TLR2 reprograms glucose metabolism in CD4+ T cells of rheumatoid arthritis patients to mediate cell hyperactivation and TNF-α secretion

OBJECTIVE

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease in which activated CD4+ T cells participate in the disease process by inducing inflammation. We aimed to investigate the role of Toll-like receptor 2 (TLR2) on CD4+ T cells in RA patients, and to elucidate the underlying mechanisms by which TLR2 contributes to the pathogenesis of RA.

METHODS

Serum samples were collected from RA patients and healthy controls. Soluble TLR2 levels were quantified using an enzyme-linked immunosorbent assay (ELISA). Flow cytometry was employed to assess the TLR2 expression level, activation status, cytokine production, reactive oxygen species (ROS) levels, and glucose uptake capacity of CD4+ T cells. Quantitative polymerase chain reaction (qPCR) was used to measure the expression of enzymes associated with glucose and lipid metabolism. The concentration of lactic acid in the culture supernatant was determined using a dedicated detection kit.

RESULTS

RA patients had higher levels of TLR2 in their serum, which positively correlated with C-reactive protein and rheumatoid factor. The expression level of TLR2 in CD4+ T cells of RA patients was increased, and TLR2+ cells showed higher activation levels than TLR2- cells. Activation of TLR2 in CD4+ T cells of RA patients promoted their activation, TNF-α secretion, and increased production of ROS. Furthermore, TLR2 activation led to changes in enzymes related to glucose metabolism, causing a shift in glucose metabolism towards the pentose phosphate pathway. Blocking oxidative phosphorylation and the pentose phosphate pathway had varying effects on CD4+ T cell function.

CONCLUSION

TLR2 reprograms the glucose metabolism of CD4+ T cells in RA patients, contributing to the development of RA through ROS-mediated cell hyperactivation and TNF-α secretion. Key Points • TLR2 is upregulated in CD4+ T cells of RA patients and correlates with disease severity markers such as CRP and RF. • Activation of TLR2 in CD4+ T cells promotes cell activation, TNF-α secretion, and increased ROS production, contributing to the pathogenesis of RA. • TLR2 activates glucose metabolism in CD4+ T cells, shifting towards the pentose phosphate pathway, which may be a novel therapeutic target for RA treatment. • Blocking glucose metabolism and ROS production can reduce CD4 + T cell hyperactivation and TNF-α secretion, indicating potential therapeutic strategies for RA management.

Controllably Self-Assembled Antibacterial Nanofibrils Based on Insect Cuticle Protein for Infectious Wound Healing

Developing self-assembled biomedical materials based on insect proteins is highly desirable due to their advantages of green, rich, and sustainable characters as well as excellent biocompatibility, which has been rarely explored. Herein, salt-induced controllable self-assembly, antibacterial performance, and infectious wound healing performance of an insect cuticle protein (OfCPH-2) originating from the Ostrinia furnacalis larva head capsule are investigated. Interestingly, the addition of salts could trigger the formation of beaded nanofibrils with uniform diameter, whose length highly depends on the salt concentration. Surprisingly, the OfCPH-2 nanofibrils not only could form functional films with broad-spectrum antibacterial abilities but also could promote infectious wound healing. More importantly, a possible wound healing mechanism was proposed, and it is the strong abilities of OfCPH-2 nanofibrils in promoting vascular formation and antibacterial activity that facilitate the process of infectious wound healing. Our exciting findings put forward instructive thoughts for developing innovative bioinspired materials based on insect proteins for wound healing and related biomedical fields.

Application of toll-like receptors (TLRs) and their agonists in cancer vaccines and immunotherapy

Toll-like receptors (TLRs) are pattern recognition receptors (PRRs) expressed in various immune cell types and perform multiple purposes and duties involved in the induction of innate and adaptive immunity. Their capability to propagate immunity makes them attractive targets for the expansion of numerous immunotherapeutic approaches targeting cancer. These immunotherapeutic strategies include using TLR ligands/agonists as monotherapy or combined therapeutic strategies. Several TLR agonists have demonstrated significant efficacy in advanced clinical trials. In recent years, multiple reports established the applicability of TLR agonists as adjuvants to chemotherapeutic drugs, radiation, and immunotherapies, including cancer vaccines. Cancer vaccines are a relatively novel approach in the field of cancer immunotherapy and are currently under extensive evaluation for treating different cancers. In the present review, we tried to deliver an inclusive discussion of the significant TLR agonists and discussed their application and challenges to their incorporation into cancer immunotherapy approaches, particularly highlighting the usage of TLR agonists as functional adjuvants to cancer vaccines. Finally, we present the translational potential of rWTC-MBTA vaccination [irradiated whole tumor cells (rWTC) pulsed with phagocytic agonists Mannan-BAM, TLR ligands, and anti-CD40 agonisticAntibody], an autologous cancer vaccine leveraging membrane-bound Mannan-BAM, and the immune-inducing prowess of TLR agonists as a probable immunotherapy in multiple cancer types.

Yeast derivatives as a source of bioactive components in animal nutrition: A brief review

With a long history of inclusion within livestock feeding programs, yeast and their respective derivatives are well-understood from a nutritional perspective. Originally used as sources of highly digestible protein in young animal rations in order to offset the use of conventional protein sources such as soybean and fish meal, application strategies have expanded in recent years into non-nutritional uses for all animal categories. For the case of yeast derivatives, product streams coming from the downstream processing of nutritional yeast, the expansion in use cases across species groups has been driven by a greater understanding of the composition of each derivative along with deeper knowledge of mechanistic action of key functional components. From improving feed efficiency, to serving as alternatives to antibiotic growth promoters and supporting intestinal health and immunity while mitigating pathogen shedding, new use cases are driven by a recognition that yeast derivatives contain specific bioactive compounds that possess functional properties. This review will attempt to highlight key bioactive categories within industrially applicable yeast derivatives and provide context regarding identification and characterization and mechanisms of action related to efficacy within a range of experimental models.

Transcriptomic profiling of clobetasol propionate-induced immunosuppression in challenged zebrafish embryos

In the ecotoxicological hazard assessment of chemicals, the detection of immunotoxicity is currently neglected. This is mainly due to the complexity of the immune system and the consequent lack of standardized procedures and markers for the comprehensive assessment of immunotoxic modes of action. In this study, we present a new approach applying transcriptome profiling to an immune challenge with a mixture of pathogen-associated molecular patterns (PAMPs) in zebrafish embryos, analyzing differential gene expression during acute infection with and without prior exposure to the immunosuppressive drug clobetasol propionate (CP). While PAMP injection itself triggered biological processes associated with immune activation, some of these genes were more differentially expressed upon prior exposure to CP than by immune induction alone, whereas others showed weaker or no differential regulation in response to the PAMP stimulus. All of these genes responding differently to PAMP after prior CP exposure showed additivity of PAMP- and CP-induced effects, indicating independent regulatory mechanisms. The transcriptomic profiles suggest that CP impaired innate immune induction by attenuating the response of genes involved in antigen processing, TLR signaling, NF-КB signaling, and complement activation. We propose this approach as a powerful method for detecting gene biomarkers for immunosuppressive modes of action, as it was able to identify alternatively regulated processes and pathways in a sublethal, acute infection zebrafish embryo model. This allowed to define biomarker candidates for immune-mediated effects and to comprehensively characterize immunosuppression. Ultimately, this work contributes to the development of molecular biomarker-based environmental hazard assessment of chemicals in the future.

