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We sought to identify a usable biomarker from blood samples to characterize early-stage Alzheimer’s disease (AD) patients, in order to facilitate rapid diagnosis, early therapeutic intervention, and monitoring of clinical trials. We compared metabolites from blood plasma in early-stage Alzheimer’s disease patients with blood plasma from healthy controls using two different analytical platforms: Amino Acid Analyzer and Tandem Mass-Spectrometer. Early-stage Alzheimer’s patient blood samples were obtained during an FDA-approved Phase IIa clinical trial (Clinicaltrial.gov NCT03062449). Participants included 25 early-stage Alzheimer’s patients and 25 healthy controls in the United States. We measured concentrations of 2-aminoethyl dihydrogen phosphate and taurine in blood plasma samples. We found that plasma concentrations of a phospholipid metabolite, 2-aminoethyl dihydrogen phosphate, normalized by taurine concentrations, distinguish blood samples of patients with early-stage AD. This possible new Alzheimer’s biomarker may supplement clinical diagnosis for early detection of the disease.

Archaeosomes are liposomes traditionally comprised of total polar lipids (TPL) or semi-synthetic glycerolipids of ether-linked isoprenoid phytanyl cores with varied glyco- and amino-head groups. As adjuvants, they induce robust, long-lasting humoral and cell-mediated immune responses and enhance protection in murine models of infectious disease and cancer. Traditional total polar lipid (TPL) archaeosome formulations are relatively complex and first generation semi-synthetic archaeosomes involve many synthetic steps to arrive at the final desired glycolipid composition. We have developed a novel archaeosome formulation comprising a sulfated disaccharide group covalently linked to the free sn-1 hydroxyl backbone of an archaeal core lipid (sulfated S-lactosylarchaeol, SLA) that can be more readily synthesized yet retains strong immunostimulatory activity for induction of cell-mediated immunity following systemic immunization. Herein, we have evaluated the immunostimulatory effects of SLA archaeosomes when used as adjuvant with ovalbumin (OVA) and hepatitis B surface antigen (HBsAg) and compared this to various other adjuvants including TLR3/4/9 agonists, oil-in-water and water-in-oil emulsions and aluminum hydroxide. Overall, we found that semi-synthetic sulfated glycolipid archaeosomes induce strong Ag-specific IgG titers and CD8 T cells to both antigens. In addition, they induce the expression of a number of cytokines/chemokines including IL-6, G-CSF, KC & MIP-2. SLA archaeosome formulations demonstrated strong adjuvant activity, superior to many of the other tested adjuvants.

Forest loss in hotspots around the world impacts not only local climate where loss occurs, but also influences climate and vegetation in remote parts of the globe through ecoclimate teleconnections. The magnitude and mechanism of remote impacts likely depends on the location and distribution of forest loss hotspots, but the nature of these dependencies has not been investigated. We use global climate model simulations to estimate the distribution of ecologically-relevant climate changes resulting from forest loss in two hotspot regions: western North America (wNA), which is experiencing accelerated dieoff, and the Amazon basin, which is subject to high rates of deforestation. The remote climatic and ecological net effects of simultaneous forest loss in both regions differed from the combined effects of loss from the two regions simulated separately, as evident in three impacted areas. Eastern South American Gross Primary Productivity (GPP) increased due to changes in seasonal rainfall associated with Amazon forest loss and changes in temperature related to wNA forest loss. Eurasia’s GPP declined with wNA forest loss due to cooling temperatures increasing soil ice volume. Southeastern North American productivity increased with simultaneous forest loss, but declined with only wNA forest loss due to changes in VPD. Our results illustrate the need for a new generation of local-to-global scale analyses to identify potential ecoclimate teleconnections, their underlying mechanisms, and most importantly, their synergistic interactions, to predict the responses to increasing forest loss under future land use change and climate change.

In previous work from our laboratories a synthetic gene encoding a peptide ("Sulpeptide 1" or "S1") with a high proportion of methionine and cysteine residues had been designed to act as a sulfur sink and was inserted into the dsz (desulfurization) operon of Rhodococcus erythropolis IGTS8. In the work described here this construct (dszAS1BC) and the intact dsz operon (dszABC) cloned into vector pRESX under control of the (Rhodococcus) kstD promoter were transformed into the desulfurization-negative strain CW25 of Rhodococcus qingshengii. The resulting strains (CW25[pRESX-dszABC] and CW25[pRESX-dszAS1BC]) were subjected to adaptive selection by repeated passages at log phase (up to 100 times) in minimal medium with dibenzothiophene (DBT) as sole sulfur source. For both strains DBT metabolism peaked early in the selection process and then decreased, eventually averaging four times that of the initial transformed cells; the maximum specific activity achieved by CW25[pRESX-dszAS1BC] exceeded that of CW25[pRESX-dszABC]. Growth rates increased by 7-fold (CW25[pRESX-dszABC]) and 13-fold (CW25[pRESX-dszAS1BC]) and these increases were stable. The adaptations of CW25[pRESX-dszAS1BC] were correlated with a 3-5X increase in plasmid copy numbers from those of the initial transformed cells; whole genome sequencing indicated that during its selection processes no mutations occurred to any of the dsz, S1, or other genes and promoters involved in sulfur metabolism, stress response, or DNA methylation, and that the effect of the sulfur sink produced by S1 is likely very small compared to the cells' overall cysteine and methionine requirements. Nevertheless, a combination of genetic engineering using sulfur sinks and increasing Dsz capability with adaptive selection may be a viable strategy to increase biodesulfurization ability.

