Transcriptional profiling of TLR-4/7/8-stimulated guinea pig splenocytes and whole blood by bDNA assay

cAMP-specific phosphodiesterase 8A and 8B isoforms are differentially expressed in human testis and Leydig cell tumor

Cyclic adenosine monophosphate/Protein kinase A (cAMP/PKA) signaling pathway is the master regulator of endocrine tissue function. The level, compartmentalization and amplitude of cAMP response are finely regulated by phosphodiesterases (PDEs). PDE8 is responsible of cAMP hydrolysis and its expression has been characterized in all steroidogenic cell types in rodents including adrenal and Leydig cells in rodents however scarce data are currently available in humans. Here we demonstrate that human Leydig cells express both PDE8A and PDE8B isoforms. Interestingly, we found that the expression of PDE8B but not of PDE8A is increased in transformed Leydig cells (Leydig cell tumors-LCTs) compared to non-tumoral cells. Immunofluorescence analyses further reveals that PDE8A is also highly expressed in specific spermatogenic stages. While the protein is not detected in spermatogonia it accumulates nearby the forming acrosome, in the trans-Golgi apparatus of spermatocytes and spermatids and it follows the fate of this organelle in the later stages translocating to the caudal part of the cell. Taken together our findings suggest that 1) a specific pool(s) of cAMP is/are regulated by PDE8A during spermiogenesis pointing out a possible new role of this PDE8 isoform in key events governing the differentiation and maturation of human sperm and 2) PDE8B can be involved in Leydig cell transformation.

The complexities and challenges of preventing and treating nontuberculous mycobacterial diseases

Seemingly innocuous nontuberculous mycobacteria (NTM) species, classified by their slow or rapid growth rates, can cause a wide range of illnesses, from skin ulceration to severe pulmonary and disseminated disease. Despite their worldwide prevalence and significant disease burden, NTM do not garner the same financial or research focus as Mycobacterium tuberculosis. In this review, we outline the most abundant of over 170 NTM species and inadequacies of diagnostics and treatments and weigh the advantages and disadvantages of currently available in vivo animal models of NTM. In order to effectively combat this group of mycobacteria, more research focused on appropriate animal models of infection, screening of chemotherapeutic compounds, and development of anti-NTM vaccines and diagnostics is urgently needed.

Prognostic value of a 25-gene assay in patients with gastric cancer after curative resection

This study aimed to develop and validate a practical, reliable assay for prognosis and chemotherapy benefit prediction compared with conventional staging in Gastric cancer (GC). Twenty-three candidate genes with significant correlation between quantitative hybridization and microarray results plus 2 reference genes were selected to form a 25-gene prognostic classifier, which can classify patients into 3 distinct groups of different risk of mortality obtained by analyzing microarray data from 78 frozen tumor specimens. The 25-gene assay was associated with overall survival in both training (P = 0.017) and testing cohort (P = 0.005) (462 formalin-fixed paraffin-embedded samples). The risk prediction in stages I + II is significantly better than that in stages III. Analysis demonstrated that this 25-gene signature is an independent prognostic predictor and show higher prognostic accuracy than conventional TNM staging in early stage patients. Moreover, only high-risk patients in stage I + II were found benefit from adjuvant chemotherapy (P = 0.043), while low-risk patients in stage III were not found benefit from adjuvant chemotherapy. In conclusion, our results suggest that this 25-gene assay can reliably identify patients with different risk for mortality after surgery, especially for stage I + II patients, and might be able to predict patients who benefit from chemotherapy.

Glyceraldehyde-3-phosphate dehydrogenase is an inappropriate housekeeping gene for normalising gene expression in sepsis

