Enhanced Virulence of Chlamydia muridarum Respiratory Infections in the Absence of TLR2 Activation

Chlamydia trachomatis is a common sexually transmitted pathogen and is associated with infant pneumonia. Data from the female mouse model of genital tract chlamydia infection suggests a requirement for TLR2-dependent signaling in the induction of inflammation and oviduct pathology. We hypothesized that the role of TLR2 in moderating mucosal inflammation is site specific. In order to investigate this, we infected mice via the intranasal route with C. muridarum and observed that in the absence of TLR2 activation, mice had more severe disease, higher lung cytokine levels, and an exaggerated influx of neutrophils and T-cells into the lungs. This could not be explained by impaired bacterial clearance as TLR2-deficient mice cleared the infection similar to controls. These data suggest that TLR2 has an anti-inflammatory function in the lung during Chlamydia infection, and that the role of TLR2 in mucosal inflammation varies at different mucosal surfaces

Development of a novel DDS for site-specific PEGylated proteins

Because of the shifted focus in life science research from genome analyses to genetic and protein function analyses, we now know functions of numerous proteins. These analyses, including those of newly identified proteins, are expected to contribute to the identification of proteins of therapeutic value in various diseases. Consequently, pharmacoproteomic-based drug discovery and development of protein therapies attracted a great deal of attention in recent years. Clinical applications of most of these proteins are, however, limited because of their unexpectedly low therapeutic effects, resulting from the proteolytic degradation in vivo followed by rapid removal from the circulatory system. Therefore, frequent administration of excessively high dose of a protein is required to observe its therapeutic effect in vivo. This often results in impaired homeostasis in vivo and leads to severe adverse effects. To overcome these problems, we have devised a method for chemical modification of proteins with polyethylene glycol (PEGylation) and other water-soluble polymers. In addition, we have established a method for creating functional mutant proteins (muteins) with desired properties, and developed a site-specific polymer-conjugation method to further improve their therapeutic potency. In this review, we are introducing our original protein-drug innovation system mentioned above

Transmission Electron Microscopy Reveals Distinct Macrophage- and Tick Cell-Specific Morphological Stages of Ehrlichia chaffeensis

Background: Ehrlichia chaffeensis is an emerging tick-borne rickettsial pathogen responsible for human monocytic ehrlichiosis. Despite the induction of an active host immune response, the pathogen has evolved to persist in its vertebrate and tick hosts. Understanding how the organism progresses in tick and vertebrate host cells is critical in identifying effective strategies to block the pathogen transmission. Our recent molecular and proteomic studies revealed differences in numerous expressed proteins of the organism during its growth in different host environments. Methodology/Principal Findings: Transmission electron microscopy analysis was performed to assess morphological changes in the bacterium within macrophages and tick cells. The stages of pathogen progression observed included the attachment of the organism to the host cells, its engulfment and replication within a morulae by binary fission and release of the organisms from infected host cells by complete host cell lysis or by exocytosis. E. chaffeensis grown in tick cells was highly pleomorphic and appears to replicate by both binary fission and filamentous type cell divisions. The presence of Ehrlichia-like inclusions was also observed within the nucleus of both macrophages and tick cells. This observation was confirmed by confocal microscopy and immunoblot analysis. Conclusions/Significance: Morphological differences in the pathogen’s progression, replication, and processing within macrophages and tick cells provide further evidence that E. chaffeensis employs unique host-cell specific strategies in support of adaptation to vertebrate and tick cell environments

An Agent-Based Model of a Hepatic Inflammatory Response to Salmonella: A Computational Study under a Large Set of Experimental Data

Citation: Shi, Z. Z., Chapes, S. K., Ben-Arieh, D., & Wu, C. H. (2016). An Agent-Based Model of a Hepatic Inflammatory Response to Salmonella: A Computational Study under a Large Set of Experimental Data. Plos One, 11(8), 39. doi:10.1371/journal.pone.0161131We present an agent-based model (ABM) to simulate a hepatic inflammatory response (HIR) in a mouse infected by Salmonella that sometimes progressed to problematic proportions, known as "sepsis". Based on over 200 published studies, this ABM describes interactions among 21 cells or cytokines and incorporates 226 experimental data sets and/or data estimates from those reports to simulate a mouse HIR in silico. Our simulated results reproduced dynamic patterns of HIR reported in the literature. As shown in vivo, our model also demonstrated that sepsis was highly related to the initial Salmonella dose and the presence of components of the adaptive immune system. We determined that high mobility group box-1, C-reactive protein, and the interleukin-10: tumor necrosis factor-a ratio, and CD4+ T cell: CD8+ T cell ratio, all recognized as biomarkers during HIR, significantly correlated with outcomes of HIR. During therapy-directed silico simulations, our results demonstrated that anti-agent intervention impacted the survival rates of septic individuals in a time-dependent manner. By specifying the infected species, source of infection, and site of infection, this ABM enabled us to reproduce the kinetics of several essential indicators during a HIR, observe distinct dynamic patterns that are manifested during HIR, and allowed us to test proposed therapy-directed treatments. Although limitation still exists, this ABM is a step forward because it links underlying biological processes to computational simulation and was validated through a series of comparisons between the simulated results and experimental studies

DOES MODERATE INTENSITY EXERCISE ATTENUATE THE POST-PRANDIAL LIPEMIC AND AIRWAY INFLAMMATORY RESPONSE TO A HIGH FAT MEAL?

