Vaccine against Streptococcus suis Infection in Pig Based on Alternative Carrier Protein Conjugate.

Streptococcus suis is a serious pathogen in the pig industry with zoonotic potential. With respect to the current effort to reduce antibiotic use in animals, a prophylactic measure is needed to control the disease burden. Unfortunately, immunization against streptococcal pathogens is challenging due to nature of the interaction between the pathogen and the host immune system, but vaccines based on conjugates of capsular polysaccharide (CPS) and carrier protein were proved to be efficient. The main obstacle of these vaccines is manufacturing cost, limiting their use in animals. In this work, we tested an experimental vaccine against Streptococcus suis serotype 2 based on capsular polysaccharide conjugated to chicken ovalbumin (OVA) and compared its immunogenicity and protectivity with a vaccine based on CRM197 conjugate. Ovalbumin was selected as a cheap alternative to recombinant carrier proteins widely used in vaccines for human use. We found that the ovalbumin-based experimental vaccine successfully induced immune response in pigs, and the IgG antibody response was even higher than after immunization with capsular polysaccharide-CRM197 conjugate. Protectivity of vaccination against infection was evaluated in the challenge experiment and was found promising for both conjugates.

Identification and partial characterization of a novel serpin from Eudiplozoon nipponicum (Monogenea, Polyopisthocotylea).

BACKGROUND: Serpins are a superfamily of serine peptidase inhibitors that participate in the regulation of many physiological and cell peptidase-mediated processes in all organisms (e.g. in blood clotting, complement activation, fibrinolysis, inflammation, and programmed cell death). It was postulated that in the blood-feeding members of the monogenean family Diplozoidae, serpins could play an important role in the prevention of thrombus formation, activation of complement, inflammation in the host, and/or in the endogenous regulation of protein degradation. RESULTS: In silico analysis showed that the DNA and primary protein structures of serpin from Eudiplozoon nipponicum (EnSerp1) are similar to other members of the serpin superfamily. The inhibitory potential of EnSerp1 on four physiologically-relevant serine peptidases (trypsin, factor Xa, kallikrein, and plasmin) was demonstrated and its presence in the worm's excretory-secretory products (ESPs) was confirmed. CONCLUSION: EnSerp1 influences the activity of peptidases that play a role in blood coagulation, fibrinolysis, and complement activation. This inhibitory potential, together with the serpin's presence in ESPs, suggests that it is likely involved in host-parasite interactions and could be one of the molecules involved in the control of feeding and prevention of inflammatory responses.

Epitope mapping of Borrelia burgdorferi OspC protein in homodimeric fold.

In current work, we used recombinant OspC protein derived from B. afzelii strain BRZ31 in the native homodimeric fold for mice immunization and following selection process to produce three mouse monoclonal antibodies able to bind to variable parts of up to five different OspC proteins. Applying the combination of mass spectrometry assisted epitope mapping and affinity based theoretical prediction we have localized regions responsible for antigen-antibody interactions and approximate epitopes' amino acid composition. Two mAbs (3F4 and 2A9) binds to linear epitopes located in previously described immunogenic regions in the exposed part of OspC protein. The third mAb (2D1) recognises highly conserved discontinuous epitope close to the ligand binding domain 1.

DNA-based identification and OspC serotyping in cultures of Borrelia burgdorferi s.l. isolated from ticks collected in the Moravia (Czech Republic).

Two different genetic loci, flaB and ospC, were employed to assign genospecies and OspC phylogenetic type to 18 strains isolated from ticks collected in Pisárky, a suburban park in the city of Brno, Czech Republic. The RFLP analysis revealed three different genospecies (B. afzelii, B. garinii, and B. valaisiana). Three samples from the collection contained more than one genospecies. In the other 15 strains, nucleotide sequences of flaB and ospC were determined. The following phylogenetic analysis assigned 12 isolates to genospecies B. garinii and three to B. afzelii. These isolates were further subdivided into seven distinct ospC groups. The most related OspC types were G2, G4, and G5 (B. garinii) and A3 and A8 (B. afzelii).

The occurrence of Borrelia burgdorferi sensu lato in certain ectoparasites (Mesostigmata, Siphonaptera) of Apodemus flavicollis and Myodes glareolus in chosen localities in the Czech Republic.

Ticks represent the primary vectors of several serious diseases, including the Lyme disease caused by Borrelia burgdorferi sensu lato (Bbsl). In this study two dominant ectoparasitic groups of arthropods (Mesostigmata, Siphonaptera) were investigated for the presence of borrelian DNA in order to determine their potential role of vectors (or carriers) of this bacterium. All individuals (235) were collected from wild-living rodents obtained in three localities in the Czech Republic (Bazantula, Baba and Krizovice). The majority of parasites were members of the families Parasitidae and Dermanyssidae (Mesostigmata) and families Hystrichopsyllidae and Ceratophyllidae (Siphonaptera). The rodent host species was almost exclusively the yellow-necked mouse (Apodemus flavicollis). Bbsl was detected by the PCR method in the following ectoparasite species: Euryparasitus emarginatus (1), Eulaelaps stabularis (1), Haemogamassus nidi (1), Laelaps agilis (5), Myonyssus gigas (1) (Mesostigmata) and Ctenophthalmus agyrtes (1), C. solutus (3) (Siphonaptera).

[Monitoring the prevalence of pathogenic Borrelia burgdorferi sensu lato in ticks in two Brno locations]. / Monitoring prevalence patogenní Borrelia burgdorferi sensu lato v klíst'atech ve dvou lokalitach v Brne.

OBJECTIVE: The aim of the article is to present the results of monitoring the prevalence of the spirochete Borrelia burgdorferi sensu lato (Bbsl) in Ixodes ricinus ticks in two different locations in the city of Brno, Pisárky and Zamilovaný hájek (ZH). At the same time, factors potentially affecting the activity of ticks in these locations were studied. Results of the monitoring carried out in the first three spring months of the year 2011 are compared with 2010 results. MATERIAL AND METHODS: In 2010-2011, Ixodes ricinus ticks were periodically sampled in two locations in Brno by flagging. Ticks were investigated by dark field microscopy (DFM) for the presence of spirochetes. DFM-positive samples from 2010 were tested by PCR to identify Bbsl. RESULTS: In the first three spring months (March-May) of 2011, a total of 234 ticks were collected in Pisárky and 211 ticks in ZH. Positive samples detected by DFM accounted for 5.56 % in Pisárky and 25.12 % in ZH. PCR confirmed Bbsl in at least 75 %. Statistical analysis confirmed the dependence of tick activity on the air temperature in both locations. CONCLUSION: Within the same city, seroprevalence was found to be different in two locations. High seroprevalence in ZH (25.12 %) could be attributed to focal spread of the disease from several sources, both ticks and reservoirs such as rodents. This may results in unfavourable epidemiological situation in Brno. On the other hand, the seroprevalence rates in Pisárky are consistent with findings from an earlier long-term study.

What is the percentage of pathogenic borreliae in spirochaetal findings of mosquito larvae?

In this study, larvae (1,179 ex.) of mosquito genera Culex were examined for the presence of spirochaetes by Dark Field Microscopy (DFM) at the locality of Blansko (Czech Republic) in of 2004-2008. DFM spirochaete positive samples (25.4 %) were investigated by nested PCR; only 4 samples were positive for the presence of Borrelia burgdorferi sensu lato, which is 0.3 % of the total examined samples. We can conclude that only a low percentage of pathogenic borreliae are presented in mosquito larvae, while the spirochaete of undefined genera infect larvae in high amounts.