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has long been used as a default reference gene in quantitative mRNA profiling experiments. However, its expression reportedly varies in response to a range of pathophysiological variables (inflammation, oxidative stress, hyperinsulinaemia, hypoxia) which feature prominently in sepsis. We therefore assessed the applicability of using GAPDH as a reference gene for expression studies in sepsis compared to other housekeeping genes (succinate dehydrogenase complex subunit A (SDHA), hypoxanthine phosphoribosyltransferase (HPRT)-1). Severe sepsis resulted in a 42.4-fold increase in median GAPDH expression (P<0.001), whereas median HPRT expression was raised more modestly (2.9-fold; P<0.001), and there was no significant difference in SDHA expression between sepsis and control patients. HPRT was identified by NormFinder to be the most stably expressed single gene. In order to assess the impact of this variability on data interpretation, interleukin (IL)-10 expression was normalised separately to GAPDH and to the geometric mean of HPRT and SDHA. In the former case, there was no significant difference in IL-10 expression between controls and septic patients, whilst in the latter, a significant 8.5-fold increase in median IL-10 expression was noted (P<0.001). GAPDH is thus an unreliable housekeeping gene for normalising gene expression in sepsis which should be replaced by alternative, validated reference genes.

Establishment of a new quality control and vaccine safety test for influenza vaccines and adjuvants using gene expression profiling

We have previously identified 17 biomarker genes which were upregulated by whole virion influenza vaccines, and reported that gene expression profiles of these biomarker genes had a good correlation with conventional animal safety tests checking body weight and leukocyte counts. In this study, we have shown that conventional animal tests showed varied and no dose-dependent results in serially diluted bulk materials of influenza HA vaccines. In contrast, dose dependency was clearly shown in the expression profiles of biomarker genes, demonstrating higher sensitivity of gene expression analysis than the current animal safety tests of influenza vaccines. The introduction of branched DNA based-concurrent expression analysis could simplify the complexity of multiple gene expression approach, and could shorten the test period from 7 days to 3 days. Furthermore, upregulation of 10 genes, Zbp1, Mx2, Irf7, Lgals9, Ifi47, Tapbp, Timp1, Trafd1, Psmb9, and Tap2, was seen upon virosomal-adjuvanted vaccine treatment, indicating that these biomarkers could be useful for the safety control of virosomal-adjuvanted vaccines. In summary, profiling biomarker gene expression could be a useful, rapid, and highly sensitive method of animal safety testing compared with conventional methods, and could be used to evaluate the safety of various types of influenza vaccines, including adjuvanted vaccine.

Elimination of the cold-chain dependence of a nanoemulsion adjuvanted vaccine against tuberculosis by lyophilization

Next-generation rationally-designed vaccine adjuvants represent a significant breakthrough to enable development of vaccines against challenging diseases including tuberculosis, HIV, and malaria. New vaccine candidates often require maintenance of a cold-chain process to ensure long-term stability and separate vials to enable bedside mixing of antigen and adjuvant. This presents a significant financial and technological barrier to worldwide implementation of such vaccines. Herein we describe the development and characterization of a tuberculosis vaccine comprised of both antigen and adjuvant components that are stable in a single vial at sustained elevated temperatures. Further this vaccine retains the ability to elicit both antibody and TH1 responses against the vaccine antigen and protect against experimental challenge with Mycobacterium tuberculosis. These results represent a significant breakthrough in the development of vaccine candidates that can be implemented throughout the world without being hampered by the necessity of a continuous cold chain or separate adjuvant and antigen vials.

Development of a multiplex gene expression assay for components of the endocrine growth axis in coho salmon

This study explores the efficacy of the Quantigene plex (QGP) technology for measuring a panel of endocrine growth-related transcripts in coho salmon, Oncorhynchus kisutch. The QGP technology permits the simultaneous quantification of multiple targeted mRNAs within a single tissue homogenate using sequence-specific probes and requires no reverse transcription (RT) or amplification as is required for RT-quantitative PCR (RT-qPCR). Using liver homogenates from coho salmon under fed and fasted conditions, we compared the detectable fold differences of steady-state mRNA levels between the QGP and probe-based RT-qPCR assays for insulin-like growth factors (igf1 and igf2), insulin-like growth factor binding proteins (igfbp1b, igfbp2a, and igfbp2b), somatolactin receptor (slr), and growth hormone receptors (ghr1 and ghr2). Significant, positive correlations for all genes between the two assays were found. In addition, the relatively low variance of results from the QGP assay suggests that this is a suitable method for a comprehensive analysis of endocrine growth-related transcripts and could potentially be used to develop assays for other gene networks in teleosts.

