We tested a cytokine-enhanced, multiantigen, DNA priming and poxvirus boosting vaccine regimen for prevention of malaria in the Plasmodium knowlesi-rhesus macaque model system. Animals were primed with a mixture of DNA plasmids encoding two preerythrocytic-stage proteins and two erythrocytic-stage proteins from P. knowlesi and combinations of the cytokines granulocyte-macrophage colony-stimulating factor, interleukin-4, and tumor necrosis factor alpha and were boosted with a mixture of four recombinant, attenuated vaccinia virus strains encoding the four P. knowlesi antigens. Two weeks after boosting, the geometric mean immunofluorescence titers in the immunized groups against sporozoites and infected erythrocytes ranged from 160 to 8,096 and from 1,810 to 5,120, respectively. The geometric mean anti-P. knowlesi circumsporozoite protein (PkCSP) titers ranged from 1,761 to 24,242. Peripheral blood mononuclear cells (PBMC) from the immunized monkeys produced gamma interferon (IFN-␥) in response to incubation with pooled peptides from the PkCSP at frequencies of 10 to 571 spot-forming cells/10 6 PBMC. Following challenge with 100 infectious P. knowlesi sporozoites, 2 of 11 immunized monkeys were sterilely protected, and 7 of the 9 infected monkeys resolved their parasitemias spontaneously. In contrast, all four controls became infected and required treatment for overwhelming parasitemia. Early protection was strongly associated with IFN-␥ responses against a pool of peptides from the preerythrocytic-stage antigen, PkCSP. These findings demonstrate that a multistage, multiantigen, DNA priming and poxvirus boosting vaccine regimen can protect nonhuman primates from an otherwise lethal malaria sporozoite challenge.Each year, malaria parasites infect 270 to 350 million people and kill 1.5 to 2.7 million people, mostly children in subSaharan Africa (29); drug resistance is spreading rapidly, and there is currently no licensed vaccine. In a mammalian host Plasmodium sporozoites injected by a mosquito move within minutes to hepatocytes, in which they develop during several days before emerging to infect circulating erythrocytes. Two models suggest that immune control of malaria is possible. First, in mice (15), monkeys (10), and humans (3), immunization with radiation-attenuated sporozoites can provide sterile protection against sporozoite challenge, mediated by CD8 ϩ T cells and gamma interferon (IFN-␥) directed at the intrahepatocytic stage of the parasite (6). Adults in areas where malaria is endemic develop partial clinical immunity, which is largely mediated by antibodies directed against blood-stage antigens (19,21). An effective malaria vaccine will likely need to induce both T-cell responses against infected hepatocytes and antibodies against blood-stage parasites. While DNA vaccines represent a flexible vaccine technology, well adapted to simultaneous delivery of multiple antigens, they have been less than optimally immunogenic in human trials, inducing modest Tcell responses and small amounts of antibodies or no...
Serotonin (5-HT), norepinephrine (NE), and other neurotransmitters are modulated in post-traumatic stress disorder (PTSD). In addition, pro-inflammatory cytokines (PIC) are elevated during the progression of the disorder. Currently, the only approved pharmacologic treatments for PTSD are the selective-serotonin reuptake inhibitors (SSRI) sertraline and paroxetine, but their efficacy in treating PTSD is marginal at best. In combat-related PTSD, SSRIs are of limited effectiveness. Thus, this study sought to analyze the effects of the SSRI sertraline on inflammation and neurotransmitter modulation via a predator exposure/psychosocial stress animal model of PTSD. We hypothesized that sertraline would diminish inflammatory components and increase 5-HT but might also affect levels of other neurotransmitters, particularly NE. PTSD-like effects were induced in male Sprague-Dawley rats (n = 6/group × 4 groups). The rats were secured in Plexiglas cylinders and placed in a cage with a cat for 1 h on days 1 and 11 of a 31-day stress regimen. PTSD rats were also subjected to psychosocial stress via daily cage cohort changes. At the conclusion of the stress regimen, treatment group animals were injected intraperitoneally (i.p.) with sertraline HCl at 10 mg/kg for 7 consecutive days, while controls received i.p. vehicle. The animals were subsequently sacrificed on day 8. Sertraline attenuated inflammatory markers and normalized 5-HT levels in the central nervous system (CNS). In contrast, sertraline produced elevations in NE in the CNS and systemic circulation of SSRI treated PTSD and control groups. This increase in NE suggests SSRIs produce a heightened noradrenergic response, which might elevate anxiety in a clinical setting.
Reinforcement of stapled GI anastomoses with SIS significantly increases anastomotic burst pressure. These findings suggest a role for this material in GI surgery.
Female sandflies, Phlebotomus papatasi (Scopoli) (Diptera: Psychodidae), were fed via chicken membrane on heparinized blood from eight species of mammal (human, horse, cow, pig, dog, rabbit, guinea-pig, hamster) and their reproductive success rates were compared. No appreciable differences between those fed on human and animal blood were detected with respect to the proportion of flies that fed successfully, mortality-rate within 24h, number of eggs laid per blood-fed female or egg viability. When mass-rearing sandflies for research purposes, membrane-feeding avoids practical difficulties encountered if sandflies are allowed to feed on live hosts (i.e. anaesthesia, distress from handling and postfeeding inflammation) and reduction of sandfly fecundity due to host antibody interference. Use of animal blood also eliminates risks of accidental transmission of human blood-borne pathogens, e.g. hepatitis B and human immunodeficiency virus (HIV), and is less expensive than maintenance of animals and their preparation for sandfly feeding.
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