Search

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve and recently emerging variants with substitutions in the Spike protein have led to growing concerns over increased transmissibility and decreased vaccine coverage due to immune evasion. Here, sera from recipients of a single dose of our Ad26.COV2.S COVID-19 vaccine were tested for neutralizing activity against several SARS-CoV-2 variants of concern. All tested variants demonstrated susceptibility to Ad26.COV2.S-induced serum neutralization albeit mainly reduced as compared to the B.1 strain. Most pronounced reduction was observed for the B.1.351 (Beta; 3.6-fold) and P.1 (Gamma; 3.4-fold) variants that contain similar mutations in the receptor-binding domain (RBD) while only a 1.6-fold reduction was observed for the widely spreading B.1.617.2 (Delta) variant.

TheVALITEST technical periodic report M1-M18 details the work carried out by the partners and overviews the progress of the tasks as described in the Description of Actions (DoA) during the first reporting period M1-M18 (May 2018-October 2019).

A list of general minimum criteria was developed to be used in preparation of reference materials to be used in interlaboratory testing, including validations through test performance studies. The list was based on previously identified criteria in standards including ISO standards, EPPO guidelines, deliverables of relevant projects, related fields, and own experience of project partners. Several additional criteria were proposed: ‘availability’, ‘purity’ and ‘commutability’. These criteria result from a series of discussions, taking into account previous work and relevant international standards. Where relevant, each criterion was first defined as a series of levels from the highest to lowest ranking with the lowest ranking considered to be the minimum. Depending on the intended use, the reference material may need to fulfil higher levels of selected criteria or some criteria may not be relevant at all. The criteria were tested by the organizers of the TPS in round 1 of validation within VALITEST project which include bacteria, viruses, nematodes and fungi. The systematic and structured approach of describing RMs was found to be useful in promoting transparent descriptions of the RMs used and comparability of TPSs, as well as a step toward implementing FAIR data principles. The criteria defined here are applicable, potentially with minor modification, beyond the scope of this deliverable and project to other pests and other uses of RMs. A list of general minimum criteria was developed to be used in preparation of reference materials to be used in interlaboratory testing, including validations through test performance studies. The list was based on previously identified criteria in standards including ISO standards, EPPO guidelines, deliverables of relevant projects, related fields, and own experience of project partners. Several additional criteria were proposed: ‘availability’, ‘purity’ and ‘commutability’. These criteria result from a series of discussions, taking into account previous work and relevant international standards. Where relevant, each criterion was first defined as a series of levels from the highest to lowest ranking with the lowest ranking considered to be the minimum. Depending on the intended use, the reference material may need to fulfil higher levels of selected criteria or some criteria may not be relevant at all. The criteria were tested by the organizers of the TPS in round 1 of validation within VALITEST project which include bacteria, viruses, nematodes and fungi. The systematic and structured approach of describing RMs was found to be useful in promoting transparent descriptions of the RMs used and comparability of TPSs, as well as a step toward implementing FAIR data principles. The criteria defined here are applicable, potentially with minor modification, beyond the scope of this deliverable and project to other pests and other uses of RMs.

A general standard operating procedure (SOP) for the production of reference material (RM) for use in plant health diagnostics was developed within the VALITEST project. The general SOP was designed based on information on existing SOPs and guidelines available with the consortium partners (Deliverable 3.2) and partly incorporates the quality criteria for reference material (Deliverable 3.1). The general SOP describes the different steps required in the production process, ranging from the different possible sources of the reference material, tests to confirm its identity, possibly required multiplication steps to the actual production process. For each step in the process, criteria and critical points can be identified, but they will depend on the nature of the RM and on the target test in which the RM will be used. The original Deliverable 3.2 (February 2019) was evaluated by all partners (Milestone 3.4 Evaluation report) and updated towards this new version. The updated general standard operating procedure (SOP) for the production of reference material (RM) includes a stand-alone version of a template for the production of RM (Annex I) and an example of a full SOP for the production of RM of Fusarium circinatum to be used in (Real-Time) PCR assays (Annex II).

A general standard operating procedure (SOP) for the production of reference material (RM) for use in plant health diagnostics was developed. The general SOP was designed based on (limited) information on existing SOPs and guidelines available with the consortium partners. The general SOP describes the different steps required in the production process, ranging from the different possible sources of the reference material, tests to confirm its identity, possibly required multiplication steps to the actual production process. For each step in the process, criteria and critical points are identified. The criteria that reference material has to meet, and their minimum required levels as identified and described in Deliverable 3.1 of WP3 form an import basis of the final production process.

Pepino mosaic virus (PepMV) has caused great concern in the greenhouse tomato industry after it was found causing a new disease in tomato in 1999. The objective of this paper is to investigate alternative hosts and compare important biological characteristics of the three PepMV strains occurring in Europe whentested under different environmental conditions. To this end we compared the infectivity and symptom Development of three, well characterized isolates belonging to three different PepMV strains, EU-tom, Ch2 and US1, by inoculating them on tomato, possible alternative host plants in the family Solanaceae and selected test plants. The inoculation experiments were done in 10 countriesfrom south to north in Europe. The importance of alternative hosts among the solanaceous crops and the usefulness of test plants in the biological characterization of PepMV isolates are discussed. Our data for the three strains tested at 10 different European locations with both international and local cultivars showed that eggplant is an alternative host of PepMV. Sweet pepper is not an important host of PepMV, but potato can be infected when the right isolate is matched with a specific cultivar. Nicotiana occidentalis 37B is a useful indicator plant for PepMV studies, since it reacts with a different symptomatology to each one of the PepMV strains.

The performance of a kite power system depends for a large part on the performance of the kite. In a pumping system the glide ratio, the maximum allowable wing loading and the ability to power and depower can significantly affect the average input power to the generator. This poster gives an overview of research activities and results in the field of kites at the TU Delft institute ASSET.