Cell Chemotactic Factor Research Articles

Cosmetic implant placement in the female breast yields an altered local and systemic immune response: evidence for breast cancer immunosurveillance.

Women with cosmetic implants have lower rates of future breast cancer than the general population. We hypothesized the implant foreign body response could induce a local protective anti-cancer immunosurveillance. We expanded on our previous finding which showed women with breast implants have elevated antibody responses to certain breast cancer proteins. Blood samples and breast tissue were collected from women undergoing first time breast augmentation (implant-naive, IN) and revision breast augmentation (implant-exposed, IE). Sera were collected and antibody levels to common breast cancer proteins were quantified by enzyme-linked immunosorbent assay (ELISA). RT-PCR was performed on breast tissue samples to quantify immune-related gene expression levels between IN and IE. Bulk RNA sequencing was performed to identify differentially expressed genes and altered signaling pathways in the breasts of IN versus IE. In total, 188 patients were recruited (117 IN, 71 IE). Data demonstrated that IE patients had higher levels of antibodies to MUC-1, ER, and mammaglobin A compared to IN patients. MUC-1 expression was found to be higher in IE compared to IN breast tissue. RNA-seq analysis demonstrated upregulated pathways in IE breast tissue for B cell activation and development, Th2 related genes, T cell activation, chemotactic factors, and responses to estrogen. This is the first study to demonstrate that peri-implant inflammation extends beyond the implant capsule to breast parenchyma. Women with breast implants have more activated B cells in the breast parenchyma and elevated antibody responses to breast cancer antigen.

Single-cell analysis highlights differences in druggable pathways underlying adaptive or fibrotic kidney regeneration

The kidney has tremendous capacity to repair after acute injury, however, pathways guiding adaptive and fibrotic repair are poorly understood. We developed a model of adaptive and fibrotic kidney regeneration by titrating ischemic injury dose. We performed detailed biochemical and histological analysis and profiled transcriptomic changes at bulk and single-cell level (> 110,000 cells) over time. Our analysis highlights kidney proximal tubule cells as key susceptible cells to injury. Adaptive proximal tubule repair correlated with fatty acid oxidation and oxidative phosphorylation. We identify a specific maladaptive/profibrotic proximal tubule cluster after long ischemia, which expresses proinflammatory and profibrotic cytokines and myeloid cell chemotactic factors. Druggability analysis highlights pyroptosis/ferroptosis as vulnerable pathways in these profibrotic cells. Pharmacological targeting of pyroptosis/ferroptosis in vivo pushed cells towards adaptive repair and ameliorates fibrosis. In summary, our single-cell analysis defines key differences in adaptive and fibrotic repair and identifies druggable pathways for pharmacological intervention to prevent kidney fibrosis.

Prospects of cell chemotactic factors in bone and cartilage tissue engineering

Introduction Tissue engineering has brought hope for the repair of bone and cartilage injury. As potential therapeutic molecules for use in tissue engineering, chemokines promote the development of cell-free tissue engineering, avoiding dilemmas faced by cell-based tissue engineering. The main role of chemokines in tissue engineering is to recruit progenitor/stem cells to the site of damaged tissue in vivo and induce differentiation into the corresponding tissue, thus remodeling tissue function. In recent years, many studies have demonstrated the great potential of chemokines in the regeneration and repair of various tissues, such as heart, bone and cartilage tissue. Areas covered The classification, structure, and function of chemokines and the application of several common chemokines in diseases, especially in bone/cartilage tissue regeneration are discussed. Expert opinion Many experimental studies have demonstrated that the combinatory use of cell chemotactic factors (CCFs) and growth factors can exert synergistic effects on chondrogenesis and osteogenesis. With further understanding of biomaterials and the development of powerful bio-fabrication techniques, intelligent biomaterials will be created to meet the requirements for controlled bioactive factor release and biomimetic architecture. Also, a better understanding of the biological cascade reactions and pathways of CCFs is beneficial to guide the design of innovative biomaterials.

