Work packages

The Paravac project is divided into Workpackages - each with a different area of responsibility.  Understanding these packages is a great way to get a detailed understanding of the project.  The projects are listed below with an outline of what each will be hoping to achieve.

Work package 1

Recombinant expression, antigen characterization and discovery

Objectives

• To express the selected candidate vaccine antigens as recombinant proteins in quantities sufficient for vaccine trials outlined in WP3.

• To discover and characterize protective antigens from Cooperia concophora.

• To establish the contribution of antigen structure, particularly glycan, to the induction of protective immunity

Description of work and role of partners

• To identify the proteins (and genes encoding) responsible for protection in the O. ostertagi L4 gut antigen fraction and to express the major antigens in recombinant form to conduct a “cocktail” vaccine trial in cattle.

• To express protective proteins from different helminths in Escherichia coli
- paramyosin and other promising vaccine antigens from D. viviparus
- established Echinococcus granulosus protective proteins Tropomyosin (EgTrp) and EgA 31 as well as novel CRISP proteins

• To express protective proteins in yeast using either Pichia pastoris or Yarrowia lipolytica or others, to enable glycosylation and to improve protein yield.

Antigens to be expressed are:

• Ostertagia ostertagi secreted proteins (OPA, 17kDa, 20kDa)

• Two Haemonchus contortus aspartyl proteases (pepsin 1 and 2)

• Lung worm (Dictyocaulus viviparus) paramyosin

• Fasciola hepatica cathepsin L1 and L2 proteases.

• Haemonchus H11 isoforms in Caenorhabditis elegans Antigen characterisation:

• To identify and purify immunodominant ES antigens from adult Cooperia oncophora • To characterise immunogenic glycans associated with the above antigens with the aim of informing choice of recombinant protein expression system.

• To identify the proteins and their encoding genes responsible for protection in the O. ostertagia L4 gut antigen fraction, to express these in recombinant form and conduct a “cocktail” vaccine trial in cattle. • To express Haemonchus H11 isoforms in C. elegans

• To express established E. granulosus protective proteins Tropomyosin (EgTrp) and EgA 31 as well as novel CRISP proteins in E. coli.

• To express selected E granulosus proteins in B subtilis

Description of deliverables

D1.1) Vaccine antigen production and characterisation: Recombinant and vaccine trials for O. ostertagi, C. oncophora, H. contortus, F. hepatica, D. viviparus and E. granulosus [month 42]

D1.2) Glycan definition on selected protective antigens: To characterise immunogenic glycans associated with the above antigens with the aim of informing choice of recombinant protein expression system. [month 36]

D1.3) Production of Bacillus subtilis (living) delivery system for E. granulosus antigens: Expression of selected Echinococcus granulosus antigens in Bacillus subtilis [month 24]

Work package 2

Host-Parasite Interaction and Vaccine Delivery

Objectives

• To identify differences in local early inflammatory immune responses after intramuscular immunisation with different adjuvants

• To assess the involvement of dendritic cell maturation and phenotype in the induction of protective immunity against O. ostertagi, F. hepatica and D. viviparus after intramuscular immunisation

• To assess the impact of glycan on the immune responses initiated by immunisation with H. contortus H11 and O. ostertagi OPA antigens

• To develop in vitro screening models to identify potentially protective adjuvants

• To define antibody binding to native and recombinant F. hepatica cathepsin L.

• To assess the immune responses to vaccination and correlations to protection

• To develop and apply these methodologies to define the contribution of glycan to protection using selected antigens

Description of work and role of partners

A major challenge in helminth vaccine development is the formulation of antigen delivery systems which induce the appropriate protective immune response. Antigens undergoing evaluation in ruminants have usually been delivered subcutaneously, intramuscularly or intra-peritoneally in association with an adjuvant, the latter being included to improve immunogenicity. The effect of the adjuvant has shown to be crucial for vaccine efficacy.

Furthermore, since many helminths, including those which are the targets of this proposal, have the capacity to modulate the immune response of the host to their own advantage, thus establishing chronic infections, it is necessary to understand the nature of the helminth-host immune reaction in order to deliver effective protection, and to inform the adjuvant/vaccine delivery schedule necessary.

