Dr. Rolf Zinkernagel 博士特別講演会のお知らせ
開催日時：平成15年 ６月 ９日（ 月 ） １１：００～１２：４５
講師：Prof. Rolf M. Zinkernagel
所属：Institute for Experimental Immunology
University of Zurich、Switzerland
演題：Immunological memory and vaccines
概要：Resistance of vertebrate hosts against infections comprises important natural or innate immunity combined with adaptive immune responses of T and B cells. Viruses&s_comma; bacteria or classical parasites all probe the limit of
immune responses and of immunity. They offer therefore an excellent opportunity to assess the biology&s_comma; physiology and molecular aspects of
immune responses and help to characterize the three basic parameters of immunology e.g. specificity&s_comma; tolerance and memory. Various experiments will be summarized that indicate that the rules of anti-viral&s_comma; anti-tumor&s_comma;
anti-organgraft and of autoimmune responses are basically the same.
Specificity: the specificity repertoire of T and B cells is probably in theorder of 103 - 105 specificities expressed by T cells&s_comma; or by neutralizing antibodies. Tolerance is best defined by rules of reactivity to eliminate
infections while avoiding destruction of normal cells by complete elimination of T cells that are specific for antigens persisting within the
blood and lymphatic (lymphohemopoietic) system. Induction of a T cell response is the result of antigens newly entering lymph-nodes or spleen&s_comma;
initially in a local fashion and exhibiting an optimal distribution kinetics within the lymphohemopoietic system. Antigen staying outside of lymphatic tissues are mmunologically ignored (e.g. are nonevents). Memory is the fact that a host is resistant against disease caused by re-infection with the same agent. Memory correlates best with antigen-dependent maintenance of high antibody titers in serum and mucosal secretions&s_comma; or with an antigen-driven activation of T cells&s_comma; such that they are protective
immediately against peripheral reinfections in solid tissues. While antibodies transferred from mother to offspring are a prerequisite for the survival of otherwise unprotected immuno-incompetent offsprings&s_comma; activated memory T cells cannot be transmitted. Thus&s_comma; attenuation of infections in newborns and babies by maternal antibodies is the physiological correlate of man-made vaccines. T cells play an essential role in maintaining T help-dependent memory antibody titers&s_comma; but also in controlling the many infections that persist in a host at rather low levels (including tuberculosis&s_comma; measles&s_comma; HIV). Thus immune reactivity is regulated by antigen dose&s_comma; time and relative distribution kinetics.
Zinkernagel&s_comma; R.M. N.Engl.J.Med. 345:1331-1335&s_comma; 2001.
Zinkernagel&s_comma; R.M. Curr.Opin.Immunol 14:523-536&s_comma; 2002; Immunol Rev