 cells. The overexpression of SIRT2 in NB4 cells decreases the level of granulocytic differentiation induced by tenovin-6, which indicates that tenovin-6 induces granulocytic differentiation by inhibiting SIRT2 activity. Taken together, our data suggest that targeting SIRT2 is a viable strategy to induce leukemic cell differentiation.

[Effect of chronic sensorineural hearing loss on several indicators of immune and endocrine systems of 7-11 year-old children]

We investigated the effects of chronic bilateral sensorineural hearing loss of III-IV degree on the performance of interleukins, immunoglobulins serum and saliva, the functional activity of granulocyte-monocyte cell immunity, evaluated the activity of the hypothalamic-pituitary-adrenal system in children aged 7-11 years. It was found that due to stress activation of the sympathetic-adrenal system the function of granulocytes and monocytes is suppressed, with a predominance of production of anti-inflammatory interleukins. This leads to the dominance of T-helper type 2. Products granulocytes and T-helper type-2 anti-inflammatory interleukins IL-4, IL-5, IL-10, IL-13 leads to the activation of B-cells. Thus, in children 7-11 years of age with congenital bilateral sensorineural hearing loss is a decrease of non-specific humoral immunity dominated type of immune response to increased levels of IgG.

Granulocyte maturation determines ability to release chromatin NETs and loss of DNA damage response; these properties are absent in immature AML granulocytes

Terminally-differentiated cells cease to proliferate and acquire specific sets of expressed genes and functions distinguishing them from less differentiated and cancer cells. Mature granulocytes show lobular structure of cell nuclei with highly condensed chromatin in which HP1 proteins are replaced by MNEI. These structural features of chromatin correspond to low level of gene expression and the loss of some important functions as DNA damage repair, shown in this work and, on the other hand, acquisition of a new specific function consisting in the release of chromatin extracellular traps in response to infection by pathogenic microbes. Granulocytic differentiation is incomplete in myeloid leukemia and is manifested by persistence of lower levels of HP1γ and HP1β isoforms. This immaturity is accompanied by acquisition of DDR capacity allowing to these incompletely differentiated multi-lobed neutrophils of AML patients to respond to induction of DSB by γ-irradiation. Immature granulocytes persist frequently in blood of treated AML patients in remission. These granulocytes contrary to mature ones do not release chromatin for NETs after activation with phorbol myristate-12 acetate-13 and do not exert the neutrophil function in immune defence. We suggest therefore the detection of HP1 expression in granulocytes of AML patients as a very sensitive indicator of their maturation and functionality after the treatment. Our results show that the changes in chromatin structure underlie a major transition in functioning of the genome in immature granulocytes. They show further that leukemia stem cells can differentiate ex vivo to mature granulocytes despite carrying the translocation BCR/ABL.

Impact of 5-lipoxygenase inhibitors on the spatiotemporal distribution of inflammatory cells and neuronal COX-2 expression following experimental traumatic brain injury in rats

The inflammatory response following traumatic brain injury (TBI) contributes to neuronal death with poor outcome. Although anti-inflammatory strategies were beneficial in the experimental TBI, clinical translations mostly failed, probably caused by the complexity of involved cells and mediators. We recently showed in a rat model of controlled cortical impact (CCI) that leukotriene inhibitors (LIs) attenuate contusion growth and improve neuronal survival. This study focuses on spatiotemporal characteristics of macrophages and granulocytes, typically involved in inflammatory processes, and neuronal COX-2 expression. Effects of treatment with LIs (Boscari/MK-886), started prior trauma, were evaluated by quantifying CD68(+), CD43(+) and COX-2(+) cells 24h and 72 h post-CCI in the parietal cortex (PC), CA3 region, dentate gyrus (DG) and visual/auditory cortex (v/aC). Correlations were applied to identify intercellular relationships. At 24h, untreated animals showed granulocyte invasion in all regions, decreasing towards 72 h. Macrophages increased from 24h to 72 h post-CCI in PC and v/aC. COX-2(+) neurones showed no temporal changes, except of an increase in the CA3 region at 72 h. Treatment reduced granulocytes at 24h in the pericontusional zone and hippocampus, and macrophages at 72 h in the PC and v/aC. COX-2 expression remained unaffected by LIs, except of time-specific changes in the DG (increase/decrease at 24/72 h). Interrelations confirmed concomitant cellular reactions beyond the initial trauma site. In conclusion, LIs attenuated the cellular inflammatory response following CCI. Future studies have to clarify region-specific effects and explore the potential of a clinically more relevant therapeutic approach applying LIs after CCI.

