Added: Jul 19, 2011 2:17 pm
The Centers for Disease Control and Prevention intends to issue a sole source purchase order to Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037-1000, for purchase of influenza glycan microarrays.
BACKGROUND: The viruses that caused the three most recent influenza pandemics were characterized by the incorporation of a hemagglutinin (HA) gene of animal origin. Avian influenza HAs bind preferentially to terminal sialic acids linked in 2-3 configuration to galactose in the glycans of the target cell plasma membrane. In contrast, human influenza HAs bind preferentially to 2-6 sialoside receptors. The available evidence suggests that a switch in the specificity of the HA is required for efficient infection and transmission in human hosts, as observed in a pandemic. Therefore, knowledge of the sialic acid structure specificity of potentially pandemic viruses is critically important for risk assessment and pandemic preparedness. Because there is insufficient knowledge to predict the sialic acid binding specificity of the HA by analysis of the amino acid sequence, the receptor binding specificity of viruses has to be analyzed by direct binding assays. The Centers for Disease Control and Prevention (CDC) has been utilizing glycan array technology (1,2) to analyze a large number of viruses to determine the binding specificity to ~100 sialoside structures using a simplified laboratory protocol. This technology allows characterization of emerging and potentially pandemic influenza viruses. Changes in receptor specificity will be monitored and correlated with mutations in the receptor binding site to aid in risk assessment for pandemic preparedness.
PURPOSE OF ACQUISITION: Acquire a supply of glycan array reagents to analyze influenza viruses from animals.
SCOPE OF WORK: The contractor will provide all labor, materials, and equipment required to supply CDC with glycan arrays as described in the technical requirements. The contractor should provide quality control data for the product as described in the technical requirements.
TASKS TO BE PERFORMED: Produce and deliver 450 glycan microarray slides that include a minimum of 100 unique sialoside structures that are representative of the major glycan structures present in humans and animals, including polylactosamine N-glycan structures. The micorarrays should have a shelf life of at least 2 years. The slides will be printed on glass slides such that a maximum of 2 virus samples will be analyzed per slide. Microscope glass slides with covalently attached glycans in a microarray format. The slides should be generated by covalent attachment of glycans containing a terminal amine that form an amide bond with the NHS derivatized silica. Microarrays should be printed using 0.6 nL of two concentrations of each glycan (100 nM), and each concentration printed in a replicate of six. A minimum of 100 unique glycans should be imprinted on the array, 30 possessing sialic acids with a2-3 linkages, 14 will have a2-6 linkages and six have a2-8 linkages; ~44 glycans that will represent the corresponding asialo structures, and ~20 will comprise model glycoproteins and polylactosamine N-glycan structures. Intra-lot slide-to-slide variability of the binding results from the printed array slides tested with several concentrations of a standard mixture of fluorescent lectins should not exceed 10%. Inter-lot variability will not exceed 15%. Array slides will be provided packaged in sets of 10 in desiccated airtight bags at room temperature and will have a shelf life of not less than 2 years.
PERIOD OF PERFORMANCE: 90 days from award of contract.
DELIVERABLES: (1) Deliver 450 glycan arrays that meet the specifications described in section IV. (2) Delivery report including the quality control information for each print/production batch of the supplied glycan arrays and a list of all the raw materials used for the production of the glycan arrays. The total supply of glycan arrays should be produced in a maximum of 5 batches.
MINIMUM VENDOR QUALIFICATIONS: (1) Vendor must be the actual manufacturer of the glycan arrays; (2) Vendor must have record of experience manufacturing sialoglycan ligand mictroarrays; and (3) Vendor must have record that glycan arrays previously manufactured at their facility yield consistently reliable receptor binding profile data with influenza viruses.
CDC believes that this requirement is met by only one provider. This procurement will be processed under the authority of FAR 13.106-1(b)(1). Only one responsible source and no other sources will satisfy agency requirements. No solicitation other than this is being issued. Interested persons are free to identify their interest and capability to respond to this requirement. This procurement is not set-aside for small business. For contractual questions contact Linda M. Young.