Production of Hematopoietic Stem Cell-Chemotactic Factor by Bone Marrow Stromal Cells

Chemotactic factors produced by stromal cells in the bone marrow are characterized. Two kinds of factors produced by stromal cell lines are identified using blind-well Boyden's Chambers; one is a neutrophil-chemotactic factor and the other a hematopoietic stem cell (HSC)-chemotactic factor. The latter attracts blastic cells in a low-density fraction, which are Thy1lo, wheat germ agglutinin (WGA)hi, H-2Khi, Ly-1-, Ly-2-, L3T4-, Ly5-, and slg-. The molecular weight of this HSC-chemotactic factor is estimated to be more than 200 kD. Putative cytokines and growth factors, such as granulocyte colony-stimulating factor (CSF), macrophage CSF, granulocyte-macrophage CSF, stem cell factor (SCF), interleukin (IL)-6, and IL-3, do not possess HSC-chemotactic activity. These findings strongly suggest that bone marrow stromal cells produce a new factor that attracts HSCs.

Increased circulating CXCL13 levels in systemic lupus erythematosus and rheumatoid arthritis: a meta-analysis.

CXC ligand 13 (CXCL13) is known as B cell chemotactic factor (BLC), promoting the migration of B lymphocytes by communicating with its receptor CXCR5, which can be regarded as part of pathogenesis of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). This meta-analysis was to evaluate the circulating CXCL13 levels in SLE and RA. All articles were respectively gathered from PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI) (by the end of 10 April 2019). According to random effects model, standardized mean difference (SMD) and 95% confidence interval (CI) of CXCL13 levels in SLE and RA were calculated by Stata 12.0 software. Totally, 15 studies were selected (981 SLE patients and 380 healthy controls, 332 RA patients and 147 healthy controls). SLE and RA patients were significantly increased in circulating CXCL13 levels (SMD = 1.851, 95% CI 0.604-3.098; SMD = 1.801, 95% CI = 1.145-2.457). Subgroup analyses showed that SLE patients from the Chinese group and systemic lupus erythematosus disease activity index (SLEDAI) score ≥ 6 group had higher circulating CXCL13 levels (SMD = 2.182, 95% CI 0.135-4.229; SMD = 0.767, 95% CI 0.503-1.030). However, there were no significant changes in CXCL13 concentrations in SLE patients from the English and SLEDAI score < 6 group. Similarly, subgroup analyses presented that RA patients from different classifications showed higher circulating CXCL13 levels. There was no publication bias. This meta-analysis demonstrated increased circulating CXCL13 concentrations in SLE and RA patients. Circulating CXCL13 levels may act as biomarkers and therapy targets in the diagnosis and treatment of SLE and RA.Key Point• First, CXC ligand 13 (CXCL13) is closely related to the pathogenesis of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), Second, this study may provide novel therapeutic targets for the treatment of SLE and RA patients. This meta-analysis provides a comprehensive analysis of circulating CXCL13 levels in patients with SLE and RA and also explores related influencing factors.

Does it make sense to target one tumor cell chemotactic factor or its receptor when several chemotactic axes are involved in metastasis of the same cancer?

The major problem with cancer progression and anti-cancer therapy is the inherent ability of cancer cells to migrate and establish distant metastases. This ability to metastasize correlates with the presence in a growing tumor of cells with a more malignant phenotype, which express certain cancer stem cell markers. The propensity of malignant cells to migrate and their resistance to radio-chemotherapy somewhat mimics the properties of normal developmentally early stem cells that migrate during organogenesis in the developing embryo. In the past, several factors, including cell migration-promoting cytokines, chemokines, growth factors, bioactive lipids, extracellular nucleotides, and even H+ ions, were found to influence the metastasis of cancer cells. This plethora of pro-migratory factors demonstrates the existence of significant redundancy in the chemoattractants for cancer cells. In spite of this obvious fact, significant research effort has been dedicated to demonstrating the crucial involvement of particular pro-metastatic factor–receptor axes and the development of new drugs targeting one receptor or one chemoattractant. Based on our own experience working with a model of metastatic rhabdomyosarcoma as well as the work of others, in this review we conclude that targeting a single receptor–ligand pro-metastatic axis will not effectively prevent metastasis and that we should seek other more effective therapeutic options.

