Results in immunology最新文献

Avian pathogenic Escherichia coli (APEC) causes colibacillosis, which is responsible for morbidity and mortality in chickens. Gene expression patterns have previously been demonstrated to differ between chicken populations that are resistant vs. susceptible to bacterial infection, but little is currently known about gene expression response to APEC. Increased understanding of gene expression patterns associated with resistance will facilitate genetic selection to increase resistance to APEC. Male broiler chicks were vaccinated at 2 weeks of age and challenged with APEC at 4 weeks of age. Peripheral blood leukocytes were collected at 1 and 5 day post-infection. Lesions on the liver, pericardium, and air sacs were used to assign a mild or severe pathology status to non-vaccinated, challenged chicks. Ten treatment groups were therefore generated with a priori factors of vaccination, challenge, day post-infection, and the a posteriori factor of pathology status. Global transcriptomic response was evaluated using the Agilent 44K chicken microarray. APEC infection resulted in more up-regulation than down-regulation of differentially expressed genes. Immune response and metabolic processes were enriched with differentially expressed genes. Although vaccination significantly reduced lesions in challenged bird, there was no detectable effect of vaccination on gene expression. This study investigated the transcriptomic differences in host responses associated with mild vs. severe pathology, in addition to the effects of vaccination and challenge, thus revealing genes and networks associated with response to APEC and providing a foundation for future studies on, and genetic selection for, genetic resistance to APEC.

The molecular mechanisms by which disseminated neoplasia (DN) is developed in soft shell clams Mya arenaria remain largely unknown. This study aims at quantifying Rho-like GTPase, RAS-Rho, RAS-related C3 botulinum (RAS C3), c-jun as well as c-myc transcript levels in clams sampled at North River (Charlottetown, Prince Edward Island, Canada). The transcripts were quantified using multiplex gene analysis (Quantigene^® 2 Plex, Affymetrix) in 3 groups of clams: (1) Group C (healthy clams considered as control) with a low percentage of tetraploid hemocytes (<10%); (2) Group D (disease in development): individuals presenting a percentage of tetraploid cells ranging between 10% and 50%; (3) Group E (established disease): clams with a high percentage of tetraploid hemocytes (>50%). Data showed a down-regulation of Rho-like GTPase, Rho-like subfamily, RAS C3, c-jun and an up-regulation of c-myc gene expression. It is believed that a deregulation of the expression of these genes could partly unravel the molecular mechanisms involved in the development of DN in soft shell clams Mya arenaria. Further investigations should be pursued to determine the role of these gene products in clams' hemocytes.

CD2 family receptor (CD2f) is evolutionarily conserved and is widely expressed by various types of leukocytes. To elucidate the phylogenetic diversity of the CD2f, we characterized CD2f in teleosts using ginbuna crucian carp and zebrafish. The identified CD2f isoforms of the ginbuna carp (caauCD2f) exhibited high sequence similarity to the mammalian CD2 subsets CD48, CD244, and CD319, but it was difficult to classify them into their respective mammalian CD2f based on sequence similarity, the presence of an immunoreceptor tyrosine-based switch motif (ITSM), and phylogenetic tree analysis. Although the four caauCD2f isoforms share an extracellular domain with quite high identity (83–94% identity at the nucleic acid level), they differ in the number of ITSM motifs in their cytoplasmic tail. RT-PCR and in situ hybridization analyses showed that the caauCD2f isoforms are expressed by different cell populations, suggesting that they, like mammalian CD2f, have diverse roles. Interestingly, immunoglobulin (Ig) domain-like sequences with high identity to caauCD2fs are clustered close together within 0.6 Mbp on zebrafish chromosomes 1 and 2 (at least 8 and 35 sequences, respectively), and many pairs of the Ig domains share more than 90% identity at the amino acid level. Therefore, the teleost CD2fs with considerably high identity have been probably generated from a common ancestral Ig-domain gene by a very recent gene duplication event. These findings suggest that the identified CD2f acquired functional diversification through successive duplications together with the acquisition of ITSM.

