RABIES GLYCOPROTEIN

THE PURPOSE OF THIS AMENDMENT IS TO CORRECT THE ESTIMATED MAGNITUDE OF THE PROJECT TO BETWEEN $50,000 AND $100,000. ALL OTHER TERMS AND CONDITIONS REMAIN THE SAME. USDA, APHIS, National Veterinary Science Lab (NVSL), Ames, Iowa,has a requirement for Gene synthesis, cloning, expression and production of 50mg each of the Recombinant Rabies Virus Glycoprotein (RVG) and its variants and p75 receptor in Expression Cells. We are seeking interested sources from small-business concerns that are capable of providing the following work: Background: Rabies glycoprotein G (gpG) is a protein found on the surface of the rabies virus which attaches to a receptor on the host cell, the p75 neurotrophin receptor (p75NTR). The two forms of gpG are a single gpG unit (monomeric gpG), and a trimeric form composed of three units (trimeric gpG). Monomeric gpG is secreted by infected cells and is not present in the rabies virus itself. Trimeric gpG is formed during the assembly of the virus surface membrane, and is the only form that attaches to p75NTR. The gpG is shaped differently depending on whether in the monomeric or trimeric form. Only the trimeric form of gpG attaches to p75NTR, and only anti-trimeric gpG antibodies neutralize the rabies virus. The monoclonal antibody (mAb) used to develop an ELISA based potency assay to replace the current NIH test should only react with the trimeric form of gpG. Both monomeric and trimeric gpG are necessary as reagents in characterization of the mAbs. Using a cell expression system and cloning only the ectodomain of the rabies gpG also has the following advantages: eliminates the need to work directly with live rabies virus and the associated BSL safety requirements, quickly produces large quantities of specific gpG and P75NTR proteins and allows for production of reagents to characterize mAbs. Deliverables: The following 5 constructs were chosen for cloning, expression and purification: • Rabies gpG ectodomain • Rabies gpG ectodomain + His6x tag • Rabies gpG ectodomain + fibritin foldon • Rabies gpG ectodomain + fibritin foldon + His6x tag. • P75 Neurotrophin Receptor The His6x tag is important because it facilitates a more efficient purification method to increase yield and decrease cost of production. The proteins will need to be compared to non-His6x tagged versions to ensure the tag does not interfere with expression/secretion or the native conformation. The fibritin foldon has been shown in studies to lead to the stable trimerization of rabies gpG that would normally occur when the protein is bound in the virus membrane. The estimated magnitude for this project is between $50,000 and $100,000. The North American Industry Classification System (NAICS) code is 621511 with a small business size standard of $30M. This is not a request for proposals, but instead market research to determine interested small-business concerns prior to issuing a solicitation. A determination by the Government on the method of competing this requirement has not been established. The Government will not award a contract based on this Sources Sought Notice or the information received, nor will it reimburse participants for the information they provide. If you are an interested small-business concern, please provide the following information: 1) Small business name and point of contact; 2) DUNS number and CAGE code; 3) Evidence of small-business concern status; and 4). A brief Statement of Capability (no more than three pages) which demonstrates the ability to meet the specialized work requirements above. Include any past performance information on contracts of similar size and scope, and indicate the degree of work self-performed. Also include past performance references with names and phone numbers. Electronic responses are preferred. Information provided will not be used as a part of any subsequent solicitation requirement. Interested sources who submit data are responsible for appropriately marking information if it is proprietary in nature. A determination by the Government not to compete this proposed contract action based on this notice is solely within the discretion of the Government. Responses are due no later than 2:00 p.m., Central Standard Time, on August 19, 2014 to the attention of Joanne Mann, Contracting Officer, via e-mail to [email protected] or by fax to 612-336-3554.