gammadelta T cells are a component of early immunity against preerythrocytic malaria parasites.

Published

Journal Article

We tested the hypothesis that gammadelta T cells are a component of an early immune response directed against preerythrocytic malaria parasites that are required for the induction of an effector alphabeta T-cell immune response generated by irradiated-sporozoite (irr-spz) immunization. gammadelta T-cell-deficient (TCRdelta(-/-)) mice on a C57BL/6 background were challenged with Plasmodium yoelii (17XNL strain) sporozoites, and then liver parasite burden was measured at 42 h postchallenge. Liver parasite burden was measured by quantification of parasite-specific 18S rRNA in total liver RNA by quantitative-competitive reverse transcription-PCR and by an automated 5' exonuclease PCR. Sporozoite-challenged TCRdelta(-/-) mice showed a significant (P < 0.01) increase in liver parasite burden compared to similarly challenged immunocompetent mice. In support of this result, TCRdelta(-/-) mice were also found to be more susceptible than immunocompetent mice to a sporozoite challenge when blood-stage parasitemia was used as a readout. A greater percentage of TCRdelta(-/-) mice than of immunocompetent mice progressed to a blood-stage infection when challenged with five or fewer sporozoites (odds ratio = 2.35, P = 0.06). TCRdelta(-/-) mice receiving a single irr-spz immunization showed percent inhibition of liver parasites comparable to that of immunized immunocompetent mice following a sporozoite challenge. These data support the hypothesis that gammadelta T cells are a component of early immunity directed against malaria preerythrocytic parasites and suggest that gammadelta T cells are not required for the induction of an effector alphabeta T-cell immune response generated by irr-spz immunization.

Full Text

Duke Authors

Cited Authors

  • McKenna, KC; Tsuji, M; Sarzotti, M; Sacci, JB; Witney, AA; Azad, AF

Published Date

  • April 2000

Published In

Volume / Issue

  • 68 / 4

Start / End Page

  • 2224 - 2230

PubMed ID

  • 10722623

Pubmed Central ID

  • 10722623

International Standard Serial Number (ISSN)

  • 0019-9567

Digital Object Identifier (DOI)

  • 10.1128/iai.68.4.2224-2230.2000

Language

  • eng

Conference Location

  • United States