UCS proteins have been proposed to operate as co-chaperones that work with Hsp90 in the de novo folding of myosin motors. The fission yeast UCS protein Rng3p is essential for actomyosin ring assembly and cytokinesis. Here we investigated the role of Rng3p in fission yeast myosin-II (Myo2p) motor activity. Myo2p isolated from an arrested rng3-65 mutant was capable of binding actin, yet lacked stability and activity based on its expression levels and inactivity in ATPase and actin filament gliding assays. Myo2p isolated from a myo2-E1 mutant (a mutant hyper-sensitive to perturbation of Rng3p function) showed similar behavior in the same assays and exhibited an altered motor conformation based on limited proteolysis experiments. We propose that Rng3p is not required for the folding of motors per se, but instead works to ensure the activity of intrinsically unstable myosin-II motors. Rng3p is specific to conventional myosin-II and the actomyosin ring, and is not required for unconventional myosin motor function at other actin structures. However, artificial destabilization of myosin-I motors at endocytic actin patches (using a myo1-E1 mutant) led to recruitment of Rng3p to patches. Thus, while Rng3p is specific to myosin-II, UCS proteins are adaptable and can respond to changes in the stability of other myosin motors.

BACKGROUND: Male and female avian brood parasites are subject to different selection pressures: males compete for mates but do not provide parental care or territories and only females locate hosts to lay eggs. This sex difference may affect brain architecture in some avian brood parasites, but relatively little is known about their sensory systems and behaviors used to obtain sensory information. Our goal was to study the visual resolution and visual information gathering behavior (i.e., scanning) of brown-headed cowbirds. METHODOLOGY/PRINCIPAL FINDINGS: We measured the density of single cone photoreceptors, associated with chromatic vision, and double cone photoreceptors, associated with motion detection and achromatic vision. We also measured head movement rates, as indicators of visual information gathering behavior, when exposed to an object. We found that females had significantly lower density of single and double cones than males around the fovea and in the periphery of the retina. Additionally, females had significantly higher head-movement rates than males. CONCLUSIONS: Overall, we suggest that female cowbirds have lower chromatic and achromatic visual resolution than males (without sex differences in visual contrast perception). Females might compensate for the lower visual resolution by gazing alternatively with both foveae in quicker succession than males, increasing their head movement rates. However, other physiological factors may have influenced the behavioral differences observed. Our results bring up relevant questions about the sensory basis of sex differences in behavior. One possibility is that female and male cowbirds differentially allocate costly sensory resources, as a recent study found that females actually have greater auditory resolution than males.

The virulence of F. tularensis is often associated with its ability to grow in macrophages, although recent studies show that Francisella proliferates in multiple host cell types, including pulmonary epithelial cells. Thus far little is known about the requirements for killing of F. tularensis in the non-macrophage host cell types that support replication of this organism. Here we sought to address this question through the use of a murine lung epithelial cell line (TC-1 cells). Our data show that combinations of the cytokines IFN-γ, TNF, and IL-17A activated murine pulmonary epithelial cells to inhibit the intracellular growth of the F. tularensis Live Vaccine Strain (LVS) and the highly virulent F. tularensis Schu S4 strain. Although paired combinations of IFN-γ, TNF, and IL-17A all significantly controlled LVS growth, simultaneous treatment with all three cytokines had the greatest effect on LVS growth inhibition. In contrast, Schu S4 was more resistant to cytokine-induced growth effects, exhibiting significant growth inhibition only in response to all three cytokines. Since one of the main antimicrobial mechanisms of activated macrophages is the release of reactive nitrogen intermediates (RNI) via the activity of iNOS, we investigated the role of RNI and iNOS in Francisella growth control by pulmonary epithelial cells. NOS2 gene expression was significantly up-regulated in infected, cytokine-treated pulmonary epithelial cells in a manner that correlated with LVS and Schu S4 growth control. Treatment of LVS-infected cells with an iNOS inhibitor significantly reversed LVS killing in cytokine-treated cultures. Further, we found that mouse pulmonary epithelial cells produced iNOS during in vivo respiratory LVS infection. Overall, these data demonstrate that lung epithelial cells produce iNOS both in vitro and in vivo, and can inhibit Francisella intracellular growth via reactive nitrogen intermediates.

Central memory CD8 + T cells expressing the adhesion molecule CD62L (L-selectin) are potent mediators of anti-cancer immunity due to their ability to proliferate extensively upon antigen re-stimulation. The interaction of selectin with its ligands mediates leukocyte rolling along high endothelial venules. Mice deficient in α(1,3) Fucosyltransferase IV and VII (FtDKO) lack functional L, P and E selectin ligands. Thus, we addressed whether the lack of selectin ligand interactions alters tumor protection by CD8 + T cells in FtDKO mice. Listeria monocytogenes-OVA (LM-OVA) infection evoked potent OVA-specific CD8 + T cells that proliferated and contracted at similar kinetics and phenotype in FtDKO and wild-type mice. Additionally, OVA-specific CD8 + T cells in both mouse strains exhibited similar phenotypic differentiation, in vivo cytolytic activity and IFN-γ expression. However, FtDKO mice succumbed to B16-OVA tumors significantly earlier than wild-type mice. In contrast, FtDKO mice evoked strong recall memory CD8 + T cell responses and protection to systemic LM-OVA re-challenge. The diminished tumor protection in FtDKO mice was not related to defective antigen presentation by dendritic cells or reduced proliferation of antigen-specific CD8 + T cells. However, WT or FtDKO OVA-specific CD8 + T cells showed significantly reduced ability to traffic to lymph nodes upon adoptive transfer into naïve FtDKO recipients. Furthermore, FtDKO OVA-specific CD8 + T cells displayed poor ability to infiltrate tumors growing in WT mice. These results reveal that selectin ligand expression on host endothelium as well CD8 + T cells may be important for their efficient and continued extravasation into peripheral tumors. © 2012 Stark et al.