Thrombocytopenia in COVID‑19 and vaccine‑induced thrombotic thrombocytopenia

The highly heterogeneous symptomatology and unpredictable progress of COVID-19 triggered unprecedented intensive biomedical research and a number of clinical research projects. Although the pathophysiology of the disease is being progressively clarified, its complexity remains vast. Moreover, some extremely infrequent cases of thrombotic thrombocytopenia following vaccination against SARS-CoV-2 infection have been observed. The present study aimed to map the signaling pathways of thrombocytopenia implicated in COVID-19, as well as in vaccine-induced thrombotic thrombocytopenia (VITT). The biomedical literature database, MEDLINE/PubMed, was thoroughly searched using artificial intelligence techniques for the semantic relations among the top 50 similar words (>0.9) implicated in COVID-19-mediated human infection or VITT. Additionally, STRING, a database of primary and predicted associations among genes and proteins (collected from diverse resources, such as documented pathway knowledge, high-throughput experimental studies, cross-species extrapolated information, automated text mining results, computationally predicted interactions, etc.), was employed, with the confidence threshold set at 0.7. In addition, two interactomes were constructed: i) A network including 119 and 56 nodes relevant to COVID-19 and thrombocytopenia, respectively; and ii) a second network containing 60 nodes relevant to VITT. Although thrombocytopenia is a dominant morbidity in both entities, three nodes were observed that corresponded to genes (AURKA, CD46 and CD19) expressed only in VITT, whilst ADAM10, CDC20, SHC1 and STXBP2 are silenced in VITT, but are commonly expressed in both COVID-19 and thrombocytopenia. The calculated average node degree was immense (11.9 in COVID-19 and 6.43 in VITT), illustrating the complexity of COVID-19 and VITT pathologies and confirming the importance of cytokines, as well as of pathways activated following hypoxic events. In addition, PYCARD, NLP3 and P2RX7 are key potential therapeutic targets for all three morbid entities, meriting further research. This interactome was based on wild-type genes, revealing the predisposition of the body to hypoxia-induced thrombosis, leading to the acute COVID-19 phenotype, the 'long-COVID syndrome', and/or VITT. Thus, common nodes appear to be key players in illness prevention, progression and treatment.

Recent progress in synthetic self-adjuvanting vaccine development

Vaccination is a proven way to protect individuals against many infectious diseases, as currently highlighted in the global COVID-19 pandemic. Peptides- or small molecule antigen-based vaccination offer advantages over the...

Microbiota modulate Doxorubicin induced cardiotoxicity

Chemotherapy has several adverse effects to patients, some of which are life-threatening. We hypothesized that Doxorubicin induced microbiome imbalance and intestinal damage may contribute to Doxorubicin induced cardiac dysfunction. Male adult (2-3 months) C57BL/6 mice were administered 3 mg/kg, 5 mg/kg, 7.5 mg/kg,15 mg/kg, 20 mg/kg doses of Doxorubicin. Echocardiography was performed at 7 and 14 days after Doxorubicin administration. 16S rRNA amplicon sequencing was used to characterize microbiome changes. Fecal microbiota transplantation (FMT) was performed to evaluate the role of the microbiota on Doxorubicin induced cardiac dysfunction. Doxorubicin dose dependently increases mortality rate and induces cardiac dysfunction. 5 mg/kg-Doxorubicin significantly induces decreased left ventricular ejection fraction (LVEF) and fraction shortening (FS) as well as increased cardiac fibrosis, inflammation and oxidative stress respond without increasing mortality. 5 mg/kg-Doxorubicin induces significant decreased colorectum length, increased loss of goblet cells, numbers of ulcers and infiltration of lymphocyte clusters and decreased tight junction protein ZO-1, as well as increased plasma endotoxin level measured by ELISA assay. 16S rRNA microbiota analysis shows that Doxorubicin-induced microbiota dysbiosis with decreased community richness compared with normal control mice. FMT to Doxorubicin-5 mg treated mice significantly improved cardiac function by increasing LVEF and FS as well as decreased perivascular and interstitial fibrosis; increased colorectum length, decreased the loss of goblet cells,infiltration of lymphocyte clusters,the number of ulcers and plasma endotoxin level; improved microbiota composition, function and diversity with increased abundance of Alloprevotella, Prevotellaceae_UCG-001 and Rikenellaceae_RC9_gut_group. We find that normal fecal transplantation improves cardiac function, decreases gut damage and alter microbiota composition induced by Doxorubicin. The microbiota appears to contribute to heart-gut interaction.

Subtractive Proteomics and Immuno-informatics Approaches for Multi-peptide Vaccine Prediction Against Klebsiella oxytoca and Validation Through In Silico Expression

Klebsiella oxytoca is a gram-negative bacterium. It is opportunistic in nature and causes hospital acquired infections. Subtractive proteomics and reverse vaccinology approaches were employed to screen out the best proteins for vaccine designing. Whole proteome of K. oxytoca strain ATCC 8724, consisting of 5483 proteins, was used for designing the vaccine. Total 1670 cytotoxic T lymphocyte (CTL) epitope were predicted through NetCTL while 1270 helper T lymphocyte (HTL) epitopes were predicted through IEDB server. The epitopes were screened for non-toxicity, allergenicity, antigenicity and water solubility. After epitope screening 300 CTL and 250 HTL epitopes were submitted to IFN-γ epitope server to predict their Interferon-γ induction response. The selected IFN-γ positive epitopes were tested for their binding affinity with MHCI-DRB1 by MHCPred. The 15 CTL and 13 HTL epitopes were joined by linkers AAY and GPGPG respectively in vaccine construct. Chain C of Pam3CSK4 (PDB ID; 2Z7X) was linked to the vaccine construct as an adjuvant. A 450aa long vaccine construct was submitted to I-TASSER server for 3D structure prediction. Thirteen Linear B cells were predicted by ABCPred server and 10 sets of discontinues epitopes for 3D vaccine structure were predicted by DiscoTope server. The modeled 3D vaccine construct was docked with human Toll-like receptor 2 (PDB ID: 6NIG) by PatchDock. The docked complexes were refined by FireDock. The selected docked complex showed five hydrogen bonds and one salt bridge. The vaccine sequence was reverse transcribed to get nucleotide sequence for In silico cloning. The reverse transcribed sequence strand was cloned in pET28a(+) expression vector. A clone containing 6586 bp was constructed including the 450 bp of query gene sequence.