[The dysplasia of myelopoiesis in patients with acute lymphoblastic leucosis]

Nowadays, the analysis of hematopoiesis in patients with acute lymphoblastic leucosis includes only quantitative characteristics of residue myeloid process of bone marrow. The evaluation of myelodysplasia is unexplored still. The analysis of myelopoiesis was carried on sampling of 108 patients with primary acute lymphoblastic leucosis (27 - T-acute lymphohlastic leucosis, 81 - B-acute Iymphoblastic leucosis). The characteristics of dysplasia of granulocytes, erythroid cells and megakaryocytes were based on the parameters of WHO classification of acute myeloid leucosis (2001). The monolinear dysplasia was established in 35 patients (32.4%). multilinear dysplasia--in 9 patients (8.3%). Under T- acute lymphoblastic leucosis the bilinear dysplasia was detected reliably more often and absence of dysplasia more rare than under B-acute lymphoblastic leucosis. The signs of dysplasia of various myeloid lines had no inter-correlation and had no dependencies from indicators of expression of early antigens (CCD34 and TdT) and myeloid antigens (CD13, CD33). The comparison of factual data with indicators of dysplasia under acute mteloid leucosis (181 patients) demonstrated that rates of uni- and multilinear dysplasia under T-acute Iymphoblastic leucosis and acute myeloid leucosis have no significant difference. The myelodysplasia is detected reliably (more often under B-acute lymphoblastic leucosis as compared with acute myeloid leucosis.

Skin own bacteria may aggravate inflammatory and occlusive changes in atherosclerotic arteries of lower limbs

AIM

Seroepidemiological studies have given rise to the hypothesis that microorganisms like Chlamydia pneumoniae (CP), Helicobacter pylori (HP), cytomegalovirus (CMV), HCV types 1 and 2, and bacteria involved in dental or other unspecified infection sites may initiate or maintain the atherosclerotic process in lower limb arteries. However, not much attention has been attached to the patient's own limb skin and deep tissues bacterial flora, activated in ischemic tissues. This flora may enhance the inflammatory and thrombotic process in the atherosclerotic arteries. Lower limb tissues are exposed to microorganisms from the environment (foot) and microbes on floating epidermal cells from the perineal and anal regions. The aim of this paper was to identify microbial cells and their DNA in perivascular tissues and arterial walls of lower limbs.

METHODS

Bacterial cultures and PCR method for detection of 16sRNA and immunohistopathological staining for identification of immune cells infiltrating vascular bundles.

RESULTS

1) specimens of atherosclerotic calf and femoral arteries contained bacterial isolates and/or their DNA, whereas, in control normal cadaveric organ donors' limb arteries or patients' carotid arteries and aorta bacteria they were detected only sporadically; 2) lower limb lymphatics contained bacterial cells in 76% of specimens, whereas controls only in 10%; 3) isolates from limb arteries and lymphatics belonged in majority to the coagulase-negative staphylococci and S.aureus, however, other highly pathogenic strains were also detected; 4) immunohistopathological evaluation arterial walls showed dense focal infiltrates of granulocytes and macrophages.

CONCLUSION

Own bacterial isolates can be responsible for dense neutrophil and macrophage inflitrates of atherosclerotic walls and periarterial tissue in lower limbs and aggravate the ischemic changes.

An emerging link in stem cell mobilization between activation of the complement cascade and the chemotactic gradient of sphingosine-1-phosphate

Under steady-state conditions, hematopoietic stem/progenitor cells (HSPCs) egress from bone marrow (BM) and enter peripheral blood (PB) where they circulate at low levels. Their number in PB, however, increases significantly in several stress situations related to infection, organ/tissue damage, or strenuous exercise. Pharmacologically mediated enforced egress of HSPCs from the BM microenvironment into PB is called "mobilization", and this phenomenon has been exploited in hematological transplantology as a means to obtain HSPCs for hematopoietic reconstitution. In this review we will present the accumulated evidence that innate immunity, including the complement cascade and the granulocyte/monocyte lineage, and the PB plasma level of the bioactive lipid sphingosine-1-phosphate (S1P) together orchestrate this evolutionarily conserved mechanism that directs trafficking of HSPCs.