Isopentenyl pyrophosphate secreted from Zoledronate-stimulated myeloma cells, activates the chemotaxis of γδT cells

γδT cell receptor (TCR)-positive T cells, which control the innate immune system, display anti-tumor immunity as well as other non-immune-mediated anti-cancer effects. γδT cells expanded ex vivo by nitrogen-containing bisphosphonate (N-BP) treatment can kill tumor cells. N-BP inhibits farnesyl pyrophosphate synthase in the mevalonate pathway, resulting in the accumulation of isopentenyl pyrophosphate (IPP), which is a stimulatory antigen for γδT cells. We have previously observed that as they get closer, migrating γδT cells increase in speed toward target multiple myeloma (MM) cells. In the present study, we investigated the γδT cell chemotactic factors involving using a micro total analysis system-based microfluidic cellular analysis device. The addition of supernatant from RPMI8226 MM cells treated with the N-BP zoledronic acid (ZOL) or the addition of IPP to the device induced chemotaxis of γδT cells and increased the speed of migration compared to controls. Analysis of the ZOL-treated RPMI8226 cell supernatant revealed that it contained IPP secreted in a ZOL-dose-dependent manner. These observations indicate that IPP activates the chemotaxis of γδT cells toward target MM cells treated with ZOL.

OTC Antioxidant Products for the Treatment of Cardiovascular and other Disorders: Popular Myth or Fact?

Cardiovascular disease (CVD) is the number one cause of mortality worldwide as reported by World Health Organization (WHO), Centers for Disease Control (CDC) and American Heart Association (AHA). The role of micronutrients has been studied extensively as CVD risk minimizing intervention. Among these, dietary supplements antioxidants available over the counter are highly commercialized but scientific evidences and clinical trials supporting their use is not conclusive yet [1]. The beneficial effects of these antioxidants are focused mainly against pathogenesis of atherosclerosis, as the primary contributor to coronary artery disease and resulting cardiovascular complications. Atherosclerosis is chronic inflammatory process of deposition of fatty cholesterol filled plaque in arterial wall which narrows the diameter and obstructs blood flow down the length of coronary artery and throughout its branches. Hyperlipidemia (high HDL: LDL ratio), high blood pressure, toxins from tobacco are assumed to be the major risk factor of atherosclerosis. If plasma LDL exceeds the regulatory capacity of endothelial cells, LDL crosses the endothelial barrier and trapped in sub-endothelial space where they are susceptible for oxidation by reactive oxygen species (ROS) - superoxide anion (·O2−), hydroxyl radical (OH·), hydrogen peroxide (H2O2), reactive nitrogen species (RNS), nitric oxide (NO) and peroxynitrite (ONOO·) released by endothelial cells and macrophages [2]. These modified LDL stimulates endothelial cells to express various cell adhesion molecules (VCAM-I, P-selectin etc.) and chemotactic factors (monocyte chemotactic factor-1, MCP-1) for the recruitment of monocytes. Monocyte attachment is initiated by P-selectin on endothelial cell upon binding with P-selectin glycoprotein ligand-1 (PSGL-1) on the monocytes leading to rolling and prolonging the contact of monocyte on the arterial wall and initiate diapedesis across endothelial layers. Monocytes differentiate into macrophages under the influence of monocyte colony stimulating factor (M-CSF). Oxidized LDL is then engulfed in an unregulated fashion by macrophage scavenger receptor resulting in intracellular accumulation of cholesterol and forms foam cell formation [3,4]. Macrophages are also involved in activation of T cells to amplify the inflammatory response by secreting TNF-α and INF-γ. Finally, smooth muscle cells proliferate and migrate from tunica media and shield the fatty plaque and synthesize collagen to form a fibrous cap [5–7].