The aim of this study was to determine the effect of HNSCC tumour treatment on systemic Th1 and Th2 cytokine levels and investigate correlations with clinicopathological parameters. IL2, IL4, IL5, IL6, IL8, IL10, IL13, GMCSF, IFNγ and TNFα were measured in the serum of 101 newly-presenting HNSCC patients (9 oral cavity, 27 oropharynx, 57 laryngopharynx, 1 sinonasal, 1 parotid and 6 unknown), prior to and following treatment, using a Quantibody^® array based multiplex sandwich ELISA (Raybiotech). Data were analysed with respect to T stage, nodal status, age and sex of the patient as well as time between collection of pre- and post-treatment serum. A significant decrease in the levels of the Th2 cytokines IL4, IL5, IL6 and IL10 and the Th1 cytokines IL2 and IL8 was observed between the pre- and post-treatment serum samples. IL13 and TNFα were significantly higher in early stage (T1/T2) tumours compared with late stage (T3/T4) and this trend was maintained for nodal involvement. IL4 was higher in node positive patients compared with node negative, whereas the converse was true for IL2; IL4 was also higher in younger patients compared with the older age group. These results suggest that removal of HNSCC tumours from patients results in reduced circulating Th2 cytokines without a concurrent increase in Th1 cytokines, indicative of a partial rebalance of the Th1/Th2 system following treatment. Furthermore the cytokine profile may be influenced by the size and nodal involvement of the tumour.

Background

We have reported that anti-phosphorylcholine (anti-PC) IgM is a protection marker for human cardiovascular disease (CVD) and atherosclerosis. We here investigate the anti-PC autoantibodies in a well-defined cohort with regard to idiotype, atherosclerosis progression and mechanisms for its protective action.

Methods

Serum levels and binding specificities of different anti-PC isotypes were determined in 226 hypertensive individuals enrolled in European Lacidipine Study on Atherosclerosis using ELISA. The mean of the maximum Intima-Media Thicknesses (IMT) in the far walls of common carotids and bifurcations was assessed at the time of inclusion, and four years afterwards. Apoptosis in immune cells was induced with lysophosphatidylcholine (LPC) and quantified using the MTT-assay.

Results

Anti-PC IgM, IgA and IgG1 (but not IgG2) was negatively associated with IMT-progression. Combining anti-PC IgM with data on antibodies against oxidized- and malondialdehyde-modified LDL further strengthened this association. At very high levels, anti-PC IgM exhibited a striking negative association with atherosclerosis progression (OR 0.05; CI 0.006–0.40). Analysis of serum samples taken four years apart in study participants affirmed the stability of anti-PC IgM titers over time. Examination of fine specificities revealed that the protective isotypes (IgM, IgA and IgG1) are of the Group I idiotype whereas the non-protective IgG2 subclass was Group II. Anti-PC IgM inhibited LPC-induced cell death of immune cells.

Conclusion

Group I anti-PC antibodies, particularly of the IgM class, are independent protection markers for atherosclerosis progression. One potential mechanism of action is inhibition of LPC-induced cell cytotoxicity.

TLR2 agonists are well known for inducing NF-kB activation and inflammation, while estrogen receptor-alpha (ER-α) is a regulator of estrogen-mediated anti-inflammatory responses. In the present work, we determined the role of ER-α and phosphorylated ER-α in TLR2 agonist-induced MCP1 production in mesangial cells. We found that TLR2 agonists induced nuclear localization of phospho-ER-α (serine 118), and estrogen and TLR2 agonists both induced phosphorylation of ER-α at the serine 118 and 104/106 positions. Incubation of MRL/lpr mesangial cells with estrogen was found to attenuate TLR2 agonist-mediated MCP1 production. To determine the mode of action of ER-α/pER-α (serine-118), we used the ER-α inhibitor MPP and transfected mesangial cells with ER-α siRNA. ER-α inhibition was found to decrease MCP1 production in mesangial cells. Thus, ER-α/pER-α is an intermediate regulator for both TLR2-mediated MCP1 production during inflammation and estrogen-mediated anti-inflammatory signals in mesangial cells.

