These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: B7-2 blockade enhances T cell responses to Leishmania donovani. Author: Murphy ML, Engwerda CR, Gorak PM, Kaye PM. Journal: J Immunol; 1997 Nov 01; 159(9):4460-6. PubMed ID: 9379045. Abstract: Infection with Leishmania donovani has been reported to induce a dominant Th1-type response in all strains of mice examined, providing a model for examining the regulation of Th1 responses in the relative absence of Th2 cross-regulation. Here we demonstrate that blockade of the costimulatory molecule B7-2, but not B7-1, has significant effects on disease progression, measured as day 28 parasite burden in the liver. The effects of B7-2 blockade were associated with increased IFN-gamma production, as determined 1) following restimulation with specific Ag, 2) by enumeration of IFN-gamma-secreting cells using ELISPOT assays, and 3) by analysis of IFN-gamma mRNA by reverse transcription-PCR. Surprisingly, IL-4-producing cells were also readily detected in infected mice by ELISPOT analysis. The frequency of these IL-4-producing cells and of IL-4 mRNA levels was also enhanced in the liver of infected mice treated with anti-B7-2 mAb. Administration of anti-B7-2 from the day of infection or delaying its administration until day 3 after infection had similar effects. Parasite-specific IgG1 and IgG2a responses were either unaffected or marginally increased following anti-B7-2 administration, contrary to the inhibitory effect of this treatment on responses to the T-dependent Ag DNP-BSA. These data support a model of T cell activation whereby B7-2/CD28 interactions play a relatively redundant role in initial T cell activation, but in which interference with later B7-2/CTLA4 interaction potentiates established cytokine responses.[Abstract] [Full Text] [Related] [New Search]