The development of effector and memory T cells in cutaneous leishmaniasis: the implications for vaccine development.
Leishmania major infections induce the development of a CD4(+) T-helper 1 (Th1) response that not only controls the primary infection but also results in life-long immunity to reinfection. How that immunity is maintained is unknown, although because of the existence of infection-induced immunity, there has been an assumption that the development of a vaccine against leishmaniasis would be relatively easy. This has turned out not to be the case. One problem has been the finding that a large part of the immunity induced by a primary infection depends upon the presence of persistent parasites. Nevertheless, there are ample situations where immunologic memory persists without the continued presence of antigen, providing the prospect that a non-live vaccine for leishmaniasis can be developed. To do so will require an understanding of the events involved in the development of an effective protective T-cell response and, more importantly, an understanding of how to maintain that response. Here, we review work from our laboratory, describing how Th1 cells develop in L. major-infected mice, the nature of the memory T cells that provide protection to reinfection, and how that information may be utilized in the development of vaccines.
Scott
Phillip
P
Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA. pscott@vet.upenn.edu
Artis
David
D
Uzonna
Jude
J
Zaph
Colby
C
D000818:Animals; D015195:Drug Design; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology*; D018320:Leishmania major / Q000254:growth & development / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology* / Q000469:parasitology; D051379:Mice; D008815:Mice, Inbred Strains; D016052:Protozoan Vaccines; D018417:Th1 Cells / Q000276:immunology*
D016052:Protozoan Vaccines