Principal Investigator
B Cell Response to Viruses that Infect the Respiratory Tract (M. Sangster)
An electron micrograph of a section of lung tissue infected with influenza virus 14 days previously. The image shows the presence of an antibody secreting B cell located in the airway. This may be one of the B cells that is making antibodies which protect from influenza infection. The wavy lines that surround the nucleus of the cell (demarcated by the letter B
) are layers of endoplasmic reticulum where the antibody proteins are synthesized by the B cell for secretion into the surrounding tissue.
Virus-specific antibodies play a key role in providing a protective barrier to infection and in facilitating viral clearance once an infection is established. Antibody-producing cells or plasma cells are generated from B cells that divide and differentiate following recognition of specific antigen. A critical requirement for optimal antibody responses is the cognate help delivered to activated B cells by CD4 T cells. This help is important for directing antibody isotype switching in B cells, the process by which B cells switch from expressing IgM to expressing alternative isotypes (such as IgG1, IgG2a, and IgA in the mouse) with different functional characteristics. In addition, cognate T cell help is critical if activated B cells are to participate in germinal center reactions, where affinity maturation of the antibody response takes place and the cellular elements of B cell memory are generated.
These elements include long-lived plasma cells, which maintain high levels of protective antibodies, and a population of memory B cells that will respond with rapid antibody production on re-exposure to cognate antigen. This brief overview grossly simplifies a remarkable and complex process that is regulated at many levels in ways that modulate the kinetics, magnitude, and quality of the acute B cell response, as well as characteristics of dispersed plasma cell and memory B cell populations. In general terms, our research is aimed at understanding the characteristics of optimally effective B cell responses and applying this knowledge towards the improvement of vaccination regimens.
« back to all projectsResearch Projects
