Epidemiological significance of the domestic Black Pig ( Sus scrofa) in the maintenance of Bovine Tuberculosis in Sicily

Bovine tuberculosis (bTB) is an emerging disease among wild animals in many parts of the world. Wildlife reservoir hosts may thus represent a potential source of infection for livestock and humans. We investigated the role played by the Sicilian black pig, an autochthonous free- or semi-free-ranging domestic pig breed, as a potential source of bTB infection in an area where bTB prevalence in cattle is high. We initially performed a preliminary field study to assess the occurrence of bTB in such animals. We sampled 119 pigs at abattoir and found 6.7% and 3.4% of them to be affected by gross tuberculous-like lesions (TBL) and Mycobacterium bovis culture positive, respectively. We then proceeded to investigate the dissemination and characteristics of lesions in a second field study performed on 100 animals sampled from infected herds. Here, tissues collected at the abattoir were examined macroscopically, microscopically, and by culture tests. Most pigs with TBL showed generalized lesions in both gross and histological examinations (53% and 65.5%, respectively). Head lymph nodes were the most frequently affected in both localized and generalized TB cases observed macroscopically and microscopically. M. bovis was the most frequently isolated etiologic agent. The molecular characterization of isolates from both field studies by spoligotyping and analysis of 12 mycobacterial interspersed repetitive-unit–variable number tandem repeat (MIRU-VNTR) loci, followed by their comparison to isolates of cattle origin, suggested a potential transmission of mycobacteria from domestic animals to black pigs and vice versa. Our findings, along with ethological, ecological, and management considerations, suggest that the black pig might act as a bTB reservoir in the ecosystem under study. However, additional studies will be necessary to establish the true epidemiological significance of the Sicilian black pig

Salmonella enterica Serovar Typhimurium Lacking hfq Gene Confers Protective Immunity against Murine Typhoid

Salmonella enterica is an important enteric pathogen and its various serovars are involved in causing both systemic and intestinal diseases in humans and domestic animals. The emergence of multidrug-resistant strains of Salmonella leading to increased morbidity and mortality has further complicated its management. Live attenuated vaccines have been proven superior over killed or subunit vaccines due to their ability to induce protective immunity. Of the various strategies used for the generation of live attenuated vaccine strains, focus has gradually shifted towards manipulation of virulence regulator genes. Hfq is a RNA chaperon which mediates the binding of small RNAs to the mRNA and assists in post-transcriptional gene regulation in bacteria. In this study, we evaluated the efficacy of the Salmonella Typhimurium Δhfq strain as a candidate for live oral vaccine in murine model of typhoid fever. Salmonella hfq deletion mutant is highly attenuated in cell culture and animal model implying a significant role of Hfq in bacterial virulence. Oral immunization with the Salmonella hfq deletion mutant efficiently protects mice against subsequent oral challenge with virulent strain of Salmonella Typhimurium. Moreover, protection was induced upon both multiple as well as single dose of immunizations. The vaccine strain appears to be safe for use in pregnant mice and the protection is mediated by the increase in the number of CD4+ T lymphocytes upon vaccination. The levels of serum IgG and secretory-IgA in intestinal washes specific to lipopolysaccharide and outer membrane protein were significantly increased upon vaccination. Furthermore, hfq deletion mutant showed enhanced antigen presentation by dendritic cells compared to the wild type strain. Taken together, the studies in murine immunization model suggest that the Salmonella hfq deletion mutant can be a novel live oral vaccine candidate

VALUTAZIONE DELLA RISPOSTA IMMUNITARIA ALLA VACCINAZIONE CONTRO C. pseudotuberculosis IN UN ALLEVAMENTO DI ALPACA IN ITALIA: RISULTATI PRELIMINARI