Abstract WP94: Delayed SDF-1 Hyperexpression Promotes Neural Stem Cell Migration and Maturation without Increasing Inflammation after Ischemic Stroke in Mice

Background and purpose: SDF-1 has double-edged function after ischemic stroke. It can attract both inflammatory cells and neural stem cells (NSC). However, the action of SDF-1 in regulating neural stem cells migration and maturation during post-ischemic stroke is unclear. Here we used adeno-associated virus (AAV) to deliver SDF-1 gene into the peri-infarct area one week after permanent middle cerebral artery occlusion (MCAO) to investigate the effect of SDF-1 on endogenous NSC migration and maturation. Methods and materials: Twenty-four adult ICR male mice received AAV carrying SDF-1 or GFP gene transfer into the peri-infarct area one week after MCAO. Brain atrophy volume, neurobehavioral tests and immunohistochemistry were performed to evaluate the effects of SDF-1 on endogenous NSC migration, maturation and neuronal function repair. Results: SDF-1 was highly expressed in peri-infarct area for at least four weeks after gene transfer. Brain atrophy volume was significantly reduced in AAV-SDF-1 group compared to AAV-GFP gourp ( p &lt;0.05). The results of neurobehavioral tests including neurological deficits and rotarod test paralleled the result of atrophy volume, with neuronal function greatly improved in AAV-SDF-1 group ( p &lt;0.05). Immunohistology showed that the number of nestin and doublecortin positive cells in peri-infarct area was significantly increased in AAV-SDF-1 group in contrast to AAV-GFP group ( p &lt;0.05). In addition, there was no difference in myeloperoxidase positive cells in ischemic peri-infarct area between AAV-SDF-1 and AAV-GFP group ( p &gt;0.05). Conclusion: Our results demonstrated that SDF-1 gene therapy significantly increased NSC migration and maturation without increasing focal inflammatory response; consequently reduced brain atrophy volume and improved the neurological outcomes of animals, suggesting that delayed SDF-1 hyperexpression plays a key role in neurogenesis and neural repair. These in vivo results indicate that SDF-1 holds great potential as a stem cell chemotactic factor in the treatment of ischemic stroke.

Phenylbutyrate suppresses distinct skin reactions that are enhanced by blockade of epidermal growth factor receptor signaling

Epidermal growth factor receptor inhibitors (EGFRIs) cause skin inflammation, and understanding the factors that mediate this reaction is fundamental for designing therapies for EGFRI-related cutaneous side effects. We characterized EGFRI-enhanced skin reactions and evaluated the therapeutic efficacy of phenylbutyrate, a histone deacetylase inhibitor. PD168393, an EGFRI, was applied topically to the ear skin of mice with or without mast cell deficiency. The skin was then irritated once or pre-sensitized and repeatedly challenged with 2,4-dinitrofluorobenzene (DNFB). The reaction pattern, the type and number of infiltrating cells, changes in protein, cytokine (TNF-α) and chemokine (CCL2) expression, and the immune response were analyzed. Phenylbutyrate, formulated as a gel for topical treatment or dissolved in water for intraperitoneal administration, was tested as a treatment. EGFRI rapidly upregulated the mast cell chemotactic factor, stem cell factor (SCF) and augmented DNFB-induced immediate contact dermatitis within hours of treatment in the presence of mast cells. Topical phenylbutyrate treatment suppressed EGFRI-induced SCF expression in the epithelium, inhibited DNFB-induced mast cell recruitment in the dermis, and ameliorated the EGFRI-enhanced acute skin reaction. EGFRI also enhanced the delayed-type DNFB-induced hypersensitive reaction that was mast-cell independent but was associated with T lymphocytes. Systemic phenylbutyrate administration suppressed EGFRI-enhanced delayed-type skin hypersensitivity by increasing the number and function of Foxp3(+) T regulatory suppressor cells, which inhibited T helper cell proliferation. Our data suggest that phenylbutyrate has dual beneficial therapeutic effects on EGFRI-enhanced acute (local inflammatory) and late (systemic immune) skin reactions.

