Expression Levels Of Immune Genes Research Articles

Abstract B62: Immune gene expression profiling identifies predictors of relapse in childhood acute myeloid leukemia

Abstract Tumor phenotypes are dictated not only by the neoplastic cell component, but also by the tumor microenvironment (TME), which includes immune and inflammatory cells. Acute myeloid leukemia (AML) is the second most common leukemia of childhood. Although intensive multi-agent chemotherapy in conjunction with improved supportive care has increased survival rates to 70%, 30-40% of children with AML relapse and only one-third of them will survive to adulthood. Investigation of new therapeutic strategies for high-risk AML, including immunotherapy, remains a priority and is being actively pursued. Importantly, AML-induced immune suppression poses a fundamental barrier to successful immune-based interventions. We previously showed that in vitro treatment of primary AML cells with interferon (IFN)-γ induces functional indoleamine 2,3-dioxygenase-1 (IDO1), a molecule with potent immunosuppressive properties, in 50% of unselected cases (IFN-γ responders). With a median follow-up of 8 years, IFN-γ responders experienced a significantly shorter event-free survival and overall survival (OS). Herein, we aimed to get insights into the immune landscape of childhood AML using multi-scale immune profiling strategies with the aim to identify molecular circuits that can be targeted to revert leukemia-induced immune dysfunction and improve clinical outcome. We employed a novel high-throughput digital platform, the nCounter system (nanoString Technologies, Seattle, USA), and Optimized Multi-color Immuno-phenotyping Panels (OMIPs) to comprehensively characterize the bone marrow immune infiltrate in 34 children diagnosed with non-promyelocytic AML (17 males, 17 females; median age at diagnosis=10 years; 28 de novo AML, 4 infant leukemia, 1 secondary AML, 1 congenital leukemia; 7 patients with favorable-risk cytogenetics, 21 patients with intermediate-risk cytogenetics and 6 patients with unfavorable-risk cytogenetics). The RNA Pan-Cancer Immune Profiling Panel, which includes 109 cell surface markers for 24 immune cell types, 30 cancer testis antigens, and >500 immune response genes, allowed us to measure immune gene expression levels on the clinic-ready nCounter® FLEX platform (nanoString Technologies). Transcriptomic data were normalized and analyzed using the nSolver software package. Relapse-free survival (RFS) and OS were selected as covariates. For immune phenotyping studies, viable bone marrow mononuclear cells were labeled with fluorochrome-conjugated antibodies and then analyzed on a 10-color Gallios flow cytometer (Beckman Coulter Life Sciences, Buckinghamshire, UK) with standard settings. Hierarchical clustering of immune gene expression data highlighted patient subgroups with heightened expression of T-cell and natural killer (NK)-cell function genes, as well as Toll-like receptor (TLR) genes, interleukin genes and tumor necrosis factor (TNF) family genes. Patients with high levels of CD8A mRNA also expressed IFNG, CXCL9, CXCL10, FOXP3 and negative checkpoints, including LAG3, CTLA4, IDO1 and CD279 (PD-L1), consistent with T-cell inflamed phenotypes that might underpin the establishment of adaptive immune resistance mechanisms of immune escape. In-depth phenotyping studies showed higher percentages of bone marrow-resident naïve B cells, plasmablasts, intermediate and non-conventional monocytes, plasmacytoid dendritic cells (DCs) and CXCR3-expressing Th1 cells at diagnosis compared with complete remission (CR). By contrast, both type 1 and type 2 myeloid DCs were more represented in the TME of patients with AML in CR. The frequencies of innate lymphoid cells (ILCs) and Vγ9+Vδ2+ T cells were not significantly different when comparing diagnosis and CR samples. Relapses occurred in 71.4% of children with “inflamed” AML compared with 28.6% of patients with “non-inflamed” AML (p=0.012; two-sided Fisher’s exact test). Importantly, RFS was remarkably shorter in patients with inflamed compared with non-inflamed AML (median RFS=394 days vs. undefined; hazard ratio = 0.266; 95% CI=0.11-0.64; p=0.0039, log-rank test). A non-significant association with OS was also observed. In conclusion, inflamed or “hot” AMLs are associated with shorter RFS and might be amenable to immunotherapy approaches tailored to the bone marrow TME, including PD-1/PD-L1 blockade and/or small-molecule IDO1 inhibitors. Grant support: Roger Counter Foundation, Dorset, UK and Qatar National Research Fund (grant #NPRP8-2297-3-494). Citation Format: Jayakumar Vadakekolathu, Gemma A. Foulds, Tasleema Patel, Stephen Reeder, Alan Graham Pockley, Sarah K. Tasian, Sergio Rutella. Immune gene expression profiling identifies predictors of relapse in childhood acute myeloid leukemia [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2017 Oct 1-4; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2018;6(9 Suppl):Abstract nr B62.

