Intercellular cell adhesion molecule-1, vascular cell adhesion molecule-1, and regulated on activation normal T cell expressed and secreted are expressed by human breast carcinoma cells and support eosinophil adhesion and activation

Eosinophils are usually associated with parasitic and allergic diseases; however, eosinophilia is also observed in several types of human tumors, including breast carcinomas. In this study we examined several human breast carcinoma cell lines for adhesion molecule expression and the ability to bind and activate eosinophils. MDA-MB-435S and MDA-MB-468 cells constitutively expressed both intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and this expression was enhanced by treatment with tumor necrosis factor-alpha (TNF-alpha). BT-20 and SK-BR-3 cells only expressed ICAM-1 or VCAM-1 after stimulation with TNF-alpha. Eosinophils constitutively bound to MDA-MB-435S cells, but not to BT-20 cells. Stimulation with TNF-alpha slightly enhanced eosinophil adhesion to MDA-MB-435S cells and dramatically increased adhesion to BT-20 cells. Greater than 80% of eosinophil adhesion to these cell lines was blocked with an anti-alpha4-integrin monoclonal antibody. Both MDA-MB-435S and BT-20 cells also released eosinophil activator(s). Supernatants from TNF-alpha-treated, but not control-treated, cell lines increased eosinophil adhesion to fibronectin and increased eosinophil transmigration across fibronectin-coated transwell plates. Enzyme-linked immunosorbent assays showed that TNF-alpha-stimulated breast carcinoma cells released the chemokine regulated on activation, T cell expressed and secreted (RANTES). Addition of an anti-RANTES antibody to breast carcinoma cell supernatants partially blocked eosinophil activation suggesting that RANTES in these supernatants was participating in eosinophil activation. These data show that TNF-alpha-stimulated breast carcinoma cells express mediators that can both bind and activate eosinophils, suggesting a mechanism for eosinophil localization to breast carcinoma sites.     

Respiratory syncytial virus infection of human primary nasal and bronchial epithelial cell cultures and bronchoalveolar macrophages.

In adults, clinical symptoms caused by respiratory syncytial virus (RSV) are usually confined to the upper respiratory tract, whereas RSV infection in infants frequently causes bronchiolitis and pneumonia. The preferential localization of RSV infection to the upper airways may partially be due to protective immunity, but may also depend on a difference in susceptibility of epithelial cells from upper and lower airways, or on antiviral activities of bronchoalveolar macrophages (AM). In this study, we have compared the susceptibility of primary adult human nasal epithelium, primary adult human bronchial epithelium, a human bronchial epithelial cell line (BEAS-2B), and adult human AM to infection with RSV. The cell cultures were infected with multiplicities of infection (moi) of 1 and 0.1. Virus release into the supernatants was assayed at days 1, 2, 4, and 7, and the percentage of virus-positive cells determined by immunofluorescence at the same time points. Similar proportions of nasal epithelial cells (NE) and bronchial epithelial cells (BE) were infected with RSV. Approximately 50 to 75% (with moi 1) and 2 to 10% (with moi 0.1) of the cells were infected by 24 h; almost all the cells were RSV positive by day 4. However, BE released less infectious RSV than do NE. With moi 0.1, 10-fold less virus was released over 4 days of culture. By days 4 to 7, cytopathic effects (CPE) were maximal in all epithelial cell cultures, but CPE developed latest in BE infected with moi 0.1. AM were also productively infected with RSV, with peak virus production at day 2.(ABSTRACT TRUNCATED AT 250 WORDS)     

IgE anti-respiratory syncytial virus antibodies detected in serum of pediatric patients with asthma

Respiratory syncytial virus (RSV) causes lower respiratory tract disease in infants and young children, and is a public health concern, as is the increase in pediatric asthma. Respiratory viral infections may trigger asthma exacerbations. However, it remains unknown whether RSV infection may have a specific association with asthma. Total serum IgE, and IgE- and IgG-anti-RSV Ab responses were studied in older asthmatic compared with non-asthmatic children (M/F, mean age: 14) (N = 30, N = 43, respectively). We found: (1) total serum IgE was higher in asthmatic compared with non-asthmatics (P < 0.001); (2) total serum IgE did correlate with IgE anti-RSV Abs (P < 0.001), and with IgG anti-RSV Abs (P = 0.008) in all subjects; (3) total serum IgE levels did correlate with IgE anti-RSV in asthmatics (P = 0.047), but not in non-asthmatics (P = 0.13); (4) IgE anti-RSV Abs did correlate with IgG anti-RSV Abs in all subjects (P = 0.001); (5) IgE- and IgG-anti RSV Abs were higher in asthma compared with no asthma (P = 0.003; <0.001, respectively); (6) there was a significant association between age and IgE anti-RSV in non-asthma (P = 0.008), but not in asthma (P = 0.64). Our findings indicate that IgE-anti-RSV Ab responses may play important roles in RSV infection and asthma.     

The role of the C-C chemokine receptor-5 Delta32 polymorphism in asthma and in the production of regulated on activation, normal T cells expressed and secreted.

BACKGROUND: There are conflicting data regarding the role of a deletion in the C-C chemokine receptor-5 gene (CCR5*D32) in the pathogenesis of asthma and whether this deletion influences the production of regulated on activation, normal T cells expressed and secreted (RANTES). RANTES is a chemokine that is known to play an important role in the pathogenesis of allergic asthma. OBJECTIVE: We sought to determine whether CCR5*D32 is associated with increased RANTES production, the presence of asthma, and the severity of asthma. METHODS: A PCR assay for CCR5*D32 was developed. The prevalence of CCR5*D32 was determined in a group of patients with mild-to-moderate asthma, a group of subjects with severe asthma who had fatal or near-fatal asthma attacks, and a group of nonasthmatic control subjects. The level of RANTES produced by stimulated and unstimulated T cells was measured by using a commercially available immunoassay. RESULTS: The frequency of CCR5*D32 was not significantly increased in the severe asthma group compared with in the mild-to-moderate asthma group. CCR5*D32 was not increased in the asthmatic subjects versus in the control subjects. There was no significant increase in RANTES levels from T cells heterozygous for CCR5*D32 compared with wild-type cells. CONCLUSION: These data indicate that the CCR5*D32 allele is not a genetic risk factor for the development of asthma and does not influence disease severity. The CCR5*D32 allele does not influence RANTES production in the heterozygous state.     

受激活调节正常T细胞表达和分泌因子及其受体CCR1、CCR5在大鼠附睾的表达与定位

目的:观察受激活调节正常T细胞表达和分泌因子(RANTES)与其受体CCR1、CCR5在大鼠附睾中的表达和定位.方法:采用免疫组织化学法检测成年大鼠附睾上皮RANTES及其受体的细胞定位,免疫荧光双标染色分别显示RANTES与CCR1、CCR5的细胞共定位情况.RT-PCR检测RANTES及其受体mRNA表达水平,免疫印迹检测RANTES及其受体的蛋白量.结果:RANTES与其受体CCR1、CCR5在大鼠附睾各段呈特异性表达.免疫印迹在大鼠附睾各段检测到RANTES及其受体CCR1、CCR5特异性蛋白条带.RANTES与其受体CCR1、CCR5在大鼠附睾上皮主要表达于基细胞.双重免疫荧光显示RANTES与CCR1、CCR5在附睾管基细胞共存.结论:RANTES可能通过自分泌或(和)旁分泌方式在大鼠附睾基细胞功能活动方面起重要作用.     

Defining the levels of secreted non-structural protein NS1 after West Nile virus infection in cell culture and mice

Infection with West Nile virus (WNV) causes a febrile illness that can progress to meningitis or encephalitis, primarily in humans that are immunocompromised or elderly. For successful treatment of WNV infection, accurate and timely diagnosis is essential. Previous studies have suggested that the flavivirus non-structural protein NS1, a highly conserved and secreted glycoprotein, is a candidate protein for rapid diagnosis. Herein, we developed a capture enzyme-linked immunosorbent assay (ELISA) to detect WNV NS1 using two anti-NS1 monoclonal antibodies (mAbs) that map to distinct sites on the protein. The capture ELISA efficiently detected as little as 0.5 ng/ml of soluble NS1 and exhibited no cross-reactivity for yellow fever, Dengue, and St. Louis encephalitis virus NS1. The capture ELISA reliably detected NS1 in plasma at day 3 after WNV infection, prior to the development of clinical signs of disease. As the time course of infection continued, the levels of detectable NS1 diminished, presumably because of interference by newly generated anti-NS1 antibodies. Indeed, treatment of plasma with a solution that dissociated NS1 immune complexes extended the window of detection. Overall, the NS1-based capture ELISA is a sensitive readout of infection and could be an important tool for diagnosis or screening small molecule inhibitors of WNV infection.     

