[note attributions changed]
David Peritt (Peritt_d at a1.mscf.upenn.edu) wrote:
: someone wrote:
: >> (1) At what point does a CD4+ cell commit to a TH1 vs. a TH2
: >> response? Does it "commit," or is the process reversible?
: This topic was dealt with in various workshops at the recent congress. I
: think Anne O'Garra put it best. The commitment starts very early but is
: reversible until the cell is activated several times in the proper LK
: milieu then it becomes fixed. This explains why some investigators can
: switch an existing response. The switch is usually an outgrowth of
: previously unstimulated cells. Since most mouse people work at the
: polyclonal/bulk level. Us humanists who use clones do not see switching
: in established clones. The LK must be there early but commitment may
: take some time to fully reach permanance.
Are you saying that you don't believe in a Th0 response that can be
swayed one way or the other depending upon the fine specificity of
the antigen presented by MHC class II?
Are you familiar with Vipin Kumar's (UCLA) work with MBP ac1-9-specific
mouse clones? When lys4 -> met4, th1 *pheontype* -> th2?
My other comment is that I am surprised to hear that most mouse
people work at the polyclonal/bulk level. How would you test
in vitro clonal anergy and in vitro clonal deletion apoptosis
at polyclonal levels?
TKendrick