Expression of Macrobrachium rosenbergii lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP) in Saccharomyces cerevisiae and evaluation of its immune function

Pattern recognition proteins (PRPs) activate the innate immune system in invertebrates, and lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP) is an important PRP with various biological functions. Here, the open reading frame (ORF) of Macrobrachium rosenbergii LGBP (MrLGBP) was cloned into plasmid vector pHAC181, then integrated into downstream of the GAL1 promoter of Saccharomyces cerevisiae strain GAL1-ScRCH1 via homologous recombination, followed by its expression in the yeast eukaryotic system. The resulting recombinant LGBP contained a 3 × HA-tag at its C terminus and had a molecular weight of about 45 kDa, as evaluated by western blot analysis. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were ranged from 0.340 to 0.802 and 1.189–1.810 μM, respectively. The recombinant MrLGBP protein agglutinated almost all tested bacteria except Bacillus thuringiensis and Staphylococcus aureus. These results revealed that this recombinant protein exhibited antimicrobial activity against some Gram-positive and Gram-negative bacteria. M. rosenbergii prawns were fed with the recombinant yeast strain MrLGBP for 1 month and challenged with the most common crustacean pathogen, Vibrio parahaemolyticus. These prawns showed lower mortality and higher enzymatic activity and expression levels of immunity genes than did the control groups. All these results suggest that MrLGBP may play important roles in the innate immunity of crustaceans, and recombinant strain S. cerevisiae MrLGBP may be useful for the development of an effective immune feed additive in the future.

Assortment of Flowering Time and Immunity Alleles in Natural Arabidopsis thaliana Populations Suggests Immunity and Vegetative Lifespan Strategies Coevolve.

The selective impact of pathogen epidemics on host defenses can be strong but remains transient. By contrast, life-history shifts can durably and continuously modify the balance between costs and benefits of immunity, which arbitrates the evolution of host defenses. Their impact on the evolutionary dynamics of host immunity, however, has seldom been documented. Optimal investment into immunity is expected to decrease with shortening lifespan, because a shorter life decreases the probability to encounter pathogens or enemies. Here, we document that in natural populations of Arabidopsis thaliana, the expression levels of immunity genes correlate positively with flowering time, which in annual species is a proxy for lifespan. Using a novel genetic strategy based on bulk-segregants, we partitioned flowering time-dependent from -independent immunity genes and could demonstrate that this positive covariation can be genetically separated. It is therefore not explained by the pleiotropic action of some major regulatory genes controlling both immunity and lifespan. Moreover, we find that immunity genes containing variants reported to impact fitness in natural field conditions are among the genes whose expression covaries most strongly with flowering time. Taken together, these analyses reveal that natural selection has likely assorted alleles promoting lower expression of immunity genes with alleles that decrease the duration of vegetative lifespan in A. thaliana and vice versa. This is the first study documenting a pattern of variation consistent with the impact that selection on flowering time is predicted to have on diversity in host immunity.

