Cytotoxic T lymphocytes induced in mice by inactivated influenza virus vaccine

Abstract

THERE is abundant evidence that T cell-mediated lysis of virus-infected target cells generally requires H–2K or H–2D region histocompatibility between cytotoxic T lymphocytes (CTL) and target cells^1–6. The biological basis of this requirement is still uncertain. Studies using chimaeric mice suggest that T lymphocytes are selectively sensitised by the viral and H–2 antigens expressed on the infected cell and that killing only occurs when the target cell shares H–2K or H–2D identity with the immunising virus-infected cell⁷. It is important to determine whether virus infection of the host tissue is, in fact, necessary for specific CTL immunity to develop. If this were so, the use of inactivated virus or purified viral antigens would not be suitable as vaccines against diseases in which CTL were required to afford optimal protection. We report here that inactivated influenza virus vaccines are, in fact, quite capable of evoking haemagglutinin specific CTL.