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1.
The cellular response in the course of experimental infection with Salmonella typhimurium was studied in mice. T cells were detected by the presence of theta-antigen, B cells by the binding of fluorescent immunoglobulins, and cells with receptors by labeled Salmonella binding. Lymphocytes were from spleen and lymph nodes. Results have been divided into three groups: group A, including mice with slight symptomatology; group B, including those with serious infection symptomatology; and group C, including mice that died in the course of the experiment. In spleen and lymph nodes of group A mice, an increase in the percentage of T and B lymphocytes was observed. This increase reached a peak 10 days after experimental infection. In lymph nodes, the B-cell percentage was equal to the percentage of T cells, whereas in spleen lymphocytes the B-cell percentage was higher. In spleens of group B mice we observed the same response as in mice of group A, whereas in lymph nodes there was a low response of T and B lymphocytes. In group C mice, there was no significant response of T and B lymphocytes in either spleen or lymph nodes. In B lymphocytes prepared from spleens of surviving mice, a small number of Salmonella receptors was detected: 200 bacterial cells per 10(9) lymphocytes.  相似文献   

2.
The ability of mice to clear Salmonella typhimurium from their spleens in the late phase of infection was studied after inoculation with a temperature-sensitive mutant. Clearance of bacteria was delayed in C57BL/6 mice compared with BALB/c, C3H/HeJ, DBA/2, A/J, and CBA mice. The responses of F1 hybrids, backcrosses, and recombinant inbred strains derived from C57BL/6 and BALB/c (both Itys) and of H-2 congenic mice were analyzed. The results showed that the low rate of bacterial clearance was recessive, that the rate of clearance was under polygenic control, and that an H-2-linked gene(s) plays a major role. Among H-2 congenic mice with a C57BL/10 background, three phenotypes of bacterial clearance could be distinguished: high (H-2j, H-2q, and H-2u), intermediate (H-2d, H-2f, H-2k, H-2p, H-2r, H-2s, and H-2v), and low (H-2b) rates. The effect of the H-2 complex was apparent with different genetic backgrounds (Itys and Ityr). In recombinant inbred strains derived from C57BL/6 (Itys) and A/J (Ityr) mice, the effect of the H-2b haplotype on bacterial clearance appeared to be fully expressed only in strains carrying the Itys allele.  相似文献   

3.
Factors responsible for the predictable generation of Th1 or Th2 immune responses to microorganisms in vivo are not well characterized, although the ability of antigen presenting cells (APC) to provide co-stimulation, the kinetics of MHC-peptide ligand generation as well as the cytokine environment are all considered important factors for the differential Th1/Th2 priming of T cells. Our earlier findings of an IFN-gamma-dominant, Th1-type response to live Salmonella typhimurium (Stm) and a Th2-type response to killed Stm suggested that persistence of viable bacteria might be an important factor in the generation of IFN-gamma-dominant responses. Using genetically susceptible and resistant strains of mice to limit bacterial replication and persistence in vivo, we show that mice of the lty(r) genotype, capable of a 10-fold better clearance of Stm, mount an IFN-gamma-dominant immune response following immunization with live Stm similar to that in the lty(s) strain. Further, metabolically defective mutants of Stm, aroA and purA, when used in the live form, also elicit IFN-gamma-dominant immune responses similar to the wild-type Stm strain despite their inability to proliferate in vivo. While a laboratory strain of Escherichia coli, which is antigenically cross-reactive but non-invasive, elicits hardly any IFN-gamma in immune responses, an invasive strain of E. coil induces an IFN-gamma-dominant response. These data together indicate that, while entry of bacteria into macrophages is likely to be critical for the generation of IFN-gamma-dominant immune responses, their persistence is not.  相似文献   