Oral tolerance inhibits pulmonary eosinophilia in a cockroach allergen induced model of asthma: a randomized laboratory study

BackgroundAntigen desensitization through oral tolerance is becoming an increasingly attractive treatment option for allergic diseases. However, the mechanism(s) by which tolerization is achieved remain poorly defined. In this study we endeavored to induce oral tolerance to cockroach allergen (CRA: a complex mixture of insect components) in order to ameliorate asthma-like, allergic pulmonary inflammation.MethodsWe compared the pulmonary inflammation of mice which had received four CRA feedings prior to intratracheal allergen sensitization and challenge to mice fed PBS on the same time course. Respiratory parameters were assessed by whole body unrestrained plethysmography and mechanical ventilation with forced oscillation. Bronchoalveolar lavage fluid (BAL) and lung homogenate (LH) were assessed for cytokines and chemokines by ELISA. BAL inflammatory cells were also collected and examined by light microscopy.ResultsCRA feeding prior to allergen sensitization and challenge led to a significant improvement in respiratory health. Airways hyperreactivity measured indirectly via enhanced pause (Penh) was meaningfully reduced in the CRA-fed mice compared to the PBS fed mice (2.3 ± 0.4 vs 3.9 ± 0.6; p = 0.03). Directly measured airways resistance confirmed this trend when comparing the CRA-fed to the PBS-fed animals (2.97 ± 0.98 vs 4.95 ± 1.41). This effect was not due to reduced traditional inflammatory cell chemotactic factors, Th2 or other cytokines and chemokines. The mechanism of improved respiratory health in the tolerized mice was due to significantly reduced eosinophil numbers in the bronchoalveolar lavage fluid (43300 ± 11445 vs 158786 ± 38908; p = 0.007) and eosinophil specific peroxidase activity in the lung homogenate (0.59 ± 0.13 vs 1.19 ± 0.19; p = 0.017). The decreased eosinophilia was likely the result of increased IL-10 in the lung homogenate of the tolerized mice (6320 ± 354 ng/mL vs 5190 ± 404 ng/mL, p = 0.02).ConclusionOur results show that oral tolerization to CRA can improve the respiratory health of experimental mice in a CRA-induced model of asthma-like pulmonary inflammation by reducing pulmonary eosinophilia.

The isolation of novel mesenchymal stromal cell chemotactic factors from the conditioned medium of tumor cells

Bone marrow-derived mesenchymal stromal cells (MSCs) localize to solid tumors. Defining the signaling mechanisms that regulate this process is important in understanding the role of MSCs in tumor growth. Using a combination of chromatography and electrospray tandem mass spectrometry we have identified novel soluble signaling molecules that induce MSC chemotaxis present in conditioned medium of the breast carcinoma cell line MDA-MB231. Previous work has employed survey strategies using ELISA assay to identify known chemokines that promote MSC chemotaxis. While these studies provide valuable insights into the intercellular signals that impact MSC behavior, many less well-described, but potentially important soluble signaling molecules could be overlooked using these methods. Through the less directed method of column chromatography we have identified novel candidate MSC chemotactic peptides. Two proteins, cyclophilin B and hepatoma-derived growth factor were then further characterized and shown to promote MSC chemotaxis.

Exploring the mast cell enigma: a personal reflection of what remains to be done

Mast cells are traditionally viewed as effector cells of allergic reactions and parasitic diseases, but their importance in host defense against bacteria, in tissue remodelling, their bone marrow and stem cell origin and a central role of the stem cell factor (SCF) as mast cell growth and chemotactic factor has been worked out only in recent years. Despite this, major aspects about the nature of the cells and their role in disease remain unclear. This holds in particular for the identification of mast cell precursors and the role of growth factors that stimulate specific mast cell commitment from stem cells, such as nerve growth factor, neutrotrophin-3 and certain interleukins, alone and during interaction with SCF. Early data suggesting also an involvement of specific transcription factors need to be expanded in this process. Furthermore, although mast cell proliferative disease (mastocytosis) has been shown to be often associated with SCF receptor c-kit mutations, reasons for the development of this disease remain unclear. This holds also for mast cell release mechanisms in many types of mast cell-dependent urticaria. Exciting new insights are emerging regarding the role of mast cells in bacterial infections, in defense against tumors, in wound healing and in the interplay with the nervous system, with hormones, and in the neurohormonal network. The aim of this reflection is to delineate the many known and unknown aspects of mast cells, with a special focus on their development, and to discuss in detail two mast cell-related diseases, namely mastocytosis and urticaria.

