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1.
Pertussis toxin (PT) and filamentous hemagglutinin (FHA) are two major virulence factors of Bordetella pertussis. FHA is the main adhesin, whereas PT is a toxin with an A-B structure, in which the A protomer expresses ADP-ribosyltransferase activity and the B moiety is responsible for binding to the target cells. Here, we show redundancy of FHA and PT during infection. Whereas PT-deficient and FHA-deficient mutants colonized the mouse respiratory tract nearly as efficiently as did the isogenic parent strain, a mutant deficient for both factors colonized substantially less well. This was not due to redundant functions of PT and FHA as adhesins, since in vitro studies of epithelial cells and macrophages indicated that FHA, but not PT, acts as an adhesin. An FHA-deficient B. pertussis strain producing enzymatically inactive PT colonized as poorly as did the FHA-deficient, PT-deficient strain, indicating that the ADP-ribosyltransferase activity of PT is required for redundancy with FHA. Only strains producing active PT induced a local transient release of tumor necrosis factor alpha (TNF-alpha), suggesting that the pharmacological effects of PT are the basis of the redundancy with FHA, through the release of TNF-alpha. This may lead to damage of the pulmonary epithelium, allowing the bacteria to colonize even in the absence of FHA.  相似文献   

2.
Quantitation of cytokine production is a valuable adjunct to standard immunologic assays in defining several pathologic processes. Nevertheless, there is little agreement about which tissues should be assayed, which type of assay should be performed, and which stimulation protocol should be used. As these types of assays enter the clinical arena, there is need for standardization. There is also a need to maximize the amount of information which may be derived from a single sample. We compared secreted interleukin 4 (IL-4), IL-2, IL-6, tumor necrosis factor alpha (TNF-α), and gamma interferon proteins as measured by enzyme-linked immunosorbent assay with intracellular cytokine production (IL-2 and gamma interferon) as detected by flow cytometry and quantitative competitive PCR for IL-2, IL-4, TNF-α, and gamma interferon mRNA and cDNA. Results from unstimulated cells and cells stimulated with phorbol myristate acetate, phytohemagglutinin, and phorbol myristate acetate plus phytohemagglutin were compared. All three methodologies detected significant stimulation of cytokine production. The combination of phytohemagglutinin and phorbol myristate acetate was overall the most-potent stimulus.  相似文献   

3.
The kinetic profile of cytokine gene expression in normal human peripheral mononuclear cells (MNC) activated by an anti-CD3 monoclonal antibody was studied. The presence or absence of 10 different cytokine mRNA were measured in a polymerase chain reaction (PCR) assisted mRNA amplification assay. After 2 h of stimulation the mRNA for interleukin-1 alpha (IL-1 alpha), interleukin-2 (IL-2), interleukin-3 (IL-3), tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) were detectable and remained present during the whole time period studied (22 h). Interleukin-6 (IL-6) and granulocyte macrophage colony stimulating factor (GM-CSF) were detected after 4 h, while interleukin-10 (IL-10) mRNA did not appear until after 7 h; they all remained expressed at 22 h. A transient expression of interleukin-4 (IL-4) mRNA was observed between 4 and 7 h of stimulation. No gene expression of granulocyte colony stimulating factor (G-CSF) was detected at any time. These results show that anti-CD3 stimulation of MNC leads to a rapid sequential induction of different cytokine mRNA, some with a very transient expression.  相似文献   

4.
The aim of this study was to verify the role played by mononuclear cells in an acute (nonimmune) inflammatory reaction. Mononuclear cells purified from rat peripheral blood were incubated for 1, 2, or 24 h with 100 or 250 g/ml carrageenin (Cg). The resultant donor supernatant was injected into recipient rats to test its ability to induce hyperalgesia (reduction in threshold for paw pressure) and edema (increase in paw volume). Mononuclear cell supernatants (MnS) induced a significant time- and dose-dependent hyperalgesia and edema in rat paws, which reached a maximal effect at 3 h, lasted for 6 h, and returned to basal levels at 24 h of injection. Prostaglandins and cytokines (interleukin 1, 2, 6, 8, and tumor necrosis factor alpha) accounted for the hyperalgesia induced by MnS, as it was reduced (40 to 90%) by synthesis inhibitors such as indomethacin, dexamethasone, rolipram, and cyclosporin added to the cultures at a microgram dose-range. Edema was dependent on serotonin release in rat paws. These results indicate that mononuclear cells may be important contributors to acute inflammatory reactions, especially under those conditions where pain is an important component.  相似文献   

