Pasteurellaceae

Abstract: The reservoir of eighty-one taxa/groups classified with the family Pasteurellaceae Pohl 1981 is reviewed based upon published data and own investigations. With the exception of certain strains of P. multocida, A. pleuropneumoniae and [H.] paragallinarum organisms belonging to this family are usually regarded as opportunistic, secondary invaders which under normal conditions coexist peacefully with the animal host on mucosal membranes of the upper respiratory- and lower genital tracts. Very little is known about factors that govern the ecological preferences that certain members of this family show for specific surfaces and hosts. Mechanisms of colonization, survival and multiplication, invasion and pathogenic action are incompletely understood. The significance of Pasteurellaceae in animals and man has recently been reviewed. Subsequent publications have underlined the significance of biovars 2 of P. canis and P. avium and ornithine negative P. multocida in pneumonia in cattle. In addition, differences in pathogenicity have been demonstrated for different serovars of [H.] parasuis. The disease potential of many taxa/groups is only incompletely known.

Abstract: Pasteurellaceae comprise a large and diverse family of Gram-negative bacteria with members ranging from important pathogens such as Haemophilus influenzae to commensals of the animal and human mucosa. Information on the biology of these organisms has mushroomed in recent years, driven by the development of novel genetic and molecular methodologies. Since 1995, the family has been expanded from three genera to the current thirteen through the use of new genetic-based classification and identification technologies. Many members of the Pasteurellaceae family make excellent natural models for the study of bacterial pathogenesis and host-pathogen-interactions thus giving valuable insights into related human diseases. Research in this area is at a very exciting stage. In this timely book, leading international Pasteurellaceae scientists critically review the most important current research providing an up-to-date review of the molecular biology, genomics and virulence of these fascinating organisms. Topics covered include taxonomy and biodiversity, phylogeny, comparative genomics, competence, DNA uptake and transformation, proteomics and protein secretion, RTX toxins, lipopolysaccharides, biofilms, quorum sensing, antimicrobial resistance, diagnosis, and OMP and iron uptake. Each chapter is independent and can be read in isolation and as a whole the book provides an important resource summarising our current knowledge of Pasteurellaceae genomics and molecular biology. Essential reading for everyone working on Pasteurellaceae and related organisms.

Abstract: Invited Papers: Taxononomy of the Family Pasteurellaceae Pohl 1981 (M. Bisgaard). Haemorrhagic Septicaemia (Pasteurella multocida Serotype B:2 and E:2 Infection) in Cattle and Buffalos (M.C.L. de Alwis). Vaccine Development against Pasteurella haemolytica Infections in Sheep (W. Donachie). Viralbacterial Synergistic Interactions/Pathogenesis in Cattle (L.A. Babiuk et al.). Pathogenesis and Virulence of Pasteurella haemolytica in Cattle: An Analysis of Current Knowledge and Future Approaches (A.W. Confer et al.). Haemophilus somnus: Antigen Analysis and Immune Responses (L.B. Corbeil et al.). Liposaccharides and Capsules of the HAP Group Bacteria (B. Fenwick). Adhesin-Receptor Interactions by Haemophilus influenzae and Other Bacteria from the HAP Group (L. van Alphen). Exotoxins of Actinobacillus pleuropneumoniae (J. Frey). Receptormediated Iron Acquisition from Transferrin in the Pasteurellaceae (S.D. Kirby et al.). Molecular Studies of Antigens in HAP Organisms (R.Y.C. Lo). Modulation of Leukocytes by Exotoxins Produced by HAP Organisms (C.J. Czuprynski). Workshop Summary: Genetic Manipulations of Members of the Family Pasteurellaceae (J. Frey, J.I. MacInnes). 3 additional articles. Abstracts. Index.

Abstract: The role of the capsule of Haemophilus (Actinobacillus) pleuropneumoniae serotype 5 in bacterial virulence, and the protective efficacy of antibody to serotype 5 capsule was investigated. Encapsulated H. pleuropneumoniae serotype 5 were resistant to killing by complement and antibody to capsule or somatic antigens, whereas a noncapsulated mutant was sensitive to killing by the alternative complement pathway alone. Antiserum to whole H. pleuropneumoniae serotype 5 bacteria or monospecific antiserum to capsule was capable of opsonizing bacteria of the homologous serotype for phagocytosis by swine polymorphonuclear leukocytes but was not opsonic for a heterologous serotype. An immunoglobulin M monoclonal antibody to the serotype 5 capsule was not opsonic for any serotype. Mice were protected against lethal, intranasal challenge with the homologous or heterologous serotype after immunization with live encapsulated or noncapsulated bacteria, but not after immunization with killed bacteria, lipopolysaccharide, or a capsule-protein conjugate vaccine. The protection induced by immunization with live bacteria was transferred to nonimmune, syngeneic mice by serum but not by spleen cells. Nonimmune pigs passively immunized with monospecific swine serum to capsule were protected from lethal infection but not from development of hemorrhagic lung lesions, whereas pigs passively immunized with swine antiserum to live bacteria did not develop severe respiratory lesions. Thus, the capsule of H. pleuropneumoniae serotype 5 was inhibitory to the bactericidal activity of serum and was antiphagocytic. Antibody to the capsule was opsonic but was not fully protective.