Stephanie P. Kurti1, Sara K. Rosenkranz2, Stephen K. Chapes3, Morton Levitt4, Brooke J. Cull2, Colby S. Teeman2, Sam R. Emerson2 & Craig A. Harms1, FACSM 1Department of Kinesiology, 2Department of Human Nutrition, 3Department of Biology, Kansas State University, Manhattan, Kansas, 4College of Medicine, Florida Atlantic University, Boca Raton, Florida Purpose: Recent reports suggest that a single high-fat meal (HFM) leads to increased airway and systemic inflammatory markers and triglycerides. However, an acute bout of exercise in the post prandial period has anti-inflammatory and lipid lowering effects. The purpose of this research was to investigate whether an acute bout of moderate intensity physical activity post-HFM would attenuate post prandial lipemia (PPL) and protect against airway inflammation in active individuals. We hypothesized that an acute bout of exercise would attenuate the increase in PPL and airway inflammation after a HFM. Methods: Twenty healthy, physically active college-aged participants (13M/7F) completed the study. Subjects were required to undergo DEXA scans, pulmonary function testing and performed an incremental exercise test to exhaustion to determine VO2peak.On the second visit, subjects were randomly assigned to a sedentary condition (CON) (n=10, 7M/3F) or moderate-intensity exercise bout (~30-45 min) that expended half of the total calories from the meal (EX; 60% VO2peak) (n=10, 6M/4F) 45 minutes after consuming the HFM (63% fat, 10kcal/kg of bodyweight). Blood lipids and airway inflammation measured via exhaled nitric oxide (eNO) were assessed at baseline, 2 hr and 4 hr post-HFM. Sputum differential cell counts were done to assess airway inflammation at baseline and 4 hr post-HFM. Results: Baseline triglycerides (CON= 66.4 ± 34.7 mg/dL; EX= 58.9 ± 20.5 mg/dL) and eNO (CON= 14.3 ± 5.9 ppb; EX= 18.6 ± 9.84 ppb) were not significantly different between conditions (p\u3e0.05). Triglycerides increased significantly in the CON 2 hr (~54%, p=0.018) and 4 hr (~107%; p=0.018) post-HFM and in the EX condition 2 hr (~66%; p=0.003) and 4 hr (~119%; p=0.004) post-HFM. Exhaled nitric oxide did not significantly increase in the CON 2 hr or 4 hr post-HFM (~17%; p=0.208; ~-2%,p=0.763, respectively) or the EX condition (2 hr= ~10%; p=0.064; 4 hr= ~12%; p=0.167). Percentage of neutrophils and eosinophils significantly increased (pConclusion:These preliminary results indicate an acute bout of moderate intensity exercise does not attenuate postprandial airway inflammation or lipemia following a HFM in physically active subjects. However, a novel finding is that active subjects show pulmonary neutrophilia 4 hours after a high fat meal, independent of increases in exhaled nitric oxide or triglycerides

Changes in Mouse Thymus and Spleen after Return from the STS-135 Mission in Space

Our previous results with flight (FLT) mice showed abnormalities in thymuses and spleens that have potential to compromise immune defense mechanisms. In this study, the organs were further evaluated in C57BL/6 mice after Space Shuttle Atlantis returned from a 13-day mission. Thymuses and spleens were harvested from FLT mice and ground controls housed in similar animal enclosure modules (AEM). Organ and body mass, DNA fragmentation and expression of genes related to T cells and cancer were determined. Although significance was not obtained for thymus mass, DNA fragmentation was greater in the FLT group (P<0.01). Spleen mass alone and relative to body mass was significantly decreased in FLT mice (P<0.05). In FLT thymuses, 6/84 T cell-related genes were affected versus the AEM control group (P<0.05; up: IL10, Il18bp, Il18r1, Spp1; down: Ccl7, IL6); 15/84 cancer-related genes had altered expression (P<0.05; up: Casp8, FGFR2, Figf, Hgf, IGF1, Itga4, Ncam1, Pdgfa, Pik3r1, Serpinb2, Sykb; down: Cdc25a, E2F1, Mmp9, Myc). In the spleen, 8/84 cancer-related genes were affected in FLT mice compared to AEM controls (P<0.05; up: Cdkn2a; down: Birc5, Casp8, Ctnnb1, Map2k1, Mdm2, NFkB1, Pdgfa). Pathway analysis (apoptosis signaling and checkpoint regulation) was used to map relationships among the cancer–related genes. The results showed that a relatively short mission in space had a significant impact on both organs. The findings also indicate that immune system aberrations due to stressors associated with space travel should be included when estimating risk for pathologies such as cancer and infection and in designing appropriate countermeasures. Although this was the historic last flight of NASA’s Space Shuttle Program, exploration of space will undoubtedly continue