In this workpackage we will explore the immunological events following immunisation of target hosts with candidate vaccines, investigate the mechanisms of protection elicited, and assess the contribution of helminth glycan moieties to protection/immunomodulation

• ELISA analysis of antibody, FACS and histological analyses of cellular responses will provide the routine tools for analysis of vaccine-induced immune responses. In this workpackage we will also evaluate methods to improve and sustain the protective responses.

• We will analyse differences in the initiation of the immune response after intramuscular injection of different adjuvants, which may be associated with the presence or absence of protection. DNA arrays can dissect the influences of antigen or adjuvant on vaccine performance. Early changes in gene transcription patterns in bovine muscle after vaccination with different adjuvants will be analysed by micro-array analysis of mRNA extracted from the injection sites.

• Potential differences in infiltration of different cell types at the injection sites will be investigated using histological methods.

• Activation and maturation of dendritic cells (DC) will be investigated using histology and FACS analysis. DC’s have the capability to polarise naive T helper cells towards a Th1 or Th2 phenotype. Differences in the initiation of the immune response in DCs will be analysed when exposed to antigen with Quil A, aluminium hydroxide or ISCOMs. Parallel studies will be undertaken in D. viviparus and F. hepatica. In the case of the latter, the impact of a Fasciola vaccination regime on the effectiveness of commonly used virus vaccines will be studied.

• Comparison of the responses in DCs when exposed to glysosylated or glycan disrupted antigen.

• We will investigate the nature of binding of antibodies induced by infection and those induced by vaccination to native purified vaccine targets.

• We will seek to define the mechanism of protection of rmCL vaccines against bovine fasciolosis and the impact of these responses on the efficacy of viral and bacterial vaccine.

• Epidemiological evidence for bystander immunosuppression in bovine fasciolosis will be sought, particularly in respect of economically/zoonotically important infections (salmonella, Johnes’ disease) for which cellular immunity is important.

• For Ostertagia L4 and Haemonchus gut antigen-based vaccines, the effector is known to be systemic IgG and work will focus on evaluating novel adjuvants e.g. ISCOMs for their ability to generate high and sustained IgG titres. Antibody avidity will also be assessed exploiting knowledge available in F. hepatica.

• The mucosal, liver and mesenteric lymph node immune responses of the dog to E. granulosus will be monitored during the first days post experimental infection

• For Echinococcus, attempts will be made to improve the levels of protection described earlier by antigen delivery using alternative living (Bacillus subtilis - biofilms) and non-living (nano-particle) delivery methods.

Description of deliverables

D2.1) The effectors: Refined definition of the precise immunological effectors of vaccine-induced immunity [month 42]

D2.2) Antibody and protection: The nature of antibody binding required to stimulate protection [month 18]

D2.3) Initiation of immune response with different adjuvants: To identify the optimal adjuvant to stimulate the desired protective immune response. Differences in the initiation of the immune response in DCs will be analysed when exposed to O ostertagi antigen with Quil A, aluminium hydroxide or ISCOMs. Parallel studies will be undertaken in D. viviparus and F. hepatica. In the case of the latter, the impact of a Fasciola vaccination regime on the effectiveness of commonly used virus vaccines will be studied. [month 12]

D2.4) Microarray definition – adjuvants, Oo: We will analyse differences in the initiation of the immune response after intramuscular injection of different adjuvants, which may be associated with the presence or absence of protection. DNA arrays can dissect the influences of antigen or adjuvant on vaccine performance. Early changes in gene transcription patterns in bovine muscle after vaccination with different adjuvants will be analysed by micro-array analysis of mRNA extracted from the injection sites. ply microarray analyses to define the recipient (cattle) response to a vaccine (O.ostertagia antigen) and how this changes with different adjuvants. [month 24]

D2.5) Provision of a rational base for adjuvant selection: Using data from deliverable 4, we will select the adjuvant(S) most likely to stimulate and enhance these responses [month 36]

D2.6) Development of spore and nanoparticle vehicles for antigne delivery: For Echinococcus, attempts will be made to improve the levels of protection already established with conventional adjuvants. Antigen delivery using alternative living (Bacillus subtilis - biofilms) and non-living (nano-particle) delivery methods will be evaluated. [month 24]

D2.7) F hepatica - host/parasite immune interactions: Protective immune responses to F hepatica [month 36] D2.8) fluke and inflammation: [month 36]

D2.9) Towards a T hydatigena vaccine: Studies with T. hydatigena to verify the impact of the most promising vaccine (B. subtilis or nanoparticle carrying a vaccine protein prototype on the reproductive organs of worms: to test the efficacy of the vaccine [month 36]

Workpage 3

Vaccine trials– housed and field efficacy testing

Objectives

• To continue the development of existing prototype recombinant protein vaccines against:- 1) O. ostertagi 2) D. viviparus 3) F. hepatica 4) E. granulosus by conducting housed vaccine trials to confirm and enhance efficacy

• Testing a recombinant L4 gut antigen vaccine against O. ostertagi

• To conduct a vaccine trial with recombinant versions of these antigens

• To evaluate the protective capacities of immunodominant Cooperia ES proteins in a vaccination experiment in cattle – towards a multivalent nematode vaccine for cattle

• To evaluate the protective efficacy of Haemonchus H11 expressed in C. elegans

• To conduct field trials with prototype recombinant protein vaccines against O. ostertagi, F. hepatica, D. viviparus and E. granulosus.

• To confirm the efficacy of the H. contortus native protein vaccine in goats and sheep in the tropics and to evaluate the utility of this approach against H. placei in cattle.

• To enhance and prolong vaccine-induced protection by evaluating different vaccine delivery vehicles where required

Description of work and role of partners

This is the most critical workpackage where the antigens described will be evaluated in vaccine trials to answer important questions such as :- 1) does the antigen stimulate protective immunity; 2) If so is the level of protection sufficient to move the antigen into the next phase of development as described in WP4; 3) if not, can it be can it be improved. For the purposes of continuity, the experiments are described here and more detail is provided in the Scientific methods section. Experimental animal licences will be obtained from the appropriate national authorities prior to the commencement of work, and all of the experiments will be as approved by ethical review at the partners’ institutions.

1. Vaccine against Ostertagia ostertagi

1) Evaluation of the protective capacities of the recombinant OPA proteins in a vaccination experiment in cattle. A vaccination trial will be designed to evaluate the protective properties of the combination of the 3 recombinants, mimicking the native OPA fraction. One group will receive ~100 μg of the native OPA fraction per immunization in combination with 750￿μg of QuilA adjuvant (positive control group), another will receive adjuvant alone(negative control group) and a thrid will be immunized with a cocktail of recombinant OPA, 17kDa and 20 kDa with QuilA. After challenge with infective L3 larvae (1,000 L3/day; 5 days/week), faecal egg outputs, final worm burdens, worm lengths and sex ratios will be determined.. If this antigen cocktail confers protection, the recombinant proteins will be tested separately in a second trial to identify which contribute to the protective effect

2) Based on the results from this trial and WP 2, different adjuvants will be tested in a vaccine trial. The potential of different adjuvants to improve the protective capacities of the OPA antigens will be compared with the “gold standard” Quil A.

3) Field trial Ten calves vaccinated three times intramuscularly with 100 μg native or recombinant Ostertagia OPA, 17kDa and/or 20 kDa in Quil A (or another adjuvant, based on the results of WP3, see above) and ten controls given adjuvant alone will be turned out on to contaminated pasture grazed by first season calves the previous year.

The pasture will be fenced into 10 similar plots each of which will contain two calves of the same treatment group. Faecal egg counts will be made weekly., herbage samples will be collected monthly for pasture larval counts and the calves’ weight gains will be compared. All calves will be killed for worm counts and serum pepsinogen levels will be determined. Depending on the results of the vaccine trial with immunodominant Cooperia antigens (WP3, see above), a native Cooperia ES protein fraction may be included in this field trial.

L4 gut antigen vaccine
1) Repeat and extend the result obtained with the native antigen fraction The previous vaccine trial will be repeated using narrower sub-fractions of the native antigen fraction with the aim of confirming the finding and further characterising the protective components. This will require large numbers of donor calves to provide the several grams of fourth stage larvae necessary to prepare these fractions. Five groups of 7 housed worm free calves will be immunised 3 times 3 weeks apart with QuilA alone (the challenge controls) or the native antigen fraction shown previously to be protective (positive controls) or 3 with subfractions of it. Blood samples will be obtained weekly for serology. All calves will be challenged with a single dose of 50,000 Ostertagia L3 one week after the final immunisation. Faecal egg counts will be made 3 times a week from day 18 post challenge and the animals will ne killed for worm counts 5 weeks after challenge
2) Recombinant L4 gut antigen trial A cocktail recombinant vaccine will be made to contain similar quantities of the individual proteins in the native antigen vaccine and QuilA. The design of the trial will follow the protocol just described but with 2 groups of 7 calves immunised with either the recombinant protein cocktail or with QuilA only.