T cells are involved in the pathogenesis of rheumatoid arthritis (RA). CD6 is a co-stimulatory molecule, predominantly expressed on lymphocytes, that has been linked to autoreactive responses. The purpose of this study was to evaluate the safety, immunogenicity and preliminary efficacy of itolizumab, a humanized anti-CD6 monoclonal antibody, in patients with active rheumatoid arthritis. Fifteen patients were enrolled in a phase I, open-label, dose-finding study. Five cohorts of patients received a weekly antibody monotherapy with a dose-range from 0.1 to 0.8 mg/kg. Itolizumab showed a good safety profile, with no severe or serious adverse events reported so far. No signs or symptoms associated with immunosuppression were observed in the study. Objective clinical responses were achieved in more than 80% of patients after treatment completion, and these responses tend to be sustained afterwards. This clinical study constitutes the first evidence of the safety and positive clinical effect of a monotherapy using an anti-CD6 antibody in patients with rheumatoid arthritis.

Background

IL-31 is a novel cytokine that has been implicated in allergic diseases such as atopic dermatitis and more recently asthma. While IL-31 has been well studied in skin conditions such as atopic dermatitis, little is known about the role IL-31 plays in asthma and specifically the differentiation process of the bronchial epithelium, which is central to the pathogenesis of allergic asthma.

Methods

We examined the effects of IL-13 (20 ng/ml), IL-31 (20 ng/ml) and an IL-13/IL-31 combination stimulation (20 ng/ml each) on the in vitro mucociliary differentiation of paediatric bronchial epithelial cells (PBECs) from healthy patients (n=6). IL-31 receptor (IL-31-RA) expression, markers of differentiation (goblet and ciliated cells), transepithelial electrical resistance (TEER), quantification of goblet and ciliated cells, real time PCR for MUC5AC, ELISA for VEGF, EGF and MCP-1 (CCL-2) and ELISA for MUC5AC were assessed.

Results

We found that well-differentiated PBECs expressed IL-31-RA however it's expression did not increase upon stimulation with IL-31 or either of the other treatments. TEER indicated good formation of tight junctions which was found to be similar across all treatment groups (p=0.9). We found that IL-13 alone significantly reduced the number of ciliated cells compared with unstimulated (IL-13 stimuation: mean=4.8% (SD=2.5); unstimulated: mean=15.9%, (SD=7.4), p<0.01). IL-31 stimulation alone had no effect on ciliated cells whereas the IL-13/IL-31 combination stimulation significantly reduced the number of ciliated cells compared with control (IL-13/IL-31 combination: mean=5.1% (SD=4.6); unstimulated: mean=15.9%, (SD=7.4), p<0.01). We did not find that the combination of IL-13 and IL-31 had any additional effects to that of IL-13 alone. MUC5AC mRNA and secreted mucin was found in similar levels between unstimulated and all treatments, however IL-13 increased levels of MUC5AC mRNA by a factor of 2.84, albeit not significantly, compared with unstimulated cultures (IL-13 stimulation: mean=2.84 (SD=3.79); unstimulated: mean=1.0).

Conclusions

IL-31RA receptor is present on well-differentiated paediatric bronchial epithelial cells. IL-31 does not exhibit any detrimental effects on mucociliary differentiation. IL-31 does not appear to have a synergistic effect when combined in culture with IL-13, in the differentiation process.

Bone marrow biopsy is useful for diagnosis of hematopoietic diseases. We have recently reported that bone marrow biopsy from the flipper might be useful for diagnosis of hematopoietic diseases in dolphins. In this study, to demonstrate whether biopsy from the flipper is useful for clinical diagnosis, we investigated the gene expression profiles and proliferation and differentiation of bone marrow mononuclear cell (BMMC) isolated from the humeral bone marrow of bottlenose dolphins. BMMC exhibited gene expression profiles considered to be characteristic of hematopoietic cells. Similarly, a colony forming unit assay showed that dolphin BMMC possessed vigorous colony forming ability. The proliferation of hematopoietic progenitor cells resulted in the formation of three types of colonies, containing neutrophils, monocytes/macrophages and eosinophils with or without megakaryocytes, all of which could be identified based on the morphological characteristics and gene expression profiles typically associated with hematopoietic markers. Thus, dolphin BMMCs from humeral bone marrow contain many hematopoietic progenitor cells, and bone marrow biopsy from the flipper is suggested useful for clinical diagnosis for the dolphins.