4.
In understanding the regulation of the specific immune response to Salmonella typhimurium, the role of a surface major component (porins) was studied. In this study we demonstrate that purified porins are able to induce a different response to that induced by the porins present on the S. typhimurium cell surface. Porin-treated or orally infected mice show anti-porin antibodies with bactericidal activity. The complete adoptive transfer of resistance to S. typhimurium is achieved only using splenic T cells from survivor mice after experimental infection. After stimulation with specific antigen in vitro CD4+ cells from porin-immunized mice released large amounts of interleukin-4 (IL-4), at a time when CD4+ cells from S. typhimurium-infected mice predominantly secreted interferon-gamma (IFN-gamma). Limiting dilution analysis showed that infection resulted in a higher precursor frequency of IFN-gamma-producing CD4+ T cells and a lower precursor frequency of IL-4-producing CD4+ T cells, while immunization with porins resulted in a higher precursor frequency of IL-4-producing cells and a low frequency of IFN-gamma-producing cells. Analysis of polymerase chain reaction-amplified cDNA from the spleens of infected mice revealed that IFN-gamma, IL-2 and IL-12 p40 mRNA were found 5 days after in vitro challenge and increased after 15 days; IL-10 expression was barely present after both 5 and 15 days, while IL-4 mRNA expression was not detected. In immunized mice, the IL-4 mRNA expression increased after 15 days, IFN-gamma mRNA expression disappeared entirely after 15 days, while IL-2, IL-10 and IL-12 mRNA remained relatively unchanged.  相似文献   

5.
Scanning electron microscopy demonstrates that crystalline silica destroys liver Kupffer cells but has no other obvious deleterious effects on the liver. Silica-treated livers still retain the ability to trap large numbers of bacteria perfused through the portal vein even though the rate of clearance is well below normal. In vivo, silica treatment decreases the rate of bacterial clearance from the blood, alters the in vivo organ distribution of cleared bacteria, and decreases the mean lethal dose of Salmonella typhimurium over 100-fold. Cumulatively, the data indicate that silica treatment enhances susceptibility to gram-negative infection, probably by destruction of macrophages.  相似文献   

6.
Clearance of disseminated Salmonella infection requires bacterial-specific Th1 cells and IFN-γ production, and Th1-promoting vaccines are likely to help control these infections. Consequently, vaccine design has focused on developing Th1-polarizing adjuvants or Ag that naturally induce Th1 responses. In this study, we show that, in mice, immunization with soluble, recombinant FliC protein flagellin (sFliC) induces Th2 responses as evidenced by Ag-specific GATA-3, IL-4 mRNA, and protein induction in CD62L(lo) CD4(+) T cells without associated IFN-γ production. Despite these Th2 features, sFliC immunization can enhance the development of protective Th1 immunity during subsequent Salmonella infection in an Ab-independent, T-cell-dependent manner. Salmonella infection in sFliC-immunized mice resulted in augmented Th1 responses, with greater bacterial clearance and increased numbers of IFN-γ-producing CD4(+) T cells, despite the early induction of Th2 features to sFliC. The augmented Th1 immunity after sFliC immunization was regulated by T-bet although T-bet is dispensable for primary responses to sFliC. These findings show that there can be flexibility in T-cell responses to some subunit vaccines. These vaccines may induce Th2-type immunity during primary immunization yet promote Th1-dependent responses during later infection. This suggests that designing Th1-inducing subunit vaccines may not always be necessary since this can occur naturally during subsequent infection.  相似文献   

7.
8.
Protein A (PA) of Staphylococcus aureus is known to elicit several cytokines such as IFN gamma, TNF alpha and IL1. However, it has not been delineated yet as to which differentiation pathway lymphocytes follow after stimulation by PA. In this report, we attempted to collect such evidences. Cytokines, such as IFN gamma, IL2, IL4, IL6, IL10, TNF alpha, IL1alpha and IL1beta were measured in serum by ELISA. Our results show that 1 microg dose of PA stimulates the production of IFN gamma (115 +/- 5 pg/ml), TNF alpha (250 +/- 8 pg/ml) and IL1alpha (100 +/- 5 pg/ml) as compared to control levels of, 22 +/- 2, 20 +/- 2 and 35 +/- 3 pg/ml respectively whereas IL2 and IL1beta secretion were less (beyond the lower detection limit of the kit and 25 +/- 1 pg/ml, respectively) as compared to control (28 +/- 2 and 52 +/- 4 pg/ml, respectively). Larger dose of PA (10 microg) increases the expression of IL2 (75 +/- 3 pg/ml), TNF alpha (1380 +/- 120 pg/ml), IL1alpha (495 +/- 10 pg/ml) and IL1beta (110 +/- 7 pg/ml) as compared to controls described above. We also observed that 1 microg dose of PA decreases IL4, IL6 and IL10 secretion to 9 +/- 1, 10 +/- 1 and 10 +/- 2 pg/ml, respectively, whereas 10 microg dose also decreased them to 11 +/- 1, 12 +/- 2 and 30 +/- 4 pg/ml, respectively as compared to the background controls, i.e. 50 +/- 5, 50 +/- 2 and 215 +/- 9 pg/ml respectively. The ratio of IFN gamma to IL4 increased and the peak value at 4 h, came to 13 +/- 1 and 9.6 +/- 0.5 with 1 microg and 10 microg PA, respectively, which is an established parameter indicating a Th1 type response. Flow cytometry analysis of CD4+/CD8+ cells, and c-myc protein expression by splenocytes indicate that 1 microg dose of PA causes 2-fold increase of CD4+ cells with no change in CD8+ cells, and 10-fold increase in c-myc protein, whereas 10 microg dose increases CD4+ cells 4-fold, CD8+ cells 3-fold and c-myc protein 100-fold. The cell cycle data shows an induction of apoptosis in thymocytes and splenocytes with the large dose (10 microg), whereas the 1 microg dose does not show any apoptosis. This report indicates that a Th1 response is induced in mice, after PA inoculation at a dose of 1 microg animal. Thus, cytokine mediated therapeutic strategies should consider the fact that an induction of large concentration of some cytokines might become detrimental to the host.  相似文献   

