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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
185:103-125&s_comma; 2002.

世話人:山本 雅、○高津聖志(5449-5260)