Task 3b D. viviparus
The protective potential of recombinant paramyosin will be investigated in:-
1) Housed helminth-free calves (4-10 months of age) randomly divided into groups of 5. The positive control group will receive the Bovilis Dictol-lungworm vaccine according to the manufacturer’s instructions. All other animals will be immunized three times intramuscularly with three-week intervals. Two test groups, one for Pmy expressed in yeast, the other for Pmy expressed in baculovirus, will receive ~100 μg recombinant protein per immunization in combination with 750￿μg of QuilA. The negative control group will receive QuilA alone. Serum will be taken from the animals to track the antibody response by ELISA. After the final immunization the animals will be challenged with 2000 infective larvae on two consecutive days. Faecal larval counts will be made during patency and male and female worm counts, worm lengths and widths will be determined post mortem..
2) A field study will be performed in which calves will be vaccinated three times intramuscularly with 100 μg recombinant protein with QuilA as above. Immediately after the last immunisation, all calves will be turned out together on a pasture that has been grazed by lungworm positive cattle in previous years. Vaccinated and control calves will be grazed together to ensure that all calves are exposed to the same level of nematode challenge and that the individual calf is the experimental unit. Individual faecal larvae counts will be collected weekly from turnout and the calves’ weight gains will be determined monthly. Worm counts and worm measurements will be made after post mortem in October.

Task 3c Haemonchus
Trials will be conducted with the native vaccine:- 3c i) In sheep grazing infested pastures in a tropical environment Three groups of 15 weaned lambs will be immunised twice with either 10, 5 or 2μg of vaccine. They and 15 controls immunised with adjuvant alone will be turned out on to the same Haemonchus infected pasture when 6 months old. The animals will be monitored weekly for faecal egg counts and blood samples will be taken for assaying haematocrits and serum antibody concentrations. Animals with a packed cell volume less than 15 will be treated with anthelmintic and their data will be excluded from the results. However if more than six individuals in the control group are this anaemic then the whole of that group will be treated and its subsequent data will be included. Further vaccinations may be given to the vaccine groups as and when it is considered necessary for protection to be maintained. 3c ii) In goats grazing infested pasture The design of this trial will be exactly the same as the sheep trial referred to in 3c i) above 3c iii) In cattle grazing infested pasture Three groups of 10 calves will be immunised twice with either 10, 5 or 2ug of vaccine. When about 6 months old they and 10 controls immunised with adjuvant alone will be turned out on to the same contaminated pasture grazed previously by Haemonchus infected cattle. The animals will be monitored and treated exactly as described for the sheep and goat trials above.

Trials with recombinant H11 vaccine:- Two groups of 7 lambs (>3 months old) will be immunised with Quil A alone (controls) or with a combination of H11-1 and H11-4, expressed in C. elegans, with Quil A (vaccinates). Lambs will be immunised on 3 occasions 3 weeks apart and then, 2 weeks after final immunisation, given a single bolus challenge of 5,000 L3. Faecal egg output will be monitored from 15 days post infection until the end of the trial at 35 days post infection. Final worm burdens will be enumerated at necropsy. Blood samples, for antibody analyses by ELISA and haematocrit) will be taken at weekly intervals .

