Karolina Bukowska-Strakova

Monoclonal antibodies against macrophage colony-stimulating factor diminish the number of circulating intermediate and nonclassical (CD14++CD16+/CD14+CD16++) monocytes in rheumatoid arthritis patient

To the editor: Human blood monocytes are divided into 3 subsets: classical (CD14++CD16−), intermediate (CD14++CD16+), and nonclassical (CD14+CD16++).[1][1] The latter 2 subpopulations produce inflammatory cytokines in response to a wide variety of pattern receptor ligands and are constantly

Nrf2 Regulates Angiogenesis: Effect on Endothelial Cells, Bone Marrow-Derived Proangiogenic Cells and Hind Limb Ischemia

AIMS Nuclear factor E2-related factor 2 (Nrf2), a key cytoprotective transcription factor, regulates also proangiogenic mediators, interleukin-8 and heme oxygenase-1 (HO-1). However, hitherto its role in blood vessel formation was modestly examined. Particularly, although Nrf2 was shown to affect hematopoietic stem cells, it was not tested in bone marrow-derived proangiogenic cells (PACs). Here we investigated angiogenic properties of Nrf2 in PACs, endothelial cells, and inflammation-related revascularization. RESULTS Treatment of endothelial cells with angiogenic cytokines increased nuclear localization of Nrf2 and induced expression of HO-1. Nrf2 activation stimulated a tube network formation, while its inhibition decreased angiogenic response of human endothelial cells, the latter effect reversed by overexpression of HO-1. Moreover, lack of Nrf2 attenuated survival, proliferation, migration, and angiogenic potential of murine PACs and affected angiogenic transcriptome in vitro. Additionally, angiogenic capacity of PAC Nrf2(-/-) in in vivo Matrigel assay and PAC mobilization in response to hind limb ischemia of Nrf2(-/-) mice were impaired. Despite that, restoration of blood flow in Nrf2-deficient ischemic muscles was better and accompanied by increased oxidative stress and inflammatory response. Accordingly, the anti-inflammatory agent etodolac tended to diminish blood flow in the Nrf2(-/-) mice. INNOVATION Identification of a novel role of Nrf2 in angiogenic signaling of endothelial cells and PACs. CONCLUSION Nrf2 contributes to angiogenic potential of both endothelial cells and PACs; however, its deficiency increases muscle blood flow under tissue ischemia. This might suggest a proangiogenic role of inflammation in the absence of Nrf2 in vivo, concomitantly undermining the role of PACs in such conditions.

Murine Bone Marrow Lin−Sca-1+CD45− Very Small Embryonic-Like (VSEL) Cells Are Heterogeneous Population Lacking Oct-4A Expression

Murine very small embryonic-like (VSEL) cells, defined by the Lin−Sca-1+CD45− phenotype and small size, were described as pluripotent cells and proposed to be the most primitive hematopoietic precursors in adult bone marrow. Although their isolation and potential application rely entirely on flow cytometry, the immunophenotype of VSELs has not been extensively characterized. Our aim was to analyze the possible heterogeneity of Lin−Sca+CD45− population and investigate the extent to which VSELs characteristics may overlap with that of hematopoietic stem cells (HSCs) or endothelial progenitor cells (EPCs). The study evidenced that murine Lin−Sca-1+CD45− population was heterogeneous in terms of c-Kit and KDR expression. Accordingly, the c-Kit+KDR−, c-Kit−KDR+, and c-Kit−KDR− subpopulations could be distinguished, while c-Kit+KDR+ events were very rare. The c-Kit+KDR− subset contained almost solely small cells, meeting the size criterion of VSELs, in contrast to relatively bigger c-Kit−KDR+ cells. The c-Kit−KDR−FSClow subset was highly enriched in Annexin V-positive, apoptotic cells, hence omitted from further analysis. Importantly, using qRT-PCR, we evidenced lack of Oct-4A and Oct-4B mRNA expression either in whole adult murine bone marrow or in the sorted of Lin−Sca-1+CD45−FSClow population, even by single-cell qRT-PCR. We also found that the Lin−Sca-1+CD45−c-Kit+ subset did not exhibit hematopoietic potential in a single cell-derived colony in vitro assay, although it comprised the Sca-1+c-Kit+Lin− (SKL) CD34−CD45−CD105+ cells, expressing particular HSC markers. Co-culture of Lin−Sca-1+CD45−FSClow with OP9 cells did not induce hematopoietic potential. Further investigation revealed that SKL CD45−CD105+ subset consisted of early apoptotic cells with fragmented chromatin, and could be contaminated with nuclei expelled from erythroblasts. Concluding, murine bone marrow Lin−Sca-1+CD45−FSClow cells are heterogeneous population, which do not express the pluripotency marker Oct-4A. Despite expression of some hematopoietic markers by a Lin−Sca-1+CD45−c-Kit+KDR− subset of VSELs, they do not display hematopoietic potential in a clonogenic assay and are enriched in early apoptotic cells.

