Abstracts (complete list) - Wissenschaft Online

Filiz Demircik, Ari Waisman
The role of B cells and other antigen presenting cells in
infections
To clarify the role of B cells in infection models like Leishmania major, murine
Cytomegalovirus (MCMV) and influenza, we are using three different mouse strains. The
JHT mice are B cells deficient; the IgG1i strain has B cells producing and secreting IgG1
antibodies but no other antibody isotypes; and the IgMi mice, which can produce IgM as
the B cell receptor but have no antibodies in the sera. In these mouse strains we are
looking for differences in the T cell repertoire that is established upon infection.
Furthermore we want to deplete B cells and thereby look at their role in infection. To
deplete B cells at distinct time points during, before or after clearing of the infection, we
will establish a CD19-Cre x iDTR mouse. In this developed novel iDTR system, the
diphtheria toxin receptor (DTR) can be expressed on the surface of cells following a Cremediated
deletion of a STOP cassette. In the iDTR mice, lineage ablation is achieved by
injecting diphtheria toxin (DT) into mice expressing the iDTR as well as a tissue specific
Cre transgene. Finally we plan to create a new mouse with the DTR downstream of the
CD11b promoter and then together with lineage specific Cre mouse strains we will be
able to achieve a more specific ablation, especially for antigen presenting cells and be
able, for example, to specifically delete cells that express CD11b and CD11c or CD11b
and LysM. This system will allow us to specifically ablate sub-populations of dendritic
cells, macrophages or B cells (B-1 cells) and study their role in different infectious
systems.