Functional and molecular responses in Mytilus edulis hemocytes exposed to bacteria, Vibrio splendidus

This study aims at examining the morphological, functional and molecular responses of Mytilus edulis hemocytes exposed to different strains of Gram-negative bacteria Vibrio splendidus (a virulent strain V. splendidus LGP32, V. splendidus LGP32 Δvsm without metalloprotease and an environmental type strain V. splendidus 7SHRW) at a 1:3 ratio for 2, 4, and 6 h. Our data showed that hemocytes could have a discriminative capacity towards microorganisms. Both V. splendidus LGP32 strains had an effect on hemocyte adhesion, phagocytosis abilities and oxidative burst, whereas the environmental strain 7SHRW induced weak and delayed hemocyte responses. At a molecular level, differential levels of candidate transcripts were measured in M. edulis hemocytes exposed to V. splendidus LGP32-GFP and 7SHRW. Mainly, a down-regulation of defensin was recorded in hemocytes exposed to V. splendidus LGP32. A significant up-regulation of lysozyme and proteasome 26S was observed at 2 h followed by a down-regulation at 4 and 6 h of exposure to the LGP32 strain. Similarly, SOD and GPx genes were up-regulated 2 h post-exposure to LGP32 strain and their expressions decreased after 4 and 6 h post-exposure. Further analysis is however needed in a near future to relate the transcript level variations with the physiological process.

Multiplexed detection of mRNA using porosity-tuned hydrogel microparticles

Transcriptional profiling, which is directly or indirectly associated with expressed protein levels, has been used in various applications including clinical prognosis and pharmaceutical investigation of drug activities. Although the widely used reverse transcription polymerase chain reaction (RT-PCR) allows for the quantification of absolute amounts of mRNA (mRNA) from inputs as small as a single cell, it is an indirect detection method that requires the amplification of cDNA copies of target mRNAs. Here, we report the quantification of unmodified full-length transcripts, using poly(ethylene) glycol diacrylate (PEGDA) hydrogel microparticles synthesized via stop flow lithography (SFL). We show that PEG600 serves as an effective porogen to allow for the capture of large (∼1000-3700 nt long) mRNAs. Our relatively simple hydrogel-based mRNA detection scheme uses a multibiotinylated universal label probe and provides assay performance (limit of detection of ∼6 amol of an in-vitro-transcribed model target) comparable to an existing commercial bead-based technology that uses branched DNA (bDNA) signal amplification. We also demonstrate a 3-plex mRNA detection, without cross-reactivity, using shape-encoded "intraplex" hydrogel microparticles. Our ability to tune the porosity of encoded hydrogel microparticles expands the utility of this platform to now quantify biomacromolecules ranging in size from large mRNAs to small miRNAs.

Expression of RAS-like family members, c-jun and c-myc mRNA levels in neoplastic hemocytes of soft-shell clams Mya arenaria using microsphere-based 8-plex branched DNA assay

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.

The importance of adjuvant formulation in the development of a tuberculosis vaccine

An effective protein-based vaccine for tuberculosis will require a safe and effective adjuvant. There are few adjuvants in approved human vaccines, including alum and the oil-in-water-based emulsions MF59 (Novartis Vaccines and Diagnostics), AS03 and AS04 (GlaxoSmithKline Biologics), AF03 (Sanofi), and liposomes (Crucell). When used with pure, defined proteins, both alum and emulsion adjuvants are effective at inducing primarily humoral responses. One of the newest adjuvants in approved products is AS04, which combines monophosphoryl lipid A, a TLR-4 agonist, with alum. In this study, we compared two adjuvants: a stable oil-in-water emulsion (SE) and a stable oil-in-water emulsion incorporating glucopyranosyl lipid adjuvant, a synthetic TLR-4 agonist (GLA-SE), each together with a recombinant protein, ID93. Both the emulsion SE and GLA-SE adjuvants induce potent cellular responses in combination with ID93 in mice. ID93/SE induced Th2-biased immune responses, whereas ID93/GLA-SE induced multifunctional CD4(+) Th1 cell responses (IFN-γ, TNF-α, and IL-2). The ID93/GLA-SE vaccine candidate induced significant protection in mice and guinea pigs, whereas no protection was observed with ID93/SE, as assessed by reductions in bacterial burden, survival, and pathology. These results highlight the importance of properly formulating subunit vaccines with effective adjuvants for use against tuberculosis.