Mice Deficient in Perforin, CD4 + T Cells, or CD28-Mediated Signaling Maintain the Typical Immunodominance Hierarchies of CD8 + T-Cell Responses to Influenza Virus

Abstract

ABSTRACT CD8 T-cell (T CD8+ ) responses elicited by viral infection demonstrate the phenomenon of immunodominance: the numbers of T CD8+ responding to different viral peptides vary over a wide range in a reproducible manner for individuals with the same major histocompatibility complex class I alleles. To better understand immunodominance, we examined T CD8+ responses to multiple defined viral peptides following infection of mice with influenza virus. The immunodominance hierarchy of influenza virus-specific T CD8+ was not greatly perturbed by the absence of either perforin or T-helper cells or by interference with B7 (CD80)-mediated signaling. These findings indicate that costimulation by antigen-presenting cells (APCs) or killing of APCs by T CD8+ plays only a minor role in establishing the immunodominance hierarchy of antiviral T CD8+ in this system. This points to intrinsic features of the T CD8+ repertoire as major contributors to immunodominance.