Early pregnancy affects expression of Toll-like receptor signaling members in ovine spleen

Toll-like receptors (TLRs) are involved to the maternal immune tolerance. The spleen is essential for adaptive immune reactions. However, it is unclear that early pregnancy regulates TLR-mediated signalings in the maternal spleen. The purpose of this study was to investigate the effects of early pregnancy on expression of TLR signaling members in the ovine spleen. Ovine spleens were collected at day 16 of the estrous cycle, and at days 13, 16 and 25 of pregnancy (n = 6 for each group). Real-time quantitative PCR, western blot and immunohistochemistry analysis were used to detect TLR signaling members, including TLR2, TLR3, TLR4, TLR5, TLR7, TLR9, myeloid differentiation primary-response protein 88 (MyD88), tumor necrosis factor receptor associated factor 6 (TRAF6) and interleukin-1-receptor-associated kinase 1 (IRAK1). The results showed that expression levels of TLR2, TLR4 and IRAK1 were downregulated, but expression levels of TLR3, TLR5, TLR7, TLR9, TRAF6 and MyD88 were increased during early pregnancy. In addition, MyD88 protein was located in the capsule, trabeculae and splenic cords of the maternal spleen. This paper reports for the first time that early pregnancy has effects on TLR signaling pathways in the ovine spleen, which is beneficial for understanding the maternal immune tolerance during early pregnancy.

Simultaneous Onset of Mycobacterium kansasii Pulmonary Infection and Systemic Lupus Erythematosus: A Case Report

Patient: Female, 19-year-old

Final Diagnosis: Systemic lupus erythematosus

Symptoms: Cough • Fever • malaise and fatigue • polyarthralgia • skin rash

Medication: —

Clinical Procedure: —

Specialty: Rheumatology

Lung Transplantation Has a Strong Impact on the Distribution and Phenotype of Monocyte Subsets

BACKGROUND

Lung transplantation (LTx) is a last treatment option for patients with an end-stage pulmonary disease. Chronic lung allograft dysfunction, which generally manifests as bronchiolitis obliterans syndrome (BOS), is a major long-term survival limitation. During injury, inflammation and BOS monocytes are recruited. We determined whether changes in count, subset distribution, and functionality by surface marker expression coincided with BOS development.

METHODS

Fresh whole-blood samples were analyzed from 44 LTx patients, including 17 patients diagnosed with BOS, and compared with 10 age-matched healthy controls and 9 sarcoidosis patients as positive controls. Monocytes were quantified and analyzed using flow cytometry. Based on surface marker expression, classical, intermediate, and nonclassical subsets were determined, and functional phenotypes were investigated.

RESULTS

The absolute count of monocytes was decreased in LTx and slightly increased in BOS patients. The relative count shifted toward classical monocytes at the expense of nonclassical monocytes in LTx and BOS. Surface marker expression was highest on intermediate monocytes. The expression of both CD36 and CD163 was significantly increased in the LTx and BOS cohort. The difference between the BOS cohort and the LTx cohort was only subtle, with a significant decrease in HLA-DR expression on nonclassical monocytes in BOS.

CONCLUSIONS

Monocyte subsets and surface marker expression changed significantly in transplantation patients, while BOS-specific changes were understated. More research is needed to determine whether and how monocytes influence the disease process and how current immunosuppressants affect their normal function in vivo.

Endogenous Toll-like Receptor 2 Modulates Th1/Treg-Promoting Dendritic Cells in Mice Corneal Transplantation Model

PURPOSE

Endogenous toll-like receptor (TLR) 2 is linked to allograft rejection in corneal transplantation. TLR2 also could modulate dendritic cell (DC) phenotype, resulting in T cell polarization. Thus, we investigated the role of endogenous TLR2 on DC development and T cell polarization during corneal rejection.

MATERIALS AND METHODS

Corneas of BALB/c mice were transplanted into the eyes of C57BL/6 wild-type (WT) recipients and TLR2^-/- (KO) recipients. Graft survival and TLR2 mRNA expression were assessed. At day 14 after transplantation, to study endogenous TLR2 effects on DC development and function, surface expression of MHC classⅡ (MHCⅡ), CD86, CD80 and CD40 in ipsilateral cervical draining lymph nodes (DLNs) is measured by flow cytometry, and DC phenotype in corneas is detected by immunofluorescence. The levels of IL-12, IL-10 and IL-4 in corneas were measured by real time-qPCR (RT-qPCR). The ability of DCs to stimulate T cell polarization was assessed by IFN-γ expressions via RT-qPCR and immunohistochemistry.

RESULTS

TLR2 mRNA expression in corneas was peaked at day 14 post-transplantation in WT group. KO group improved corneal allograft survival compared to the WT group. In addition, the KO group decreased expression of CD86, CD80 and CD40 on DCs compared to the WT group. There was no difference in MHCⅡ expression in two groups. The CD11c⁺MHCⅡ⁺CD40^high DCs could not be detected in corneas of the KO group. Moreover, the KO group decreased IL-12 (Th1-promoting cytokines) mRNA expression and increasing IL-10 (Treg-promoting cytokines) mRNA expression compared to the WT group. IL-4 (Th2-promoting cytokines) mRNA expression gained no difference between the two groups. The IFN-γ (Th1 cytokines) expression was significantly decreased in the KO group compared to the WT group.

CONCLUSIONS

Endogenous TLR2 may contribute to allogeneic corneal rejection via Th1 immunity by activating Th1-promoting DCs and suppressing Treg-promoting DCs.

Rainbow Trout IgM+ B Cells Preferentially Respond to Thymus-Independent Antigens but Are Activated by CD40L

In the absence of class switch recombination and germinal centers, the mechanisms through which B cells from teleost fish mount extrafollicular immunoglobulin M (IgM) memory responses remains mostly unexplored. In this report, we demonstrate that teleost IgM⁺ B cells respond to CD40L, a thymus-dependent activation signal, similarly to mammalian B2 cells. However, when stimulated with different types of antigens, fish IgM⁺ B cells only reach a general activation state in response to antigens cataloged as thymus-independent 1 (TI-1) in mammals, as established through both functional assays and RNA sequencing. Interestingly, fish IgM⁺ B cells remained completely unresponsive to TI-2 antigens, suggesting that the engagement of innate receptors provided by TI-1 antigens is required for the activation of teleost B cells. Finally, a synergy between CD40L and TI-1 antigens was also demonstrated, further supporting that there is no clear dichotomy between thymus-dependent and TI responses in teleost fish.