Plasmacytoid Dendritic Cells Induce Growth and Survival of Multiple Myeloma Cells: Therapeutic Application.

The bone marrow (BM) microenvironment confers growth, survival, and drug resistance in multiple myeloma (MM) cells. Here we have characterized the role of plasmacytoid dendritic cells (pDCs) in the MM BM milieu. Immunochemistry (IHC) analysis of tissue microarrays on MM patient BM biopsies with Abs specific against pDCs (CD123) and MM cells (CD138) shows pDCs in proximity of MM cells. Quantification of pDCs obtained by direct isolation from MM patient BM aspirates or peripheral blood (PB) showed increased numbers of pDCs in MM-BM compared to PB. Freshly isolated pDCs from normal healthy donors stimulate significant growth of MM cells: 4.1 ± 0.8 fold increase {3H}-thymidine uptake in MM cells co-cultured with pDCs versus control MM cells alone, (P < 0.005). Irradiated pDCs retain their ability to trigger proliferation of MM cells; furthermore, pDC-depleted PBMCs did not trigger significant growth of MM cells, confirming a specific MM cell growth-promoting activity of pDCs. Co-culture of patient MM cells with pDCs triggered a significant growth of tumor cells, but not normal BM-derived plasma cells. Importantly, both allogeneic and autologous MM-derived pDCs induced tumor cell growth. To determine whether pDCs enhance MM cell growth in vivo, mice were implanted subcutaneously with pDCs alone, MM cells alone or pDCs + MM cells, and tumor growth was monitored over 3 weeks. A robust growth of tumor in mice receiving pDC + MM occurred within 12 days, whereas mice injected with MM cell alone showed a similar tumor growth only at day 21. We further examined the ability of pDCs to prolong ex-vivo survival of patient MM cells. Co-culture of pDCs with patient MM cells significantly increased the survival of patient tumor cells (59%, n=5 P<0.05), and IHC analysis of pDCs-MM cells co-cultures at 4 weeks confirmed that MM cells are clonal. We next examined the effect of anti-MM agents bortezomib and dexamethasone on the viability of pDCs and pDC-induced MM cell growth. Treatment of pDCs with bortezomib (20 nM) or dexamethasone (500 nM) does not significantly decrease viability of these cells (P = 0.25), higher concentrations of bortezomib (50 and 100 nM) decrease the viability of pDCs by less than 10%. Importantly, proliferation assays confirmed that pDCs triggered MM cell growth even in the presence of bortezomib, albeit to a lesser extent than without bortezomib(P<0.05). Microarray analysis showed that the pDCs-MM cells interaction triggered significant changes in transcriptional activity of genes related to growth, survival, anti-apoptosis, and migration in MM cells. Cytokine bead array analysis of supernatants from pDCs-MM cells co-cultures showed a marked increase in the secretion of MM cell growth, survival and chemotactic factors, such as IL-10, IL-6, IL-8, TNF-α, IL-1Rα, IL-1α, IL-13, IL-15, CD40L, MCP-1, MIP-1β, IP10 and VEGF. Overall, our data therefore show that pDCs predominantly localize in the MM BM and functionally interact with MM cells via cell-cell contact and subsequent cytokine secretion, allowing for MM cell growth and survival even in the presence of conventional and novel drugs. These studies will provide the basis for novel therapeutic approaches targeting pDC-MM interaction to improve patient outcome in MM.