Dietary olive leaf (Olea europea L.) extract alters some immune gene expression levels and disease resistance to Yersinia ruckeri infection in rainbow trout Oncorhynchus mykiss

The aim for the present study was to investigate the effects of olive leaf (Olea europea L.) extract (OLE) on the control of Yersinia ruckeri infection in rainbow (Oncorhynchus mykiss) trout and to assess the impact on the expression of immune-related genes in the spleen and serum biochemical parameters of rainbow trout. Five experimental diets were prepared by adding 0.0%, 0.1%, 0.25%, 0.50% and 1.0% of OLE. Each diet was fed to triplicate groups of fish (mean body weight 51.22 ± 3.04 g) twice a day (at 09:00 and 17:00 h) for 60 days. The dietary supplementation of OLE did not affect growth performance and feed utilization (P > 0.05). Major changes due to graded levels of OLE in the diets were observed in blood biochemical parameters (P < 0.05). TNFα, IL1-β and IL-8 gene expressions were significanlty up-regulated in OLE 0.1% group compared with others (P < 0.05). Also, diet supplemented with OLE reduced mortality in rainbow trout fed with OLE 0.1% added diet. Present study suggests that OLE especially at 0.1% added feed may effectivelly enhance the serum biochemical parameters, survival rate and immune gene expression in rainbow trout.

Alterations in non-specific immune responses, antioxidant capacities and expression levels of immunity genes in Labeo rohita fed with graded level of carbohydrates

A 45-day feeding trial was conducted to study the effect of feeding graded level of gelatinized starch (GS) on stress parameters, growth and immunity of Labeo rohita. Fish were fed with four semi-purified diets containing 30% crude protein with graded level of gelatinized starch, 30% (T1), 35% (T2), 40% (T3) and 45% (T4). The results exhibited higher weight gain % (WG), specific growth rate (SGR) and protein efficiency ratio (PER) in 45% GS fed group (T4) with significantly (p<0.05) lowest feed conversion ratio (FCR). The blood NBT and serum complement 3 (C3), serum protein, albumin and globulin contents were increased with the increase in GS level in the diet. The SOD, catalase, alanine transaminase (ALT) and aspartate transaminase (AST) in liver increased significantly (p>0.05) with the increasing level of GS in the diet. In addition, the high carbohydrate level (CHO) 40% and 45% significantly upregulated the mRNA level of immune related genes like Nuclear Factor Kappa B (NFkB) and Interleukin (IL8) in both liver and kidney. Furthermore, highest percentage of survival was found in T4 group after challenged with Aeromonas hydrophila followed by T3 group. The results of the present study suggest that Labeo rohita fingerlings can utilize the high digestible carbohydrate upto 45% without affecting growth and immunity.

Chinese Sacbrood virus infection in Asian honey bees (Apis cerana cerana) and host immune responses to the virus infection.

Chinese Sacbrood virus (CSBV) is a positive-stranded RNAvirus that infects both the European honey bee (Apis mellifera) and the Asian honey bee (A. cerana). However, CSBV has much more devastating effects on Asian honey bees than on European honey bees, posing a serious threat to the agricultural and natural ecosystems that rely on A. cerana for pollination service. Using quantitative RT-PCR method, we conducted studies to examine the CSBV infection in Asian honey bee colonies and immune responses of individual bees in response to CSBV infection. Our study showed that CSBV could cause infection in different developmental stages of workers including eggs, larvae, pupae, newly emerged workers, and foraging workers. In addition, evaluating the tissue tropism and transmission of CSBV in infected bees showed that CSBV was detected in the ovaries, spermatheca, and feces of queens as well as semen of drones of the same colonies, suggesting an existence of vertical transmission of CSBV in Asian honey bees. Further, the detection of CSBV in colony food suggests that healthy bees could pick the infection by the virus-contaminated food, and therefore, a possible existence of a food-borne transmission pathway of CSBV in Asian bee colonies. The expression analysis of transcripts (defensin, abaecin, apidaecin, and hymenoptaecin) involving innate antiviral immune pathways showed that CSBV infection could induce significant immune responses in infected bees. However, the immune responses to CSBV infection varied among different development stages with eggs exhibiting the lowest level of immune expression and forager workers exhibiting the highest level of immune gene expression. The results obtained in the study yield important insights into the mechanisms underlying disease pathogenesis of CSBV infections in Asian honey bees and provide valuable information for a rational design of disease control measures.