5.
The potential of human monocytes to mediate the clearance of Bordetella pertussis infection was examined. Bacteria expressing green fluorescent protein were incubated with adherent peripheral blood monocytes, and phagocytosis was quantified by using fluorescence microscopy. Monocytes internalized only a small percentage of the adherent bacteria. Surface-associated Bvg-regulated virulence factors, including adenylate cyclase toxin and filamentous hemagglutinin, did not affect attachment or phagocytosis. However, 1-h pretreatment with purified pertussis toxin inhibited the ability of monocytes to internalize wild-type bacteria. Mutations affecting the terminal trisaccharide of lipopolysaccharide resulted in reduced internalization without affecting adherence of bacteria to monocytes. Opsonization with human serum played only a modest role in promoting phagocytosis. The viability of internalized bacteria was determined by colony counts following treatment with polymyxin B and gentamicin. Less than 1% of internalized bacteria remained viable. These results suggest that pertussis toxin plays a role in the evasion of monocyte phagocytosis and that these cells represent a potential mediator of the clearance of B. pertussis infection.  相似文献   

6.
7.
There is evidence indicating that regular consumption of tomato products is associated with favorable immunomodulatory effects. In addition, tomato extracts have been shown to possess antioxidant, anticarcinogenic and antithrombotic activity in vitro.

Since tomatoes are rich in carotenoids and particularly in lycopene—the pigment responsible for the red color of tomatoes—the present work was designed to examine the in vitro effect of lycopene on cytokine production by peripheral blood mononuclear cells (PBMC) from 15 healthy subjects. First, 2 × 106 PBMC suspended in 1 ml of conditioned medium were incubated over a period of 24 and 48 hours without or with the following concentrations of lycopene: 0.25, 0.5, 1.0, 2.0 and 4.0 μM. The production of the subsequent cytokines was evaluated: IL-1β, IL-1ra, IL-2, IL‐6 and IL-10, as well as TNFα and IFNγ. Lycopene induced a dose-dependent increase in IL1β, and TNFα production and a decrease in IL-2, IL-10 and IFNγ secretion, whereas that of IL-6 and IL-1ra was not affected. It is concluded that understanding the role of lycopene in modulation of the immune system may promote decisions as for dietary supplementation of lycopene for reducing the risk of certain diseases.  相似文献   

8.
新生儿和成人PBMC中IL-4基因表达和NF-AT活性的比较   总被引:2,自引:0,他引:2  
通过比较新生儿脐血单个核细胞 (CBMC)和成人外周血单个核细胞 (PBMC)中IL 4基因表达水平和活化T细胞核因子(NF AT)活性 ,探讨新生儿IL 4基因表达水平低下的机制。用ELISA和RT PCR法测IL 4及其mRNA水平 ;电泳迁移率转换试验 (EMSA)测NF AT活性。结果显示 :抗CD3+PMA刺激后 ,CBMC培养上清液中IL 4水平较PBMC明显低下 (P <0 0 1) ;CBMC产生的IL 4mRNA较PBMC明显减少 ;CBMC核蛋白内几乎测不出NF AT活性 ,而PBMC核蛋白内NF AT活性较强。表明在转录水平上缺乏NF AT调控可能使新生儿IL 4基因转录减少 ,从而导致新生儿IL 4基因表达水平低下。  相似文献   

9.
The aim of the present study was to investigate at 2, 4, and 6 weeks after birth cytokine expression by peripheral blood mononuclear cells and bronchial lymph node cells from piglets infected in utero with porcine reproductive and respiratory syndrome virus (PRRSV). Technically, by flow cytometry we were able to measure gamma interferon (γ-IFN), tumor necrosis factor alpha (TNF-α), interleukin-4 (IL-4), and IL-8 levels. In general, we found increases in the percentages of IL-4-, γ-IFN-, and TNF-α-producing lymphocytes in the infected piglets compared to the percentages in the uninfected control animals, while there was a decrease in the percentage of IL-8-producing monocytes. We believe that these findings reflect a general lymphocyte activation stage that is created due to the infection and that occurs in combination with impairment of the monocyte function, possibly due to the ongoing viral replication in these cells. Single-cell bronchial lymph node preparations exhibited very much the same cytokine profiles as peripheral blood mononuclear cells except for a lack of IL-8 production. When the levels of the individual cytokines in the three groups of PRRSV-infected piglets were compared, the levels of cytokine expression at 4 weeks diverged from those at 2 and 6 weeks, in that there was a significant decrease in the numbers of lymphocytes producing γ-IFN and TNF-α. This tendency was also observed among blood monocytes and lymph node macrophages. Possible reasons for this temporary immunosuppression in the piglets at 4 weeks are discussed.  相似文献   