Proteomics and Metabolomics for AKI Diagnosis

Acute kidney injury (AKI) is a severe and frequent condition in hospitalized patients. Currently, no efficient therapy of AKI is available. Therefore, efforts focus on early prevention and potentially early initiation of renal replacement therapy to improve the outcome in AKI. The detection of AKI in hospitalized patients implies the need for early, accurate, robust, and easily accessible biomarkers of AKI evolution and outcome prediction because only a narrow window exists to implement the earlier-described measures. Even more challenging is the multifactorial origin of AKI and the fact that the changes of molecular expression induced by AKI are difficult to distinguish from those of the diseases associated or causing AKI as shock or sepsis. During the past decade, a considerable number of protein biomarkers for AKI have been described and we expect from recent advances in the field of omics technologies that this number will increase further in the future and be extended to other sorts of biomolecules, such as RNAs, lipids, and metabolites. However, most of these biomarkers are poorly defined by their AKI-associated molecular context. In this review, we describe the state-of-the-art tissue and biofluid proteomic and metabolomic technologies and new bioinformatics approaches for proteomic and metabolomic pathway and molecular interaction analysis. In the second part of the review, we focus on AKI-associated proteomic and metabolomic biomarkers and briefly outline their pathophysiological context in AKI.

Pyroptosis of MCF7 Cells Induced by the Secreted Factors of hUCMSCs

Human umbilical cord mesenchymal stem cells (hUCMSCs) are superior to other sources of mesenchymal stem/stromal cells (MSCs), and they are used as a novel tool for cell-based cancer therapy. However, the mechanism underlying hUCMSC-induced cancer cell death is not clear. In the present study, we aimed to evaluate the effect of secreted factors of hUCMSCs on the breast cancer cell line MCF7 by exposing them to the conditioned medium (CM) of hUCMSCs. We evaluated the morphological changes, cell viability, cell cycle, apoptosis, DNA fragmentation, and interleukin-1β (IL-1β) secretion of CM-exposed MCF7 cells. The results showed that the secreted factors of hUCMSCs could cause MCF7 cell death by inducing pyroptosis. We also sequenced the total RNA, and the differentially expressed genes (DEGs) were subjected to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. A total of 2597 (1822 upregulated and 775 downregulated) genes were identified and 14 pathways were significantly enriched. The results showed that the expression of the pyroptosis-related genes NLRP1 and CASP4 and the inflammation-related pathways changed significantly in MCF7 cells exposed to the CM. To the best of our knowledge, this study is the first to report that the secreted factors of hUCMSCs can cause MCF7 cell pyroptosis. Furthermore, it is the first to examine the global gene expression in MCF7 cells exposed to CM. These results will provide valuable information for further studies on the mechanism of MCF7 cell pyroptosis induced by the secreted factors of hUCMSCs. It will also help understand the effect of hUCMSCs on cell-based breast cancer therapy.

Botulinum Toxin Type A-A Modulator of Spinal Neuron-Glia Interactions under Neuropathic Pain Conditions

Neuropathic pain represents a significant clinical problem because it is a chronic condition often refractory to available therapy. Therefore, there is still a strong need for new analgesics. Botulinum neurotoxin A (BoNT/A) is used to treat a variety of clinical diseases associated with pain. Glia are in continuous bi-directional communication with neurons to direct the formation and refinement of synaptic connectivity. This review addresses the effects of BoNT/A on the relationship between glia and neurons under neuropathic pain. The inhibitory action of BoNT/A on synaptic vesicle fusion that blocks the release of miscellaneous pain-related neurotransmitters is known. However, increasing evidence suggests that the analgesic effect of BoNT/A is mediated through neurons and glial cells, especially microglia. In vitro studies provide evidence that BoNT/A exerts its anti-inflammatory effect by diminishing NF-κB, p38 and ERK1/2 phosphorylation in microglia and directly interacts with Toll-like receptor 2 (TLR2). Furthermore, BoNT/A appears to have no more than a slight effect on astroglia. The full activation of TLR2 in astroglia appears to require the presence of functional TLR4 in microglia, emphasizing the significant interaction between those cell types. In this review, we discuss whether and how BoNT/A affects the spinal neuron–glia interaction and reduces the development of neuropathy.

Histopathological Injuries, Ultrastructural Changes, and Depressed TLR Expression in the Small Intestine of Broiler Chickens with Aflatoxin B₁

To explore AFB₁-induced damage of the small intestine, the changes in structure and expression of TLRs (Toll-like Receptors) in the small intestine of chickens were systematically investigated. Ninety healthy neonatal Cobb chickens were randomized into a control group (0 mg/kg AFB₁) and an AFB₁ group (0.6 mg/kg AFB₁). The crypt depth of the small intestine in the AFB₁ group was significantly increased in comparison to the control chickens, while the villus height and area were evidently decreased, as well as the villus:crypt ratio and epithelial thickness. The histopathological observations showed that the villi of the small intestine exposed to AFB₁ were obviously shedding. Based on ultrastructural observation, the absorptive cells of small intestine in the AFB₁ group exhibited fewer microvilli, mitochondrial vacuolation and the disappearance of mitochondrial cristae, and junctional complexes as well as terminal web. Moreover, the number of goblet cells in the small intestine in the AFB₁ group significantly decreased. Also, AFB₁ evidently decreased the mRNA expression of TLR2-2, TLR4, and TLR7 in the small intestine. Taken together, our study indicated that dietary 0.6 mg/kg AFB₁ could induce histopathological injuries and ultrastructural changes, and depress levels of TLR mRNA in the chicken small intestine.

The Soluble Form of Toll-Like Receptor 2 Is Elevated in Serum of Multiple Sclerosis Patients: A Novel Potential Disease Biomarker

Multiple sclerosis (MS) is an immune-mediated inflammatory demyelinating disease of the central nervous system. It was previously shown that toll-like receptor (TLR)-2 signaling plays a key role in the murine experimental autoimmune encephalomyelitis (EAE) model of MS, and that TLR2-stimulation of regulatory T cells (Tregs) promotes their conversion to T helper 17 (Th17) cells. Here, we sought potential sources of TLR2 stimulation and evidence of TLR2 activity in MS patient clinical samples. Soluble TLR2 (sTLR2) was found to be significantly elevated in sera of MS patients (n = 21), in both relapse and remission, compared to healthy controls (HC) (n = 24). This was not associated with the acute phase reaction (APR) as measured by serum C-reactive protein (CRP) level, which was similarly increased in MS patients compared to controls. An independent validation cohort from a different ethnic background showed a similar upward trend in mean sTLR2 values in relapsing-remitting MS (RRMS) patients, and significant differences in sTLR2 values between patients and HC were preserved when the data from the two cohorts were pooled together (n = 41 RRMS and 44 HC, P = 0.0006). TLR2-stimulants, measured using a human embryonic kidney (HEK)-293 cells transfectant reporter assay, were significantly higher in urine of MS patients than HC. A screen of several common urinary tract infections (UTI)-related organisms showed strong induction of TLR2-signaling in the same assay. Taken together, these results indicate that two different markers of TLR2-activity—urinary TLR2-stimulants and serum sTLR2 levels—are significantly elevated in MS patients compared to HC.