Endogenous egg immune defenses in the yellow mealworm beetle (Tenebrio molitor)

In order to survive microbe encounters, insects rely on both physical barriers as well as local and systemic immune responses. Most research focusses on adult or larval defenses however, whereas insect eggs are also in need of protection. Lately, the defense of eggs against microbes has received an increasing amount of attention, be it through endogenous egg defenses, trans-generational immune priming (TGIP) or parental investment. Here we studied the endogenous immune response in eggs and adults of Tenebrio molitor. We show that many immune genes are induced in both adults and eggs. Furthermore, we show that eggs reach comparable levels of immune gene expression as adults. These findings show that the eggs of Tenebrio are capable of an impressive endogenous immune response, and indicate that such inducible egg defenses are likely common in insects.

No evidence of local adaptation of immune responses to Gyrodactylus in three-spined stickleback (Gasterosteus aculeatus)

Parasitism represents one of the most widespread lifestyles in the animal kingdom, with the potential to drive coevolutionary dynamics with their host population. Where hosts and parasites evolve together, we may find local adaptation. As one of the main host defences against infection, there is the potential for the immune response to be adapted to local parasites. In this study, we used the three-spined stickleback and its Gyrodactylus parasites to examine the extent of local adaptation of parasite infection dynamics and the immune response to infection. We took two geographically isolated host populations infected with two distinct Gyrodactylus species and performed a reciprocal cross-infection experiment in controlled laboratory conditions. Parasite burdens were monitored over the course of the infection, and individuals were sampled at multiple time points for immune gene expression analysis. We found large differences in virulence between parasite species, irrespective of host, and maladaptation of parasites to their sympatric host. The immune system responded to infection, with a decrease in expression of innate and Th1-type adaptive response genes in fish infected with the less virulent parasite, representing a marker of a possible resistance mechanism. There was no evidence of local adaptation in immune gene expression levels. Our results add to the growing understanding of the extent of host-parasite local adaptation, and demonstrate a systemic immune response during infection with a common ectoparasite. Further immunological studies using the stickleback-Gyrodactylus system can continue to contribute to our understanding of the function of the immune response in natural populations.

Abstract 2651: Clinical activity and immune correlates from a phase Ib study evaluating atezolizumab (anti-PDL1) in combination with FOLFOX and bevacizumab (anti-VEGF) in metastatic colorectal carcinoma