9.
BACKGROUND: Olive pollen is one of the main causes of allergy in Mediterranean countries, where it is widely distributed. One inconvenience in studying new immunotherapies for olive pollen allergy is the lack of suitable animal models. The aim of this study was to develop a murine model of IgE sensitization to Ole e 1, the major allergen of olive pollen, which mimics the immunological features of olive pollinosis in humans and to investigate the in vivo antigenicity of the recombinant form of the allergen. METHODS: BALB/c mice were sensitized by intraperitoneal administration of natural Ole e 1 (nOle e 1) and recombinant Ole e 1 (rOle e 1) in Al(OH)(3), respectively. Serum levels of specific IgE, IgG1 and IgG2a, cytokine production and the proliferative response of splenocytes after in vitro stimulation with nOle e 1 were analyzed by ELISA and flow cytometry. The binding capacity of rOle e 1-specific IgG1 was examined by ELISA and immunoblotting. RESULTS: Sensitization with nOle e 1 or rOle e 1 induced high levels of specific IgE and IgG1 versus low IgG2a antibody levels. Splenocytes from sensitized mice exhibited a proliferative response to nOle e 1. In vitro stimulated splenic cells from nOle e 1-primed mice produced IL-4 and low or nondetectable levels of IFN-gamma. Specific IgE and IgG1 antibodies of immunized mice bound to the same Ole e 1 isoforms and showed a similar degree of cross-reactivity as observed for human IgE. Mouse specific nOle e 1 IgG1 was strongly inhibited by IgE from allergic patients. The IgG1 antibodies elicited by rOle e 1 reacted with both the recombinant and natural forms of the allergen. CONCLUSIONS: A murine model of Ole e 1 sensitization has been established. rOle e 1 shows similar allergenicity and antigenicity to its natural form. This model should provide a useful tool for evaluating antigenic molecules and exploring new therapeutic approaches in order to treat IgE-mediated olive pollinosis.  相似文献   

10.
G Doria  G Agarossi    G Biozzi 《Immunology》1978,34(6):999-1005
The aim of this study was the identification of the cell type in which genes selected for high or low response to SRBC express their functions. Spleen cells from high (H) and low (L) responder mice were immunized with SRBC in the Mishell and Dutton system. An antibody response of different magnitude was found in cultures of H and L spleen cells, the difference being at least as great as that observed in vivo. This finding under experimental conditions allowing the exclusion of any influence of the animal milieu during the immune response, suggest macrophages, B, and T lymphocytes as possible target cells of gene action. In vitro cell separation and recombination experiments in which spleen cells were immunized with SRBC, TNP-LPS, or TNP-HRBC indicate that the genetic differences between H and L responders brought about by selective breeding are expressed in lymphocytes to greater extent than in macrophages. The role of histoincompatibility in the recombination experiments in unlikely but cannot be excluded. Among lymphocytes, B cells but not helper T cells were found more responsive in cultures of spleen cells from H than from L mice.  相似文献   

