? The long-term objectives are to develop an enzyme-linked immunoassay (ELISA) for Severe Acute Respiratory Syndrome (SARS), based on synthetic peptide antigens. The test will be stable and free of biohazardous manufacturing operations and components, and is intended as a safe and rapid method for serological surveillance. The test will be amenable to large scale manufacture and compatible with fully automated diagnostic screening.
Specific aims are 1) to identify and optimize the peptide antigens, including antigens from non-structural SARS coronavirus (SCoV) proteins, in addition to peptides from structural proteins S, M, and N that have already been identified; 2) formulate a SARS ELISA test kit optimized for sensitivity and specificity; 3) validate the kit with a panel of characterized sera from SARS patients and various panels from the sera of subjects that have not been exposed to the SCoV; 4) perform a large-scale clinical trial at multiple sites in the US, Taiwan and China; 4) accomplish the commercial scale production of kits; and 5) submit a PMA or PDP application for US and foreign regulatory approvals. A prototype SARS ELISA having peptide antigens from the S, M, and N structural proteins of SCoV is to be improved by the addition of non-structural peptides whose sequences are deduced from the putative pol region of the SCoV genome. Overlapping peptides will be synthesized to cover the entire pol la and lb open reading frames. Peptides will be of lengths from 20-60 amino acids. Individual peptides will be screened by the ELISA method for reactivity to a collection of sera from confirmed SARS patients. Serologically reactive epitopes on the peptides will be refined for optimum sequences and conformation. The newly identified non-structural peptide antigens will be added to the solid-phase antigen formulation of the SARS ELISA. The peptides and kits will be manufactured and characterized with cGMP standards. Large-scale clinical trials will be done at facilities in Asia on extensive collections of SARS positive sera. ? ?