Granulocytes and vascularization regulate uterine bleeding and tissue remodeling in a mouse menstruation model

Menstruation-associated disorders negatively interfere with the quality of life of many women. However, mechanisms underlying pathogenesis of menstrual disorders remain poorly investigated up to date. Among others, this is based on a lack of appropriate pre-clinical animal models. We here employ a mouse menstruation model induced by priming mice with gonadal hormones and application of a physical stimulus into the uterus followed by progesterone removal. As in women, these events are accompanied by menstrual-like bleeding and tissue remodeling processes, i.e. disintegration of decidualized endometrium, as well as subsequent repair. We demonstrate that the onset of bleeding coincides with strong upregulation of inflammatory mediators and massive granulocyte influx into the uterus. Uterine granulocytes play a central role in regulating local tissue remodeling since depletion of these cells results in dysregulated expression of matrix modifying enzymes. As described here for the first time, uterine blood loss can be quantified by help of tampon-like cotton pads. Using this novel technique, we reveal that blood loss is strongly reduced upon inhibition of endometrial vascularization and thus, is a key regulator of menstrual bleeding. Taken together, we here identify angiogenesis and infiltrating granulocytes as critical determinants of uterine bleeding and tissue remodeling in a mouse menstruation model. Importantly, our study provides a technical and scientific basis allowing quantification of uterine blood loss in mice and thus, assessment of therapeutic intervention, proving great potential for future use in basic research and drug discovery.

Pulmonary inflammatory reaction and structural changes induced by cigarette smoke exposure in the Guinea pig

Cigarette smoke (CS) induces an inflammatory process in the lung that may underlie the development of chronic obstructive pulmonary disease (COPD). The nature and characteristics of this process have not been fully established in animal models. We aimed to evaluate the pulmonary inflammatory reaction and its involvement in structural changes in guinea pigs chronically exposed to CS. 19 Hartley guinea pigs were exposed to 7 cigarettes/day, during 3 or 6 months. 18 control guinea pigs were sham-exposed. Numbers of neutrophils, macrophages and eosinophils and lymphoid follicles were assessed in different lung structures. Airway and vessel morphometry, alveolar space size and collagen deposition were also quantified. After 6 months of exposure, CS-exposed guinea pigs showed increased numbers of neutrophils, macrophages and eosinophils in the airways, intrapulmonary vessels and alveolar septa, as well as lymphoid follicles. Increased numbers of muscularized intrapulmonary vessels were apparent at 3 months. After 6 months of exposure, the airway wall thickened and the alveolar space size increased. Collagen deposition was also apparent in airway walls and alveolar septa after 6 months' exposure. The magnitude of airway wall-thickening correlated with the number of infiltrating inflammatory cells, and the extension of collagen deposition correlated with alveolar space size. We conclude that in the guinea pig, 6 months of CS exposure induces inflammatory cell infiltrate in lung structures, at an intensity that correlates with airway remodelling. These changes resemble those observed in COPD, thus endorsing the pathogenic role of CS and the usefulness of this animal model for its study.

Up-regulation of Annexin-A1 and lipoxin A(4) in individuals with ulcerative colitis may promote mucosal homeostasis

Background

One of the characteristics of an active episode of ulcerative colitis (UC) is the intense mucosal infiltration of leukocytes. The pro-resolution mediators Annexin-A1 (AnxA1) and lipoxin A₄ (LXA₄) exert counter-regulatory effects on leukocyte recruitment, however to date, the dual/cumulative effects of these formyl peptide receptor-2 (FPR2/ALX) agonists in the context of human intestinal diseases are unclear. To define the contribution of these mediators, we measured their expression in biopsies from individuals with UC.

Methods

Colonic mucosal biopsies were collected from two broad patient groups: healthy volunteers without (‘Ctrl’ n = 20) or with a prior history of UC (‘hx of UC’ n = 5); individuals with UC experiencing active disease (‘active’ n = 8), or in medically-induced remission (‘remission’ n = 16). We assessed the mucosal expression of LXA₄, AnxA1, and the FPR2/ALX receptor in each patient group using a combination of fluorescence microscopy, biochemical and molecular analyses.

Results

Mucosal expression of LXA₄ was elevated exclusively in biopsies from individuals in remission (3-fold, P<0.05 vs. Ctrl). Moreover, in this same group we observed an upregulation of AnxA1 protein expression (2.5-fold increase vs. Ctrl, P<.01), concurrent with an increased level of macrophage infiltration, and an elevation in FPR2/ALX mRNA (7-fold increase vs. Ctrl, P<.05). Importantly, AnxA1 expression was not limited to cells infiltrating the lamina propria but was also detected in epithelial cells lining the intestinal crypts.

Conclusions

Our results demonstrate a specific up-regulation of this pro-resolution circuit in individuals in remission from UC, and suggest a significant role for LXA₄ and AnxA1 in promoting mucosal homeostasis.