[The role of gamma delta T cells in infectious disease].

There have been several lines of evidence that at least significant fraction of gamma delta--T cells are specialized to recognize epitopes on mycobacterial antigens including 65 KD heat shock protein(HSP). Since HSP is known to be highly conserved in amino acid sequences from prokaryotes to eukaryotes, it is possible that the HSP--specific gamma delta--T cells may recognize the endogenous HSP expressed by autologous cells. The broad--reactive gamma delta--T cells may be responsible for protection during the period between an early stage covered mainly by phagocytes and a late stage covered by typical immunities in terms of the time sequence after microbial invasions.