Heme Oxygenase-1 Is Required for Angiogenic Function of Bone Marrow-Derived Progenitor Cells: Role in Therapeutic Revascularization

AIMS Heme oxygenase-1 (HO-1) is a cytoprotective enzyme that can be down-regulated in diabetes. Its importance for mature endothelium has been described, but its role in proangiogenic progenitors is not well known. We investigated the effect of HO-1 on the angiogenic potential of bone marrow-derived cells (BMDCs) and on blood flow recovery in ischemic muscle of diabetic mice. RESULTS Lack of HO-1 decreased the number of endothelial progenitor cells (Lin(-)CD45(-)cKit(-)Sca-1(+)VEGFR-2(+)) in murine bone marrow, and inhibited the angiogenic potential of cultured BMDCs, affecting their survival under oxidative stress, proliferation, migration, formation of capillaries, and paracrine proangiogenic potential. Transcriptome analysis of HO-1(-/-) BMDCs revealed the attenuated up-regulation of proangiogenic genes in response to hypoxia. Heterozygous HO-1(+/-) diabetic mice subjected to hind limb ischemia exhibited reduced local expression of vascular endothelial growth factor (VEGF), placental growth factor (PlGF), stromal cell-derived factor 1 (SDF-1), VEGFR-1, VEGFR-2, and CXCR-4. This was accompanied by impaired revascularization of ischemic muscle, despite a strong mobilization of bone marrow-derived proangiogenic progenitors (Sca-1(+)CXCR-4(+)) into peripheral blood. Blood flow recovery could be rescued by local injections of conditioned media harvested from BMDCs, but not by an injection of cultured BMDCs. INNOVATION This is the first report showing that HO-1 haploinsufficiency impairs tissue revascularization in diabetes and that proangiogenic in situ response, not progenitor cell mobilization, is important for blood flow recovery. CONCLUSIONS HO-1 is necessary for a proper proangiogenic function of BMDCs. A low level of HO-1 in hyperglycemic mice decreases restoration of perfusion in ischemic muscle, which can be rescued by a local injection of conditioned media from cultured BMDCs.

The B-cell Compartment in the Peripheral Blood of Children With Different Types of Primary Humoral Immunodeficiency

The aim of this study was to evaluate the B-cell compartment in the peripheral blood of children with different types of hipogammaglobulinemia: common variable immunodeficiency (CVID), transient hypogammaglobulinemia of infancy (THI), and selective IgA deficiency (SIgAD). We analyzed by flow cytometry the changes in the B-cell subsets with age and showed that children with an early-onset CVID develop similar pattern of B-cell subsets as adult patients with CVID with age, as the levels of memory B cells (CD19+/CD27+) and class-switched memory B cells (CD19+/CD27+/IgD−/IgM−), in contrast to age-matched control group, did not increase with age. Children with SIgAD displayed similar changes as patients with CVID only within the class-switched memory B-cell subpopulation. No significant differences in the level of memory B cells and class-switched memory B cells in children with THI in comparison to age-matched control group were observed. There were no differences in the percentage of immature B cells (CD19+/CD21low) among all studied groups. As B-cell subsets in children with THI were normal during entire period of hypogammaglobulinemia, the persistence of low levels of memory B-cell subsets in some children may facilitate the diagnosis of CVID.