10.
目的 探讨系统性红斑狼疮(system lupus erythematosus,SLE)患者外周血单个核细胞(peripheral blood monouuclear cells,PBMC)中细胞型Fas相关死亡域样白介素-1β转换酶抑制蛋白(cFLIP)表达的意义.方法 应用半定量RT-PCR方法检测38例SLE患者和21名正常人PBMC中cFLIP-L mRNA和cFLIP-S mRNA的表达水平,并与SLE疾病活动指数(SLEDAI)评分进行相关性分析.结果 ① SLE患者PBMC中cFLIP-L mRNA和cFLIP-S mRNA表达水平均明显高于正常对照组(P<0.01);SLE患者活动组cFLIP-L mRNA表达水平显著高于非活动组(P<0.05),cFLIP-S mRNA表达水平在SLE患者活动组与非活动组之间没有显著性差异(P>0.05). ② SLE患者cFLIP-L mRNA表达水平与SLEDAI评分呈正相关(r=0.423,P<0.01);而cFLIP-S mRNA表达水平与SLEDAI评分无明显相关性(r=0.270,P>0.05).结论 cFLIP-L mRNA和cFLIP-S mRNA可能在SLE发病机制中起重要作用.  相似文献   

11.
Numerous reports have documented that serologic methods are much more sensitive than culture for the diagnosis of pertussis in adolescents and adults. However, a standardized serologic test for pertussis is not routinely available to most clinicians, and the serologic test levels or cutoff points correlated with diseases have not been determined. The goal of the present study was to examine the distribution of immunoglobulin G (IgG) levels against three Bordetella pertussis antigens (pertussis toxin [PT], filamentous hemagglutinin [FHA], and fimbria types 2 and 3 [FIM]) and to determine population-based antibody levels for the purpose of establishing such diagnostic cutoff points. Enzyme-linked immunosorbent assays (ELISAs) were performed with sera from >6,000 U.S. residents aged 6 to 49 years who participated in the Third National Health and Nutrition Examination Survey. Mixture models were developed to identify hypothesized exposure groups and establish diagnostic cutoffs. Quantifiable (>20 ELISA units/ml [EU]) anti-FHA and anti-FIM IgG antibodies were common (65 and 62% of individuals, respectively), but quantifiable anti-PT IgG antibodies were less frequent (16%). Given the distributions of antibody levels, an anti-PT IgG level of ≥94 EU was proposed as the diagnostic cutoff point. Application of this cutoff point to culture-confirmed illness in a prior study investigating cough illness yielded a high diagnostic sensitivity (80%) and specificity (93%). A standardized ELISA for anti-PT IgG with a single serum sample appears to be useful for the identification of recent B. pertussis infection in adolescents and adults with cough illness. The PT cutoff point will be further evaluated in prospective studies of confirmed B. pertussis infection.  相似文献   

12.
13.
Historically, administration of vitamin D has been considered beneficial in the treatment of tuberculosis. The interaction of this vitamin {i.e., 1,25-dihdroxyvitamin D3 [1,25(OH)2D3]} with the antitubercular immune response, however, is not clear. In the present study, in vitro recall responses of peripheral blood mononuclear cells (PBMC) from cattle infected with Mycobacterium bovis were used to study the immune-modulatory effects of 1,25(OH)2D3 on M. bovis-specific responses in vitro. Addition of 1 or 10 nM 1,25(OH)2D3 inhibited M. bovis-specific proliferative responses of PBMC from M. bovis-infected cattle, affecting predominately the CD4+ cell subset. In addition, 1,25(OH)2D3 inhibited M. bovis-specific gamma interferon (IFN-γ) production yet enhanced M. bovis-specific nitric oxide (NO) production. Lymphocyte apoptosis, measured by flow cytometry using annexin-V staining, was diminished by addition of 1,25(OH)2D3 to PBMC cultures. These findings support the current hypothesis that 1,25(OH)2D3 enhances mycobacterial killing by increasing NO production, a potent antimicrobial mechanism of activated macrophages, and suggest that 1,25(OH)2D3 limits host damage by decreasing M. bovis-induced IFN-γ production.  相似文献   