Abstract Genetic and epigenetic alterations can distinguish cancer cells from their normal counterparts, allowing tumors to be recognized as foreign by the immune system. The immune system's ability to detect and destroy these abnormal cells is the foundation of cancer immunotherapy. In order for this to occur immune cells must traffic and persist in the tumors. Programmed death-ligand 1 (PD-L1; also called B7-H1 or CD274), which is expressed on many cancer and tumor-infiltrating immune cells, plays an important part in blocking immune-mediated tumor cell destruction by binding B7.1 (CD80) and programmed death-1 (PD-1), which is a negative regulator of T-lymphocyte activation. PD-L1 blockade has previously been shown to increase CD8+ T cell infiltration and PD-L1 protein levels, as well as the expression levels of immune genes in tumors. Vascular endothelial growth factor A (VEGF-A) is a secreted factor that specifically acts on endothelial cells to stimulate angiogenesis and has also been shown to exert immunosuppressive effects. Although some cytotoxic agents have been proposed to induce immunogenic cell death, the effects of chemotherapy and anti-angiogenic therapy on the tumor immune milieu have not been extensively studied. This study was designed to evaluate the safety, activity and biomarkers of combined FOLFOX treatment combined with PD-L1 and VEGF-A inhibition in 1L colorectal (CRC) patients using the humanized antibodies atezolizumab (anti-PD-L1) and bevacizumab (anti-VEGF-A), respectively. RECIST (v1.1) responses by the cutoff date of 09/01/2015 were observed in 52% (95% CI 30.6-73.2) of the patients (n = 23) with a median progression free survival of 14.1 months (95% CI 8.7-17.1) and a median duration of response of 11.4 months (95% CI 7.6-15.9). No unexpected toxicities were observed. We found that CD8+ T cells and PD-L1 expression by IHC were increased in tumors following administration of FOLFOX alone as well as after combined administration of FOLFOX, atezolizumab and bevacizumab. Elevations in cytotoxic T-cell signatures (e.g. CD8A, IFNγ, GZMB, EOMES) with treatment were also noted in several of the patient tumors. Patients with elevations in tumor-infiltrating CD8+ T cells consistent with increased expression of cytotoxic T-cell signatures and PD-L1 exhibited sustained responses or prolonged disease control. These data suggest that the combination of FOLFOX, atezolizumab, and bevacizumab promote immune-related activity in CRC potentially resulting in enhanced efficacy. Citation Format: Jeffrey Wallin, Michael J. Pishvaian, Genevive Hernandez, Mahesh Yadav, Suchit Jhunjhunwala, Lelia Delamarre, Xian He, John Powderly, Christopher Lieu, S Gail Eckhardt, Herbert Hurwitz, Howard S. Hochster, Janet Murphy, Vincent Leveque, Edward Cha, Roel Funke, Daniel Waterkamp, Priti Hegde, Johanna Bendell. Clinical activity and immune correlates from a phase Ib study evaluating atezolizumab (anti-PDL1) in combination with FOLFOX and bevacizumab (anti-VEGF) in metastatic colorectal carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2651.

Effects of Imidacloprid and Varroa destructor on survival and health of European honey bees, Apis mellifera.

There has been growing concern over declines in populations of honey bees and other pollinators which are a vital part to our food security. It is imperative to identify factors responsible for accelerated declines in bee populations and develop solutions for reversing bee losses. While exact causes of colony losses remain elusive, risk factors thought to play key roles are ectoparasitic mites Varroa destructor and neonicotinoid pesticides. The present study aims to investigate effects of a neonicotinoid pesticide Imidacloprid and Varroa mites individually on survivorship, growth, physiology, virus dynamics and immunity of honey bee workers. Our study provides clear evidence that the exposure to sublethal doses of Imidacloprid could exert a significantly negative effect on health and survival of honey bees. We observed a significant reduction in the titer of vitellogenin (Vg), an egg yolk precursor that regulates the honey bees development and behavior and often are linked to energy homeostasis, in bees exposed to Imidacloprid. This result indicates that sublethal exposure to neonicotinoid could lead to increased energy usage in honey bees as detoxification is a energy-consuming metabolic process and suggests that Vg could be a useful biomarker for measuring levels of energy stress and sublethal effects of pesticides on honey bees. Measurement of the quantitative effects of different levels of Varroa mite infestation on the replication dynamic of Deformed wing virus (DWV), an RNA virus associated with Varroa infestation, and expression level of immune genes yields unique insights into how honey bees respond to stressors under laboratory conditions.

Dietary Effect of Lonicera japonica on Immune Expression in Olive Flounder Paralichthys olivaceus, Challenged with Vibrio anguillarum

Respiratory burst, lysozyme, phagocytic activities, and immune gene expression levels were assessed in olive flounder (Paralichthys olivaceus, 10.52±2.5 g) fed with 0%, 0.025%, 0.05%, 0.1%, 0.2%, and 0.4% Lonicera japonica leaf powder (LjLP) for four weeks. All flounder fish fed LjLP showed significantly increased respiratory burst, lysozyme and phagocytic activity. Total immunoglobulin levels in LjLP diet fed fish groups were higher than in fish fed the basal diet (BD). In flounder fed LjLP, immune gene expression and antioxidant activity were significantly enhanced after 4 weeks of culture. One week following a challenge with Vibrio anguillarum, fish fed with different concentrations of LjLP showed decreased cumulative mortality and enhanced immunity all compared to the BD diet group. Our findings have shown that Lonicera japonica leaf powder enhanced immune response and resistance to V. anguillarum infection in olive flounder.