Respiratory syncytial virus infection in children with severe motor and intellectual disabilities

Children with severe motor intellectual disabilities (SMID) are at high risk of death from acute viral lower respiratory tract infections (LRTI). Although respiratory syncytial virus (RSV) is the most common cause of viral LRTI in children, there have been a few reports on the relationship between SMID and the severity of RSV-LRTI. The aim of the present study is to assess the influence of RSV-LRTI in children with SMID. A case–control study composed of children with SMID (n?=?18) and previously healthy children (n?=?43) less than 16 years old hospitalized for RSV-LRTI was performed during five consecutive RSV seasons. The clinical presentation and the laboratory data in the SMID group were compared with those in the non-SMID group. In the bivariate analysis, the median age of the SMID group was higher than that of the non-SMID group (p?=?0.002). Children with SMID had an increased risk for ventilation support (p?=?0.057). The count of neutrophils in the SMID group was significantly increased (p?=?0.012), whereas the proportion of bacterial co-infection was lower than that in the non-SMID group (p?=?0.005). Multivariate logistic analysis showed that SMID was associated with longer oxygen usage [>7 days: odds ratio (OR) 5.309, p?=?0.033]. The present study revealed that children with SMID were prone to developing hypoxia by RSV-LRTI. The strategies for the treatment and prevention of RSV infection need to be improved in SMID children.     

Changes in serum and ascitic monocyte chemotactic protein-1 (MCP-1) and IL-10 levels in cirrhotic patients with spontaneous bacterial peritonitis.

Spontaneous bacterial peritonitis (SBP) is a prototypical infectious disease of cirrhotic patients. It has been suggested that cirrhotic patients' response to infection is less effective because of differences in the inflammatory and immune reactions. This study aimed to investigate the expression of the inflammatory cytokines monocyte chemotactic protein-1 (MCP-1) and interleukin-10 (IL-10) in cirrhotic patients with SBP. The MCP1 and IL-10 levels in the sera and ascitic fluids of cirrhotic patients with (n = 40) or without SBP (n=17) were serially analyzed by ELISA. In the non-SBP group, the mean MCP-1 levels in sera and ascites were 53.0 +/- 45.8 pg/mL and 197.5 +/- 109.5 pg/mL, respectively, and the IL-10 levels were 10.9 +/- 9.5 pg/mL and 77.6 +/- 79.7 pg/mL, respectively. In the SBP group, the mean MCP-1 levels in serum and ascites before treatment were 164.7 +/- 126.4 pg/mL and 365.3 +/- 583.0 pg/mL, respectively, and the IL-10 levels were 31.4 +/- 44.1 pg/mL and 188.1 +/- 189.5 pg/mL, respectively. The sera MCP-1 and ascites IL-10 levels differed significantly between the two groups. In the SBP group, sera and ascitic MCP-1 and IL-10 levels fell during treatment. The low MCP-1 and IL-10 levels on the seventh day of treatment were found to have a statistically significant relationship to patient survival. MCP-1 and IL-10 levels in sera and ascites may be related to the clinical course of SBP.     

Respiratory syncytial virus recombinant F protein (residues 255-278) induces a helper T cell type 1 immune response in mice

We have developed and evaluated an immunodominant respiratory syncytial virus (RSV) F antigen in a mouse model. The antigenic region corresponding to amino acids 255-278 of the RSV F protein was cloned into a vector containing the ctxA(2)B gene of cholera toxin (CT). The recombinant protein was expressed in Escherichia coli and analyzed on sodium dodecyl sulfate-polyacrylamide gels. The purified protein was evaluated by immunoblot and ganglioside GM(1) enzyme-linked immunosorbent assay to confirm the expression of the RSV F protein and to correct association of the recombinant protein to form a holotoxin-like chimera, respectively. We hypothesized that genetic fusion of modified CT-based adjuvant with RSV F immunodominant epitopes (rRF-255) would induce protective humoral and cellular immune responses in mice. Intranasal immunization of mice with rRF-255 overall induced higher concentrations of anti-RSV F-specific antibodies in both serum and saliva as compared with mice immunized intranasally with RSV or phosphate-buffered saline (PBS). Antibody isotype analysis (IgA, IgG1, IgG2a, and IgG2b) was also performed. The predominant IgG2a antibody isotype response in combination with cytokine analysis of helper T cell type 1 (interferon-gamma, interleukin [IL]-2, IL-12 p70, and tumor necrosis factor-alpha) and helper T cell type 2 (IL-4 and IL-10) responses revealed that rRF-255 antigen induces a prominent helper T cell type 1 immune response in mice. The rRF-255 antigen also induced serum neutralizing antibodies in immunized mice. Analysis of RSV load in lungs showed that rRF-255 immunization provided significant protection compared with PBS control animals.     