14.
Members of the Mycobacterium tuberculosis (Mtb) Beijing genotype are a major concern due to their high prevalence in tuberculosis patients and their high rate of multi-drug resistance. Although it has been shown that Beijing modifies macrophage behavior, little is known about how this genotype could affect the cellular immune response. In order to address this issue, peripheral blood mononuclear cells (PBMC) from healthy BCG vaccinated individuals were stimulated with protein extracts from three Mycobacterium tuberculosis genotypes: Canetti, H37Rv and Beijing evaluating T cell proliferation and cytokine production. In this system both CD4+ and CD8+ proliferated in a similar manner independently of the Mtb genotype used for stimulation. Regarding cytokines, all strains induced similar levels of IFN-γ, but were unable to induce IL-4 and TGF-β. Contrasting, Canetti strain induced lower production of IL-10, TNF-α and IL-12 compared to H37Rv and Beijing. Interestingly, PBMC stimulated with the Beijing strain produced the highest levels of IL-12 and IL-10 than those stimulated with other strains. This differential cytokine expression could affect the pathogenesis induced by Beijing strain through the modulation of inflammatory process in the host, but the precise mechanisms by which this cytokine environment affects the Beijing strain pathogenesis needs further characterization.  相似文献   

15.
Mycoplasma bovis is a small, cell wall-less bacterium that contributes to a number of chronic inflammatory diseases in both dairy and feedlot cattle, including mastitis and bronchopneumonia. Numerous reports have implicated M. bovis in the activation of the immune system, while at the same time inhibiting immune cell proliferation. However, it is unknown whether the specific immune-cell population M. bovis is capable of attaching to and potentially invading. Here, we demonstrate that incubation of M. bovis Mb1 with bovine peripheral blood mononuclear cells (PBMC) resulted in a significant reduction in their proliferative responses while still remaining viable and capable of gamma interferon secretion. Furthermore, we show that M. bovis Mb1 can be found intracellularly (suggesting a role for either phagocytosis or attachment/invasion) in a number of select bovine PBMC populations (T cells, B cells, monocytes, γδ T cells, dendritic cells, NK cells, cytotoxic T cells, and T-helper cells), as well as red blood cells, albeit it at a significantly lower proportion. M. bovis Mb1 appeared to display three main patterns of intracellular staining: diffuse staining, an association with the intracellular side of the cell membrane, and punctate/vacuole-like staining. The invasion of circulating immune cells and erythrocytes could play an important role in disease pathogenesis by aiding the transport of M. bovis from the lungs to other sites.Mycoplasma bovis is a small, pleomorphic cell wall-less bacterium that is known to be a major contributing factor in the development of chronic pneumonia in feedlot cattle and mastitis in dairy cows. In addition to these two diseases, M. bovis has been linked to the development of otitis, keratoconjunctivitis, and arthritis (12). These diseases have large economic impacts, resulting in losses to both beef and dairy industries in Europe, Canada, and the United States (20). Furthermore, since M. bovis lacks a cell wall, the use of antibiotics to combat infections is limited, and the development of resistance to available antibiotics (tetracyclines and spectinomycin) has been observed (20). Interestingly, infection with M. bovis has been implicated in the potential exacerbation and enhancement of respiratory disease to other pathogens since coinfections with Histophilus somnus, bovine viral diarrhea virus, Mannheimia haemolytica, bovine respiratory syncytial virus, bovine parainfluenza virus type 3 have been observed (3, 4, 16, 25). These findings suggest an important synergism in the development of disease during the coinfection of animals involving M. bovis and other pathogens.A number of factors appear to play an important role in the virulence and development of disease during M. bovis infection, although the specific mechanisms involved in these processes are still incompletely understood. M. bovis lacks a specialized organelle for attachment, as seen in M. pneumoniae and M. genitalium (1, 6), but instead expresses variable surface proteins (Vsps) that play a critical role in its attachment (24). These membrane surface proteins undergo substantial antigenic variation involving high-frequency phenotypic switching, resulting in an increased ability of M. bovis to evade the host''s immune system (13, 14, 21). Furthermore, M. bovis can suppress the immune system via a secreted 26-amino-acid peptide that is 84% homologous to the C-terminal end of the VspL protein (33). This peptide appears to take part in the downregulation of lymphocyte proliferation and thereby ameliorates an appropriate immune response by the host. Another mechanism of immune evasion may involve the ability of M. bovis to inhibit neutrophil oxidative burst by a mechanism that appears to involve protein kinase C signaling (29). M. bovis is also capable of surviving in the environment for an extended period of time via the production of a biofilm, although this biofilm does not appear to enhance its resistance to antibiotics but rather protects it from temperature changes and desiccation (17). Other factors that are believed to play an important role in virulence include the production of hydrogen peroxide and an inflammatory toxin that can result in an increase in vascular permeability and the activation of complement (8, 31, 34).Numerous reports have examined both in vivo and in vitro infections with M. bovis; however, the mechanisms involved during an M. bovis infection have not been fully examined and still remain controversial. Some in vivo research suggests that M. bovis typically adheres to bronchiolar epithelial cell surfaces, localizing between the cells, but does not appear to migrate intracellularly (30). On the other hand, some studies suggest not only that M. bovis attaches to various cell types but also that it is found intracellularly in neutrophils, macrophages, and hepatocytes, whereas bronchiolar epithelial cells displayed positive staining during an M. bovis infection (7, 15, 26). Whether this occurs via an active process in neutrophils and macrophages involving M. bovis itself or a mechanism involving phagocytosis remains to be examined. Studies of other mycoplasmas such as M. gallisepticum and M. suis have demonstrated that they are capable of invading erythrocytes (9, 36), thereby evading the immune system. These studies, along with those of M. bovis, further suggest that mycoplasmas may spread systemically via invasion of peripheral blood mononuclear cells (PBMC) and erythrocytes, while at the same time evading immune responses.Some studies suggest a role for M. bovis-induced activation of various T-cell populations (CD4+, CD8+, and γδ T cells) and the production of specific cytokines (gamma interferon [IFN-γ] and interleukin-4 [IL-4]) (34), tumor necrosis factor alpha, and nitric oxide from bovine macrophages (11). This is not surprising since various reports, including those referred to above, have implicated M. bovis in the modulation of immune responses in vivo and in vitro (28, 29). We demonstrate here that M. bovis Mb1 attaches to and invades bovine PBMC, inhibiting their proliferation, but does not appear to alter functional responses in terms of cytokine production, including IFN-γ in particular. M. bovis invades all of the PBMC types in a relatively short period of time, which could then potentially contribute to an overall suppression of lymphocyte proliferation and possibly spread from the lungs to other organs of the host.  相似文献   

