30 research outputs found
Human Flt3L Generates Dendritic Cells from Canine Peripheral Blood Precursors: Implications for a Dog Glioma Clinical Trial
Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults and carries a dismal prognosis. We have developed a conditional cytotoxic/immunotherapeutic approach using adenoviral vectors (Ads) encoding the immunostimulatory cytokine, human soluble fms-like tyrosine kinase 3 ligand (hsFlt3L) and the conditional cytotoxic molecule, i.e., Herpes Simplex Type 1- thymide kinase (TK). This therapy triggers an anti-tumor immune response that leads to tumor regression and anti-tumor immunological memory in intracranial rodent cancer models. We aim to test the efficacy of this immunotherapy in dogs bearing spontaneous GBM. In view of the controversy regarding the effect of human cytokines on dog immune cells, and considering that the efficacy of this treatment depends on hsFlt3L-stimulated dendritic cells (DCs), in the present work we tested the ability of Ad-encoded hsFlt3L to generate DCs from dog peripheral blood and compared its effects with canine IL-4 and GM-CSF.Our results demonstrate that hsFlT3L expressed form an Ad vector, generated DCs from peripheral blood cultures with very similar morphological and phenotypic characteristics to canine IL-4 and GM-CSF-cultured DCs. These include phagocytic activity and expression of CD11c, MHCII, CD80 and CD14. Maturation of DCs cultured under both conditions resulted in increased secretion of IL-6, TNF-alpha and IFN-gamma. Importantly, hsFlt3L-derived antigen presenting cells showed allostimulatory potential highlighting their ability to present antigen to T cells and elicit their proliferation.These results demonstrate that hsFlt3L induces the proliferation of canine DCs and support its use in upcoming clinical trials for canine GBM. Our data further support the translation of hsFlt3L to be used for dendritic cells' vaccination and gene therapeutic approaches from rodent models to canine patients and its future implementation in human clinical trials
SIVagm Infection in Wild African Green Monkeys from South Africa: Epidemiology, Natural History, and Evolutionary Considerations
Pathogenesis studies of SIV infection have not been performed to date in wild monkeys due to difficulty in collecting and storing samples on site and the lack of analytical reagents covering the extensive SIV diversity. We performed a large scale study of molecular epidemiology and natural history of SIVagm infection in 225 free-ranging AGMs from multiple locations in South Africa. SIV prevalence (established by sequencing pol, env, and gag) varied dramatically between infant/juvenile (7%) and adult animals (68%) (p<0.0001), and between adult females (78%) and males (57%). Phylogenetic analyses revealed an extensive genetic diversity, including frequent recombination events. Some AGMs harbored epidemiologically linked viruses. Viruses infecting AGMs in the Free State, which are separated from those on the coastal side by the Drakensberg Mountains, formed a separate cluster in the phylogenetic trees; this observation supports a long standing presence of SIV in AGMs, at least from the time of their speciation to their Plio-Pleistocene migration. Specific primers/probes were synthesized based on the pol sequence data and viral loads (VLs) were quantified. VLs were of 104-106 RNA copies/ml, in the range of those observed in experimentally-infected monkeys, validating the experimental approaches in natural hosts. VLs were significantly higher (107-108 RNA copies/ml) in 10 AGMs diagnosed as acutely infected based on SIV seronegativity (Fiebig II), which suggests a very active transmission of SIVagm in the wild. Neither cytokine levels (as biomarkers of immune activation) nor sCD14 levels (a biomarker of microbial translocation) were different between SIV-infected and SIV-uninfected monkeys. This complex algorithm combining sequencing and phylogeny, VL quantification, serology, and testing of surrogate markers of microbial translocation and immune activation permits a systematic investigation of the epidemiology, viral diversity and natural history of SIV infection in wild African natural hosts. © 2013 Ma et al
Environmental effects of ozone depletion, UV radiation and interactions with climate change : UNEP Environmental Effects Assessment Panel, update 2017
Peer reviewe
Production of mouse monoclonal antibodies to Pasteurella multocida type A and the immunological properties of a protective anti-lipopolysaccharide antibody
PCR detection and analysis of Pasteurella multocida from the tonsils of slaughtered pigs in Vietnam
A total of 36 tonsil swab samples were collected from healthy swine prior to slaughter at the abattoirs in Can tho and Tien giang provinces of Southern Vietnam, The presence of Pasteurella multocida in these samples was detected by the combination of direct cultivation and isolation, mouse inoculation and the polymerase chain reaction (PM-PCR). P. multocida was detected in 16 samples by PCR, with 17 strains ultimately isolated. All samples were negative for serogroup B by HSB-PCR and conventional serotyping, with isolates identified as A:3, D:1 or D:3. In addition, all samples were determined to be negative for the P. multocida toxin (PMT). Characterisation of isolated P, multocida by REP-PCR and biotyping revealed nine distinct REP profiles and seven biotypes among the 17 isolates. Some correlation was seen with P. multocida isolated from a previous Australian outbreak of acute swine pasteurellosis, and those isolated from fowl cholera outbreaks in Vietnamese poultry. (C) 2000 Elsevier Science B.V. All rights reserved
Nutritional status among primary school children in rural Sri Lanka; a public health challenge for a country with high child health standards
Abstract Background Nutritional status of pre adolescent children is not widely studied in Sri Lanka. The purpose of this study was to determine the nutritional status among pre-adolescent school children in a rural province of Sri Lanka. Methods A school based cross sectional study was carried out in North Central Province in 100 rural schools, selected using multi stage cluster sampling with probability proportionate to size. Children in grade one to five were enrolled with a maximum cluster size of fifty. Anthropometric measurements were done by trained data collectors and venesection was done at site by trained nurses. WHO AnthoPlus was used to calculate the BMI, height for age and weight for age Z scores. Survey design adjusted prevalence estimates with linearized standard errors were generated using svy function of STATA. Mean haemoglobin concentration (Hb) was calculated using methaeamoglobin method. Screening for iron deficiency and thalassemia trait was done using peripheral blood films. Results Height and weight measurements were done for 4469 of children and the Hb data was available for 4398 children. Based on the survey design adjusted estimates, prevalence of severe thinness, thinness, overweight and obesity in this population was 8.60% (SE 0.94), 2.91%(SE 0.74), 2.95%(0.26) and 2.43%(SE 0.92) respectively. Similarly, survey design adjusted prevalence of underweight and stunting were, 25.93% (95% CI 24.07–27.89%) and 43.92%(95% CI 40.55–47.56%). Adjusted mean estimates for hemoglobin was 12.20 (95% CI 12.16–12.24) g/dL. Prevalence of anemia was 17.3% (n = 749). Prevalence of mild and moderate anemia was 9.4 and 7.6% respectively. Conclusion This study confirms that malnutrition is still a major problem in North Central Province, Sri Lanka