|
|
||||||||
-Dependent CD4 Cell Immunity1


* Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106; and
Section of Endocrinology, University Hospitals, Ulm, Germany
The low frequency of tumor Ag-specific T cells in vivo has made it
challenging to directly measure their clonal sizes and cytokine
signatures. We used a new generation ELISPOT approach to study the
constitutive immunogenicity of the RMA tumor in syngeneic B6 mice and
adjuvant-guided immunity against an MHC class II-restricted RMA
peptide, H11.1. The RMA tumor was found to activate cells of the innate
immune system and to induce a type 1 polarized, RMA-specific CD4 and
CD8 T cell response. With clonal sizes
10/106, the
magnitude of this constitutively induced immune response did not
suffice to control the tumor cell growth. In contrast, immunization
with H11.1 peptide, using an immunostimulatory CpG oligonucleotide or
CFA as adjuvant, engaged
25- or
10-fold higher clonal sizes of
type 1 polarized CD4 cells, respectively. Therefore, the CpG
oligonucleotide functioned as a stronger type 1 adjuvant and, unlike
CFA, elicited protective immunity. The protection was IFN-
dependent, as it was not inducible in IFN-
knockout mice. Therefore,
CpG adjuvant-guided induction of type 1 immunity against tumor Ags
might be a promising subunit vaccination
approach.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |