The adjuvant monophosphoryl lipid A increases the function of antigen-presenting cells.
The induction of immune responses in vivo is typically performed with antigens administered in external adjuvants, like alum, complete Freund's adjuvant, LPS and, more recently, monophosphoryl lipid A (MPL). However, the role of the adjuvant is still poorly defined. The aim of this study was to test whether the MPL affects the function of antigen-presenting cells (APC) in vitro and in vivo. Antigen-pulsed APC [including macrophages, B cells and dendritic cells (DC)] were incubated or not with MPL, and their ability to sensitize naive T cells was tested in vitro and in vivo. The data show that MPL enhances the ability of macrophages and B cells to sensitize naive T cells, and confers to them the capacity to induce the development of T(h)1 and T(h)2. Administration of MPL i.v. in mice results in the redistribution of fully mature DC in the T cell area of the spleen. These observations suggest that MPL may induce an antigen-specific primary immune response by provoking the migration and maturation of DC that are the physiological adjuvant of the immune system.
De Becker
G
G
Département de Biologie Moléculaire, Université Libre de Bruxelles, Rue des Prof. Jeener et Brachet 12, 6041 Gosselies, Belgium.
Moulin
V
V
Pajak
B
B
Bruck
C
C
Francotte
M
M
Thiriart
C
C
Urbain
J
J
Moser
M
M
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D000938:Antigen-Presenting Cells / Q000187:drug effects*; D001402:B-Lymphocytes / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D003713:Dendritic Cells / Q000187:drug effects / Q000502:physiology; D005260:Female; D008050:Lipid A / Q000031:analogs & derivatives* / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C
D000276:Adjuvants, Immunologic; D008050:Lipid A; D008070:Lipopolysaccharides; C048436:monophosphoryl lipid A