CSP--a model for in vivo presentation of Plasmodium berghei sporozoite antigens by hepatocytes

PLoS One. 2012;7(12):e51875. doi: 10.1371/journal.pone.0051875. Epub 2012 Dec 18.

Abstract

One target of protective immunity against the Plasmodium liver stage in BALB/c mice is represented by the circumsporozoite protein (CSP), and mainly involves its recognition by IFN-γ producing specific CD8+T-cells. In a previous in vitro study we showed that primary hepatocytes from BALB/c mice process Plasmodium berghei (Pb) CSP (PbCSP) and present CSP-derived peptides to specific H-2k(d) restricted CD8+T-cells with subsequent killing of the presenting cells. We now extend these observations to an in vivo infection model in which infected hepatocytes and antigen specific T-cell clones are transferred into recipient mice inducing protection from sporozoite (SPZ) challenge. In addition, using a similar protocol, we suggest the capacity of hepatocytes in priming of naïve T-cells to provide protection, as further confirmed by induction of protection after depletion of cross-presenting dendritic cells (DCs) by cytochrome c (cyt c) treatment or using traversal deficient parasites. Our results clearly show that hepatocytes present Plasmodium CSP to specific-primed CD8+T-cells, and could also prime naïve T-cells, leading to protection from infection. These results could contribute to a better understanding of liver stage immune response and design of malaria vaccines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigen Presentation*
  • Antigens, Protozoan / immunology*
  • CD8-Positive T-Lymphocytes / immunology
  • Cytochromes c / administration & dosage
  • Cytokines / metabolism
  • Epitopes, T-Lymphocyte / immunology
  • Hepatocytes / immunology*
  • Hepatocytes / parasitology
  • Lymphocyte Activation / immunology
  • Malaria / immunology
  • Malaria / parasitology
  • Mice
  • Plasmodium berghei / immunology*
  • Protozoan Proteins / immunology*
  • Spleen / immunology
  • Spleen / parasitology
  • Sporozoites / immunology*

Substances

  • Antigens, Protozoan
  • Cytokines
  • Epitopes, T-Lymphocyte
  • Protozoan Proteins
  • circumsporozoite protein, Protozoan
  • Cytochromes c

Grants and funding

The authors have no support or funding to report.