Extracting tumor tissue immune status from expression profiles: correlating renal cancer prognosis with tumor-associated immunome.

Investigating the expression of genes in cancer-associated immune cells (immunome) is imperative for prognosis prediction. However, evaluating the expression of immune-associated genes within cancer biopsy is subject to significant inconsistencies related to the sampling methodology. Here, we present immFocus, a method for extracting immune signals from total RNA sequencing of tumor biopsies, intended for immunity depiction and prognosis evaluation. It is based on reducing the variation which biopsy preparation adds to the apparent expression levels of immune genes. We employed immFocus to normalize gene expression with an immune index using data obtained from renal clear cell carcinoma biopsies. Genes that became less variable due to normalization were found to be preferentially immune-related. Moreover, immune-related genes tended to become more prognostic due to the normalization. These results demonstrate, for the first time, that whole transcriptome sequencing can be used for interrogation of a cancer immunome and for advancing immune-based prognosis.

Elevated seawater temperatures have a limited impact on the coral immune response following physical damage

Recurrent disturbances on coral reefs that cause injuries, like predation and storm damage, and elevated seawater temperatures reduce coral fitness and immunocompetence. An effective immune response is essential to prevent disease and enhance colony survival. To evaluate how elevated seawater temperatures affect the coral immune response following injury, fragments of Acropora aspera were exposed to ambient (27–29°C) or elevated (32–33.5°C) seawater temperatures for 8 days and subsequently experimentally injured. Expression patterns for 15 immune genes 24 h post-injury revealed that most genes involved in the Toll-like receptor pathway were unaffected by elevated seawater temperatures. Exceptions to this pattern were cFos and cJun, which were upregulated and likely played a role in repair processes, and TRAF-6 and NFκB, which were downregulated suggesting reduced immune function. Components of the complement system were upregulated (millectin, C3) or downregulated (Bf, Tx60, apextrin) in corals at high temperatures. However, corals that also sustained injury, showed normal Tx60 and apextrin expression, suggesting roles in the wounding response. Overall, basal expression levels of immune genes are sufficient to mount a response to injury in the short term, and the immune response of A. aspera following injury is not significantly affected by minor elevations in seawater temperatures.

Immune gene expressions in grouper larvae (Epinephelus coioides) induced by bath and oral vaccinations with inactivated betanodavirus

Nervous necrosis virus (NNV) has caused mass mortality in many mariculture fish species. Bath vaccination of inactivated NNV and oral immunization of recombinant NNV coat protein are reported to protect grouper larvae against NNV infection. However, the information of immune gene expression in grouper larvae (Epinephelus coioides) after bath and oral immunizations is still limited. In this study, grouper larvae were respectively bath- and orally immunized with binary ethylenimine (BEI)-inactivated NNV, and the expression levels of immune genes were analyzed. Significant gene expressions of IL-1β, Mx, MHC-I, MHC-II, CD8α, IgM and IgT were observed in bath- and orally immunized fish 1–4 weeks post immunization (wpi). Particularly, the up-regulation of IL-1β and Mx gene expression lasted for 4 weeks. The IgT gene expression in gill was only induced by bath immunization, while that in gut was only stimulated by oral immunization. Both immunizations elicited MHC-I and CD8α gene expression relative to cellular immunity. Furthermore, NNV RNA genome, which was detected in inactivated NNV, could induce Mx gene expression in grouper brain (GB) cells, indicating that NNV RNA genome could be recognized by pathogen-recognition receptors (PRRs). In summary, bath and oral vaccinations with BEI-inactivated NNV triggered the gene expression of not only humoral immunity but also cellular immunity.