Differential effects of Chlamydia pneumoniae infection on cytokine levels in human T lymphocyte- and monocyte-derived cell cultures

Continuous cultures of human lymphocyte- and monocyte-derived cell lines were examined for levels of immunoregulatory cytokines important in resistance to the intracellular opportunistic bacterium Chlamydia pneumoniae (Cp), a ubiquitous pathogen widely disseminated in the population and hypothesized to be involved in chronic inflammatory diseases such as atherosclerosis and neurological diseases like multiple sclerosis and Alzheimer's disease. The results of this study showed that the continuous human T lymphocyte cell line MOLT-4 and the continuous monocytic cell line THP-1 were readily infected by Cp in vitro as shown by immunofluorescence microscopy for Cp lipopolysaccharide (LPS). The 16S rRNA expression determined by real-time RT-PCR increased rapidly after infection of either cell line with these bacteria. The THP-1 cells infected with Cp showed increased levels of the immunoregulatory cytokine IL-12 and also of TNFalpha and IL-10 compared to cultures stimulated with heat-killed Cp (KCp) or Escherichia coli LPS as a control. Stimulation of MOLT-4 cells with KCp or E. coli LPS also induced the Th1 cytokines IFNgamma and IL-12 and the Th2 cytokine IL-10, but infection with viable Cp induced higher Th1 cytokine levels. These results suggest that Cp infection induces a predominant Th1 cytokine profile by T cells, in addition to induction of TNFalpha by monocytes/macrophages. Such effects are likely involved in antibacterial immunity against Cp infection.     

Association between serum-soluble CD8 levels and parameters of immune activation in patients with human immunodeficiency virus infection

Summary We compared the serum concentrations of soluble CD8 with the immune activation markers neopterin, interferon-, tumour necrosis factor-, soluble CD4, and with CD34⁺ and CD38⁺ T-cell counts in patients with human immunodeficiency virus (HIV) infection. The majority of patients had increased concentrations of soluble CD8, interferon- and neopterin, and various significant correlations existed between them. Our results support the view that enhanced soluble CD8 levels indicate activated CD8⁺ T cells in patients with HIV infection.Abbreviations sCD8 serum-soluble CD8 - sCD4 serum-soluble CD4 - IFN- interferon- - TNF =tumour necrosis factor- - HIV human immunodeficiency virus - AIDS acquired immunodeficiency virus     

In vivo expression of interleukin-8, and regulated on activation, normal, T-cell expressed, and secreted, by human germinal centre B lymphocytes

T-cell homing within germinal centres (GCs) is required for humoral B-cell responses. However, the mechanisms implicated in the recruitment of T cells into the GC are not completely understood. Here we show, by immunohistology, and Northern and Western blots, that in vivo human GC B lymphocytes can express CxC and CC chemokines. Moreover, B-cell subset-specific experiments reveal that interleukin (IL)-8 and regulated on activation, normal, T-cell expressed, and secreted (RANTES) are predominantly expressed by GC centroblast and centrocytes, suggesting that chemokine expression is essential at stages in which B-lymphocytes engage in active antigen-dependent interactions with T lymphocytes. In keeping with this hypothesis, we show that the T cells recruited into the GC correlatively express the receptors for IL-8 and RANTES. We propose that chemokine expression is a key B-cell function that facilitates T-lymphocyte recruitment into the GCs and supports cognate B-cell : T-cell encounters. Moreover, our data are consistent with the impaired homing of T cells to secondary lymphoid organs in mice that are either deficient in CC and CxC chemokines or their receptors.     

Transient high levels of viremia in patients with primary human immunodeficiency virus type 1 infection.

BACKGROUND. The rapidly evolving clinical picture of primary infection with the human immunodeficiency virus type 1 (HIV-1) suggests that a better understanding of the kinetics of viral replication in vivo during the short period before seroconversion may provide insight into the pathogenesis of the acquired immunodeficiency syndrome (AIDS). METHODS AND RESULTS. Titers of infectious HIV-1 were determined by end-point-dilution culture in sequential samples of plasma and peripheral-blood mononuclear cells from four patients with primary infection, with peak titers of 1000 to 10,000 tissue-culture-infective doses per milliliter of plasma and 100 to 10,000 infective doses per 10(6) peripheral-blood mononuclear cells. The high viral burden in mononuclear cells was confirmed by quantitative studies using a polymerase-chain-reaction method. In as little as 10 days, the high HIV-1 load in both plasma and cells decreased spontaneously and precipitously, at least 100-fold, in all four patients. CONCLUSIONS. Although p24 core antigenemia and viral isolation have previously been described during primary HIV-1 infection, this report documents the large viral burden during the acute phase of infection. The rapid and spontaneous decline in the viral load suggests an effective immune response in the host that, if understood, may be used to combat AIDS.     

