Abstract: The invention relates to a method of accelerating the induction of somatic mutations in vitro. The inventive method comprises the expression of at least one cDNA expressing a modified version of the AID gene in the cells to be mutated, in culture conditions and a medium that are suited thereto, said modified version resulting from an AID gene in which the three hydrophobic amino acids, leu189, phe193 and leu196, have been replaced by means of alanine mutations in each case. The invention can be used to induce mutations in Burkitt's lymphoma BL2. The invention can also be used to induce mutations in the immunoglobulin genes of immortalised antibody-producing cells, such as mouse hybridoma cells, human hybridoma cells or human B-cell lines immortalised by the Epstein-Barr virus (EBV).

Abstract: The invention concerns a method for inducing somatic mutations in vitro or ex vivo, comprising (1): adding to the cells to be mutated, in culture conditions and in a medium suited to said cells, of at least a combination of anti-IgM and anti-CD19 and/or anti-DC21 antibodies, while (2) said anti-IgM antibodies are biotinylated and are subjected to specific aggregation by streptavidin coupled with a support. Advantageously, the mutations are controlled and/or adjusted by inhibiting and reactivating and/or stimulating DNA polymerase pol iota. The invention is in particular applicable to rapid and controlled induction of mutations on the BL2 Burkitt's lymphoma.

Abstract: The invention concerns a method for inducing somatic mutations in vitro or ex vivo, comprising (1): adding to the cells to be mutated, in culture conditions and in a medium suited to said cells, of at least a combination of anti-IgM and anti-CD19 and/or anti-DC21 antibodies, while (2) said anti-IgM antibodies are biotinylated and are subjected to specific aggregation by streptavidin coupled with a support. Advantageously, the mutations are controlled and/or adjusted by inhibiting and reactivating and/or stimulating DNA polymerase pol iota. The invention is in particular applicable to rapid and controlled induction of mutations on the BL2 Burkitt's lymphoma.

Abstract: The invention concerns an immunogenic composition, in a pharmaceutically acceptable carrier, for specifically stimulating a sub-population of B M+D+CD27+ cells so as to provide T-independent anti-bacterial response in said cells. The invention also concerns the use for producing T-independent anti-bacterial immune responses in subjects infected or susceptible of being infected by polysaccharide bacteria (streptococcus, meningococcus, pneumococcus, hemophilus influenza) or by protein capsid viruses (poliovirus, encephalomyocarditis virus, influenza virus).