The H1 histamine receptor regulates allergic lung responses

Histamine, signaling via the type 1 receptor (H1R), has been shown to suppress Th2 cytokine production by in vitro cultured T cells. We examined the role of H1R in allergic inflammation in vivo using a murine asthma model. Allergen-stimulated splenic T cells from sensitized H1R-/- mice exhibited enhanced Th2 cytokine production. Despite this Th2 bias, allergen-challenged H1R-/- mice exhibited diminished lung Th2 cytokine mRNA levels, airway inflammation, goblet cell metaplasia, and airway hyperresponsiveness (AHR). Restoration of pulmonary Th2 cytokines in H1R-/- mice by intranasal IL-4 or IL-13 restored inflammatory lung responses and AHR. Further investigation revealed that histamine acts as a T cell chemotactic factor and defective T cell trafficking was responsible for the absence of lung inflammation. Cultured T cells migrated in response to histamine in vitro, but this was ablated by blockade of H1R but not H2R. In vivo, allergen-specific WT but not H1R-/- CD4+ T cells were recruited to the lungs of naive recipients following inhaled allergen challenge. H1R-/- T cells failed to confer airway inflammation or AHR observed after transfer of WT T cells. Our data establish a role for histamine and H1R in promoting the migration of Th2 cells into sites of allergen exposure.

Enhanced cell surface CD44 variant (v6, v9) expression by osteopontin in breast cancer epithelial cells facilitates tumor cell migration: Novel post-transcriptional, post-translational regulation

Osteopontin (OPN) is a glycosylated, secreted phosphoprotein that functions both as a cell attachment and chemotactic factor. Elevated expression of OPN confers enhanced metastatic ability on transformed cells, suggesting that OPN may contribute to the malignant progression of tumors. Migration of mammary carcinoma cells is stimulated by OPN via interactions with integrins and CD44 cell surface receptors. We hypothesized that OPN modulates specific CD44 isoform expression to facilitate breast cancer cell migration. The 21NT tumorigenic human breast cancer cell line was examined for regulation of CD44 expression at both the mRNA and protein levels in response to an engineered increase in OPN expression under CMV promoter control. Significant up-regulation of CD44s isoform mRNA expression was observed, but no change in CD44v6, v8, v9 or v10 mRNA levels. While there were elevated levels of CD44s, v6 and v9 protein at the cell surface, at the level of total cellular protein only CD44s and v6 were markedly increased. This suggests that OPN can regulate CD44 expression at both transcriptional and post-transcriptional (both amount and localization of protein) levels. To validate the functional consequence of OPN regulation of CD44 expression, we demonstrate that OPN-mediated cell migration was reduced by exposure to a anti-pan CD44 antibody, and to anti-CD44v6 and anti-CD44v9 function-blocking antibodies. Our data provide evidence that in 21NT cells OPN enhances CD44s mRNA expression, increases cell surface expression of CD44 variant forms without a change in mRNA levels, and stimulates cell migration.

Simian Human Immunodeficiency Virus-Associated Pneumonia Correlates with Increased Expression of MCP-1, CXCL10, and Viral RNA in the Lungs of Rhesus Macaques

Pulmonary disorders are the most frequent cause of death in HIV-1-infected individuals with AIDS and remain important even in the current era of potent antiretroviral therapy. Macaques infected with Simian/Human Immunodeficiency Virus (SHIV) develop pulmonary disease and concurrent opportunistic infections similar to those observed in HIV-infected individuals, thereby providing an excellent working model to elucidate the pathogenesis of the human lung disease. Since chemokines play a crucial role in the recruitment of inflammatory cells to tissues, we investigated the relationship between respiratory disease and the levels of chemokines, monocyte chemotactic protein-1 (MCP-1) and CXCL10, in the lungs of SHIV-infected rhesus macaques. We found that lung pathology in infected macaques was closely associated with overexpression of MCP-1 and CXCL10. In addition, these chemokines could, in part, be responsible for the recruitment of inflammatory cells infiltrating into the diseased lungs as demonstrated by chemotactic assays. Lung pathology and increased levels of MCP-1 and CXCL10 correlated with high viral loads in the lung parenchyma. Using confocal microscopy, we identified SHIV-infected macrophages as the major producers of MCP-1 and CXCL10 in the diseased lungs. These data suggest that chemokine overexpression plays an important role in the pathogenesis of SHIV-associated pulmonary disease in macaques.