Rutabaga (Brassica napus L. var. napobrassica) seeds, roots, and sprouts: a novel kind of food with antioxidant properties and proapoptotic potential in Hep G2 hepatoma cell line.

Although rutabaga (Brassica napus L. var. napobrassica) is a popular crop, especially in North Europe and North America, its sprouts are a new kind of vegetable. Rutabaga roots, and particularly sprouts, have not been investigated so far for antioxidant and anticancer effect on human tumor cells (Hep G2). Therefore, in vitro tests were conducted to find out whether rutabaga seeds, roots, and sprouts exert a cytotoxic effect on mammalian cells and combine them with other biological properties of particular parts of the plant. Rutabaga methanol extracts were measured for total phenolic, total flavonoid concentrations, and total antioxidant activity. Cytotoxicity of the investigated extracts was measured using 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide assay in Chinese hamster ovary cells (CHO-K1) and Hep G2 cells culture. Cell membrane integrity was assessed in CHO-K1 and Hep G2 cells by luminescence ToxiLight BioAssay. The results of the investigation have shown that sprouts have significantly higher antioxidant activity than seeds and roots, which may result from different contents of polyphenols. Rutabaga extracts (especially 8 day sprouts) inhibited the tumor cell line Hep G2 proliferation and had a slight effect on the normal mammalian CHO-K1 culture. An advanced analysis of previously observed morphological changes and cytotoxic properties demonstrated that the evaluated extracts exerted cell death via apoptosis. These findings strongly suggest that one of the biological activities of rutabaga is antiproliferative and proapoptotic potential specific to tumor cells. The obtained results demonstrate the antioxidant property of rutabaga and its potential as a nutritional supplement in cancer prevention. These findings also strongly advocate the application of rutabaga sprouts (especially harvested in conditions presented in this article) in functional food.

Familial occurrence of warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome

Introduction:Warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome is a rare immunodeficiency disorder with an autosomal-dominant pattern of inheritance and low fatality rate but significant lifelong morbidity.Materials and Methods:A 27-year-old mother of two children has been suffering from severe neutropenia and recurrent infections with the diagnosis of sporadic WHIM syndrome established by sequencing the CXCR4 gene and the finding of a heterozygous 1000 C→T nonsense mutation in the second CXCR4 exon. The first child was an apparently healthy boy delivered at full term. Umbilical cord blood cells were obtained for genetic analysis. Peripheral blood cells were also analyzed at 8 months of life. Both analyses revealed the same mutation as that of his mother. The child was in a good condition, manifesting neutropenia without infections until 11 months of life. He subsequently developed pneumonia requiring a more aggressive treatment. After that, the regular substitution of immunoglobulins (IVIGs) and G-CSF has been preventing serious infections. Six months ago the second boy was delivered who also demonstrated neutropenia without severe infections. Genetic studies using cord blood and also peripheral blood cells in the fourth month showed an identical mutation of the CXCR4 gene as in his mother. Moreover, the mother and her first son demonstrated monocytopenia.Results:The results indicate that genetic defects connected with WHIM syndrome may influence not only the granulocyte, but also the monocytic lineage. Moreover, a perinatal diagnosis of WHIM syndrome made by sequencing the CXCR4 gene should be performed in cases where either parent is known to be affected with this disease.Conclusions:This would facilitate an earlier detection of the deficiency in children, thereby allowing a more comprehensive follow-up and administration of appropriate therapy.

Number of circulating pro-angiogenic cells, growth factor and anti-oxidative gene profiles might be altered in type 2 diabetes with and without diabetic foot syndrome

Type 2 diabetes is often complicated by diabetic foot syndrome (DFS). We analyzed the circulating stem cells, growth factor and anti‐oxidant gene expression profiles in type 2 diabetes patients without or with different forms of DFS.

