A faculty team works to create content linkages among various courses to increase meaningful learning of targeted concepts of microbiology.

As research faculty with expertise in the area of host-pathogen interactions (HPI), we used a research group model to effect our professional development as scientific educators. We have established a working hypothesis: The implementation of a curriculum that forms bridges between our seven HPI courses allows our students to achieve deep and meaningful learning of HPI concepts. Working collaboratively, we identified common learning goals, and we chose two microorganisms to serve as anchors for student learning. We instituted variations of published active-learning methods to engage students in research-oriented learning. In parallel, we are developing an assessment tool. The value of this work is in the development of a teaching model that successfully allowed faculty who already work collaboratively in the research area of HPI to apply a "research group approach" to further scientific teaching initiatives at a research university. We achieved results that could not be accomplished by even the most dedicated instructor working in isolation.

Stability of the B cell antigen receptor modulates its signaling and antigen-targeting functions.

The binding of antigens to the B cell antigen receptor (BCR) results in the initiation of signaling cascades and the internalization of the antigens for processing and presentation. Recent studies indicate that antigen binding destabilizes the BCR as a mechanism to down-regulate B cell responses. Two point mutations in the transmembrane domain of murine membrane IgM (mIgM) (YS to VV) weaken the interaction of mIgM with Igalpha/Igbeta heterodimer, resulting in a destabilized BCR. Using muYS/VV BCR, effects of the destabilized BCR on the functions of an endogenous wild-type mIgG(2a) BCR were analyzed. The muYS/VV BCR is defective in signaling and does not target antigens to late endocytic compartments for processing and presentation. Coligation of the muYS/VV BCR with the endogenous BCR interferes with antigen-targeting functions of the endogenous BCR. Thus, the destabilized BCR has a dominant effect, down-regulating the function of stable wild-type BCR. The ability of the destabilized BCR to influence the stable BCR may play an important role in turning off B cell responses for antigen-driven anergy and tolerance.