Task 3d Fasciola Animals selected for inclusion in vaccine trials will be free from liver fluke infection as determined by geographical location, serology and faecal examination. Blood for immunological and other analyses will be collected by jugular venepuncture. Experimental challenge infections will be carried out by administration of the required number of metacercariae within a gelatine bolus, using an anthelmintic dosing gun, as previously described. Faecal egg counts will be carried out by the sedimentation method, and counting of fluke burdens post-mortem by detailed dissection and examination of gall bladders, bile ducts and liver tissue, as previously described. Morphometric histopathological measurements developed by partner 10 (UCO) will also be used to assess protection. For field trials, animals will not be subjected to experimental infection but instead will be exposed to natural infection by being allowed to graze on known fluke-infected pastures. Cattle will be the target species for all trials.
3d i Experimental trial in Europe This trial, involving experimental challenge, will be used to select the optimum antigen for combination with rmFhCL1 for inclusion in subsequent field trials, and also to ensure that personnel from all sites involved in subsequent trials are trained in the standard operating procedures to be used for animal selection, data recording, post-mortem examination and immunological analyses in subsequent vaccine trials.
3d ii Field trial in Europe A trial using male, castrated, 3-6 month old Friesian calves will be carried out in Europe in Year 1 of the trial. This is the prime target cohort of a fasciolosis vaccine in this region. The trial sites will include Teagasc Research Farm, Athenry, Co. Galway, Ireland an area of high-fluke prevalence, together with two commercial farms in the same area. The trial will be conducted during the late summer/autumn, when numbers of metacercariae on pasture will be significant. Three groups of calves will be involved, Group 1 – Vaccinated with rmFhCL1 in oil adjuvant; Group 2- Vaccinated with rcmFhCL1 in combination with CL” and CL3; Group 3- Challenge control group A total of 60 animals will be included in each group, split evenly over the three sites.
3d iii Field Trial in South America This trial will replicate that of 3 d ii, but using 60 cattle in Peru

Task 3e E. granulosus

All work with dogs will be conducted following international guidelines on the use of animals for experimentation (recommendation of the European commission No L 358, ISSN 0378-6978). 3e I Preliminary study to define the immune response of dogs during the 12 first days post –infection. In Tunisia: 3 controls and 3 sets of 3 infected dogs will be killed at 4,8,12 days post infection respectively and samples of intestine, liver and mesenteric nodes will be collected for immunological studies by WP2.

Evaluation of vaccine prototypes: These trials will be undertaken in Morocco and Tunisia as before. Dogs will be of local breeds and, less than 5 months at the time of the vaccination to coincide with the timings of normal domestic dog vaccination. In each country, the vaccine prototypes, with living carrier or with nanoparticules, will be given twice orally to each of 7 dogs , 20 days apart. Living carrier alone and nanoparticules alone will be given to 7 controls. Five dogs will be used as challenge controls. A challenge infection with 75000 living protoscoleces from sheep origin will be given to all dogs 20 days after the last immunization. Two dogs without infection will be used as controls to ensure, that dogs had no access to cysts during the experiment of environment. For safety reasons all dogs will be killed 26-29 days post-challenge, before the appearance of eggs. Worms will be enumerated and measured and host tissues sampled for histological analyses. 3e ii Assessment of impact of intestinal immunity on the reproduction potential of the tapeworm Taenia hydatigena as a safe model. The impact of a potential vaccine candidate on tapeworm reproduction can be safely investigated with T. hydatigena which is not zoonotic This T. hydatigena animal model as well as methods to estimate the reproduction potential of the worm during patency is a fully established protocol at the Institute of Parasitology in Zurich. For this experimental model a T. hydatigena-derived experimental vaccine will be prepared as described above based on the CRISP gene product. The T. hydatigena orthologue of the CRISP

gene will be identified and used to construct the appropriate expression vectors. We will take into account the results of the vaccine carrier study: the most promising vaccine strategy will be applied here (in case that both strategies, living and non living carriers, should show equal potential, both could be tested. The vaccination study will be carried out at the experimental units of the Vetsuisse Faculty at the University of Zurich, Switzerland and will be conducted in accordance with international guidelines on the use of animals for experimentation (recommendation of the European commission No L 358, ISSN 0378-6978) after approval by the Veterinary Office of the Canton Zurich.

Experimental design: Group1) negative control group of cestode free dogs- Group 2) dogs previously exposed for 4 month to an intestinal T. hydatigena infection (positive controls) -Groups* 3a and b) control dogs immunised with living carrier or with nanoparticules without the antigen-Group 4a and b) vaccine groups (with living carrier and/or with nanoparticules )*.