16.
To determine if deoxycytidyl-deoxyguanosine oligonucleotides (CpG ODN) can be used effectively as nonspecific inducers of innate immune defenses for preventative or therapeutic interventions in infectious disease models for nonhuman primates, the present study evaluated the response of rhesus monkey peripheral blood mononuclear cells to three different synthetic CpG ODN classes by defining the cytokine gene expression patterns and by characterizing IFN-α/β responses. Depending on the type and dose of CpG ODN used for stimulation, distinct gene expression patterns were induced. CpG ODN class A (CpG-A ODN) and CpG-C ODN, but not CpG-B ODN, were potent inducers of alpha interferon (IFN-α), and this response was due to IFN-α production by TLR9-positive plasmacytoid dendritic cells. Importantly, there was a dose-dependent increase in IFN-α responses to CpG-A ODN but a dose-dependent decrease in IFN-α responses by CpG-B ODN. The most sustained IFN-α response was induced by CpG-A ODN and was associated with a stronger induction of interferon regulatory factor 7 and the induction of several interferon-stimulated genes. In contrast, and independent of the dose, CpG-B ODN were the weakest inducers of IFN-α but the most potent inducers of proinflammatory cytokines. CpG-C ODN induced cytokine gene expression patterns that were intermediate between those of CpG-A and CpG-B ODN. Thus, the different types of CpG ODN induce different post-TLR9 signaling pathways that result in distinct cytokine gene expression patterns. Based on these findings, A and C class CpG ODN, but not B class CpG ODN, may be particularly suited for use as therapeutic or prophylactic antiviral interventions.