Exercise training in intermittent claudication: Effects on antioxidant genes, inflammatory mediators and proangiogenic progenitor cells

Exercise training remains a therapy of choice in intermittent claudication (IC). However, too exhaustive exercise may cause ischaemic injury and inflammatory response. We tested the impact of three-month treadmill training and single treadmill exercise on antioxidant gene expressions, cytokine concentrations and number of marrow-derived proangiogenic progenitor cells (PPC) in the blood of IC patients. Blood samples of 12 patients were collected before and after training, before and 1, 3 and 6 hours after the single exercise. PPCs were analysed with flow cytometry, cytokine concentrations were checked with Milliplex MAP, while expression of mRNAs and miRNAs was evaluated with qRT-PCR. Treadmill training improved pain-free walking time (from 144 ± 44 seconds [s] to 311 ± 134 s, p=0.02) and maximum walking time (from 578 ± 293 s to 859 ± 423 s, p=0.01) in IC patients. Before, but not after training, the single treadmill exercise increased the number of circulating CD45dimCD34+CD133-KDR+ PPCs (p=0.048), decreased expression of HMOX1 (p=0.04) in circulating leukocytes, reduced tumour necrosis factor-α (p=0.03) and tended to elevate myeloperoxidase (p=0.06) concentrations in plasma. In contrast, total plasminogen activator inhibitor-1 was decreased by single exercise only after, but not before training (p=0.02). Both before and after training the single exercise decreased monocyte chemoattractant protein (MCP)-1 (p=0.006 and p=0.03) concentration and increased SOD1 (p=0.001 and p=0.01) expression. Patients after training had also less interleukin-6 (p=0.03), but more MCP-1 (p=0.04) in the blood. In conclusion, treadmill training improves walking performance of IC patients, attenuates the single exercise-induced changes in gene expressions or PPC mobilisation, but may also lead to higher production of some proinflammatory cytokines.

Splenic Ly6Chi monocytes contribute to adverse late post-ischemic left ventricular remodeling in heme oxygenase-1 deficient mice

Heme oxygenase-1 (Hmox1) is a stress-inducible protein crucial in heme catabolism. The end products of its enzymatic activity possess anti-oxidative, anti-apoptotic and anti-inflammatory properties. Cardioprotective effects of Hmox1 were demonstrated in experimental models of myocardial infarction (MI). Nevertheless, its importance in timely resolution of post-ischemic inflammation remains incompletely understood. The aim of this study was to determine the role of Hmox1 in the monocyte/macrophage-mediated cardiac remodeling in a mouse model of MI. Hmox1 knockout (Hmox1−/−) and wild-type (WT, Hmox1+/+) mice were subjected to a permanent ligation of the left anterior descending coronary artery. Significantly lower incidence of left ventricle (LV) free wall rupture was noted between 3rd and 5th day after MI in Hmox1−/− mice resulting in their better overall survival. Then, starting from 7th until 21st day post-MI a more potent deterioration of LV function was observed in Hmox1−/− than in the surviving Hmox1+/+ mice. This was accompanied by higher numbers of Ly6Chi monocytes in peripheral blood, as well as higher expression of monocyte chemoattractant protein-1 and adhesion molecules in the hearts of MI-operated Hmox1−/− mice. Consequently, a greater post-MI monocyte-derived myocardial macrophage infiltration was noted in Hmox1-deficient individuals. Splenectomy decreased the numbers of circulating inflammatory Ly6Chi monocytes in blood, reduced the numbers of proinflammatory cardiac macrophages and significantly improved the post-MI LV function in Hmox1−/− mice. In conclusion, Hmox1 deficiency has divergent consequences in MI. On the one hand, it improves early post-MI survival by decreasing the occurrence of cardiac rupture. Afterwards, however, the hearts of Hmox1-deficient mice undergo adverse late LV remodeling due to overactive and prolonged post-ischemic inflammatory response. We identified spleen as an important source of these cardiovascular complications in Hmox1−/− mice.