11.
The exact role of T-helper (Th) cells that precede the clinical manifestation of type 1 diabetes remains unclear. The aim of this investigation was to study the Th1- and Th2-like profile in children and adults with high risk of developing the disease. Peripheral blood mononuclear cells were collected from high-risk children and adults and from healthy individuals matched for age and gender. Using the sensitive enzyme-linked immunospot (ELISPOT) technique to divide Th1- from Th2-like lymphocytes, secretion of interferon-gamma (IFN-gamma) and interleukin-4 was analysed from lymphocytes spontaneously and after in vitro stimulation with different antigens, based on present paradigms regarding the pathogenesis of type 1 diabetes. Compared to the response observed in healthy individuals, we found that individuals with a high risk of developing type 1 diabetes, especially children, responded with less IFN-gamma secretion to the three autoantigens glutamic acid decarboxylase 65 (GAD65), insulin and tyrosinphosphatase (IA-2). Thus, a diminished Th1-like response by in vitro autoantigen stimulation was observed in especially children with a high risk of developing type 1 diabetes. Reduced Th1/Th2 response was related to signs of beta cell exhaustion.  相似文献   

12.
质粒DNA促进HBsAg-抗HBs复合型疫苗诱生的免疫应答的研究   总被引:1,自引:0,他引:1  
目的 研究HBsAg 抗HBs 质粒DNA复合型疫苗的免疫原性及其诱生细胞免疫应答的类型。方法 分别以HBsAg、HBsAg 抗 HBs(IC)、pI/AmpHBs、IC pI/AmpHBs及IC pI/Amp免疫小鼠 ,检测抗 HBs的效价 ,分析抗 HBsIgG亚类 (ELISA) ;取免疫小鼠脾细胞 ,体外抗原刺激 ,用竞争性RT PCR方法检测IFN γ及IL 4mRNA转录水平。结果 IC pI/AmpHBs诱生的抗 HBs效价明显高于IC或pI/AmpHBs单独免疫组 ,其IgG2a/IgG1比值高于IC免疫组 ,而低于pI/AmpHBs免疫组。IC pI/AmpHBs免疫小鼠脾细胞在HBsAg刺激下 ,IFN γmRNA转录水平明显高于其他免疫组 ,其IFN γmRNA的T/C(目的片段Target/竞争片段Competitor)比值为IC免疫小鼠脾细胞的 10倍 ;IC pI/AmpHBs免疫小鼠脾细胞IL 4mRNA转录水平亦高于其他免疫组 ,其IL 4mRNA的T/C比值为IC免疫小鼠脾细胞的 2倍。结论 HBsAg 抗HBs 质粒DNA复合型疫苗在增强体液免疫应答的同时可诱导脾细胞IFN γ的表达水平增高。  相似文献   

13.
Mice selected by Biozzi for high and low responses to sheep erythrocytes were investigated for resistance to subcutaneous Salmonella typhimurium infection. The resistance was measured by LD50 values, viable bacterial counts in liver and spleen at 10 days, and the kinetics of infection over 4 weeks. High responder mice were susceptible to S. typhimurium injected subcutaneously (LD50 less than 10) and low line resistant (LD50 3 x 10(6)). Control of natural resistance to S. typhimurium in inbred mice is primarily by a single gene. Ity, on chromosome 1. Results with hybrid generations of Biozzi mice with either BALB/c (sensitive) or CBA (resistant) inbred mice indicated additional genetic control of resistance in Biozzi mice. Analysis of resistance data of backcrosses of (high x low)F1 with either parental strain showed this genetic control to be at least one other gene in the Biozzi mice, not linked to Ity. The antibody responses in the hybrid generations and inbred and Biozzi parental strains were tested by haemagglutination assays and ELISA. After specific stimulation of the mice there was an inverse relationship between resistance to S. typhimurium and antibody levels.  相似文献   

