Macrophages as stimulators of MART-1 27-35 epitope-specific human cytolytic T lymphocytes in vitro.
BACKGROUND
Activation and expansion of antigen-specific cytolytic T lymphocytes (CTL) require epitope presented by antigen-presenting cells (APC). Presently, dendritic cells (DC) are viewed as the most efficient APC. Since the recognition of DCs as the professional APC, the paradigm has emerged that macrophage (MPhi) are scavengers and are incapable of activating T cells.


METHODS
The melanoma-associated MART-1(27-35) peptide-loaded MPhi from HLA-A2-positive donors were used to activate MART-1(27-35) epitope-specific CTL in vitro.


RESULTS
We show that peptide-pulsed MPhi stimulate MART-1(27-35) epitope-specific precursors to proliferate and to express effector functions. We also show that upon restimulation with the peptide pulsed MPhi, a fraction of the epitope-specific CTLs undergoes activation-induced cell death. The activation-induced cell death is induced in an epitope-specific manner and through apoptosis.


CONCLUSIONS
MPhi can function as APC and are also capable of modulating expansion and contraction of CTL response in vitro.
Mehrotra
Shikhar
S
Department of Medicine, University of Connecticut School of Medicine, Farmington, CT, USA. mehrotr@musc.edu
Zaidi
Nisar
N
Chakraborty
Nitya G
NG
Mukherji
Bijay
B
D017951:Antigen Presentation / Q000276:immunology*; D000938:Antigen-Presenting Cells / Q000276:immunology; D017209:Apoptosis / Q000276:immunology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology; D000939:Epitopes / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D005434:Flow Cytometry; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D009363:Neoplasm Proteins / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
D000939:Epitopes; D018984:Epitopes, T-Lymphocyte; C105787:MART-1-Melan-A(27-35) epitope; D009363:Neoplasm Proteins