Characterization of human T cell clones specific for coronavirus 229E

Coronaviruses (CV) are pleomorphic enveloped RNA viruses that are ubiquitous in nature, causing a variety of diseases in both man and domestic animals. In man, CV are generally associated with upper respiratory tract infections. The two prototype strains that are the best studied human CV isolates and which are thought to be responsible for most of the respiratory infections caused by CV are called 229E and OC43. Humoral responses consisting of neutralizing antibodies to CV are present in most individuals by six years of age. Although the cellular immune response to CV in man has not been characterized at all, it is known that the spike (S) and nucleocapsid (N) proteins elicit the major cell mediated immune responses in the mouse. This report describes the production and characterization of eleven independently isolated T cell clones that are specific for the human CV(HCV) 229E. The T cell clones are CD4+ and presumably recognize a processed viral peptide presented by class II molecules on the surface of antigen presenting cells. Of six 229E-specific T cell clones tested against purified viral proteins, three recognize the 180 kD spike glycoprotein while the other three recognize the 55 kD nucleocapsid phosphoprotein. Analysis of the human T cell mediated response to HCV will provide information regarding which viral proteins elicit the immunodominant response, what the fine specificity of these T cell clones are (immuno-dominant peptides), and what the T cell receptor (TCR) and cytokine usage is of these virus specific clones.