IL-16 Activates Plasminogen-Plasmin System and Promotes Human Eosinophil Migration into Extracellular Matrix via CCR3-Chemokine-Mediated Signaling and by Modulating CD4 Eosinophil Expression

Increased eosinophil counts are a major feature of asthmatic airways. Eosinophil recruitment requires migration through epithelium and tissue extracellular matrix by activation of proteases. We assessed the capacity of IL-16, a CD4(+) cell chemotactic factor, to induce migration of eosinophils through a reconstituted basement membrane and evaluated the proteases, mediators, and receptors involved in this migration. IL-16 added to lower chambers of Invasion Chambers elicited eosinophil migration through Matrigel. This effect was decreased by inhibition of the plasminogen-plasmin system (Abs against urokinase plasminogen activator receptor or plasminogen depletion), but not by anti-matrix metalloproteinase-9 Abs. Abs against CD4 also inhibited IL-16-induced eosinophil migration. At the baseline level, few eosinophils (4.6% positive cells with a mean fluorescence of 0.9) expressed surface membrane CD4, while most permeabilized eosinophils (68% positive cells with a mean fluorescence of 18) express the CD4 Ag. TNF-pretreatment increased surface membrane CD4(+) expression by 6-fold as previously described, and increased IL-16-induced cell migration by 2.2-fold. Incubation of eosinophils with IL-16 also increased surface membrane CD4 expression by 5.4-fold, supporting the role of CD4 as receptor for IL-16. Abs against CCR3, eotaxin, or RANTES blocked IL-16-induced migration. In conclusion, IL-16 promotes eosinophil migration in vitro, by activating the plasminogen-plasmin system and increasing the membrane expression of its receptor. This effect is initiated via CD4 and mediated via the release of CCR3 ligand chemokines. Interestingly, most eosinophils express intracellular CD4. Hence, IL-16 may play an important role in the recruitment of blood eosinophils to the bronchial mucosa of asthmatics.

Cardiac mast cells in the transition to heart failure

Cardiac mast cells in the transition to heart failure

In vitro demonstration of breast cancer tumor cell sub-populations based on interleukin-1/tumor necrosis factor induction of interleukin-8 expression

Interleukin-8 (IL-8) has been identified as an angiogenesis factor (AF) as well as a tumor cell chemotactic factor and mitogen. Recent in vivo studies have demonstrated the expression of IL-8, IL-1 and TNF, as well their receptors, on various sub-populations of tumor cells in human breast cancer (HBC). Since pro-inflammatory cytokines such as IL-1 and TNF are known inducers of IL-8 in non-tumor cells, we hypothesize that IL-1/TNF may act as an IL-8 inducer in HBC, and thus enhance HBC tumor progression. To begin to test this hypothesis, we evaluated the ability of: a) human breast cancer cell lines (BCC) and normal human breast epithelial cell lines (BEC) to produce IL-8 in vitro; and b) IL-1 and TNF to regulate the expression of IL-8. In general, basal IL-8 expression was low in all 8 cell lines examined. TNF-alpha and TNF-beta induced a 3- to 24-fold increase in IL-8 protein expression of BEC, and a 2- to 8-fold increased IL-8 expression in estrogen-independent BCC cell lines and no significant IL-8 expression in estrogen-dependent cell lines. Conversely, IL-1alpha and IL-1beta, induced a 5- to 104-fold stimulation of BEC and a 330 to 1,138-fold increase in IL-8 expression in estrogen independent BCC. These observations demonstrate the ability of HBC cells to produce IL-8 in vitro and further indicate that IL-1 is a potent inducer of IL-8 expression by BEC and BCC. Furthermore, this in vitro data support the hypothesis, that within the HBC tumor microenvironment, tumor cells exist that respond to pro-inflammatory cytokine (IL-1) stimulation (i.e. MDA-MB-231) and those that do not (i.e. MCF-7). Additionally, HBC tumor cell lines that can be induced to express high levels of IL-8 tend to be associated with a more aggressive phenotype.