Comparison of the Expression Changes after Botulinum Toxin Type A and Minocycline Administration in Lipopolysaccharide-Stimulated Rat Microglial and Astroglial Cultures

Botulinum neurotoxin type A (BoNT/A) and minocycline are potent drugs used in clinical therapies. The primary molecular mechanism of BoNT/A is the cleavage of SNARE proteins, which prevents cells from releasing neurotransmitters from vesicles, while the effects of minocycline are related to the inhibition of p38 activation. Both BoNT/A and minocycline exhibit analgesic effects, however, their direct impact on glial cells is not fully known. Therefore, the aim of the present study was to determine the effects of those drugs on microglial and astroglial activity after lipopolysaccharide (LPS) stimulation and their potential synergistic action. Our results show that BoNT/A and minocycline influenced primary microglial cells by inhibiting intracellular signaling pathways, such as p38, ERK1/2, NF-κB, and the release of pro-inflammatory factors, including IL-1β, IL-18, IL-6, and NOS2. We have revealed that, in contrast to minocycline, BoNT/A treatment did not decrease LPS-induced release of pro-inflammatory factors in the astroglia. In addition, BoNT/A decreased SNAP-23 in both types of glial cells and also SNAP-25 expressed only in astrocytes. Moreover, BoNT/A increased TLR2 and its adaptor protein MyD88, but not TLR4 exclusively in microglial cells. Furthermore, we have shown the impact of BoNT/A on microglial and astroglial cells, with a particular emphasis on its molecular target, TLR2. In contrast, minocycline did not affect any of those factors. We have revealed that despite of different molecular targets, minocycline, and BoNT/A reduced the release of microglia-derived pro-inflammatory factors. In conclusion, we have shown that BoNT/A and minocycline are effective drugs for the management of neuroinflammation by dampening the activation of microglial cells, with minocycline also affecting astroglial activity.

Effects of probiotics on Toll‑like receptor expression in ulcerative colitis rats induced by 2,4,6‑trinitro‑benzene sulfonic acid

The present study aimed to investigate the regulatory effect of probiotics on the expression of Toll‑like receptors (TLRs) in an ulcerative colitis (UC) rat model, and to determine the role of probiotics in the underlying mechanisms through which UC develops and progresses in rat models. Rats were randomly allocated to one of the four following groups: i) The healthy control, ii) the model, iii) the Golden bifid treatment group, and iv) the TLR4 monoclonal antibody (TLR4mAb) intervention group. The UC rat model was established using 2,4,6‑trinitro‑benzene sulfonic acid. The general status and histological changes of rats were scored using the disease activity index and the histopathological scoring method, respectively. In these rats, the expression of TLR4 and TLR2 was measured using reverse transcription‑quantitative polymerase chain reaction. The expression of TLR4 and TLR2 in the model group was significantly higher than that in the healthy control group. However, when compared with the model rats, those that received either Golden bifid treatment or TLR4mAb intervention exhibited significantly decreased mRNA expression levels of TLR4 and TLR2 (P<0.05). The development of UC is characterized by an abnormal immune response in the intestines. Probiotics alleviated inflammatory reactions in rats with UC. The underlying mechanism of UC may be associated with the expression of TLRs and the subsequent release of inflammatory cytokines.

Glycogen synthase kinase 3β in Toll-like receptor signaling

Toll-like receptors (TLRs) play a critical role in the innate immune response against pathogens. Each TLR recognizes specific pathogen-associated molecular patterns, after which they activate the adaptor protein MyD88 or TRIF-assembled signaling complex to produce immune mediators, including inflammatory cytokines and type I IFNs. Although the activation of TLR is important for host defense, its uncontrolled activation can damage the host. During the past decade, numerous studies have demonstrated that GSK3β is a key regulator of inflammatory cytokine production in MyD88-mediated TLR signaling via TLR2 and TLR4. Recently, GSK3β has also been implicated in the TRIF-dependent signaling pathway via TLR3. In this review, we describe current advances on the regulatory role of GSK3β in immune responses associated with various TLRs. A better understanding of the role of GSK3β in TLR signaling might lead to more effective anti-inflammatory interventions. [BMB Reports 2016; 49(6): 305-310]

Innate immune regulation of autoimmunity in multiple sclerosis: Focus on the role of Toll-like receptor 2

Innate immunity relies on a set of germline-encoded receptors including Toll-like receptors (TLRs) that enable the host to discriminate between self and non-self. Multiple sclerosis (MS) is an autoimmune inflammatory demyelinating disease of the central nervous system (CNS). Infections are thought to play an important role in disease susceptibility. The role of innate immunity in MS has been recently appreciated. TLR2, a member of the TLR family, forms heterodimers with either TLR1 or TLR6 and detects a wide range of microbial as well as self-derived molecular structures. It may thus be important both in fighting infection and in activating autoimmunity. In this review, we discuss innate regulation of autoimmunity in MS with a focus on the role of TLR2 signaling.

Genetic dissection of host immune response in pneumonia development and progression

The role of host genetic variation in pneumonia development and outcome is poorly understood. We studied common polymorphisms in the genes of proinflammatory cytokines (IL6 rs1800795, IL8 rs4073, IL1B rs16944), anti-inflammatory cytokines (IL10 rs1800896, IL4 rs2243250, IL13 rs20541) and toll-like receptors (TLR2 rs5743708 and rs4696480, TLR4 rs4986791, TLR9 rs352139, rs5743836 and rs187084) in patients with community-acquired pneumonia (CAP) (390 cases, 203 controls) and nosocomial pneumonia (355 cases, 216 controls). Experimental data were included in a series of 11 meta-analyses and eight subset analyses related to pneumonia susceptibility and outcome. TLR2 rs5743708 minor genotype appeared to be associated with CAP/Legionnaires’ disease/pneumococcal disease. In CAP patients, the IL6 rs1800795-C allele was associated with severe sepsis/septic shock/severe systemic inflammatory response, while the IL10 rs1800896-A allele protected against the development of these critical conditions. To contribute to deciphering of the above results, we performed an in silico analysis and a qualitative synthesis of literature data addressing basal and stimulated genotype-specific expression level. This data together with database information on transcription factors’ affinity changes caused by SNPs in putative promoter regions, the results of linkage disequilibrium analysis along with SNPs functional annotations supported assumptions about the complexity underlying the revealed associations.