Comparative study of immune responses in the deep-sea hydrothermal vent mussel Bathymodiolus azoricus and the shallow-water mussel Mytilus galloprovincialis challenged with Vibrio bacteria

The deep-sea hydrothermal vent mussel Bathymodiolus azoricus and the continental European coast Mytilus galloprovincialis are two bivalves species living in highly distinct marine habitats. Mussels are filter-feeding animals that may accumulate rapidly bacteria from the environment. Contact with microorganism is thus inevitable during feeding processes where gill tissues assume a strategic importance at the interface between the external milieu and the internal body cavities promoting interactions with potential pathogens during normal filtration and a constant challenge to their immune system.In the present study B. azoricus and M. galloprovincialis were exposed to Vibrio alginolyticus, Vibrio anguillarum and Vibrio splendidus suspensions and to a mixture of these Vibrio suspensions, in order to ascertain the expression level of immune genes in gill samples, from both mussel species. The immune gene expressions were analyzed by means of quantitative-Polymerase Chain Reaction (qPCR). The gene expression results revealed that these bivalve species exhibit significant expression differences between 12 h and 24 h post-challenge times, and between the Vibrio strains used. V. splendidus induced the strongest gene expression level in the two bivalve species whereas the NF-κB and Aggrecan were the most significantly differentially expressed between the two mussel species. When comparing exposure times, both B. azoricus and M. galloprovincialis showed similar percentage of up-regulated genes at 12 h while a marked increased of gene expression was observed at 24 h for the majority of the immune genes in M. galloprovincialis. This contrasts with B. azoricus where the majority of the immune genes were down-regulated at 24 h. The 24 h post-challenge gene expression results clearly bring new evidence supporting time-dependent transcriptional activities resembling acute phase-like responses and different immune responses build-up in these two mussel species when challenged with Vibrio bacteria.High Pressure Liquid Chromatography (HPLC)-Electrospray ionization mass spectrometry (ESI-MS/MS) analyses resulted in different peptide sequences from B. azoricus and M. galloprovincialis gill tissues suggesting that naïve animals present differences, at the protein synthesis level, in their natural environment. B. azoricus proteins sequences, mostly of endosymbiont origin, were related to metabolic, energy production, protein synthesis processes and nutritional demands whereas in M. galloprovincialis putative protein functions were assumed to be related to structural and cellular integrity and signaling functions.

Finding immune gene expression differences induced by marine bacterial pathogens in the Deep-sea hydrothermal vent mussel &amp;lt;i&amp;gt;Bathymodiolus azoricus&amp;lt;/i&amp;gt;

Abstract. The deep-sea hydrothermal vent mussel Bathymodiolus azoricus lives in a natural environment characterised by extreme conditions of hydrostatic pressure, temperature, pH, high concentrations of heavy metals, methane and hydrogen sulphide. The deep-sea vent biological systems represent thus the opportunity to study and provide new insights into the basic physiological principles that govern the defense mechanisms in vent animals and to understand how they cope with microbial infections. Hence, the importance of understanding this animal's innate defense mechanisms, by examining its differential immune gene expressions toward different pathogenic agents. In the present study, B. azoricus mussels were infected with single suspensions of marine bacterial pathogens, consisting of Vibrio splendidus, Vibrio alginolyticus, or Vibrio anguillarum, and a pool of these Vibrio bacteria. Flavobacterium suspensions were also used as a non-pathogenic bacterium. Gene expression analyses were carried out using gill samples from infected animals by means of quantitative-Polymerase Chain Reaction aimed at targeting several immune genes. We also performed SDS-PAGE protein analyses from the same gill tissues. We concluded that there are different levels of immune gene expression between the 12 h to 24 h exposure times to various bacterial suspensions. Our results from qPCR demonstrated a general pattern of gene expression, decreasing from 12 h over 24 h post-infection. Among the bacteria tested, Flavobacterium is the bacterium inducing the highest gene expression level in 12 h post-infections animals. The 24 h infected animals revealed, however, greater gene expression levels, using V. splendidus as the infectious agent. The SDS-PAGE analysis also pointed at protein profile differences between 12 h and 24 h, particularly evident for proteins of 18–20 KDa molecular mass, where most dissimilarity was found. Multivariate analyses demonstrated that immune genes, as well as experimental infections, clustered in discrete groups in accordance with the gene expression patterns induced by bacterial pathogens.