14.
Disseminated infection caused by organisms of Mycobacterium avium complex is common in acquired immune deficiency syndrome (AIDS) patients. M. avium is an intracellular bacterium that multiplies within macrophages. We examined the effect of M. avium infection on the T-helper cell response in C57/BL/6 black mice. At weekly intervals, CD4+ T-cells were isolated from spleens and lines were created. T-cell lines were exposed to sonicated M. avium in the presence of feeder cells and macrophages and the supernatant were collected to measure the concentrations of interferon-gamma (IFN-gamma and interleukin-10 (IL-10). Production of IFN-gamma in CD4+ T-cells obtained from uninfected mice did not vary significantly during the 5 weeks. Levels of IFN-gamma produced by T-cell lines of infected mice were similar to the control mice during the first 2 weeks but significantly reduced (approximately 30 ng/ml) thereafter. In contrast, production of IL-10 by T-cell lines of infected mice was in a range of 190 to 342 pg/ml in weeks 1, 2 and 3, but increased to an average of 1300 pg/ml at weeks 4 and 5. Pre-immunized mice, when infected with M. avium strain 101, showed a different profile of T-cell cytokines, with high IFN-gamma and low IL-10 production. Proteins purified from a number of disease-associated (D-A) and non-D-A strains of M. avium were tested for the ability to induce IL-10. 65,000 MW and 60,000 MW proteins of M. avium induced significantly more IL-10 than 45,000 MW, 33,000 MW and 27,000 MW proteins. These results showed that M. avium predominantly stimulates either Th1 or Th2 T-helper cells according to the phase of the infection.  相似文献   

15.
Glycation increases the vascular clearance rate of IgG in mice.   总被引:1,自引:0,他引:1       下载免费PDF全文
As elevated levels of glycated IgG have been detected in the plasma of diabetics we have investigated whether glycation of IgG affects its vascular clearance rate, using a mouse model system. Polyclonal mouse IgG was aseptically incubated for 14-19 days with 0.5 M glucose in 0.1 M phosphate buffer (pH 7.4) at 37 degrees C. As control, IgG was incubated under identical conditions but with no added glucose. After incubation, both forms were labelled with 125I and injected intravenously into BALB/c mice. The rate of vascular clearance of the glycated IgG was found to be significantly higher than the control IgG in the periods 5-24 h (P < 0.001, n = 6) and 24-48 h (P < 0.01, n = 6) after injection. After 2-3 days the mice were killed and the major organs were harvested. With glycated IgG there was a significant increase in the 125I accumulated in the kidney (P < 0.02). In later experiments, dual labelling with 131I and 125I allowed mixtures of glycated and unglycated IgG to be injected into the same mouse so that the vascular clearance of both forms of IgG could be followed simultaneously. These experiments confirmed that glycation of the IgG significantly increases its vascular clearance rate.  相似文献   

16.
The roles that T helper type 1 (Th1) and T helper type 2 (Th2) Helicobacter pylori-specific immune responses play in protection from H. pylori challenge are poorly understood. It is expected that Th2 immune responses are required for protection against extracellular bacteria, such as H. pylori. However, recent studies have suggested that Th1 immunity is required for protection. The mechanisms by which this might occur are unknown. Our goal in this study was to more clearly define the effects of a Th1- versus a Th2-promoting H. pylori vaccine on immunity and protection. Therefore, we tested a Th1 vaccine consisting of an H. pylori sonicate and CpG oligonucleotides (CpG) and a Th2 vaccine consisting of a lipopolysaccharide (LPS)-depleted H. pylori sonicate combined with cholera toxin (CT). We demonstrate that although the Th2-promoting vaccine induced stronger systemic and local immune responses, only the Th1-promoting vaccine was protective.  相似文献   

17.
目的:研究旋毛虫(T.spiralis)对肠炎小鼠[三硝基苯磺酸(TNBS)或唑酮(OXZ)诱导]脾脏淋巴细胞中Th1/Th2水平的影响。方法:雌性BALB/c小鼠,随机分为50%乙醇对照组、TNBS(OXZ)诱导肠炎模型组、预先感染T.spiralis后诱导TNBS(OXZ)模型组,每组小鼠取材时保证6只以上。对各组小鼠脾脏淋巴细胞进行分离,采用流式细胞术观察TNBS(OXZ)诱导肠炎模型组和预先感染T.spiralis后诱导TNBS(OXZ)模型组。造模后3 d和7 d脾脏淋巴细胞中Th1/Th2水平的变化。结果:与模型组相比,预先感染T.spiralis后诱导TNBS肠炎第3天脾脏Th1/Th2比值未见明显下降(P>0.05),于第7天明显降低(P<0.05)。诱导OXZ肠炎模型后第3天及第7天小鼠脾脏Th1/Th2比值均明显低于T.spiralis干预组(P<0.05)。结论:针对TNBS 肠炎模型,T.spiralis可能是通过诱导Th2及Tr1型免疫反应抑制模型小鼠过度的Th1型免疫而起到良好的干预作用。在T.spiralis对OXZ模型小鼠的干预性研究中,并无T.spiralis感染诱发的Th2型炎症反应加重同样以Th2升高为主的OXZ模型小鼠的病情。  相似文献   