Coxiella burnetii Infects Primary Bovine Macrophages and Limits Their Host Cell Response

Although domestic ruminants have long been recognized as the main source of human Q fever, little is known about the lifestyle that the obligate intracellular Gram-negative bacterium Coxiella burnetii adopts in its animal host. Because macrophages are considered natural target cells of the pathogen, we established primary bovine monocyte-derived macrophages (MDM) as an in vitro infection model to study reservoir host-pathogen interactions at the cellular level. In addition, bovine alveolar macrophages were included to take cell type peculiarities at a host entry site into account. Cell cultures were inoculated with the virulent strain Nine Mile I (NMI; phase I) or the avirulent strain Nine Mile II (NMII; phase II). Macrophages from both sources internalized NMI and NMII. MDM were particularly permissive for NMI internalization, but NMI and NMII replicated with similar kinetics in these cells. MDM responded to inoculation with a general upregulation of Th1-related cytokines such as interleukin-1β (IL-1β), IL-12, and tumor necrosis factor alpha (TNF-α) early on (3 h postinfection). However, inflammatory responses rapidly declined when C. burnetii replication started. C. burnetii infection inhibited translation and release of IL-1β and vastly failed to stimulate increased expression of activation markers, such as CD40, CD80, CD86, and major histocompatibility complex (MHC) molecules. Such capability of limiting proinflammatory responses may help Coxiella to protect itself from clearance by the host immune system. The findings provide the first detailed insight into C. burnetii-macrophage interactions in ruminants and may serve as a basis for assessing the virulence and the host adaptation of C. burnetii strains.

Toll-Like Receptor 2 Mediates In Vivo Pro- and Anti-inflammatory Effects of Mycobacterium Tuberculosis and Modulates Autoimmune Encephalomyelitis

Mycobacteria display pro- and anti-inflammatory effects in human and experimental pathology. We show here that both effects are mediated by Toll-like receptor 2 (Tlr2), by exploiting a previously characterized Tlr2 variant (Met82Ile). Tlr2 82ile promoted self-specific proinflammatory polarization as well as expansion of ag-specific FoxP3(+) Tregs, while Tlr2 82met impairs the expansion of Tregs and reduces the production of IFN-γ and IL-17 proinflammatory cytokines. Preferential dimerization with Tlr1 or Tlr6 could not explain these differences. In silico, we showed that Tlr2 variant Met82Ile modified the binding pocket for peptidoglycans and participated directly to a putative binding pocket for sugars and cadherins. The distinct pro- and anti-inflammatory actions impacted severity, extent of remission, and distribution of the lesions within the central nervous system of experimental autoimmune encephalomyelitis. Thus, Tlr2 has a janus function in vivo as mediator of the role of bacterial products in balancing pro- and anti-inflammatory immune responses.

Upregulation of inflammatory gene transcripts in periosteum of chronic migraineurs: Implications for extracranial origin of headache

OBJECTIVE

Chronic migraine (CM) is often associated with chronic tenderness of pericranial muscles. A distinct increase in muscle tenderness prior to onset of occipital headache that eventually progresses into a full-blown migraine attack is common. This experience raises the possibility that some CM attacks originate outside the cranium. The objective of this study was to determine whether there are extracranial pathophysiologies in these headaches.

METHODS

We biopsied and measured the expression of gene transcripts (mRNA) encoding proteins that play roles in immune and inflammatory responses in affected (ie, where the head hurts) calvarial periosteum of (1) patients whose CMs are associated with muscle tenderness and (2) patients with no history of headache.

RESULTS

Expression of proinflammatory genes (eg, CCL8, TLR2) in the calvarial periosteum significantly increased in CM patients attesting to muscle tenderness, whereas expression of genes that suppress inflammation and immune cell differentiation (eg, IL10RA, CSF1R) decreased.

INTERPRETATION

Because the upregulated genes were linked to activation of white blood cells, production of cytokines, and inhibition of NF-κB, and the downregulated genes were linked to prevention of macrophage activation and cell lysis, we suggest that the molecular environment surrounding periosteal pain fibers is inflamed and in turn activates trigeminovascular nociceptors that reach the affected periosteum through suture branches of intracranial meningeal nociceptors and/or somatic branches of the occipital nerve. This study provides the first set of evidence for localized extracranial pathophysiology in CM. Ann Neurol 2016;79:1000-1013.

PE_PGRS33 Contributes to Mycobacterium tuberculosis Entry in Macrophages through Interaction with TLR2

PE_PGRS represent a large family of proteins typical of pathogenic mycobacteria whose members are characterized by an N-terminal PE domain followed by a large Gly-Ala repeat-rich C-terminal domain. Despite the abundance of PE_PGRS-coding genes in the Mycobacterium tuberculosis (Mtb) genome their role and function in the biology and pathogenesis still remains elusive. In this study, we generated and characterized an Mtb H37Rv mutant (MtbΔ33) in which the structural gene of PE_PGRS33, a prototypical member of the protein family, was inactivated. We showed that this mutant entered macrophages with an efficiency up to ten times lower than parental or complemented strains, while its efficiency in infecting pneumocytes remained unaffected. Interestingly, the lack of PE_PGRS33 did not affect the intracellular growth of this mutant in macrophages. Using a series of functional deletion mutants of the PE_PGRS33 gene to complement the MtbΔ33 strain, we demonstrated that the PGRS domain is required to mediate cell entry into macrophages, with the key domain encompassing position 140–260 amino acids of PE_PGRS33. PE_PGRS33-mediated entry into macrophages was abolished in TLR2-deficient mice, as well as following treatment with wortmannin or an antibody against the complement receptor 3 (CR3), indicating that PE_PGRS33-mediated entry of Mtb in macrophages occurs through interaction with TLR2.

Polymorphisms in Toll-like receptor genes are associated with vitiligo

Background: The members of Toll-like receptor (TLR) family are responsible for recognizing various molecular patterns associated with pathogens. Their expression is not confined to immune cells and have been detected in skin cells such as keratinocytes and melanocytes. As part of a generated response to pathogens, TLRs are involved in inducing inflammatory mediators to combat these threats. It is therefore not surprising that TLRs have been implicated in inflammatory skin diseases, including atopic dermatitis and psoriasis. Likewise, as key players in autoimmunity, they have been associated with a number of autoimmune diseases. Based on this, the role of TLRs in vitiligo could be suspected, but is yet to be clearly established.

Methods: In order to conduct a genetic association analysis, 30 SNPs were selected from TLR1-TLR8 and TLR10 regions to be genotyped in Estonian case-control cohort consisting of 139 vitiligo patients and 307 healthy control individuals. The patients were further analyzed in subgroups based on sex, age of onset, occurrence of vitiligo among relatives, extent of depigmented areas, vitiligo progression activity, appearance of Köbner's phenomenon, existence of halo naevi, and incidence of spontaneous repigmentation.

