Both L3T4+ and Lyt-2+ helper T cells initiate cytotoxic T lymphocyte responses against allogenic major histocompatibility antigens but not against trinitrophenyl-modified self.
This study characterizes the T helper (Th) cells that initiate primary cytotoxic T lymphocyte (CTL) responses against allogeneic and trinitrophenyl (TNP)-modified self class I major histocompatibility (MHC) determinants. We show that two distinct Th cell subsets participate in allospecific CTL responses: (a) an L3T4+,Lyt-2- class II-restricted Th cell population, and (b) an L3T4-,Lyt-2+ class I-restricted Th cell population. Both of these T cell subpopulations were shown to function in allospecific CTL responses as helper cells by their ability to show synergy with allospecific CTL precursors. Thus, primary class I allospecific CTL responses represent an immune response involving not only L3T4+ Th cells, but Lyt-2+ Th cells as well. One of the necessary functions performed by both L3T4+ and Lyt-2+ Th cell populations in allospecific CTL responses was found to be the secretion of interleukin 2. Finally, despite the many similarities between anti-allo- and anti-TNP-CTL responses, anti-TNP-CTL responses were found to be mediated by only L3T4+ Th cells, not by Lyt-2+ Th cells. Consequently, Lyt-2+ Th cells appear to be a helper cell population that is primarily involved in MHC-specific immune responses.
Mizuochi
T
T
Golding
H
H
Rosenberg
A S
AS
Glimcher
L H
LH
Malek
T R
TR
Singer
A
A
D000818:Animals; D000950:Antigens, Ly / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D006183:H-2 Antigens / Q000276:immunology; D006649:Histocompatibility Antigens / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007376:Interleukin-2 / Q000096:biosynthesis; D007519:Isoantigens / Q000276:immunology; D051379:Mice; D011828:Radiation Chimera; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014301:Trinitrobenzenes / Q000276:immunology
D000950:Antigens, Ly; D006183:H-2 Antigens; D006649:Histocompatibility Antigens; D000949:Histocompatibility Antigens Class II; D007376:Interleukin-2; D007519:Isoantigens; D014301:Trinitrobenzenes