Interactions between human immunodeficiency virus (HIV)-1 Vpr expression and innate immunity influence neurovirulence

BackgroundViral diversity and abundance are defining properties of human immunodeficiency virus (HIV)-1's biology and pathogenicity. Despite the increasing availability of antiretroviral therapy, HIV-associated dementia (HAD) continues to be a devastating consequence of HIV-1 infection of the brain although the underlying disease mechanisms remain uncertain. Herein, molecular diversity within the HIV-1 non-structural gene, Vpr, was examined in RNA sequences derived from brain and blood of HIV/AIDS patients with or without HIV-associated dementia (HAD) together with the ensuing pathobiological effects.ResultsCloned brain- and blood-derived full length vpr alleles revealed that amino acid residue 77 within the brain-derived alleles distinguished HAD (77Q) from non-demented (ND) HIV/AIDS patients (77R) (p < 0.05) although vpr transcripts were more frequently detected in HAD brains (p < 0.05). Full length HIV-1 clones encoding the 77R-ND residue induced higher IFN-α, MX1 and BST-2 transcript levels in human glia relative to the 77Q-HAD encoding virus (p < 0.05) but both viruses exhibited similar levels of gene expression and replication. Myeloid cells transfected with 77Q-(pVpr77Q-HAD), 77R (pVpr77R-ND) or Vpr null (pVpr(-))-containing vectors showed that the pVpr77R-ND vector induced higher levels of immune gene expression (p < 0.05) and increased neurotoxicity (p < 0.05). Vpr peptides (amino acids 70-96) containing the 77Q-HAD or 77R-ND motifs induced similar levels of cytosolic calcium activation when exposed to human neurons. Human glia exposed to the 77R-ND peptide activated higher transcript levels of IFN-α, MX1, PRKRA and BST-2 relative to 77Q-HAD peptide (p < 0.05). The Vpr 77R-ND peptide was also more neurotoxic in a concentration-dependent manner when exposed to human neurons (p < 0.05). Stereotaxic implantation of full length Vpr, 77Q-HAD or 77R-ND peptides into the basal ganglia of mice revealed that full length Vpr and the 77R-ND peptide caused greater neurobehavioral deficits and neuronal injury compared with 77Q-HAD peptide-implanted animals (p < 0.05).ConclusionsThese observations underscored the potent neuropathogenic properties of Vpr but also indicated viral diversity modulates innate neuroimmunity and neurodegeneration.

Post-mating disparity between potential and realized immune response inDrosophila melanogaster

Reproductive costs are an essential component of evolutionary theory. For instance, an increase in reproduction is generally coupled with a decrease in immunocompetence shortly after mating. However, recent work in Drosophila melanogaster suggests that the potential to mount an immune response, as measured by the levels of immune gene expression, increases after mating. These data are in contrast to previous studies, which suggest that mating can reduce a fly's ability to survive an actual bacterial challenge (realized immunity). This pattern may be driven by some aspect of mating, independent of resource limitation, which reduces immune function by inhibiting the effective deployment of immune gene products. Though several studies have examined both the potential and the realized immunity after mating, none have examined these immune measures simultaneously. Here, we examined the link between the potential and the realized immunity in a sterile mutant of D. melanogaster. Shortly after mating, we found that female immune gene expression was high, but survival against infection was low. Surprisingly, this pattern was reversed within 24 h. Thus, estimates of immunity based on gene expression do not appear to reflect an actual ability to defend against pathogens in the hours following copulation. We discuss the possible mechanisms that may account for this pattern.