Frequency of gC1qRCD4 T cells increases during acute hepatitis C virus infection and remains elevated in patients with chronic infection

CD4⁺ T cell responses are impaired in chronic HCV infection. To determine factor(s) involved in CD4⁺ T cell dysregulation, we examined the effect of extracellular core on the alteration of CD4⁺ T cell responses and the cell surface level of core-binding protein, gC1qR on CD4⁺ T cells from acute HCV patients with resolved and chronic infection. During the acute phase of infection, the frequency of gC1qR⁺CD4⁺ T cells increased in both resolved and chronic HCV infection compared to healthy controls. Notably, 6 months later, the frequency of gC1qR⁺CD4⁺ T cells maintained elevated in chronic patients compared to that in resolved patients. In addition, TCR stimulation increased the frequency of gC1qR⁺CD4⁺ T cells, resulting in core-induced inhibition of T cell responses in both resolved and chronic patients. These results suggest that HCV infection expands gC1qR⁺CD4⁺ T cells, which increase the susceptibility to core-mediated immune dysregulation and facilitate the establishment of HCV persistency.     

Homotypic cell-cell adhesion induced by human T cell leukemia virus type 1 tax protein in T cell lines

Cell-cell adhesion is involved in the processes of cell growth, activation and migration, and inflammation. T cells infected with human T cell leukemia virus type 1 (HTLV-1) exhibit a high degree of homotypic cell-cell adhesion in vitro. In this study, we investigated the involvement of the viral protein Tax in such process. Expression of Tax in an interleukin (IL)-2-dependent mouse T cell line (CTLL-2) increased homotypic cell-cell adhesion; however, less cell adhesion was induced by Tax than that observed in HTLV-1-infected T cell lines. Moreover, Tax induced cell-cell adhesion in a human T cell line, in which the expression of Tax is inducible. Microscopic examination also revealed Tax-induced morphologic changes, including rounding of CTLL-2 cells, increased cell volume, and increased nucleus size. Taken together, our results suggest that Tax induces cell-cell adhesion and morphologic changes in HTLV-1-infected cells. Tax may thus play a role in persistent HTLV-1 infection and the pathogenesis of associated disease.     

Red blood cell deformability in patients with human immunodeficiency virus infection

Red blood cell (RBC) deformability is a major determinant of the ability of the RBC to pass repeatedly through the microcirculation. A decrease in RBC deformability leads to tissue perfusion and organ dysfunction. The purpose of this study was to measure the rigidity of RBCs from human immunodeficiency virus (HIV) seropositive individuals and investigate its relation to immune status and viral load. A filtration method based on the initial flow rate principle was used to determine the index of rigidity (IR) of 53 samples from HIV patients and 53 healthy individuals. The mean IR was significantly increased in patients with HIV compared to healthy individuals (P < 0.01). IR was inversely correlated with current CD4+ T-lymphocyte counts (P < 0.0001). High CD4 cell counts (>200cells/μl) are related to low IR values, independently of the viral load (VL). No differences in rigidity were noted between the VL groups, although there was a trend towards an increased IR in patients with high VL within the group of CD4<200. RBC deformability is decreased in HIV disease, in a degree mainly related to CD4 depletion. Further studies are needed to elucidate the underlying mechanisms and the role of VL in highly immunocompromised HIV patients.     

Bronchial hyperreactivity to histamine and levels of serum eosinophil cationic protein in patients with non-atopic asthma

Pathogenesis of non-atopic bronchial asthma remains still an open question. Until now there have been very few studies concerning relationship between eosinophil activation and nonspecific bronchial hyperreactivity to histamine in this form of asthma. Sixteen subjects with mild nonatopic bronchial asthma entered the study. Evaluations of PC 20 for histamine and serum eosinophil cationic protein (ECP) concentration have been performed in all patients. In spite of fact that all patients were considered as mild asthmatic we have observed wide range of PC 20 and serum ECP concentration. Moreover we were able to find statistically significant inverse correlation between PC 20 for histamine and serum eosinophil cationic protein concentration: r = -0.498, p < 0.05. We conclude that eosinophil activation plays an important role in pathophysiology of nonspecific bronchial hyperreactivity in nonatopic bronchial asthma.