Vg. Brichard et al., INDIVIDUAL-DIFFERENCES IN THE ORIENTATION OF THE CYTOLYTIC T-CELL RESPONSE AGAINST MOUSE-TUMOR P815, European Journal of Immunology, 25(3), 1995, pp. 664-671
We reported previously that the mouse tumor P815 expresses four distin
ct antigens (A, B, C, D) recognized by syngeneic cytolytic T lymphocyt
es (CTL). A fifth P815 antigen (E) was identified by means of a CTL do
ne derived from tumor-infiltrating lymphocytes. We compared a number o
f mice for the orientation of their CTL response with respect to the v
arious P815 antigens. Lymphocytes from mice inoculated subcutaneously
with living P815 cells were stimulated in vitro with tumor cells and t
he resulting CTL were tested against targets expressing either antigen
s A and B or antigens C, D and E. Many mice had an asymmetrical respon
se, some producing CTL directed almost exclusively against antigens A,
B and others producing CTL directed almost exclusively against C, D.
E. When mice were inoculated into two separate sites, different orient
ations in the responses of the two local lymph nodes were often observ
ed, suggesting that individual differences in the orientation of the a
nti-P815 CTL response do not result from preexisting differences betwe
en the animals. Asymmetrical CTL responses persisted in mice that were
given a second injection of tumor cells. A possible interpretation of
our results is that the major component of the CTL response is made o
f the progeny of a very small number of CTL precursors that happen to
be the first to be stimulated by the tumor antigens.