2006 merck/merial - School of Veterinary Medicine - Louisiana State ...

jensenii, Gardnerella vaginalis, Pseudomonas aeruginosa and Gardnerella vaginalis) as well as a mixture of these purecultures.Samples from multiple locations of the vagina were examined from eight asymptomatic subjects as well as from 23symptomatic subjects. Various bacterial species were resolved by digesting PCR amplicons using bacterial primers 27fbacand 1492r and the enzymes Hae III and Msp I. T-RFLP profiles of samples from the women were compared. Vaginalbacterial diversity of the subjects was investigated and differences in diversity of the microenvironments in reference to thelocation of the samples from the vagina were evaluated.Antimicrobial activity of gallium maltolate against intracellular Rhodococcus equiNicole A. Miller,* Ronald J. Martens, Noah D. Cohen, Jessica R. Harrington, Lawrence R. BernsteinEquine Infectious Disease Laboratory, Large Animal Clinical Sciences, College of Veterinary Medicine andBiomedical Science, Texas A&M University. College Station, TXRhodococcus equi pneumonia is one of the most severe infectious diseases in foals. Infections by R. equi, afacultative intracellular pathogen of macrophages, are also becoming increasingly frequent in immunocompromised people.Evidence suggests that most foals that develop spontaneous rhodococcal pneumonia become infected within the first week oflife, when their immune systems may be immature or ineffective. There are no effective vaccines available to prevent thisdisease, and on the basis that standard vaccination protocols require several weeks to stimulate an adaptive immune response,vaccines alone would not be expected to control disease. Perinatal prophylactic administration of compounds that control R.equi in vivo may provide protection until the foal’s immune system adequately matures or an adaptive immune responsedevelops. Previous studies have shown that gallium concentrates in macrophages and inhibits the growth of extracellular R.equi in vitro by competitively inhibiting bacterial iron uptake and metabolism. This study was designed to evaluate the invitro effectiveness of gallium maltolate in suppressing growth or killing R. equi inside macrophages. Virulent R. equi (ATCC33701) were grown in media and opsonized with fresh-frozen horse serum as a source of R. equi antibody, complement, andtransferrin. R. equi were added to J774 murine macrophage-like cells in 24-well tissue culture plates at a multiplicity ofinfection of 10:1. Following phagocytosis, extracellular R. equi were removed with a series of washes, and gentamicin wasadded to the media. Gallium maltolate (GaM) (10, 50, or 100 µM) was added to macrophages either: i) overnight prior toinfection; or, ii) immediately after infection. Controls were: i) cells + bacteria without GaM; ii) cells + bacteria + maltol; iii)cells only; and, iv) cells + GaM. Treatments and controls were replicated in triplicate. Macrophages were lysed and R. equiconcentrations were determined by quantitative culture at 0, 24, 48, and 72hr. Results are pending.Gene expression analysis of peripherally circulating sorted canine dendritic cell subsetsRachel Moe; R. Curtis Bird, PhD; Bruce F. Smith, VMD, PhDScott-Ritchey Research Center, College of Veterinary Medicine, Auburn UniversityManipulation of dendritic cells (DCs), and other professional antigen presenting cells (APCs), may be the key toharnessing the immune system to defeat various disease processes. DCs can be used as vectors for autologous vaccination, orvehicles for immune modulation. DC subsets have been identified in the mouse, and these subsets may hold the key toactivating specific immune responses. DC-like subsets can be identified in the peripheral circulation of dogs by fluorescentlabeling with specific cell surface markers. To determine if these subsets express specific DC-related genes, the DC-likecells were sorted by high speed flow cytometry into four discrete populations: CD 11c+, CD4+; CD 11c+, CD8+; CD 11c+,CD4− and CD8−; and a rare and previously undescribed population of CD11c super-positive. Thesepopulations were cultured in phytohemagglutinin (PHA) activated lymphocyte conditioned media, and harvested at five andten days. Reverse transcriptase PCR (RT-PCR) and quantitative RT-PCR was used to evaluate expression of B7-1 (CD80),B7-2 (CD86), CD40, CD205, and L37 (a housekeeping gene) genes in each of the sorted populations. Initial data indicatesthat all four populations contain DC, or DC-like cells. Three of the four populations express CD205, and all four express B7-2 (CD86). QRT-PCR data is pending.Analysis of influenza virus reassortment after co-infection of pigs with two swine influenza virus subtypes,H1N1 and H3N2Teresa Negus, Wenjun Ma, Jürgen A. RichtVirus and Prion Diseases of Livestock Research Unit, National Animal Disease Center, Ames, IABackground: Swine influenza viruses have a remarkable ability for genetic shift (reassortment). Prior to 1998, SIVswere the “classical” H1N1 (cH1N1) subtype. Then, reassortant events occurred that transfered avian and human influenzagenes into cH1N1 SIVs, producing novel H3N2, H3N1, H1N2 as well as reassortant H1N1 (rH1N1) viruses. Deletions in thenonstructural protein 1 (NS1) (mutant 126) attenuate the virus and we propose it as a modified live virus (MLV) vaccine. TheMLV vaccine offers good protection against homosubtypic (H3N2) and heterosubtypic (H1N1) SIVs.Objectives: We investigated the possibility of reassortment between the H3N2-based MLV vaccine (Tx/98NS1▲126) and the H1N1 (IA/30) strain. Viruses present in lung lavage of pigs (3 and 5 days after co-infection) were plaque125