Research for innovation: a teaching sequence on the argumentative approach to probabilistic thinking in grades I-V and some related basic research results

In the frame of the "Research for innovation", this paper presents the preparation, planning, classroom implementation, revision and wider experimentation of a long term (Grade I - Grade V) innovative teaching sequence on the argumentative approach to probabilistic thinking, conceived in the perspective of the teaching and learning of mathematics in the "fields of experience." It also presents some developments of basic research, which deal with the hypotheses underlying the planning of the teaching sequence and its classroom implementation. In particular, the basic research presented concerns the mechanisms of argumentative construction of probability knowledge in the classroom: three mechanisms (related to the constructive functions of natural language) will be exhibited, and the conditions for their activation will be discussed

Selective identification of HLA-DP4 binding T cell epitopes encoded by the MAGE-A gene family

Because of the high frequency of HLA-DP4 in the Caucasian population, we have selectively delineated HLA-DP4 restricted T cell epitopes in the MAGE-A tumor antigens. We identified 12 good binders to HLA-DP4 and investigated the capacity of the seven best binders to induce in vitro specific CD4+ T cell lines from HLA-DP4 healthy donors. We found that the MAGE-A1 90-104 peptide exhibited a high and constant frequency of CD4+ T cell precursors in all the six tested donors. The MAGE-A1 268-282 peptide was found immunogenic in only two donors but with a high precursor frequency. The MAGE-A12 127-141 peptide was T cell stimulating in six different donors and induced fewer T cell lines. The peptide-specific T cell lines were stimulated by DC loaded with the lysates of cells transfected with MAGE-A1 or MAGE-A12, or loaded with the recombinant protein. We also show that the immunoreactivity of CD4+ T cell epitopes restricted to the same HLA II molecule may vary from one individual to another, as a result of inter-individual variations in the CD4+ T cell repertoire