The applicability of some assay to evaluate the effectiveness of immune function, as previously used in other animal species (pigs, cows and shhep), was tested in an alpaca (Lama pacos) herd affected by Caseous Lymphadenitis (Corynebacterium pseudotuberculosis) and subject to a vaccination programme against the causative agent. The vaccination programme was initiated following failure of controlling the outbreak by isolation and treatment of the initially infected animals. An homotypic, autogenous inactivated and adjuvated (aluminium hydroxide) vaccine, administered subcutaneously at day 0 (A) and after 21 days (B) was used. Blood samples were collected by venipuncture of the jugular vein on days 0, 21 and 42 (C) and serum obtained from these whole blood samples was tested for: Lysozyme serum titratio (expressed in microg/ml), serum Bactericidial assay (expressed in %) , semiquantitative complement titration (expressed in CH50) and IgGs concentrations (by Radial immunodifusion test)

Proteomic analysis of protein purified derivative of Mycobacterium bovis.

BACKGROUND: Tuberculin skin test based on in vivo intradermal inoculation of purified protein derivative from Mycobacterium bovis (bPPD) is the diagnostic test for the control and surveillance of bovine tuberculosis (bTB). METHODS: Proteomic analysis was performed on different bPPD preparations from M. bovis, strain AN5. Proteins were precipitated from bPPD solutions by TCA precipitation. The proteome of bPPD preparations was investigated by bottom-up proteomics, which consisted in protein digestion and nano-LC-MS/MS analysis. Mass spectrometry analysis was performed on a Q-exactive hybrid quadrupole-Orbitrap mass spectrometer coupled online to an Easy nano-LC1000 system. RESULTS: Three hundred and fifty-six proteins were identified and quantified by at least 2 peptides (99% confidence per peptide). One hundred and ninety-eight proteins, which had not been previously described, were detected; furthermore, the proteomic profile shared 80 proteins with previous proteomes from bPPDs from the United Kingdom and Brazil and 139 protein components from bPPD from Korea. Locus name of M. bovis (Mb) with orthologs from M. tuberculosis H37Rv, comparative gene and protein length, molecular mass, functional categories, gene name and function of each protein were reported. Ninety-two T cell mycobacterial antigens responsible for delayed-type hypersensitivity were detected, fifty-two of which were not previously reported in any bPPD proteome. Data are available via ProteomeXchange with identifier PXD005920. CONCLUSIONS: This study represents the highest proteome coverage of bPPD preparations to date. Since proteins perform cellular functions essential to health and/or disease, obtaining knowledge of their presence and variance is of great importance in understanding disease states and for advancing translational studies. Therefore, to better understand Mycobacterium tuberculosis complex biology during infection, survival, and persistence, the reproducible evaluation of the proteins that catalyze and control these processes is critically important. More active and more specific tuberculins would be desirable. Indeed, many antigens contained within bPPD are currently responsible for the cross-reactivity resulting in false-positive results as they are shared between non-tuberculous and tuberculous mycobacteria

EVALUATION OF THE IMMUNE RESPONSE TO VACCINATION AGAINST C. PSEUDOTUBERCOLOSIS IN AN ALPACA HERD IN ITALY: PRELIMINARY RESULTS.

The applicability of some assays to evaluate the effectiveness of the immune function, as previously used in other animal species (pigs, cows and sheep), was tested in an alpaca (Lama pacos) herd affected by Caseous Lymphadenitis (Corynebacterium pseudotubercolosis) and subject to a vaccination programme against the causative agent. The vaccination programme was initiated following failure of controlling the outbreak by isolation and treatment of the initially affected animals. An homotypic, autogenous inactivated and adjuvated (aluminium hydroxide) vaccine, administered subcutaneously at day 0 (A) and after 21 days (B) was used. Blood samples were collected by venipuncture of the jugular vein on days 0, 21 and 42 (C). Samples in EDTA, collected on day A and C, were analysed for standard haematological parameters. Serum obtained from whole blood with no anticoagulant on days A, B and C was tested for: Lysozyme serum titration (expressed in mu g/m), serum Bactericidal assay (expressed in %), semiquantitative complement titration (expressed in CH50) and immunoglobuline (by electrophoresis) and IgGs concentrations (by Radial Immunodiffusion tests)