In recent years, many nonhuman primate models of viral infections have been developed to study virus-host interactions and to test the efficacy of possible vaccine candidates (9, 42, 45, 53, 54). Importantly, monkey models of simian immunodeficiency virus (SIV) infection are the best animal models available to study human immunodeficiency virus (HIV) infection and AIDS pathogenesis (48, 49). As the AIDS pandemic continues at an uncontrolled rate, and as new infectious diseases emerge (20, 47), there is an urgent need to design strategies aimed at the prevention of viral transmission and control of early virus replication. Part of this effort is the development of immunomodulatory drugs that have the ability to stimulate innate antiviral immune responses that can block transmission or reduce early virus replication and thereby limit virus dissemination.IFN-α/β are critical cytokines in the initial phase of antiviral immune responses, as they serve two important functions: they exert direct innate antiviral effects via interferon-stimulated genes (ISG), and they promote adaptive cellular antiviral immune responses (6, 11, 12, 14, 18, 29, 32, 39, 40, 43, 51, 52, 57, 58). Thus, the manipulation of the interferon system by immunomodulatory compounds, such as deoxycytidyl-deoxyguanosine oligonucleotides (CpG ODN), has potential utility as a therapeutic intervention aimed at the prevention and control of viral infections (36).There are three main classes of synthetic CpG ODN that differ in the type and magnitude of immune responses induced. CpG ODN of the A class (CpG-A ODN) are very strong inducers of alpha interferon (IFN-α) by plasmacytoid dendritic cells (PDC) and are especially potent NK cell activators (35, 55, 56). CpG-B ODN are weaker inducers of IFN-α, but are potent activators of B cells (25, 35). CpG-C ODN have the combined features of CpG-A and CpG-B ODN: they are strong inducers of PDC IFN-α/β production and strong B-cell activators (24, 44, 67). All classes of CpG ODN promote T helper 1 (Th1) responses to coadministered antigens through the induction of cytokines in activated dendritic cells.Thus, due to the robust induction of IFN-α, CpG-A ODN are potential candidates for prophylactic inducers of innate immune defenses in the prevention of viral infections and other infectious diseases. However, CpG-A ODN are not currently being developed for clinical use, because their poly(G) motifs render them more difficult to produce than the other CpG ODN classes (24, 35). Few studies have yet investigated the immune properties of CpG-C ODN, but based on their known ability to induce strong IFN-α/β production in human cells (24, 44, 67), they could be used for therapeutic interventions in infectious disease settings.Nonhuman primates can respond to the same CpG-A and CpG-B ODN that have strong immune activity in humans, and CpG-B ODN have been used successfully as vaccine adjuvants in several monkey studies (31, 62, 65, 66). However, there are no published reports that CpG ODN can be used effectively for preventative or therapeutic interventions in viral diseases in nonhuman primates or humans.The goal of the present study was to compare the relative suitability of the three CpG ODN classes for in vivo virus studies by defining the gene expression pattern in rhesus monkey peripheral blood mononuclear cells (PBMC) to stimulation with the three CpG ODN classes. Further, we sought to characterize the basis for the very different IFN-α/β responses they induce and to determine the nature of the IFN-α-producing cell types in CpG ODN-stimulated rhesus monkey PBMC. We found that the gene expression pattern induced in rhesus monkey PBMC is dependent on the type and dose of CpG ODN used for stimulation. Thus, CpG-A and CpG-C ODN, but not CpG-B ODN, were potent inducers of IFN-α responses, and this response was mediated predominantly by TLR9-expressing PDC. CpG-A ODN induced the most sustained IFN-α response, and this was associated with a stronger induction of the interferon regulatory factor 7 (IRF-7) and resulted in the strong and prolonged induction of several interferon-stimulated genes. The distinct cytokine expression patterns induced by the different CpG ODN classes suggest that each may have a unique clinical application.  相似文献   

17.
Tumour necrosis factor‐α‐induced protein‐8 like‐2 (TIPE2) is a newly identified immune negative regulator. The abnormal expression of TIPE2 has been found in several human inflammatory diseases. However, the expression level and clinical significance of TIPE2 in childhood asthma remain unclear. In this study, we detected TIPE2 expression in peripheral blood mononuclear cells (PBMC) from 42 children with asthma and 39 healthy controls by RT‐PCR, qRT‐PCR and Western blot. We also detected the levels of serum total immunoglobulin E (IgE), eosinophil (EO), interleukin‐4 (IL‐4) and interferon‐γ (IFN‐γ) and analysed the correlations of TIPE2 expression with IgE, EO, IL‐4 and IFN‐γ. The results showed that TIPE2 mRNA and protein expression were decreased in children with asthma compared with healthy controls. The levels of IgE, EO and IL‐4 in the children with asthma were obviously higher than those in normal controls, while the level of IFN‐γ in patients with asthma was significantly lower than that in healthy subjects. Furthermore, the expression level of TIPE2 mRNA was negatively correlated with IgE, EO and IL‐4. However, no statistically significant correlation was found between TIPE2 mRNA expression and serum IFN‐γ level. In conclusion, our data suggest that reduced TIPE2 expression may contribute to the pathogenesis of childhood asthma.  相似文献   