Task 3f Cooperia A vaccination trial will be performed to evaluate the protective properties of immunodominant Cooperia ES proteins, identified in WP1. A Holstein cross-bred population of helminth-free calves (7-10 months of age) will be randomly divided in groups of 7 animals. All animals will be immunized three times intramuscularly with a three-week interval. One to three groups will receive ~100 mg of a purified immunodominant ES protein fraction per immunization in combination with 750 mg of QuilA adjuvant. One group will receive the same amount of QuilA alone (negative control group). Serum will be taken from each animal before the first immunization and one week after the second immunization. After the final immunization the animals will be challenged with a trickle infection of 25,000 infective C. oncophora L3 larvae (1,000 L3/day; 5 days/week). Standard parasitological parameters (i.e. FECs, worm counts and worm lengths) will be analysed to assess the level of protection against infection.

Description of deliverables

D3.1) Prototype O. ostertagi vaccine comprising either single or combinations of the 3 recombinant OPA pro: A vaccination trial will be designed to evaluate the protective properties of the combination of the 3 recombinants, mimicking the native OPA fraction. [month 30]

D3.2) Prototype O. ostertagi L4 gut antigen vaccine: Evaluation of proteins purified from the intestine of L4 parasites as a vaccine against O Ostertagi in cattle [month 36]

D3.3) Prototype C. oncophora vaccine comprising purified native ES proteins: Adult ES material will be harvested in vitro and whole ES or fractions tested as a vaccine against homologous infection in cattle [month 36]

D3.4) Haemonchus native adult gut protein vaccine: Continued development of an effective H contortus vaccine based on native parasite proteins [month 36]

D3.5) Proof of principle of the utility of C. elegans for the production of efficacious nematodes protein: H contortus antigens with known protective efficacy as native proteins will be expressed in C. elegans and vaccine efficacy measured [month 30]

D3.6) Improved recombinant cathepsin L-based vaccines for the control of F. hepatica infection in cattle: Work will focus on improving the efficacy of recombinant cathepsin L vaccines [month 33]

D3.7) A prototype recombinant vaccine for the control of bovine lungworm infection: Indiidual recombinant proteins or combination thereof will be tested as vaccines against lungworm in cattle [month 36]

D3.8) An orally-delivered recombinant vaccine for the control of E. granulosus in dogs: Evaluation of differing recombinant proteins as vaccines to reduce infection in dogs [month 36]

Work package 4

Business Planning, Epidemiological Modeling and Pilot Manufacturing

Objectives

• To define acceptable levels of efficacy for a new vaccine(s) by using epidemiological and economic modelling resulting in a cost-benefit analysis acceptable to the commercial partner and relevant regulatory authorities.

• Use a high-level generic business/development plan to progress targeted research with a lead antigen(s) from lead seeking to proof of concept.

Description of work and role of partners

Modelling vaccine efficacy: Models will be developed for Fasciola hepatica and Haemonchus contortus in the first instance to assess the following: Mathematical models for F. hepatica will be developed to assess the following:

1. The efficacy of vaccination and duration of protection required to reduce (a) disease and (b) transmission within a flock or herd.

2. A cost-benefit analysis of the implementation of a vaccine programme relative to use of chemotherapy, incorporating the risk of development of anthelmintic resistance. Successful application of vaccines can be affected by many factors and mathematical models are widely used to appraise the usefulness and cost-effectiveness of a vaccine prior to its introduction. Using such an approach it is possible to model how the effectiveness and coverage of a proposed vaccine might affect the transmission coefficient within a population. It is also possible to consider how the benefits afforded by a vaccine will vary over time, given changing prevalences of infection driven by future environmental change. For the purposes of this study, a population of animals in a single farm unit will be considered and a transmission co-efficient calculated to describe the spread of infection. A suitable modelling framework which describes the spread of nematodes within human populations has been developed for roundworms and more recently, for hookworms); the latter is a stochastic model incorporating important epidemiological heterogeneities including worm aggregation ('overdispersion') and host differences in susceptibility. Similar models will be developed for the first time for liver fluke.

The development of models for helminth parasites is complicated by several factors including: the slow development of immunity, which may be affected by the immunomodulation induced by the presence of the parasite itself; the complexity of transmission and in particular the involvement of the snail intermediate host; the magnitude and longevity of infection which determines the level of egg output and hence contamination of pasture and finally the number of hosts within a population that are infected (for many helminth parasites there is an overdispersion of infection with a small number of animals harbouring large infections and a large number of animals within the population harbouring light or no infection). Compared to nematodes, for fluke there is a relative paucity of data on the distribution of parasites within a population and the factors that affect the distribution.