Results: The most notable finding came with SNP rs179020 situated in TLR7 gene, that was associated in entire vitiligo (Padj = 0.0065) and also several subgroup analyses. Other single marker and haplotype analyses pointed to TLR3, TLR4, and TLR10 genes.

Conclusions: This study investigated the genetic regions of nine TLR genes in relation to vitiligo susceptibility. The main results were the associations of TLR7 SNPs with vitiligo, while several other associations were obtained from the remaining TLR gene regions. This suggests that in addition to other inflammatory skin diseases, TLRs affect the development of vitiligo, thus making them interesting targets for future research.

Cutting edge: New chimeric NOD2/TLR2 adjuvant drastically increases vaccine immunogenicity

TLR ligands are critical activators of innate immunity and are being developed as vaccine adjuvants. However, their usefulness in conjunction with NOD-like receptor agonists remains poorly studied. In this study, we evaluated a new ligand that targets both TLR2 and NOD2 receptors. We assessed its ability to enhance dendritic cell maturation in vitro in addition to improving systemic and mucosal immune responses in mice. The chimeric NOD2/TLR2 ligand induced synergistic upregulation of dendritic cell maturation markers, costimulatory molecules, and secretion of proinflammatory cytokines compared with combinations of separate ligands. Furthermore, when coadministered with biodegradable nanoparticles carrying a model Ag, the ligand was able to induce high Ag-specific IgA and IgG titers at both systemic and mucosal sites after parenteral immunizations. These findings point out the potential utility of chimeric molecules TLR/NOD as adjuvants for vaccines to induce systemic and mucosal immune responses.

Chemoproteomics reveals Toll-like receptor fatty acylation

Background

Palmitoylation is a 16-carbon lipid post-translational modification that increases protein hydrophobicity. This form of protein fatty acylation is emerging as a critical regulatory modification for multiple aspects of cellular interactions and signaling. Despite recent advances in the development of chemical tools for the rapid identification and visualization of palmitoylated proteins, the palmitoyl proteome has not been fully defined. Here we sought to identify and compare the palmitoylated proteins in murine fibroblasts and dendritic cells.

Results

A total of 563 putative palmitoylation substrates were identified, more than 200 of which have not been previously suggested to be palmitoylated in past proteomic studies. Here we validate the palmitoylation of several new proteins including Toll-like receptors (TLRs) 2, 5 and 10, CD80, CD86, and NEDD4. Palmitoylation of TLR2, which was uniquely identified in dendritic cells, was mapped to a transmembrane domain-proximal cysteine. Inhibition of TLR2 S-palmitoylation pharmacologically or by cysteine mutagenesis led to decreased cell surface expression and a decreased inflammatory response to microbial ligands.

Conclusions

This work identifies many fatty acylated proteins involved in fundamental cellular processes as well as cell type-specific functions, highlighting the value of examining the palmitoyl proteomes of multiple cell types. S-palmitoylation of TLR2 is a previously unknown immunoregulatory mechanism that represents an entirely novel avenue for modulation of TLR2 inflammatory activity.

Electronic supplementary material

The online version of this article (doi:10.1186/s12915-014-0091-3) contains supplementary material, which is available to authorized users.

[Regulation of expression, function, and inflammatory responses of innate immune receptor Toll-like receptor-2 (TLR2) during inflammatory responses against infection]

Toll-like receptor-2 (TLR2) is one of the important innate immune receptors that play an important role in recognizing the pathogens and producing inflammatory cytokines. In this review, we focus on the regulatory mechanisms of expression, function and inflammatory responses of TLR2 during pathogenic infection in innate immune cells. We first showed that nontypeable Haemophilus influenzae (NTHi), an important human pathogen that exacerbates otitis media and chronic obstructive pulmonary diseases (COPD), induces inflammatory responses through activation of NF-κB via two distinct signals, NIK-IKKα/β-IκBα and MKK3/6-p38 pathways. Moreover, TLR2 was greatly up-regulated by NTHi through the positive IKK-IκBα-dependent NF-κB pathway and the negative MKK3/6-p38α/β pathway. Importantly, glucocorticoids synergistically enhance NTHi-induced TLR2 up-regulation likely via a negative cross-talk with the inhibitory p38 MAPK. The results provide novel insights into the role of glucocorticoids in regulating host defense and innate immune responses through TLR2 regulation. We next focused on the pathogenesis of cystic fibrosis (CF), a common lethal inherited disorder characterized by recurrent pulmonary infections and obstruction caused by chronic mucus hypersecretion and inflammation. We demonstrated an increased expression of TLR2, due to an enhanced DNA de-methylation and Sp1-dependent transcriptional activation in CF epithelial cells. Furthermore, a Th17 cytokine IL-17A synergistically increased TLR2 signal through an enhancement of p38 phosphorylation. These studies suggest the importance of TLR2 and IL-17 signals in the pathogenesis of CF. Finally, by focusing on neutrophils and CF airway epithelial cells, we identified curcumin as a potent inhibitor of TLR2-mediated inflammatory responses.

Coexpression of TLR2 or TLR4 with HLA-DR potentiates the superantigenic activities of Mycoplasma arthritidis-derived mitogen

Mycoplasma arthritidis-derived mitogen (MAM) is a member of the superantigen family that structurally differs from other members while still capable of initiating cognate APC/T cell interaction. In addition to the critical role of MHC class II molecules, it has been suggested that TLR2 and TLR4 may cooperate with MHC class II during MAM-induced responses. In this study, we investigated the direct involvement of TLR2 and TLR4 in MAM binding and presentation to T cells. Our results showed that MAM fails to bind to TLR2- and TLR4-transfected cells. However, coexpression of TLR2 or TLR4 with HLA-DR significantly increases MAM binding and the subsequent T cell activation compared with cells expressing HLA-DR alone. The upregulated MAM binding and activity in HLA-DR/TLR-transfected cells is abrogated by an anti-HLA-DR Ab. Interestingly, we also found that MAM complexed with soluble HLA-DR is capable of binding to both TLR2 and TLR4. The enhancing effect of TLR2 or TLR4 on MAM-induced T cell proliferation was not due to TLR ligand contamination in the MAM preparation. Taken together, these results strongly suggest that binding of MAM to HLA-DR leads to a conformational change in MAM structure allowing its interaction with TLR2 and TLR4 and a better recognition by T cells.

Toll-like receptor 2 is required for autoantibody production and development of renal disease in pristane-induced lupus

OBJECTIVE

The mechanisms involved in breaking immunologic tolerance against nuclear autoantigens in systemic lupus erythematosus (SLE) are not fully understood. Our recent studies in nonautoimmune mice provided evidence of an important role of Toll-like receptor 2 (TLR-2) in antichromatin autoantibody induction by high mobility group box chromosomal protein 1-nucleosome complexes derived from apoptotic cells. The objective of this study was to investigate whether TLR-2 signaling is required for the induction of autoantibodies and the development of SLE-like disease in murine pristane-induced lupus.