18.
We studied a well-selected population of patients with active rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) without immunosuppressive therapy. Control and patient peripheral blood mononuclear cells (PBMC) were incubated with IL-1 &#103, IL-10, TGF- &#103 or LPS for 20 h and the in vitro basal and stimulated secretions of IL-6, TNF- &#102, IL-1 &#103 and IL-1ra were measured by ELISA. We found that in the SLE patients the basal secretion of IL-6 was significantly lower and that of IL-1ra significantly higher than in control subjects, while in the RA group the basal IL-1ra secretion was higher than in healthy subjects. SLE and RA PBMC responded to LPS and IL-1 &#103 reaching higher cytokine secretion values than controls. The in vitro response of SLE and RA PBMC to TGF &#103 was normal, while that to IL-10 was defective: IL-10 was able to stimulate the production of IL-6 and IL-1ra in PBMC from normal subjects, but it was unable to enhance IL-6 secretion in RA cells and it was also completely ineffective in inducing IL-1ra secretion in both SLE and RA PBMC. Our work add new data useful for the evaluation of IL-10 and IL-1ra as therapeutic agents in rheumatic diseases.  相似文献   

19.
目的:分析2型糖尿病(T2DM)合并颈动脉粥样硬化(CAS)患者外周血单个核细胞(PBMCs)中衔接蛋白凋亡相关斑点样蛋白(ASC)mRNA的表达及作用。方法:根据华盛顿大学CAS斑块超声分级标准将107例T2DM患者分为单纯T2DM组(n=26)、T2DM轻度斑块组(n=32)、T2DM中度斑块组(n=38)和T2DM重度斑块组(n=11)。另选非T2DM的CAS患者作为单纯CAS组(n=35),以及体检健康者作为正常对照组(n=35)。采用实时荧光定量聚合酶链反应(RT-FQ-PCR)技术检测各组PBMCs中ASC mRNA表达水平。统计分析各组差异及ASC mRNA水平与CAS斑块严重程度的关系。结果:各病例组ASC mRNA表达水平显著高于正常对照组(P0.05),T2DM合并CAS组ASC mRNA表达水平显著高于单纯CAS组(P0.01);ASC mRNA表达水平轻度斑块组中度斑块组重度斑块组,即ASC mRNA表达水平与T2DM患者CAS斑块程度呈明显负相关(r=-0.43,P0.05)。结论:ASC mRNA表达增加可能是T2DM合并AS的发病因素和CAS斑块活跃性的指征。  相似文献   

20.
Human immunodeficiency virus type 1 (HIV-1) infection results in impaired immune function that can be measured by changes in immunophenotypically defined lymphocyte subsets and other in vitro functional assays. These in vitro assays may also serve as early indicators of efficacy when new therapeutic strategies for HIV-1 infection are being evaluated. However, the use of in vitro assays of immune function in multicenter clinical trials has been hindered by their need to be performed on fresh specimens. We assessed the feasibility of using cryopreserved peripheral blood mononuclear cells (PBMC) for lymphocyte immunophenotyping and for lymphocyte proliferation at nine laboratories. In HIV-1-infected patients with moderate CD4+ lymphocyte loss, the procedures of density gradient isolation, cryopreservation, and thawing of PBMC resulted in significant loss of CD19+ B cells but no measurable loss of total T cells or CD4+ or CD8+ T cells. No significant changes were seen in CD28 CD95+ lymphocytes after cell isolation and cryopreservation. However, small decreases in HLA-DR+ CD38+ lymphocytes and of CD45RA+ CD62L+ were observed within both the CD4+ and CD8+ subsets. Fewer than 10% of those specimens that showed positive PBMC proliferative responses to mitogens or microbial antigens lost their responsiveness after cryopreservation. These results support the feasibility of cryopreserving PBMC for immunophenotyping and functional testing in multicenter AIDS clinical trials. However, small changes in selected lymphocyte subsets that may occur after PBMC isolation and cryopreservation will need to be assessed and considered in the design of each clinical trial.  相似文献   

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