Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Characterisation of CSFV peptide-specific T-helper cell responses

The cytokine response of T helper (Th) cells stimulated with antigen can be grouped in a Th1-like or Th2-like response. This has major consequences for the quality of specific effector immune response such as antibody production and cytotoxic activity of T cells.

In this Project we have identified the phenotype of the responding T -helper cell population, determined the frequency of the peptide-specific T -helper cells and the cytokine production pattern (IL-4/ IFN-y). For the characterisation of the CSFV -peptide specific T -cell response PBMC derived from CSFV strain Glentorf-infected dd-haplotype swine were restimulated with synthetic peptides formerly identified in 3H-thymidine proliferation assays as potential T-cell epitopes.

For the restimulation experiments for the more detailed analyses of the T-cell response 14 peptides derived from the non-structural protein region were used. In a first step the responding T -cell subpopulations were characterised in CFSE-proliferation assays by labelling of the in vitro peptide restimulated PBMC-cultures with antibodies against leukocyte differentiation antigens e.g. antibodies against CD4 and CD8. Different patterns of reactive cell subpopulation were obvious: besides peptides inducing nearly only a response of CD4 positive cells either with a weak or strong proliferation, peptides exists which showed a dear stimulatory activity for CD4+ and CD8?+ T lymphocytes. One peptide showed a clear preference for the stimulation of nearly only CD8+ cells. In further experiments for the discrimination of the peptideinduced T -cell response into Thl and Th2-type responses ELISPOT assays for the quantification of the frequency of cytokine producing cells were performed. No correlations could be identified between phenotype of peptide-stimulated cell populations and the frequency of IFN-y/or IL-4 producing cells. Nearly all-possible reactivity patterns were obvious. Peptides with high potency to stimulate IFN-gamma producing ceIls were found as weIl as peptides stimulating both IFN-gamma and IL-4 producing T -ceIls. Also the variation of the frequency of the responding ceIl populations was extremely heterogeneous.

Informazioni correlate

Contatto

Eberhard PFAFF, (DEPUTY HEAD OF INSTITUTE)
Tel.: +49-707-1967152
Fax: +49-707-1967303
E-mail