METHODS

Lupus-like disease in C57BL/6 and TLR-2(-/-) mice was induced by pristane injection. The numbers of immune cells and serum cytokine concentrations were determined by flow cytometry. Renal disease was assessed by quantification of proteinuria, histologic analyses, and enzyme-linked immunospot assay.

RESULTS

Pristane-injected TLR-2(-/-) mice generated reduced numbers of splenic CD138+/cytoplasmic κL/λL chain-positive plasma cells and displayed diminished IgG responses against double-stranded DNA, histones, nucleosomes, some extractable nuclear autoantigens, and cardiolipin when compared with wild- type controls. TLR-2 deficiency prevented the pristane-induced systemic release of interleukin-6 (IL-6) and IL-10. The absence of TLR-2 attenuated peritoneal recruitment of CD11c+ cells and formation of lipogranulomas. Importantly, the renal disease that developed in pristane-treated TLR-2(-/-) mice was less severe than that in control mice, as reflected by milder proteinuria, reduced glomerular deposition of IgG and complement, and decreased renal infiltration of autoantibody-secreting cells.

CONCLUSION

TLR-2 is required for the production of prototypical lupus autoantibodies and the development of renal disease in pristane-induced murine lupus. Interference with TLR-2 signaling may be a promising novel strategy for the treatment of SLE.

Teleost T and NK cell immunity

The main function of the immune system is to maintain the organism's homeostasis when invaded by foreign material or organisms. Prior to successful elimination of the invader it is crucial to distinguish self from non-self. Most pathogens and altered cells can be recognized by immune cells through expressed pathogen- or danger-associated molecular patterns (PAMPS or DAMPS, respectively), through non-self (e.g. allogenic or xenogenic cells) or missing major histocompatibility (MHC) class I molecules (some virus-infected target cells), and by presenting foreign non-self peptides of intracellular (through MHC class I-e.g. virus-infected target cells) or extracellular (through MHC class II-e.g. from bacteria) origin. In order to eliminate invaders directly or by destroying their ability to replicate (e.g. virus-infected cells) specialized immune cells of the innate and adaptive responses appeared during evolution. The first line of defence is represented by the evolutionarily ancient macrophages and natural killer (NK) cells. These innate mechanisms are well developed in bony fish. Two types of NK cell homologues have been described in fish: non-specific cytotoxic cells and NK-like cells. Adaptive cell-mediated cytotoxicity (CMC) requires key molecules expressed on cytotoxic T lymphocytes (CTLs) and target cells. CTLs kill host cells harbouring intracellular pathogens by binding of their T cell receptor (TCR) and its co-receptor CD8 to a complex of MHC class I and bound peptide on the infected host cell. Alternatively, extracellular antigens are taken up by professional antigen presenting cells such as macrophages, dendritic cells and B cells to process those antigens and present the resulting peptides in association with MHC class II to CD4(+) T helper cells. During recent years, genes encoding MHC class I and II, TCR and its co-receptors CD8 and CD4 have been cloned in several fish species and antibodies have been developed to study protein expression in morphological and functional contexts. Functional assays for innate and adaptive lymphocyte responses have been developed in only a few fish species. This review summarizes and discusses recent results and developments in the field of T and NK cell responses with focus on economically important and experimental model fish species in the context of vaccination.

The role of IL-15 in gastrointestinal diseases: a bridge between innate and adaptive immune response

IL-15 is a member of the IL-2 family of cytokines whose signaling pathways are a bridge between innate and adaptive immune response. IL-15 is part of the intestinal mucosal barrier, and functions to modulate gut homeostasis. IL-15 has pivotal roles in the control of development, proliferation and survival of both innate and adaptive immune cells. IL-15 becomes up-regulated in the inflamed tissue of intestinal inflammatory disease, such as IBD, Celiac Disease and related complications. Indeed, several studies have reported that IL-15 may participate to the pathogenesis of these diseases. Furthermore, although IL-15 seems to be responsible for inflammation and autoimmunity, it also may increase the immune response against cancer. For these reasons, we decided to study the intestinal mucosa as an 'immunological niche', in which immune response, inflammation and local homeostasis are modulated. Understanding the role of the IL-15/IL-15R system will provide a scientific basis for the development of new approaches that use IL-15 for immunotherapy of autoimmune diseases and malignancies. Indeed, a better understanding of the complexity of the mucosal immune system will contribute to the general understanding of immuno-pathology, which could lead to new therapeutical tools for widespread immuno-mediated diseases.

TLR2 in pleural fluid is modulated by talc particles during pleurodesis

The aim of this study was to examine the role of TLR2 molecule in pleural space during thoracoscopic talc pleurodesis period in patients with malignant pleural effusion. We analyzed TLR2 molecule in soluble form as well as on membrane of granulocytes in pleural fluid. Pleural fluid examination was done at three intervals during pleurodesis procedure: 1st—before the thoracoscopic procedure, 2nd—2 hours after the terminating thoracoscopic procedure with talc insufflation, 3rd—24 hours after the thoracoscopic procedure. We reported significant increase of soluble TLR2 molecule in pleural fluid effusion during talc pleurodesis from preoperative value. This increase was approximately 8-fold in the interval of 24 hours. The changes on granulocyte population were quite different. The mean fluorescent intensity of membrane TLR2 molecule examined by flow cytometry on granulocyte population significantly decreased after talc exposure with comparison to prethoracoscopic density. To estimate the prognostic value of TLR2 expression in pleural fluid patients were retrospectively classified into either prognostically favourable or unfavourable groups. Our results proved that patients with favourable prognosis had more than 3-fold higher soluble TLR2 level in pleural fluid early, 2 hours after talc pleurodesis intervention.

Application of an integrative computational framework in trancriptomic data of atherosclerotic mice suggests numerous molecular players

Atherosclerosis is a multifactorial disease involving a lot of genes and proteins recruited throughout its manifestation. The present study aims to exploit bioinformatic tools in order to analyze microarray data of atherosclerotic aortic lesions of ApoE knockout mice, a model widely used in atherosclerosis research. In particular, a dynamic analysis was performed among young and aged animals, resulting in a list of 852 significantly altered genes. Pathway analysis indicated alterations in critical cellular processes related to cell communication and signal transduction, immune response, lipid transport, and metabolism. Cluster analysis partitioned the significantly differentiated genes in three major clusters of similar expression profile. Promoter analysis applied to functional related groups of the same cluster revealed shared putative cis-elements potentially contributing to a common regulatory mechanism. Finally, by reverse engineering the functional relevance of differentially expressed genes with specific cellular pathways, putative genes acting as hubs, were identified, linking functionally disparate cellular processes in the context of traditional molecular description.