18.
Resistance and susceptibility to mycobacterial infection in the Biozzi high and low lines of mice which were genetically selected for their responses to heterologous erythrocytes have been found to be related to the innate ability of nonimmune macrophages to kill or inhibit the growth of the organisms during the first two weeks after infection and to their ability to mount specific and nonspecific immune responses. High antibody-producer mice were more capable of expressing cell-mediated immune parameters than low antibody-producer mice. A direct relationship was observed between the ability of bacteria (BCG vaccine) to multiply inside the reticuloendothelial system and the development of cell-mediated immunity, as measured by the delayed local reaction at the injection site, the lymphoproliferative response in the draining nodes, the tuberculin delayed-type hypersensitivity, the acquired resistance, and the adjuvant effect after BCG inoculation. In high line mice, apart from the inability of their macrophages to inhibit the early growth of bacteria, their lymphocytes in spleen and thymus were more capable of being stimulated in vitro by varying concentrations of living BCG. The data presented in this report are compatible with the hypothesis that a group of genes segregated in each line during the selective breeding controls the innate microbicidal activity.  相似文献   

19.
CpG ODN对rHBsAg免疫小鼠Th1/Th2型免疫应答的影响   总被引:5,自引:2,他引:5  
目的:初步探讨CpC寡脱氧核苷酸(CpG ODN)与重组乙型肝炎表面抗原(rHBsAg)联合免疫小鼠的Th1/Th2型免疫应答效应。方法:BALB/c小鼠经后腿胫骨前肌免疫2次,ELISA法检测血清乙型肝炎表面抗体(抗-HBs)IgG亚类IgG2a/IgG1的比值;生物活性法检测脾细胞诱生上清中的IFN-γ和IL-2含量;ABC-ELISA法检测小鼠血清中IL-4、IL-10及IL-12含量。结果:加CpG ODN组与单独注射rHBsAg组相比:抗-HBs IgG亚类IgG2a/IgG1比值明显高;Th1型细胞因子IFN-γ和IL-2的表达增强,抑制Th2型细胞因子IL-4和IL-10的产生。结论:CpCODN能够明显增强rHBsAg免疫小鼠Th1型抗体亚类IgG2a的产生,并且诱导Th1型细胞因子的表达,抑制Th2型细胞因子的表达。  相似文献   

20.

Aims

The effects of T helper (Th) cells on alcoholic cardiomyopathy have not been extensively investigated. Strain of mice with Th1 or Th2 immunological background were utilized in this study in order to explore the role of Th1/Th2 in chronic alcohol-induced cardiac fibrosis.

Methods and results

C57BL/6 WT or Balb/c mice were treated with alcohol for 90 days. Then cardiac structure and function were analyzed via echocardiography. Spleen CD4 + CD25 + Foxp3+ Tregs were determined by flow cytometry. The hearts were stained using haematoxylin and eosin (HE) and Masson's trichome. Myocardial ultrastructure was observed by electron microscopy. Expression of T-bet, GATA-3, IL-4 and IFN-gamma were determined by real-time RT-PCR. The heart was dilated significantly in the C57BL/6 WT + alcohol group and Balb/c + alcohol group compared with the controls. CD4 + CD25 + Foxp3+ Tregs were not statistically different. Masson's trichome staining revealed that fibrosis was more pronounced in the alcohol treated groups than the controls. Fibrosis was more evident in the Balb/c + alcohol group compared to the C57BL/6 WT + alcohol group. Alcohol consumption caused a decrease in the Th1 poalrization and an increase in the Th2 response.

Conclusions

Chronic alcohol consumption induced a Th2 response within the Th1/Th2 balance. Th2 response is one of the underlying mechanism involved in alcohol-induced cardiac fibrosis.  相似文献   

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