For this reason we propose gathering quantitative data from the field, using the 20 farms recruited for the immunology studies will be used to inform model development and parameterisation. Specifically we will measure re-infection rates, profiles (intensity) of worm burdens within populations which may be affected by exposure, genetic heterogeneity of the susceptible host population and distribution of parasite burdens between hosts (most parasites show a negative binomial distribution and some hosts are predisposed to heavy or light infections). Parasite mediated immunosuppression may affect vaccine performance, thus it may be necessary to treat animals that have been exposed to infection, prior to vaccination.

Rates of parasite transmission are likely to change in future, given environmental and climate change, because several stages of the liver fluke life cycle (free-living and within the snail intermediate host) are sensitive to temperature and moisture. A different rate of transmission in the future will affect the relative benefits afforded by vaccination. A climate-driven model of the basic reproduction number (R0) of fluke, developed by Partner 9 (van Dijk et al, in prep), allows this to be investigated in space and time. The modelling framework described above includes a constant term for the R0 of nematodes; here, we will drive the model using a time- and space-varying estimate of the R0 of fluke.

Business/Development plan: This plan will be activated at the stage that a lead antigen from any of the parasites is deemed close to moving from the category of lead seeking to proof of concept. The plan will be initiated on completion of the following: (i) demonstration of target efficacy and safety in the parasite’s natural host and (ii) assessment that the of technology to a suitable pilot manufacturing facility together with confirmation of efficacy and chosen expression system produces adequate yields of the antigen, is commercially viable or can deliver public good subject to charitable funding and thus suitable for scale-up manufacture. Scale-up and transfer safety of the lead antigen(s) are considered essential criteria for meeting proof of concept. Aspects of this plan are outlined in more detail in the proposal section outlining dissemination activities.

Description of deliverables

D4.1) Information on basic host-parasite interactions in naturally infected cattle: Successful application of vaccines can be affected by many factors and mathematical models are widely used to appraise the usefulness and cost-effectiveness of a vaccine prior to its introduction. This work will collate the available information [month 24]

D4.2) Predictive Model development: Model to describe the efficacy of a vaccine and duration of protection required to reduce (a) disease and (b) transmission within a herd. [month 36]

D4.3) Cost benefit analysis of vaccine against fluke: Defining the commercial boundaries for a vaccine [month 36]

D4.4) Fluke vaccine efficacy in the field: Does the prototype fluke vaccine work under field conditions? [month 36]

Work package 5

Project management

Objectives

Ensuring the timely and successful completion of the project activities

Description of work and role of partners

The project is centred around four core helminth groups interconnected by major shared scientific disciplines, and a common plan for training and demonstration activities. These activities are described in detail in Section 2.1 Management structure and procedures. Briefly, The administration office will be embedded in the Moredun Research Institute’s administration structure. This office will administer the project on a day to day basis and ensure that the actions noted below are undertaken on schedule. This office will have particular responsibility for the financial management of the project..

A management board, comprising the 4 helminth group sub-cordinators and 5 workpackage managers, will meet formally every 6 months from the start of the project and will review progress against the Milestones and Deliverables with the aid of written progress reports. The management board will have particular responsibility for addressing areas where progress is behind schedule, The management board will also interact with the commercial partner to ensure progression of lead vaccine candidates into business development outline in WP4. They will be aided in these activities by a scientific advisory panel, composed of independent experts in the field, who will be invited to provide independent comment on progress and project integration. The Board and panel will oversee Project integration and reporting and ensure timely submission to the European Commission of a full progress report at months 18, 36 and 48 (Final report). Progress towards completing milestones on the path to each deliverable will provide the major tool for project management. Management reports will be prepared

by the co-ordinator every 6 months and will be presented to the Management Board and Scientific advisory board. Activity and Management reports will address all items stated in the guidelines for FP7 Cooperation projects. The consortium recognises the communication between participants in geographically remote locations is essential for delivery of the project objectives. Day to day communication will be maintained by email. Sub group and workpackage integration will be enhanced by the use of video and teleconference facilities.

Description of deliverables

D5.1) Progression of the project: To ensure progression of the project as indicated in the GANTT chart outlining milestone progression during the lifetime of the project. [month 48]

D5.2) Training: Execution of training plans [month 48]

D5.3) Web site: Development and maintenance of project web-site [month 48]

 

 


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